January 23, 2026

No End in Sight for Simcoe County and Grey-Bruce as Endless Snow Squalls Bring the Risk of Over 50cm More Snow on Friday

January 23, 2026/ Brennen Perry

***NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE***

Here we go again, say it ain’t snow. It should come as no surprise to residents across the snowbelt east of Lake Huron and southeast of Georgian Bay that more snow is on the way to end the week. After a relentless stretch of lake effect activity, snow squalls are set to ramp back up on Friday as activity currently over Muskoka and the Bruce Peninsula drops southward into Simcoe County and Grey-Bruce.

These areas are no strangers to snow squalls at this point, as they have been dealing with them on and off for much of the past week. Simcoe County did manage to sneak in a brief break on Thursday, but that lull will be short lived. Friday is shaping up to be a sharp reminder of just how powerful these lake effect streamers can be, with snowfall totals quickly piling up once again. By Saturday morning, many communities could be digging out from an additional 25-50cm of snow.

In some localized areas, especially portions of southern Bruce County south of Owen Sound, snowfall totals could push even higher. Some model guidance continues to hint at locally over 50cm where bands become most persistent. On top of that, blowing snow will once again be a major concern. Wind gusts approaching 60 km/h will combine with an already deep snowpack to create widespread drifting. As a result, many local roads and highways are likely to remain closed, and that list could grow through the day Friday as conditions deteriorate.

As snow squalls begin to weaken overnight Friday into early Saturday, the focus will quickly shift to the cold. This setup is expected to deliver what could be the coldest night in years across much of Southern Ontario. Wind chills could plunge into the -40s in some areas, with nearly all of Southern Ontario seeing wind chills in the -30 range by Saturday morning.

Overnight, snow squall activity currently affecting Parry Sound and Muskoka is expected to migrate southward and settle somewhere between southern Muskoka and northern Parry Sound by mid-morning Friday. This band could become quite persistent as it drifts south, heavily impacting travel corridors.

Highway 400 between MacTier and Barrie and Highway 11 between Bracebridge and Orillia look especially vulnerable. Rapidly accumulating snowfall and poor visibility could lead to partial or full closures along these stretches as conditions worsen throughout the day.

By the afternoon, strong wind gusts in the 60 to 70 km/h range are expected to develop. This will significantly increase the risk of blowing snow and near zero visibility, making travel extremely hazardous even in areas not seeing the heaviest snowfall rates.

**Hourly snowfall rates (cm)** - MAP FROM WEATHERBELL

Attention will also turn to Lake Huron, where more organized lake effect activity is expected to develop east of the lake Friday afternoon. Current model guidance suggests the most intense and focused band will set up somewhere between Owen Sound and Kincardine, extending inland toward Hanover.

This band has the potential to lock in for an extended period through much of Friday afternoon and evening. Where it becomes stationary, snowfall totals could become extreme. Under the right conditions, some localized spots could see 50cm or more, with an outside chance of totals approaching 75 to 100cm if everything lines up just right. Hourly snowfall rates could approach 10cm at times, with very cold air helping boost snowfall ratios and intensify accumulations.

Additional lake effect activity is also expected to impact Huron and Perth counties, although this snow looks less intense and more spread out. Even so, gusty winds throughout the afternoon will create treacherous travel conditions, especially in open areas that are particularly prone to blowing and drifting snow.

Expect ongoing and possibly expanding highway closures across Grey-Bruce, Huron, and Perth counties throughout the day on Friday as conditions remain dangerous.

As we head into Friday night, the Georgian Bay snow squall affecting Simcoe County should gradually weaken and retreat back toward the shoreline around midnight. Snowfall rates will ease, but blowing snow may remain an issue for a time.

The Lake Huron snow squall impacting Grey-Bruce is expected to linger overnight, though it should slowly weaken heading into Saturday morning. As winds ease and the fetch shortens, bands will gradually retreat closer to the lake.

As always with lake effect snow, totals can vary dramatically over short distances due to the narrow and highly localized nature of these bands. That said, there is fairly strong model agreement that the hardest hit area will fall somewhere around Port Elgin, Chatsworth, and Hanover. An intense and persistent squall in this corridor could lead to over 50cm of snow by Saturday morning.

Communities such as Owen Sound, Flesherton, Mildmay, and Kincardine, along with Midland, Orillia, Wasaga Beach, and Gravenhurst, can expect widespread snowfall totals in the 25-50cm range. There is still some uncertainty with the exact placement of the Georgian Bay squall, with some models keeping it tighter and others spreading it out more. Because of that uncertainty, the zone for 25cm or more stretches from Gravenhurst south toward just north of Barrie, even though the actual hardest hit area will likely be smaller.

The City of Barrie sits right on the southern edge of the main snow squall zone. At this point, it appears Barrie will narrowly miss the worst of the snow, keeping totals closer to 15-25cm, especially toward the south end of the city. That said, there is still a chance the squall dips farther south than expected. One model does bring heavier snow into Barrie, which means locally higher totals closer to 35cm cannot be ruled out.

Elsewhere across Grey-Bruce and into northern sections of Huron, Perth, Wellington, and Dufferin counties, snowfall totals in the 15-25cm range look likely. Some localized areas could still end up closer to 30 or even 35cm, depending on how individual bands evolve.

Lower snowfall amounts are expected across the Greater Toronto Area. However, the Lake Huron squall could brush parts of the western Golden Horseshoe, bringing a quick few centimetres in spots. Farther east, including Durham Region and the Kawartha Lakes, the Georgian Bay squall could deliver around 5-10cm.

Little to no snow is expected across deep southwestern Ontario and far eastern Ontario, which is why those areas are not highlighted on the snowfall map.

While snow squalls begin to wind down overnight Friday, the cold will only continue to intensify. Saturday is shaping up to be potentially the coldest day many areas have experienced in years. Some locations, including Toronto, could be looking at their coldest Saturday morning since 2016.

Temperatures are expected to drop near -30˚C across central and eastern Ontario, with wind chills making it feel between -35˚C and -40˚C. Areas east of Lake Huron and around parts of the Golden Horseshoe may be slightly less cold, but still dangerously so.

Across the western GTA, Hamilton, and Niagara, temperatures should hover in the low -20s, though wind chills will still make it feel close to -30˚C. A similar pattern is expected for parts of Bruce and Huron counties closer to Lake Huron, where slightly milder air off the lake may keep temperatures a few degrees warmer.

Northern Ontario will be under the core of this polar air mass, with some of the coldest air on Earth spilling south. Temperatures there could dip near or below -35˚C, with wind chills approaching -45˚C across much of the region. Some model guidance even suggests wind chills near -50, though that remains uncertain.

Once the cold settles in, attention will quickly turn to the next potential system. A high-impact snowstorm is showing signs of developing and could bring significant snowfall across a wide swath of Southern Ontario heading into Monday. Current model trends suggest over 30cm of snow is possible in some areas, including parts of the Greater Toronto Area.

A preliminary forecast for that system will be issued on Friday as we continue to monitor trends and fine-tune the details. Stay tuned.

January 21, 2026

Snowy One-Two Punch Targets Southern Ontario Starting Wednesday as Alberta Clipper and Squalls Dump Up to 25 to 50 cm of Snow

January 21, 2026/ Brennen Perry

The story of the week so far across Southern Ontario has been the relentless snow squall activity that has been hammering the region, bringing treacherous travel conditions as a surge of Arctic air continues to sit overhead. These squalls have been anything but minor, producing frequent whiteouts, rapidly deteriorating road conditions, and dangerous travel at times.

The worst of the impacts on Tuesday was when intense snow squalls forced the closure of multiple stretches of Hwy 11 between Bracebridge and Orillia. Whiteout conditions combined with rapidly accumulating snow led to several accidents, leaving many drivers stranded and highlighting just how dangerous these squalls can become when they lock into place.

While the snow squalls are far from finished, the threat zone is expected to shift over the next few days as winds gradually turn more westerly. This change in wind direction will push the most persistent squall activity away from areas that were hit earlier this week and refocus it further west and north.

As a result, locations such as the Bruce Peninsula, Muskoka, Parry Sound, and even areas further inland like Haliburton and Bancroft are expected to see the most significant impacts through the second half of the week.

Snow squall activity will briefly weaken during the day on Wednesday, but this will not be because the atmosphere is calming down. Instead, an Alberta Clipper is expected to move into Southern Ontario beginning Wednesday morning, temporarily disrupting the lake effect setup.

This clipper will spread a shield of steady light to moderate snow across Southwestern Ontario, extending through the Golden Horseshoe and into Eastern Ontario as the day goes on. While this system is not expected to produce extreme snowfall amounts on its own, it will still have notable impacts due to its timing and the already poor road conditions in many areas.

Compared to the storm some locations experienced last week, snowfall totals with this system will be more modest. However, the combination of falling snow, reduced visibility, and slick road surfaces could still make both the morning and evening commute hazardous in spots.

At this point, we are expecting a general 5 to 10 cm from the Alberta Clipper. As is typical with these systems, snowfall will not be uniform. Alberta Clippers are often moisture-starved, which can lead to dry pockets where snowfall totals underperform, while narrow bands of heavier snow can locally boost amounts closer to 15 cm.

Snow squalls that are already developed east of Georgian Bay will continue to impact the Parry Sound and Muskoka region through the overnight hours and into Wednesday morning. Travel conditions in these areas will remain poor early in the day, especially where bands remain persistent.

As the clipper approaches, winds will begin to shift by mid-morning, weakening the squalls and temporarily shutting down the lake effect snow machine. This will offer a short-lived improvement in conditions for areas east of Georgian Bay before the next phase of the pattern kicks in.

The outer bands of snow associated with the Alberta Clipper will begin to move into Deep Southwestern Ontario around sunrise, affecting areas such as Windsor, Sarnia, and Chatham. From there, the snow will steadily expand northeastward through the late morning hours.

By midday, snow will be falling across much of Southwestern Ontario and into the Golden Horseshoe and Central Ontario. Snowfall rates are not expected to be overly intense, generally topping out around 1-2 cm per hour, but wind gusts of 40 to 60 km/h could still lead to areas of blowing snow and reduced visibility.

Model guidance is also hinting at the development of a dry slot north of the GTA, particularly around Lake Simcoe. This includes areas such as Collingwood, Barrie, and parts of York Region, where snowfall rates could be noticeably lower.

This is a common issue with Alberta Clippers. While the Great Lakes can often help enhance snowfall by adding moisture, regions around Lake Simcoe may miss out when winds are predominantly southerly. In this setup, they sit outside the direct influence of Lake Erie and Lake Ontario moisture feeds.

On the flip side, the Toronto to Kingston corridor is expected to benefit from Lake Ontario enhancement. This added moisture could push snowfall totals closer to 10 to 15 cm in this zone, slightly higher than surrounding areas.

This enhanced snowfall is also expected to coincide with the evening commute, particularly along Hwy 401 east of Toronto toward Kingston. Drivers should be prepared for rapidly changing conditions, with visibility dropping quickly at times as heavier bursts of snow move through.

Light snow will also spread into the Ottawa Valley by early afternoon. However, snowfall totals will likely taper off the further north you go as the influence of Lake Ontario weakens. Ottawa itself may only pick up a few centimetres by the time the snow winds down Wednesday evening.

Snow from the clipper is expected to gradually taper off from west to east by the late afternoon or early evening as the system exits Eastern Ontario. Unfortunately, this break will be brief for snowbelt regions.

As the system departs, lake effect snow is expected to rapidly redevelop overnight Wednesday as winds settle into a southwesterly direction. This will allow the lake effect machine to roar back to life.

The brunt of the snow squall activity overnight will be focused on the Bruce Peninsula, Parry Sound, and North Muskoka. At times, these squalls could stretch further inland toward areas like Sundridge and even North Bay.

Travel conditions overnight into Thursday are expected to be very poor. Snowfall rates may become intense within the strongest bands, and it is quite possible that sections of Hwy 400 or Hwy 11 could see temporary closures if snow accumulates faster than crews can keep up. Travel in these areas is highly discouraged.

By sunrise Thursday, winds are expected to gradually turn more westerly. This shift will cause the main squall to sink southward into Muskoka, targeting locations such as Bracebridge, Port Carling, Baysville, Port Sydney, Rosseau, and MacTier.

Some model guidance suggests this squall could become nearly stationary through much of the day Thursday. If this scenario verifies, snowfall totals could quickly climb, with some areas potentially exceeding 50 cm by the end of Thursday.

Other models suggest a more oscillating band that shifts north and south throughout the day. While this would limit extreme totals in one single location, it would spread significant snowfall across a broader portion of Muskoka and Parry Sound.

As we head into Thursday afternoon, the impacts of the Georgian Bay squall may extend beyond the typical snowbelt. Strengthening winds could allow the band to push further inland, potentially reaching parts of Eastern Ontario and even the Ottawa Valley.

Locations such as Bancroft, Smiths Falls, Renfrew, and Ottawa could see several hours of heavy snow, leading to sudden whiteout conditions right during the evening commute. These whiteouts can occur with very little warning, making it critical for drivers to remain alert and be ready to adjust their driving immediately.

It could also bring a quick 5-10cm to the Ottawa Valley, which, combined with the Alberta Clipper, puts them in the 5-15cm range despite missing the worst of the clipper.

Additional lake effect snow is also possible east of Lake Huron during the day on Thursday, affecting Grey Bruce, along with parts of Huron and Perth Counties. While models are not showing a well-organized band at this time, wind gusts near 60 km/h could still lead to blowing snow and reduced visibility.

Snow squall activity is likely to persist into Thursday night and possibly into Friday morning. This forecast cuts off at the end of Thursday, with a separate update planned to cover Friday and beyond.

In terms of snowfall totals, most areas away from the lake effect are expected to see around 5 to 10 cm from the Alberta Clipper alone. Some pockets will fall short of that, while others may exceed it slightly, depending on lake enhancement.

That is why regions not expecting lake effect snow are generally placed in the 5 to 15 cm range. This includes much of Eastern Ontario, parts of the eastern GTA, and most of Southwestern Ontario.

Exceptions include areas northwest of the GTA, such as Barrie, Keswick, Bradford, Orangeville, and Angus, as well as Deep Southwestern Ontario, including Windsor, Leamington, and Chatham. These locations are expected to see less moisture and may remain below 5 cm. The same applies to the western GTA and Hamilton.

Once lake effect snow is factored in, totals increase quickly east of Georgian Bay. This includes snowfall from early Wednesday before the clipper arrives and the more intense squalls that follow on Thursday.

Snowfall totals of 25 to 50 cm are expected for the Bruce Peninsula, including Wiarton, Lions Head, and Tobermory, as well as areas east of Georgian Bay such as Bracebridge, Huntsville, and Parry Sound. Muskoka in particular has the potential to exceed 50 cm if the squall becomes stationary on Thursday.

Further south and east, areas such as Midland, Gravenhurst, Minden, Haliburton, and Bancroft can expect around 5 to 10 cm from the system, with an additional 10 to 15 cm from lake effect snow. This puts totals in the 15 to 25 cm range, with locally higher amounts possible.

Southern Grey-Bruce, extending into portions of Huron and Perth Counties, including Owen Sound, Meaford, Hanover, and Listowel, is also expected to end up in the 15 to 25 cm range by the time all is said and done.

January 19, 2026

Southern Ontario Plunges Into the Deep Freeze With Dangerous Blizzard Conditions on Monday

January 19, 2026/ Brennen Perry

That January thaw is now firmly in the rearview mirror across Southern Ontario after a major winter storm last week reminded us that we are still very much in the heart of winter. That storm brought widespread snowfall to the region, with many areas picking up significant accumulations and some seeing totals in the 30 to 50 cm range by the time it wrapped up on Thursday.

While we are not expecting another large, widespread system-related snowstorm of that magnitude in the immediate future, the pattern is far from quiet. In fact, the bigger story going forward will be a prolonged stretch of much colder weather as we head deeper into January. A true deep freeze is set to take hold beginning early this upcoming week and is expected to persist for much of the remainder of the month.

With temperatures plunging and the Great Lakes still largely ice-free, the setup becomes ideal for an active period of lake effect snow. Cold polar air moving over relatively warm lake waters is the perfect fuel source for snow squalls, and that lake effect snow machine is about to kick into high gear.

Ironically, this could end up being one of the last notable lake effect events of the season, as colder temperatures later this month will eventually lead to increasing ice coverage. Once the lakes begin to freeze over, the moisture supply is cut off, and snow squalls shut down. For now, though, the lakes are open and very capable of producing heavy snow.

That lake effect machine is expected to come roaring to life starting on Monday. By the time activity winds down late Tuesday, some communities could be digging out from substantial snowfall. Totals of 25 to 50 cm are possible in parts of Grey Bruce, Simcoe County and areas north of Parry Sound, although, as always with lake effect snow, not everyone will see those kinds of amounts.

Snow squall activity is expected to begin organizing overnight into Monday morning along the eastern Lake Huron shoreline. This activity will expand throughout the morning, affecting Grey Bruce, the Bruce Peninsula, and regions northeast of Georgian Bay. Additional lake effect bands are also expected to develop off Lakes Erie and Ontario, impacting parts of the Niagara region and Prince Edward County as early as Monday morning.

Conditions will deteriorate quickly on Monday afternoon as strong winds develop across much of Southern Ontario. Wind gusts of 60 to 90 km per hour are expected, and when combined with ongoing snow squalls, this could lead to dangerous blizzard conditions, particularly east of Lake Huron and in Prince Edward County.

The worst conditions are expected during the afternoon and early evening hours, with blowing snow and near zero visibility at times. There is also some concern that blowing snow could briefly impact parts of the Golden Horseshoe around the evening commute.

Through Monday night and into Tuesday morning, attention shifts toward a potentially intense and long-lasting snow squall. This band may set up across the Bruce Peninsula, extend across Georgian Bay, and come ashore into Simcoe County and possibly the Kawartha Lakes.

Some models suggest this squall could lock into place for 6 to 12 hours before finally lifting northward by Tuesday afternoon. Where it becomes stationary, snowfall rates could be intense, and accumulations could climb rapidly in a short period of time.

Adding to the concern will be the arrival of bitterly cold air late Monday. Temperatures will fall sharply, and by Tuesday morning, wind chills could make it feel like minus 20 degrees or colder across much of Southern Ontario. In some areas, wind chills could dip even lower.

When combined with heavy snow and strong winds, conditions could quickly become life-threatening for anyone who becomes stranded. Travel is strongly discouraged in the hardest hit regions beginning late Monday morning and continuing through Tuesday.

Lake effect snow will continue to organize overnight into Monday morning along Lake Huron, particularly around Grey Bruce. Bands will extend across the Bruce Peninsula and into areas northeast of Georgian Bay, including Parry Sound and even as far inland as North Bay at times.

While there is still some disagreement in the models regarding exact intensity, confidence is high enough to expect very poor driving conditions due to blowing snow and rapidly changing visibility, especially northeast of Georgian Bay, where the strongest bands are most likely.

There is also a more uncertain, but still concerning, snow squall signal for the Niagara region and the northeastern shoreline of Lake Ontario. The Canadian model shows a well-organized band coming off Lake Erie, moving across the Niagara region, then redeveloping over Lake Ontario and making landfall again across Prince Edward County and into the Kingston area. Other models are less aggressive with this scenario, particularly with the Lake Erie component, but there is better agreement that the Lake Ontario squalls will develop.

If this scenario plays out, it could lead to poor conditions and brief whiteouts during the Monday morning commute in parts of Niagara, as well as along portions of the Highway 401 corridor between Oshawa and Kingston.

By Monday afternoon, lake effect activity is expected to persist across Grey Bruce and areas northeast of Georgian Bay, although shifting winds may cause bands to weaken and reorganize at times. In the Niagara region, any squall activity should gradually sink south and east into upstate New York, with Niagara Falls and Fort Erie likely among the last locations to see conditions improve.

As winds shift, there is also a risk that a narrow but intense squall could sweep through Eastern Ontario during the afternoon, affecting areas such as Kingston, Brockville and Cornwall with sudden bursts of heavy snow and near zero visibility.

For many areas on Monday, the main impact may not be total snowfall amounts, but rather the combination of strong winds and blowing snow. Wind gusts of 60 to 90 km per hour across Southwestern Ontario and the Golden Horseshoe will make travel extremely difficult in open areas. East of Lake Huron, widespread road closures are very likely through the afternoon and early evening hours as conditions become too dangerous for travel.

Prince Edward County is also at risk of blizzard conditions if snow squalls persist there through the afternoon. Even modest snowfall rates can create severe conditions when combined with strong winds and exposed roadways.

Winds are expected to ease slightly on Monday evening, but blowing snow may continue overnight wherever squalls remain active.

As wind direction becomes better aligned during the evening, lake effect snow off Lake Huron may push further inland. This could allow poor visibility and blowing snow to extend into areas such as Kitchener, Barrie, Muskoka and the northern GTA around the dinner hour.

Confidence continues to increase for a more prolific snow squall to set up overnight Monday into Tuesday. This band may stretch across the Bruce Peninsula and move ashore from Georgian Bay into areas such as Midland, Barrie and Orillia. At times, it could reach far inland, potentially impacting the Kawartha Lakes and even the Peterborough area.

There is still some uncertainty regarding the exact placement. Some models focus the heaviest snowfall over northern Simcoe County, including Midland and Orillia, while others bring the core of the squall closer to Barrie. Regardless of exact placement, this squall could persist through Tuesday morning, remaining nearly stationary for several hours. Snowfall rates in the heaviest pockets could approach 10 cm per hour, which would lead to significant accumulations in a short amount of time.

What makes this setup particularly dangerous is what it will be accompanied by at the same time. This intense snow squall is expected to coincide with bitterly cold temperatures. Wind chills will drop into the minus 20s and even minus 30s in some areas starting Monday evening and continuing overnight into Tuesday morning. In these conditions, frostbite and hypothermia can develop very quickly, sometimes in just minutes.

If someone becomes stranded during one of these squalls, the situation can become life-threatening rapidly. Emergency services may struggle to reach those in need due to road closures and near-zero visibility, and snowplows simply cannot keep up with snowfall rates of 5 to 10 cm per hour. This is why staying off the roads in affected regions is strongly advised.

By Tuesday afternoon, the most persistent squall should lift north of Simcoe County and move into Muskoka and Parry Sound. The band may briefly reorganize Tuesday night ahead of another potential system arriving on Wednesday.

That system on Wednesday could bring a more widespread snowfall of around 5 to 15 cm across much of Southern Ontario. More details on that will be shared in a separate forecast closer to midweek.

When it comes to snowfall totals from this lake effect event, it is important to remember how localized these squalls can be. Accumulations can vary dramatically over short distances depending on where bands set up, how long they persist, and whether they wobble or remain stationary.

Our forecast highlights areas most at risk for higher totals, but not everyone within those zones will see the same amounts, and some locations could overperform if a band shifts unexpectedly.

The highest snowfall totals are most likely across Grey Bruce, particularly the Bruce Peninsula, where 25 to 50 cm of snow is possible. Areas on the peninsula are more likely to reach the upper end of that range, while locations farther south, such as Hanover and Flesherton, may be closer to 25 cm or could even fall short if bands stay to the north.

A similar 25 to 50 cm potential exists southeast of Georgian Bay, including Midland, Wasaga Beach, Barrie, Orillia, Washago and Beaverton. Areas northeast of Georgian Bay, north of Parry Sound, including Pointe au Baril and Britt, are also within this higher snowfall zone.

Amounts of 15 to 25 cm are expected for places such as Goderich, Point Clark, Wingham, Listowel, Minto, Shelburne, Lindsay, Fenelon Falls, Coboconk, Gravenhurst and Parry Sound.

Along the Lake Ontario shoreline, areas northeast of the lake, including Brighton, Belleville, Picton, Napanee and Kingston could also see 15 to 25 cm, with locally higher totals possible in spots like Picton if a band locks in.

The Niagara region, including Fort Erie, Niagara Falls, Niagara on the Lake, St. Catharines and Welland, is looking at generally 5 to 15 cm. Most locations will likely be closer to the lower end of that range, with Niagara Falls and Fort Erie having the best chance of seeing higher totals if a squall sets up nearby.

Elsewhere, including Woodstock, Kitchener, Fergus, Guelph, Orangeville, Keswick, Port Perry, Peterborough, Bracebridge, Huntsville, Haliburton, Cobourg and Brockville, totals of 5 to 15 cm are possible. Many of these areas will end up closer to 5 cm, but isolated locations could see higher amounts depending on how lake effect bands evolve.

For the GTA, London, deep Southwestern Ontario and the Ottawa Valley, snowfall amounts are expected to remain under 5 cm, although gusty winds and blowing snow may still impact travel at times.

December 31, 2025

Parts of Southern Ontario To Ring In the New Year Buried in Up to 100cm of Additional Snow by Thursday

December 31, 2025/ Brennen Perry

The weather story this week has been dominated by intense snow squalls that have practically paralyzed areas east of Lake Huron and southeast of Georgian Bay, and this prolonged event is far from finished.

As of Tuesday evening, many roads across Huron, Perth, Grey, Bruce and Simcoe Counties have been closed due to dangerous whiteout conditions and rapidly accumulating snow. Springwater Township has even issued an emergency alert asking residents to stay off the roads entirely, citing the inability for emergency services to safely respond.

Unfortunately, the situation is expected to continue into the New Year as snow squall activity remains locked in across the region. Additional road closures are possible as squalls continue to drift and redevelop through Grey and Bruce Counties on Wednesday. Blowing snow will remain a major concern, even during brief lulls in snowfall, keeping travel extremely hazardous.

With snow squalls persisting and slowly shifting over the next 48 hours, widespread snowfall totals east of Lake Huron are expected to range from 30 to 60cm by the end of Thursday. We continue to highlight a few high-impact pockets between Owen Sound and Goderich, including areas near Chatsworth, Wingham and Point Clark, where total snowfall could approach or even reach 100cm if the most intense bands remain locked in place.

Simcoe County will also continue to be affected on and off through Wednesday and Thursday. A narrow but intense zone that includes hard-hit Springwater Township, along with Wasaga Beach, Barrie and Angus, could pick up an additional 30 to 60cm of snow. Confidence is slightly lower here compared to Lake Huron, and some locations may underperform if the bands wobble, but significant impacts remain likely.

Late Wednesday into early Thursday morning, attention will also turn to Lake Ontario. A snow squall currently targeting upstate New York may drift northward into portions of Prince Edward County, including Picton. If this materializes, snowfall rates could quickly ramp up, leading to a fast 15 to 30cm of accumulation in just a few hours.

Snow squall activity is expected to continue into Friday, though the pattern begins to evolve. A more westerly flow later Thursday and Friday would favour the Bruce Peninsula, northern Simcoe County and Muskoka for continued lake effect snowfall.

Overnight, snow squall activity is expected to consolidate into two primary bands between Owen Sound and Goderich. Meanwhile, activity off Georgian Bay may briefly weaken overnight, although confidence in that outcome remains low. Radar trends continue to show a very robust squall set up between Orillia and Barrie, and even if it temporarily diminishes, it is expected to redevelop by mid-morning Wednesday.

The southern Lake Huron squall may also stretch farther inland at times, potentially reaching areas like Kitchener and parts of the western GTA, bringing brief but intense bursts of snow and rapidly changing road conditions.

These squalls are expected to persist through Wednesday morning and afternoon. By Wednesday evening, a weak Alberta clipper will move through Southern Ontario, briefly shifting winds and causing lake effect snow to become more scattered for a time.

That same clipper will also cause a wind shift over Lake Ontario, which could push an organized snow squall northward into Belleville, Picton and possibly Kingston. Snowfall rates in this band could reach 4 to 8cm per hour, with total accumulations of 15 to 30cm possible before the squall exits around midnight.

Snow squall activity should reorganize overnight into Thursday morning for regions east of Lake Huron and southeast of Georgian Bay as colder air deepens once again.

Based on the latest guidance, the strongest Lake Huron squall on Thursday looks most likely to set up somewhere near Kincardine, Wingham and Listowel, though this position could still shift. At the same time, the Georgian Bay squall is expected to continue hammering the Springwater and Barrie area.

By Thursday afternoon, the focus may shift northward as a multi-lake squall develops, stretching across the Bruce Peninsula, over Georgian Bay and into Midland and Orillia. Additional weaker bands may linger farther south across Huron and Perth Counties, including areas like Goderich and Stratford.

Looking ahead to Thursday night into Friday morning, the Georgian Bay squall may intensify further as winds become more westerly. This would allow the band to push northward into southern Muskoka, where it could lock in for much of the day Friday. A separate forecast focusing on Friday and the weekend will be issued closer to that time.

Before getting into final snowfall totals, it is important to remember that lake effect snow squalls are extremely localized. These narrow bands can produce massive snowfall in one community while areas just a few kilometres away receive very little. Forecast zones are intentionally broad to account for shifting winds and band placement, meaning not everyone within a zone will reach the listed totals.

With that in mind, there is strong model agreement on two primary zones with the highest snowfall potential ranging from 60 to 100cm, with localized amounts possibly exceeding 100cm if the most aggressive solutions verify.

The northern high-impact zone includes Owen Sound and Chatsworth, while the southern high-impact zone includes Point Clark and Wingham.

For the remainder of the eastern Lake Huron shoreline, snowfall totals of 30 to 60cm are expected, though isolated pockets could approach 75cm. Similar totals are possible from Wasaga Beach through Barrie, though totals there are more likely to remain on the lower end of the range.

Farther inland, areas including London, Woodstock, Kitchener, Fergus, Orillia, Innisfil, Keswick and Bradford could see 15 to 30cm. This is more conditional and depends on squalls stretching far enough inland in the right position.

That same 15 to 30cm potential also applies to parts of Prince Edward County, including Picton, where much of that snow could fall in a very short window Wednesday evening.

Surrounding regions extending southeast of London toward the Lake Erie shoreline, into Guelph, the north and eastern GTA, and along the Lake Ontario shoreline into Eastern Ontario could see 5 to 15cm by the end of Thursday. Most areas will likely stay closer to the lower end, though isolated pockets could approach 15cm due to intermittent lake effect bands.

The remainder of Southern Ontario, outside of northern Central and Eastern Ontario, can expect a general 2 to 5cm, mainly associated with the weak clipper system on Wednesday. Farther north, including the Ottawa Valley, less than 2cm is expected.

December 28, 2025

Powerful Wind Storm on Monday to Fuel Blizzard Conditions in Southern Ontario With Up to 25-50 cm of Snow Possible by Tuesday

December 28, 2025/ Brennen Perry

The major winter storm we have been focused on over the past few days has now arrived, bringing hazardous ice storm conditions to parts of Southern Ontario while Northern Ontario continues to deal with heavy snowfall. This system is already creating widespread travel issues and power concerns, and the worst impacts are still unfolding as we head into Monday.

Freezing rain will gradually come to an end by late morning or early afternoon on Monday for most areas as temperatures briefly climb above the freezing mark. While that may offer a short-lived improvement in conditions, it will be followed quickly by another round of dangerous weather as colder Arctic air surges back into the region from the west.

As this colder air pushes in, precipitation will rapidly transition from rain or freezing rain over to snow. This snow will become increasingly enhanced by Lake Huron and Georgian Bay, setting the stage for a prolonged and high-impact snow squall event across much of Southwestern and Central Ontario.

At the same time, a rapidly strengthening low-pressure system will track directly along the lower Great Lakes through early Monday. This setup will drive very strong winds across Southern and Northeastern Ontario, especially near the lakes, with widespread gusts exceeding 90 km/h and locally approaching or exceeding 100 km/h along exposed shorelines.

These powerful winds, when combined with heavy snowfall, will lead to blizzard conditions developing east of Lake Huron and southeast of Georgian Bay. Snow squalls will also intensify as the system pulls away, resulting in widespread snowfall totals of 25 to 50 cm across Grey-Bruce, Huron, Perth and Simcoe counties by the end of Tuesday.

The threat of blowing snow and sharply reduced visibility will not be limited to the traditional snowbelt regions. Localized blizzard conditions may extend across much of Southwestern and Central Ontario, including portions of the GTA. Even areas that do not receive significant snowfall could see near-zero visibility at times due to wind gusts in the 70 to 90 km/h range.

Given these conditions, road and highway closures are very likely in the hardest hit areas, especially across the snowbelt. Travel will be extremely hazardous and potentially impossible at times. Non-essential travel should be avoided through Monday and into Tuesday where possible.

Although winds are expected to gradually ease by early Tuesday, snow will continue to pile up east of Lake Huron and southeast of Georgian Bay. With very cold temperatures lingering through the remainder of the week, the snow squall risk could persist in some form for several additional days, depending on wind direction.

In the Ottawa Valley, freezing rain should come to an end by late morning on Monday as temperatures briefly rise above freezing. Meanwhile, colder air will already be invading areas closer to Lake Huron, with rain changing over to snow as early as mid-morning.

This transition will allow bands of heavy snow to develop through Southern and Central Ontario. There is also the potential for a frontal snow squall to form along the advancing cold front, producing a narrow but intense burst of snow that could rapidly deteriorate travel conditions.

**MAX WIND GUST (KM/H)** - MAP FROM WEATHERBELL

Adding to the severity of this setup will be the strong winds developing by mid-morning on Monday and continuing through the afternoon. Wind gusts of 90 to 100 km/h are possible near the shores of Lake Huron, Georgian Bay, Lake Ontario and Lake Erie, while areas farther inland could still see gusts reaching 70 to 90 km/h.

When these winds combine with intense snow squalls moving through late Monday morning, blizzard criteria will likely be met in several regions. This is especially true east of Lake Huron, including Huron, Perth, Grey and Bruce counties, as well as areas southeast of Georgian Bay near Lake Simcoe, where winds are expected to be strongest.

As the main system exits by Monday afternoon, snowfall will become increasingly driven by moisture from the lakes. This will concentrate the heaviest and most persistent snowfall within the snowbelt, particularly east of Lake Huron and around Lake Simcoe, where steady light to moderate lake effect snow will continue.

While snowfall rates during this phase may not be extreme, the combination of ongoing snow and strong winds will continue to produce near-zero visibility at times. Blizzard conditions may persist into the evening hours in the hardest hit regions despite somewhat lighter snowfall rates.

Winds will slowly begin to ease overnight into Tuesday morning, but blowing snow will remain a major issue. Gusts of 70 to 80 km/h may still occur east of Lake Huron early Tuesday, keeping travel conditions hazardous even as the most intense blizzard conditions begin to fade.

The peak period for blizzard conditions is expected from Monday morning through Monday afternoon. During this time, gusts near or above 90 km/h will combine with steady lake effect snow.

Blizzard criteria is most likely to be met around Lake Huron, including areas such as Tobermory, Wiarton, Owen Sound, Kincardine, Hanover, Goderich and Grand Bend, as well as across Simcoe County and parts of northern York and Durham regions.

What is a blizzard?

In Canada, blizzard conditions are officially defined as a combination of strong winds and blowing snow that severely reduces visibility.

Environment Canada considers blizzard criteria to be met when sustained winds or frequent gusts of at least 40 km/h combine with falling or blowing snow to reduce visibility to 400 metres or less. These conditions must persist for at least four consecutive hours to be classified as a blizzard.

It is important to note that blizzard conditions are based on visibility and wind, not snowfall amounts, meaning they can occur even with relatively light snowfall if winds are strong enough to cause widespread blowing and drifting snow.

Surrounding areas may also see periods of blizzard conditions, including London, Tillsonburg, Woodstock, Kitchener, Newmarket, Oshawa and Orillia. Confidence is slightly lower in these locations due to their distance from the core lake effect bands, but brief or localized blizzard conditions remain fairly likely.

Across Southwestern Ontario, including Windsor, Chatham and Sarnia, localized blizzard conditions are possible for a few hours Monday morning as heavier system snow moves through. Similar brief conditions could develop in the Niagara region and the outer Golden Horseshoe, where strong winds overlap with bursts of snow.

Overnight Monday into Tuesday morning, persistent snow squalls are expected to become established. One squall off Lake Huron may stretch through parts of Huron and Perth counties and at times reach into Woodstock and Brantford.

The Georgian Bay snow squall is expected to focus on the Collingwood to Barrie corridor and may occasionally extend into portions of York and Durham Region. These squalls may remain relatively locked in place through the night and morning hours, allowing snow to accumulate quickly as temperatures fall and accumulation efficiency increases.

By Tuesday afternoon, a shift in wind direction is expected to weaken the Georgian Bay squall. The Lake Huron squall will likely become dominant and gradually drift northward, stretching from Hanover through Kitchener and into the western GTA.

This northward drift is expected to continue into Tuesday evening, while a new squall may redevelop farther south, again focusing on Huron and Perth counties and extending toward Kitchener and Hamilton Tuesday night.

Although this forecast period ends Tuesday evening, snow squalls are expected to persist into Wednesday, with activity becoming more focused on Grey-Bruce. A separate forecast will be issued to cover conditions beyond Tuesday.

Given the meandering nature of the snow squalls east of Lake Huron, no single location is expected to dramatically outpace others in snowfall. Instead, widespread totals will be spread across communities such as Port Elgin, Chatsworth, Hanover, Flesherton, Kincardine, Mildmay, Minto, Point Clark, Wingham, Goderich, Listowel, Mitchell, Clinton, Exeter and Woodstock.

Snowfall totals in these areas are generally expected to range from 25 to 50 cm by the end of Tuesday. Similar totals of 25 to 50 cm are also likely for locations southeast of Georgian Bay, including Collingwood, Wasaga Beach, Barrie, Angus, Innisfil and Keswick.

Areas just outside the core lake effect zones, such as Grand Bend, London, Fergus, Arthur, Meaford, Owen Sound, Wiarton, Lion’s Head, Tobermory, Bradford and Orillia, are expected to see lower totals. These areas are generally looking at 15 to 25 cm of snow, though small shifts in wind direction could easily bring heavier snowfall into these communities.

For the remainder of Southwestern and Central Ontario, snowfall totals are expected to range from 5 to 15 cm. Most of this snow will fall early Monday with the system itself, followed by occasional lake effect snow through Tuesday.

Deep Southwestern Ontario, much of the GTA, the Niagara region and Eastern Ontario are expected to see less than 5 cm of snow overall. Despite lower accumulations, strong winds and brief bursts of snow could still lead to poor travel conditions at times.

December 13, 2025

Southern Ontario’s Never-Ending Winter Continues This Weekend as Squalls Threaten to Bring Up to 50cm of More Snow

December 13, 2025/ Brennen Perry

With a steady parade of system after system, along with lake effect snow in between, it’s certainly understandable that some parts of Southern Ontario are getting pretty fed up with all the snow. The snow continues to pile up, especially across the snowbelt regions!

It was only a few days ago that the Barrie area was slammed with intense lake effect snow, with up to 70cm reported in the hardest hit community of Angus. And that doesn’t even include what was already on the ground before this round of squalls moved through.

Regions east of Lake Huron, including Grey, Bruce, Huron and Perth counties, have also seen their fair share of snow so far this winter, with frequent lake effect events adding to an already deep snowpack.

Fortunately for snow lovers, and perhaps unfortunately for everyone else, the squalls are far from finished. The lakes remain wide open, and we are just getting into the heart of colder Arctic air. That combination will continue to provide plenty of fuel for additional rounds of lake effect snow in the coming weeks.

The next round of squalls is just around the corner, with activity expected to ramp up again as early as Saturday morning. The good news for areas that were recently hammered by the Georgian Bay squall, including Barrie and Wasaga Beach, is that you should catch a bit of a break this weekend. The bulk of the activity will focus farther north and west.

Those east of Lake Huron, including Huron, Bruce and Grey counties, are not as lucky. Lake effect snow off Lake Huron is expected to target these areas once again with repeated rounds of snow through the weekend.

This is shaping up to be a multi-day lake effect event, with squalls persisting through the weekend and possibly into Monday. Winds are expected to be somewhat unstable, which means the squalls will tend to drift around rather than remain locked over one specific area. Because of this, it’s unlikely we’ll see extreme localized totals like the 50 to 75cm that fell southwest of Barrie earlier this week.

That said, snowfall totals will still add up. The hardest hit areas, including Parry Sound, Bracebridge, Tobermory, Owen Sound, Hanover, Collingwood, Goderich and Grand Bend, can generally expect 25 to 40cm. Some pockets, particularly across Muskoka, could push closer to the 50cm mark.

The event is expected to get underway early Saturday morning as a brief southwesterly wind develops. A weak system moving through the region will become enhanced by the lakes, producing short bursts of heavy snow.

This could impact areas northeast of Georgian Bay as well as regions northeast of Lake Erie and Lake Ontario. Places like Parry Sound, North Bay, Niagara and Kingston could see a quick 5 to 10cm early Saturday morning, along with near-zero visibility at times.

As that system exits, winds will become more westerly, shifting the focus back to Georgian Bay and Lake Huron through Saturday afternoon and evening.

Current model guidance shows a fairly potent and narrow band setting up near the northern tip of the Bruce Peninsula, stretching across Georgian Bay and coming inland near Port Carling and Bracebridge. Keep in mind that even small shifts in wind direction could push the heaviest snow several dozen kilometres north or south.

Very poor to hazardous driving conditions are expected along the Highway 400 and Highway 11 corridors in this area. Highway closures are not out of the question, especially given how quickly conditions can deteriorate.

Additionally, somewhat weaker bands are also expected to develop off Lake Huron, impacting the Owen Sound to Goderich corridor. There remains uncertainty regarding exactly where these bands will set up and whether they consolidate into a more dominant squall.

Later Saturday, a subtle wind shift will cause the main Georgian Bay squall affecting Muskoka to briefly drift south into Simcoe County. This could bring a short period of heavy snow overnight Saturday to Midland, Orillia and Barrie. Accumulation here should be limited, generally around 5 to 10cm, as the squall will be moving through fairly quickly.

A similar evolution will occur east of Lake Huron, with the squall drifting from Tobermory down through the Bruce Peninsula and into southern Bruce and Grey counties overnight. This activity will continue as the squall settles farther south and west of London under a more north-northwest flow.

By Sunday morning, the strongest lake effect activity is expected to be found off Lake Huron, affecting the Grand Bend to London corridor. At this point, it appears the core of the squall should remain just west of London, impacting areas like Strathroy, though brief pushes into the city are still possible.

The Georgian Bay squall will temporarily weaken as winds become less favourable for a strong lake fetch. This should restrict activity mainly to shoreline areas near Meaford and Collingwood for a time.

That break will be short-lived. By Sunday evening, increasing winds will allow lake effect snow off Georgian Bay to intensify once again. Some models show moderate to heavy snow developing from Meaford through Collingwood and extending toward the Orangeville region overnight, before the lake effect machine is shut down by an approaching system on Monday morning.

Lake Huron squalls will continue through this time, remaining heavy at times across Huron County, Grand Bend and areas west of London. As with earlier periods, most of the heaviest snow should stay just to the west of the city.

Because the squalls will be shifting around, snowfall will be more evenly distributed across a wider area. We aren’t expecting extremely high localized totals, but many communities will still share in the heavy snowfall. By the end of the weekend, most areas east of Lake Huron and Georgian Bay could see totals ranging from 25 to 50cm.

The usual lake effect disclaimer applies. Some locations will inevitably end up just outside the heaviest bands, but the contrast should be less dramatic this time since most snowbelt areas will be impacted at some point.

The main target zones include areas east of Georgian Bay, such as Parry Sound, Rosseau, Port Carling, Bracebridge and Port Sydney, along with much of Bruce, Grey, Huron and Middlesex counties east and southeast of Lake Huron. This includes communities like Tobermory, Wiarton, Lion’s Head, Owen Sound, Meaford, Collingwood, Flesherton, Hanover, Chatsworth, Port Elgin, Kincardine, Mildmay, Point Clark, Wingham, Goderich, Clinton, Exeter, Lucan, Grand Bend and Strathroy.

Snowfall totals will drop off quickly outside of these regions, as lake effect snow remains highly localized. However, as mentioned earlier, a brief 5 to 10cm is still possible Saturday morning for parts of Niagara and the Kingston area due to lake-enhanced snow from the passing system.

For the rest of Southern Ontario, expect around 2 to 5cm from that system on Saturday, with most locations likely closer to the lower end of that range outside of the snowbelt.

December 10, 2025

Barrie Area to Be Buried in Up to 40 to 75 cm of Snow on Thursday as Arctic Air Fuels Dangerous Snow Squalls

December 10, 2025/ Brennen Perry

Snowfall from the Alberta Clipper that slid through Southern Ontario earlier on Wednesday is beginning to taper off. The system has left its mark across the region with a widespread 10 to 20cm of snow in some areas, while others saw a slushy mix.

While the clipper may be done, the snowfall story is not. As the system pulls away, it ushers in a polar blast of cold air overnight on Wednesday. This air, combined with strong northwesterly winds, will kick the lake effect snow machine back into gear off Lake Huron and Georgian Bay.

Intense snow squalls across Simcoe, Huron and Perth counties throughout Thursday are likely to create dangerous conditions. Frigid wind chills paired with near-zero visibility will make travel extremely difficult and even life-threatening if you become stranded.

The Georgian Bay squall is expected to be particularly intense. A narrow corridor from Wasaga Beach through southwest Barrie, including Angus, Innisfil and into Bradford, may see the band lock in place for more than six hours. Snowfall rates could exceed 5cm per hour.

Localized totals around the Barrie area could approach 50 to 75cm in the hardest hit pocket. Some high resolution models even suggest 100cm is not completely off the table.

East of Lake Huron, activity will be persistent from Thursday morning through the evening. The lake effect here appears more spread out rather than focused on one specific pocket. The heaviest totals are expected across Huron and Perth counties, where up to 50cm is locally possible.

As of Wednesday evening, we are already seeing some activity begin ramping up off the southeast shoreline of Lake Huron and Georgian Bay. This will continue to organize after midnight into the early hours of Thursday.

By early morning, we expect the most focused squalls to target the Goderich to London corridor off Lake Huron and the Collingwood to Bradford stretch off Georgian Bay.

Keep in mind, this is a rough idea from the models, and the exact placement can shift if the wind direction changes even slightly.

By the time the morning commute begins around 6 AM, snow squall activity will intensify as the Georgian Bay band becomes extremely narrow and focused. Some model runs have it stretching from Wasaga Beach through Angus and into the Innisfil to the Newmarket area.

There remains uncertainty in how much snow the City of Barrie itself will receive. The gradient between limited snow and a huge dumping will be very tight. The south and west ends are most likely to see major impacts, although it would not take much of a shift for the band to slide directly into the city.

The Lake Huron activity will begin to spread out with moderate snowfall covering much of Huron and Perth counties, including Goderich, Wingham, Stratford and Listowel. Because the band is more diffuse, there will not be one intense pocket as we expect with the Georgian Bay squall.

**ESTIMATED WIND CHILL** - MAP FROM WEATHERBELL

A major factor with this round of squalls that makes the situation more dangerous is the very cold wind chills. When you wake up Thursday, wind chills will make it feel like the -20s. Combined with squalls at the same time, the risk to anyone stranded on the roads increases significantly.

Aside from the cold creating hazards, it will also boost snowfall rates. Colder air produces drier, fluffier snow, which allows the same amount of moisture to create a larger volume of accumulation.

Little will change heading into the late morning as the Georgian Bay squall remains locked in place near the Barrie area. The band could edge far enough north to put the city core into the bullseye. Keswick may also be brought into the heavy snow as the band wobbles.

For the Lake Huron squall, the band may briefly become more focused as a single strong line cutting through Goderich and into Stratford and Woodstock. Depending on slight track shifts, Kitchener or Hamilton could also be affected at times.

Conditions are expected to deteriorate further into the afternoon. The Georgian Bay squall appears to strengthen with hourly snowfall rates easily exceeding 5cm and possibly pushing 10cm. At this point, the most intense pocket is shown just southwest of Barrie, with Angus being hit hardest.

The Lake Huron squall will also become more organized with an impressive fetch stretching all the way toward Lake Erie and impacting Woodstock and Norfolk.

There is significant concern for the Hwy 400 corridor during the afternoon and evening commute from just south of Barrie to roughly Aurora. This section of highway will likely become snow covered with road crews struggling to keep up with extreme snowfall rates. Combined with whiteout conditions, travel in this zone should be avoided unless absolutely necessary.

As we head into the evening and just past midnight, the squalls will retreat closer to the lakeshores as winds weaken and moisture supply cuts off. This will lead to activity tapering to lake effect flurries overnight into Friday morning.

As always with snow squalls, snowfall forecasts should be taken with a large grain of salt. While models are in good agreement on placement and intensity, nothing is guaranteed as conditions need to align perfectly.

With that being said, we believe the hardest hit zone will be along the southeastern Georgian Bay shoreline from Wasaga Beach through Angus and into northern York Region. Barrie sits right on the edge but could easily end up inside the bullseye. Snowfall totals here are likely to exceed 40cm and may approach 75cm. Around Angus is where models show the strongest signal.

A tight gradient will set up with the north and east sides of Barrie, along with Keswick, Bradford and Collingwood, likely seeing 25 to 40cm of snow.

East of Lake Huron including Kincardine, Minto, Point Clark, Wingham, Listowel, Mitchell, Stratford, Exeter and Goderich, totals of 25 to 40cm are expected. Localized amounts up to 55cm are possible if a squall locks in place for several hours.

Totals of 15 to 25cm are possible for Midland and into central York Region including Newmarket and Aurora as well as Durham Region around Uxbridge. These areas will see occasional bursts of heavy snow near the edge of the main bands.

Southern Bruce and Grey counties along with Wellington County including Arthur and Oxford County may also see 15 to 25cm but totals depend on how far inland the bands extend.

Between 5 and 15cm is possible across the rest of York and Durham Region as well as northern Simcoe County including Orillia, Owen Sound, Shelburne, Fergus, Kitchener, Brantford and London. These locations sit farther from the core activity so most will see closer to 5cm with higher amounts only if a band stretches farther inland.

Less than 5cm is expected outside the snowbelt regions including Eastern Ontario, Deep Southwestern Ontario and the Golden Horseshoe.

December 03, 2025

Brief, Intense Snow Squalls Return to Southern Ontario’s Snowbelt on Thursday With Up to 20 to 50cm Expected

December 03, 2025/ Brennen Perry

Intense but brief snow squalls are expected to return to parts of the snowbelt region around Lake Huron and Georgian Bay early Thursday morning with the arrival of a blast of brisk Arctic air. These squalls have the potential to bring heavy snowfall and near-zero visibility in the hardest hit areas.

Conditions are certainly ripe for more extreme, long-lasting squalls; However, the latest model data suggests this round will be cut short as shifting winds prevent the bands from locking in place for any prolonged period of time.

Snow squalls developing off Lake Huron will follow a west-northwest flow with the most intense activity aimed at the northeastern shoreline, which includes much of Grey Bruce. Another band off Georgian Bay will have a less steady flow, making the Lake Huron squall the stronger and more focused of the two.

This band is expected to remain mostly stationary through much of the morning and possibly into the early afternoon before slowly weakening later in the day. Hazardous conditions are expected in this zone with complete whiteouts, blowing snow and rapid snowfall rates of 4 to 6cm per hour.

The hardest hit areas are likely to be around Port Elgin, Kincardine and Owen Sound where a band could set up early and barely move until the afternoon as winds ease and the squall dissipates. The reach of this band may stretch inland into parts of Grey County at times, including Meaford, Chatsworth, Flesherton and Hanover. Some areas could be digging out from significant totals by the end of the day.

Meanwhile, over Georgian Bay, shifting wind directions will make things much less predictable. The squall here will likely spread snowfall over a wider area rather than focusing on one region, mainly due to the flow swinging from westerly to northwesterly throughout the day.

It will likely begin with a westerly flow during the early morning, which would start the band in southern Muskoka, including MacTier, Bala, Bracebridge and Gravenhurst. It may also extend at times into southern Haliburton and northern Kawartha Lakes.

As winds turn more northwesterly, the band will slide down along the Hwy 400 and 11 corridor into northern Simcoe County, affecting Midland, Orillia and Washago. Travel in this region during the morning and early afternoon should be avoided if possible, as conditions will be quite poor.

There is still some uncertainty regarding the intensity of this Georgian Bay band, as shifting winds tend to weaken squalls and make them less organized. If it becomes even briefly stationary, that would likely be the period where snowfall intensifies.

How long the band can hold together before winds lock into a true northwest flow will determine totals for areas such as Barrie and the southern portions of Kawartha Lakes. By the early afternoon, the squall will have sunk into Wasaga, Oro and Barrie, but once the wind shift finalizes, the band will quickly lose its structure and begin to fizzle out.

If the squall lasts only into the mid-afternoon, Barrie may end up closer to 10cm. If it somehow holds into the evening, totals closer to 30cm would be possible.

All snow squall activity is expected to taper off by Thursday evening across Southern Ontario, although some light snow may linger overnight into Friday morning in areas closer to the lakes.

For Northern Ontario, snow squalls off the southeastern shoreline of Lake Superior will develop overnight and persist through much of Thursday. Sault Ste. Marie and the Wawa region may pick up 30 to 50cm by the end of the day. That lake effect activity is expected to weaken Thursday evening as a weak system shifts the wind direction.

Snowfall totals will vary widely due to ongoing uncertainty about the exact placement and duration of the bands. Confidence is highest that the Lake Huron squall will remain more focused compared to the Georgian Bay band.

As a result, the hotspot includes Port Elgin, Owen Sound, Hanover and Chatsworth, where 30 to 50cm is expected, with some models even hinting at localized pockets approaching 60cm.

The rest of Grey and Bruce counties are looking at 15 to 30cm, although totals may vary significantly depending on how far inland the squall extends and whether it drifts south into northern Huron and Perth counties.

Areas farther south and inland, including the rest of Huron and Perth counties, Wellington, Dufferin and Collingwood can expect around 5 to 15cm, but there is still a chance for much lower amounts if the band does not stretch that far.

A large zone along the Hwy 400 and 11 corridor from MacTier and Gravenhurst in the north to Barrie in the south, including Midland, Washago, Orillia and Wasaga, is expected to see the highest totals from the Georgian Bay squall.

At this point, 15 to 30cm appears likely, although localized totals up to 40cm are possible should the squall stall for any period of time. If that occurs, the most probable region for this is somewhere between Midland and Orillia.

The rest of Muskoka, Parry Sound, Haliburton, Kawartha Lakes and northern York and Durham regions can expect between 5 and 15cm, depending heavily on how far inland the Georgian Bay squall is able to stretch.

Elsewhere across Southern Ontario, less than 5cm is expected by the end of Thursday.

November 26, 2025

Dangerous Snow Squalls Target Southern Ontario’s Snowbelt Starting Thursday With Up to 75cm of Snow Possible

November 26, 2025/ Brennen Perry

Confidence continues to grow in what is shaping up to be a potentially dangerous snow squall event for regions east of Lake Huron and southeast of Georgian Bay as we wrap up the week.

Temperatures are expected to drop sharply overnight Wednesday, which will help kick the lake effect snow machine into gear as early as Thursday morning.

At first, the activity should be fairly limited. Scattered pockets of lake effect snow are expected to develop east of Lake Huron and Georgian Bay as a westerly wind pattern holds through the morning. Impacts will be minor at this stage, but this early activity will set the stage for a much more intense setup later in the day.

Rapid changes are expected by late Thursday morning and especially into the afternoon. This is when more organized squalls will begin to form.

The worst conditions are expected to develop late Thursday and last into Friday morning. A brisk northwesterly wind will allow narrow but powerful bands of snow to strengthen off both Lake Huron and Georgian Bay. These bands will be capable of producing snowfall rates near 5 to 10 cm per hour at times, along with near-zero visibility.

Travel will likely become extremely difficult through the hardest hit regions. Strong winds will create blowing snow and possibly even brief blizzard conditions. Road closures are possible, and anyone with non-essential travel plans should consider postponing. School bus cancellations appear likely for Friday, and there is even some potential for cancellations on Thursday, depending on how quickly conditions deteriorate.

The main snow squall activity is expected to taper off throughout the day on Friday, although some scattered bands could linger into Saturday. By the end of the day Friday, some areas east of Lake Huron, such as Goderich, Kincardine and Stratford, may be digging out from more than 40 cm of snow. Other parts of the snowbelt may see anywhere from 10 to 40 cm, depending on how close they are to the core of the activity.

As mentioned earlier, Thursday morning will start with some light to moderate activity east of Lake Huron and Georgian Bay. This includes Grey Bruce, Parry Sound and Muskoka.

Impacts should be limited at first since the snow will be fairly light, but Environment Canada currently has a snow squall watch in effect for this entire region due to what will likely unfold later in the day.

Conditions will escalate quickly heading into the late morning and afternoon as scattered flurries begin organizing into more defined bands. We expect a fairly long squall to develop over Lake Huron, cross the Bruce Peninsula and come onshore east of Georgian Bay. This could bring a few hours of heavy snow to the Muskoka region.

Additional pockets of lake effect snow may also fire up further south off Lake Huron, affecting areas like Goderich, Hanover, Stratford and Kitchener.

That Georgian Bay squall is expected to gradually sink southward as the wind shifts from westerly to northwesterly. This will cause a swath of intense snow to drift across the Highway 11 and 400 corridor between Bracebridge and MacTier, down toward Barrie.

A few hours of rapid whiteout conditions are possible during the afternoon. Even though temperatures may hover near the freezing mark, which slows accumulation, visibility will still be extremely poor and blowing snow will create dangerous travel conditions.

Conditions will worsen significantly into the evening as the squall drifts far enough south to draw its full moisture supply from Lake Huron instead of Georgian Bay. This new orientation will allow the band to tap into a longer stretch of open water, which increases its intensity.

At this point, several intense bands could stretch inland between Kincardine and Goderich and reach as far east as Kitchener and even the western GTA at times.

There is still some uncertainty in how these bands will align. A slight shift in wind direction can cause a squall to lock in place further north or drift south. This will dramatically affect who sees the heaviest snow. Regardless, conditions will be poor even in areas that are not directly underneath a streamer due to the blowing snow.

Within the core of the squalls, snowfall rates of 5 to 10 cm per hour will be possible. Thundersnow and lightning cannot be ruled out, given the strength of the setup.

Georgian Bay will see a brief lull with lighter pockets of snow affecting the South Muskoka to Simcoe County corridor. This break will be short-lived as winds shift yet again heading into the overnight hours.

The most dangerous conditions are likely overnight Thursday into Friday morning. A very intense squall off Lake Huron is expected to set up somewhere between Goderich and Kincardine and stretch inland toward regions between Kitchener and London.

There is still uncertainty about the exact placement. Even a tiny shift in wind direction could pin this band farther north or push it farther south. At times, it may also extend into Hamilton and the Niagara region with quick bursts of heavy snow and whiteouts.

Southeast of Georgian Bay, more organized bands are likely to develop from Barrie into Kawartha Lakes. Some of this activity may also clip the northern GTA, including York and Durham. The Georgian Bay squall will likely be weaker than the Lake Huron band, but model trends have strengthened it slightly in the latest data. Peak snowfall rates will likely sit around 3 to 6 cm per hour in the strongest areas.

Temperatures will plunge well below freezing overnight which will help snow accumulate far more efficiently.

Most model data suggests that the lake effect bands will remain locked in place through Friday morning, although the intensity may gradually decrease during the afternoon as winds begin to ease. Snow squalls could continue into Saturday, but confidence drops for the weekend pattern since the bands may become more fragmented and less organized.

As always with lake effect snow, exact totals are extremely difficult to predict. These events can produce huge differences over very short distances. One community could pick up 50 cm while another, only a few kilometres away, sees barely any accumulation.

Even with this uncertainty, the most consistent model signal points toward a high-impact zone east of Lake Huron, picking up a general 40 to 75 cm of snow by Friday evening. This includes Goderich, Point Clark, Kincardine, Mildmay, Wingham, Clinton, Mitchell, Listowel and Stratford.

Localized totals near 100 cm cannot be ruled out, although these would be isolated pockets rather than widespread amounts.

A wider zone east of Lake Huron that stretches into the Kitchener area has the potential to see 20 to 40 cm of snowfall accumulation.

For Georgian Bay, the squall should be weaker than the Lake Huron band. We are going with 20 to 40 cm for regions like Collingwood, Wasaga Beach, Midland, Orillia, Barrie, Innisfil, Angus and Keswick. This may end up being a slight overestimate if the squall fails to organize as we saw in the last event, which significantly underperformed.

Muskoka, Parry Sound, Kawartha Lakes and parts of the eastern GTA may see 10 to 20 cm depending on how far the bands push inland.

Less than 10 cm is expected for the rest of Southern Ontario, including Eastern Ontario, the Golden Horseshoe and deep Southwestern Ontario, since they will be far enough removed from the main lake effect activity.

November 25, 2025

Winter Storm Targets Northern Ontario This Week as Intense Snow Squalls Line Up for Southern Ontario Starting Thursday

November 25, 2025/ Brennen Perry

A powerful system will sweep through the Great Lakes region this week, bringing a major winter storm to Northern Ontario and setting the stage for a significant snow squall event across Southern Ontario later in the week.

Across Northern Ontario, snowfall will begin to move into regions east of Lake Superior by late Tuesday. Light snow will start from Wawa through Timmins, gradually expanding north and west. Through the overnight hours into Wednesday morning, the system will push into Thunder Bay, Kapuskasing and surrounding communities.

The worst conditions are expected throughout the day on Wednesday. Winds will gust between 40 and 60 km/h, and when combined with heavy snowfall rates, visibility will deteriorate quickly. Blowing snow will be widespread across Northeastern Ontario and conditions may even reach blizzard levels at times.

Treacherous travel conditions will continue into Wednesday night and persist through Thursday morning as the storm deepens. Snowfall intensity will gradually ease later on Thursday, but steady snow will continue as the system stalls over Quebec. This will push long lasting bands of precipitation back into Northeastern Ontario, keeping snow going until early Friday morning.

By the time the storm fully exits, a wide swath of Northeastern Ontario is expected to receive 20 to 50 cm of snow, with localized totals possibly exceeding that. The heaviest totals are expected from Marathon through Kapuskasing, Cochrane, Timmins, and Temiskaming Shores, Wawa, Hearst and Chapleau. Snowfall totals here will range from 30 to 50cm with possibly as much as 60cm in localized pockets.

While Northern Ontario deals with the winter storm, Southern Ontario will be on the warm side of the system on Tuesday and Wednesday. Many areas will flirt with the double digits, especially in Southwestern Ontario. Scattered showers will develop early Tuesday with light rainfall amounts of roughly 5 to 10 mm.

By late Wednesday, though, the pattern begins to shift as cold air wraps in behind the departing system. Temperatures will drop quickly, and any lingering precipitation will change to wet snow by Wednesday evening.

This colder air will set the stage for lake effect snow to fire up. With a westerly wind overnight on Wednesday, snow squalls may begin to develop off Lake Huron and Georgian Bay.

These early bands could bring bursts of heavy snow to Grey Bruce, Parry Sound and Muskoka through Thursday afternoon, although the exact intensity remains uncertain as the higher resolution models are just entering range and showing stronger signals than the medium range guidance.

By late Thursday, winds will shift to a northwest flow. Temperatures will drop further into the negatives and this will allow squalls to strengthen. The Georgian Bay band is expected to sink south into Simcoe County and then extend into Kawartha Lakes and Peterborough.

At the same time, the Lake Huron band will slide south into Huron County and stretch toward Kitchener and the western GTA. Some early guidance even hints that this band could link up with the flow off Lake Superior, which can enhance snowfall rates.

Heading into Friday, it is still too early to give precise band placement. Current thinking suggests the northwest flow will hold through much of the day before winds start easing over the weekend. If that happens, squalls could remain active for an extended period.

While details can still shift, we are beginning to narrow down regions with the highest risk of heavy snowfall starting Thursday morning and continuing into Friday evening. Squalls will shift around at times, so snowfall will not be constant, but those under the core of the bands could see snowfall rates approaching 5 to 10 cm per hour. It will not take long for the snow to accumulate.

At this stage, exact totals are not possible to predict for Southern Ontario. However, some regions could easily see 25 to 50 cm by Friday night, with the potential for higher localized totals once high-resolution data comes into range.

For Lake Huron, our current focus areas include Kincardine, Goderich, Hanover, Kitchener, Hamilton and Orangeville.

For Georgian Bay, our primary targets include Midland, Barrie, Gravenhurst, Bracebridge, Orillia, Kawartha Lakes and Peterborough.

Anyone living in or near these regions should be prepared for dangerous travel conditions beginning Thursday. School bus cancellations are likely for some regions, and road closures are possible if squalls remain intense or stationary.

November 15, 2025

Snow Squalls Take Aim at London, Barrie and Northern GTA on Sunday With Up to 25-50cm of Snow Possible

November 15, 2025/ Brennen Perry

We enjoyed a brief break from the wintry weather on Saturday as temperatures soared into the double digits across much of Southern Ontario. The exception was Eastern Ontario, where the Ottawa Valley dealt with hours of freezing rain.

But that warm spell is going to be short-lived. Cooler air returns overnight into Sunday, and temperatures will slide back below the freezing mark. Once that happens, the lake effect snow machine will fire up again for the next couple of days.

And no, it isn’t déjà vu. The target zone for this round of squalls will look very similar to last week’s event, but the focus shifts slightly east. That puts areas like London, Barrie and even the Northern GTA, including York Region, in line to be hit hard.

By the time the squalls wind down on Monday, the hardest hit spots could be digging out from more than 25cm, with the potential for very localized pockets of 50cm.

We expect the snow squall activity to begin ramping up late Sunday morning. As temperatures fall, lake effect rain bands will flip over to snow off the southeast shoreline of Lake Huron and Georgian Bay.

While the changeover happens in the morning, ground temperatures may stay just above freezing for several hours. This means the first few hours of snow could melt on contact. Accumulation will start later in the day once temperatures reach the freezing mark.

Even before the snow begins to stick, visibility will drop quickly. Those in the affected areas should expect sudden whiteouts and dangerous driving conditions.

**Hourly snowfall rate (cm)** - MAP FROM WEATHERBELL

By the dinner hour, the squalls will become much more organized. Snowfall rates from the Lake Huron band could rise to 5cm per hour. This main band is expected to extend from Lake Huron through Goderich and southern Huron County into the London region.

Additional squall activity will form southeast of Georgian Bay, running from the shoreline through Barrie and Angus and into Newmarket and Durham. This band looks weaker than the Lake Huron squall at first, but could still deliver rates of 2 to 4cm per hour.

The worst conditions are likely around midnight. The Lake Huron band is expected to lock onto London, bringing intense snow and rapid accumulation of 6 to 8cm per hour.

The Georgian Bay squall will also strengthen, sliding south of Barrie and focusing on Angus, Bradford and Newmarket. Some signals show it reaching into the Eastern GTA, including Scarborough, Ajax and Oshawa.

These squalls should remain mostly stationary overnight, although minor drifting is possible. As temperatures fall several degrees below freezing, expect snow to pile up quickly.

By mid-morning Monday, the bands will begin to weaken as winds shift more westerly. Some lake effect flurries could linger east of Lake Huron into Grey Bruce, but they are not expected to be very organized. Everything should taper off by late Monday.

Snow squall forecasting always comes with big caveats. The bands are extremely narrow, which means the difference between 50cm and almost nothing can be only a few dozen kilometres.

This is why we provide a broad range. They help capture that uncertainty, but they are not a guarantee. With this event, the bands appear very intense but also very narrow, which means gradients will be sharp.

Based on the latest data, we expect the hardest hit areas from the Lake Huron squall to include Goderich, Clinton, Lucan, Exeter, Mitchell and London. Snowfall totals here could range from 25 to 50cm, with the chance that someone ends up over 50cm in a very localized spot.

Surrounding regions, including Grand Bend, Tillsonburg, Stratford, Wingham, and Point Clark, could see 15 to 25cm.

Further east into Grey Bruce and Dufferin County, we are expecting 5 to 15cm mainly on Monday as the lake effect shifts northward.

The Georgian Bay band looks even narrower than the Lake Huron band. A small corridor stretching from Collingwood through Angus and into Innisfil could see 25 to 35cm, with a chance of 50cm if the band really intensifies.

The City of Barrie is right on the edge. A small shift north or south would bring very different results. For now, the highest totals look likely in the south end of the city with 15 to 30cm. The north end may be closer to 10 to 20cm.

Substantial totals may also extend into the Northern GTA, including Bradford, Newmarket and Aurora. Totals along the Highway 400 and 404 corridor could range from 15 to 30cm.

Across the east end of Toronto and Durham, including Ajax, Pickering and Oshawa, occasional heavy bursts may bring 5 to 10cm.

The rest of Southern Ontario should see less than 5cm of snow by Monday from the lake effect.

November 15, 2025

All the Seasons in One Weekend for Southern Ontario as Freezing Rain, Thunderstorms and Snow Squalls Line Up

November 15, 2025/ Brennen Perry

There is really only one way to describe what November has been like across Southern Ontario when it comes to the weather: a roller coaster.

Last weekend brought our first widespread snowfall event of the season. That was quickly followed by intense snow squalls that buried parts of the Lake Huron shoreline with more than 50 cm of snow early this week.

That seasonal whiplash continues this weekend as a clear battle sets up between cold, wintery air and much milder fall-like conditions. Eastern Ontario, especially around the Ottawa Valley, will stay on the cold side with a risk of prolonged freezing rain throughout the day on Saturday.

Southwestern Ontario and the Golden Horseshoe will see a completely different story. Temperatures are set to rise into the double digits, and there is even a risk of thunderstorms on Saturday. Some of the warmest pockets around Windsor could briefly flirt with the 20s for a few hours.

By late Saturday, a sharp cold front will sweep through the region. This will send temperatures plunging again heading into Sunday, settling the battle in favour of the colder air. As this cold push arrives, the lake effect snow machine is expected to roar back to life over both Georgian Bay and Lake Huron.

We expect a frosty start to Saturday morning for most of Southern Ontario. Deep Southwestern Ontario will be the main exception as milder air starts to slide in early. Most areas should wake up close to the freezing mark. Deep Southwestern Ontario will already be climbing through the mid single digits.

By noon, Deep Southwestern Ontario should reach the double digits. Further northeast into the rest of Southwestern Ontario, the Golden Horseshoe and parts of Central Ontario, temperatures will range from the low to mid single digits. The Ottawa Valley will remain near the freezing mark well into the afternoon as the surge of mild air stalls just to the southwest.

A developing system will start to spread heavy precipitation into Southern Ontario late Saturday morning or early afternoon. For most areas, temperatures will be warm enough for rain to be the dominant precipitation type. There’s even the risk of a thunderstorm!

Over the Ottawa Valley, however, we expect patchy freezing rain to form as temperatures linger stubbornly near the freezing mark.

Model guidance is not fully aligned on how warm the air will get in that region. Even a small shift of one or two degrees will change how long the freezing rain lasts and how much ice is able to accrete. This is one of the key uncertainties for Saturday.

Through Saturday evening, temperatures will continue climbing across much of Southwestern Ontario. Cities like London, Kitchener and Hamilton are expected to reach the double digits.

One important note is that daytime highs in many areas will actually be reached late in the evening instead of during the normal warmest part of the day!

Meanwhile, that pocket of near-freezing air over the Ottawa Valley is expected to hold on into the evening, which could allow several more hours of freezing rain.

As the system pulls east overnight Saturday, colder air will sweep in behind it. Temperatures will tumble through Sunday morning, switching any lingering precipitation to wet flurries by the time you wake up.

Behind the front, bands of lake effect snow will begin developing off Lake Huron and Georgian Bay early Sunday. These bands look messy and disorganized through much of the day, although localized totals of 10 to 20 cm are possible.

By late Sunday, more focused and intense squalls could form, especially around the London region off Lake Huron. These squalls may continue into Monday and could lead to localized 20+ cm totals.

We will have a more detailed, dedicated lake effect forecast released soon.

When it comes to freezing rain accretion, there are several variables that could reduce or increase the amount of ice that actually builds up. This is a very temperature-sensitive event.

The heaviest icing is expected directly along the Quebec border and into the Hawkesbury region. Models show the potential for over 10 mm of freezing rain, but it is unclear how much of that will be able to stick. Heavy precipitation rates could limit the amount of ice that accumulates, and temperatures will sit very close to the freezing mark for much of the event.

Given all of this, we are going with a general 5 to 10 mm of icing for the hardest hit areas. If temperatures are even slightly warmer than expected, accretion could end up lower. This is certainly enough to lead to localized power outages and icy roads.

For the City of Ottawa, they sit right on the dividing line between lighter icing and heavy icing. We have placed them in the 2 to 5 mm range, but they could see locally up to 7 mm if the cold air becomes more stubborn than currently forecast.

Outside of the Ottawa Valley, expect minimal icing. Areas such as Bancroft, Cloyne, Perth, Carleton Place and Cornwall may see an hour or two of freezing rain before changing over to rain.

November 10, 2025

Snow Squalls Could Bury Parts of Southern Ontario’s Snowbelt in Up to 50cm of Snow Early This Week

November 10, 2025/ Brennen Perry

As much of Southern Ontario cleans up after our first widespread snowfall of the season, Mother Nature is showing no signs of slowing down. The lake effect snow machine is roaring to life over Lake Huron and Georgian Bay as we kick off the second week of November.

Snow squalls have already developed south of Lake Huron late Sunday evening and are expected to strengthen through the night. We’re also anticipating some squall development along the southern shoreline of Georgian Bay, which should organize by Monday afternoon or evening.

Two main regions are likely to see the most intense activity. The first stretches between Sarnia and London, while the second includes areas south of Georgian Bay from Blue Mountain and Meaford toward the west of Barrie. Both zones could see heavy snow squalls lasting through to Tuesday morning.

While snowfall totals will vary significantly across short distances, confidence is increasing that the hardest hit areas could see as much as 25 to 50cm by the time the squalls taper off on Tuesday. Localized pockets may even exceed 50cm, depending on where the heaviest bands set up.

Road conditions are expected to deteriorate quickly in these regions, with road and highway closures likely late Monday and into early Tuesday when the most intense squalls occur. Travel should be avoided unless absolutely necessary, as these bands can produce sudden whiteouts, making it nearly impossible to see the road ahead.

**ESTIMATED AIR TEMPS AROUND 1.5KM ABOVE GROUND** - MAP FROM WEATHERBELL

This setup is being fueled by a rare November appearance of a mini “Polar Vortex” which is pulling a blast of Arctic air into Southern Ontario. This cold air is flooding the upper levels of the atmosphere and setting the stage for intense lake effect activity.

To put it simply, when forecasters talk about 850mb temperatures, we’re referring to the air temperature roughly 1.5 kilometres above the ground. This level helps forecasters understand how cold the air mass is higher up in the atmosphere, which is critical for predicting lake effect snow.

Over the next few days, 850mb temperatures are expected to plunge into the negative teens. Lake effect snow forms when there’s a large temperature difference between the lake surface and the air above it, generally 13°C or greater. With upper air temperatures between -10°C and -15°C and lake temperatures still above 10°C, that difference is more than 20°C, creating ideal conditions for lake effect snow to thrive.

As of midnight, snow has already developed off the southern shores of Lake Huron, impacting the Sarnia region. So far, the bands have been disorganized and spread out, but that’s expected to change by late Monday morning as a stronger, more focused squall forms somewhere between London and Sarnia.

While the exact placement remains uncertain, areas near Petrolia and Strathroy appear most likely to be in the direct path. The band will likely shift through the day as wind directions fluctuate, leading to varying snow intensities across nearby towns.

By Monday evening, things will really start to ramp up. The main squall off Lake Huron will likely push inland, with a more northwesterly wind direction steering it toward Grand Bend, Goderich and potentially the western edges of London. It’s still unclear if the squall will reach directly into London or remain just outside the city, but if it does, the heaviest snowfall will likely fall on the west side.

Meanwhile, snow squalls are expected to organize over Georgian Bay with heavy snow bands developing between Owen Sound and Barrie. There’s still some disagreement among models, with some focusing more on Wasaga Beach and Barrie while others favour a southern shoreline setup.

An interesting twist could occur if these Georgian Bay bands extend far enough inland to be enhanced by Lake Ontario. In that case, snow could reach into the western GTA and even the Niagara region, leading to sudden bursts of heavy snow if everything aligns.

This lake effect activity is expected to persist overnight and into Tuesday morning, though the Georgian Bay bands should weaken slightly around sunrise. West of London, however, heavy snow could continue well into Tuesday morning before breaking apart as conditions become less favourable later in the day.

As always with lake effect snow, totals are extremely difficult to pinpoint. These narrow bands can stay locked over one community for hours while completely missing another just a few kilometres away. One person may end up shovelling half a metre of snow while someone nearby barely sees a dusting.

That said, two areas consistently stand out across the latest model runs. One includes Lambton Shores, Grand Bend and Strathroy, while the other covers the southern Georgian Bay shoreline and higher terrain around Blue Mountain. These regions could see totals ranging from 25 to 50cm by Tuesday.

Surrounding communities such as Petrolia, Thamesville, St. Thomas and Lucan, along with Orangeville, Shelburne and Flesherton, are more likely to see 15 to 25cm.

Both London and Barrie sit right on the edge between lighter and heavier accumulations. We currently have them in the 5 to 15cm or 15 to 25cm zones, depending on how far east the snow squalls extend.

Finally, the Niagara region remains uncertain. If the Georgian Bay squalls stretch far enough inland and connect with Lake Ontario, parts of the region could pick up over 15cm of additional snow.

Outside of these snowbelt regions, impacts will be much less significant. A few flurries and brief bursts of snow are possible as the squalls wobble, but most areas outside the direct lake effect zones should remain relatively calm through Tuesday.

November 08, 2025

Snowy Sunday Sweeps Into Southern Ontario With First Widespread Snowfall of the Season

November 08, 2025/ Brennen Perry

While there has been a lot of uncertainty surrounding Southern Ontario’s first widespread snowfall event of the season, we’re finally starting to get a clearer picture of what will unfold on Sunday. After several model shifts over the past few days, the latest data is now coming into better alignment, giving us a more confident idea of how this system will behave.

A developing low-pressure system is expected to move in from the southwest late Saturday night, tracking across areas near Lake Erie through the day on Sunday. As it does, it will bring a broad swath of snow stretching from Windsor through the Golden Horseshoe and into Eastern Ontario. Snow is expected to last much of the day before gradually tapering off overnight.

At this stage, snowfall totals are expected to vary quite a bit across the region. The exact placement of the heaviest snow bands remains uncertain, and surface conditions will also play a big role. Since the ground is still relatively warm, some of the early snowfall may melt on contact before it can begin to accumulate, especially on roads and sidewalks.

In general, by Monday morning, snowfall totals are expected to range from around 5 to 10 cm across the Golden Horseshoe and into Eastern Ontario. Within those areas, localized pockets, particularly in Eastern Ontario, could pick up as much as 15 to 20 cm according to the latest model runs. Further north and west, across Central and Southwestern Ontario, amounts will be lower with less than 5 cm expected in most spots.

As the system departs, colder air will pour into Southern Ontario late Sunday night, sending temperatures well below freezing. Any slushy snow or water on roads, sidewalks, and driveways will freeze quickly overnight, which could create slick conditions for the Monday morning commute. Drivers should be prepared for icy patches, and there’s a decent chance of school bus cancellations in areas that see higher snowfall totals.

The colder air will also fire up the lake effect snow machine early next week. Model guidance suggests that an intense but narrow band of snow could form southeast of Lake Huron late Monday and continue into Tuesday. This could impact communities such as Grand Bend and London, where local snowfall totals could exceed 25 cm if the band remains stationary for an extended period.

For timing, snow is expected to begin in Deep Southwestern Ontario shortly after midnight. Around Windsor and Chatham, it may even start as rain before transitioning to snow as temperatures drop closer to dawn.

By late Sunday morning, the snow will have spread into the Golden Horseshoe, becoming heavier through the afternoon. In Eastern Ontario, snow will likely begin around Kingston early in the morning and reach the Ottawa area by midday.

The heaviest snowfall rates across the Golden Horseshoe are expected from early to mid-afternoon, with some models projecting bursts of 2 to 4 cm per hour at times before tapering off toward the evening.

For Eastern Ontario, steady snow will continue through the afternoon, peaking after dinner before easing into scattered flurries overnight. With that timing, school bus cancellations are quite possible for parts of Eastern Ontario on Monday.

There are also some indications that freezing rain or ice pellets may mix in along the international border Sunday evening. Areas such as Kingston, Brockville, and Cornwall are most at risk for this brief mix, which could add an extra layer of slickness to untreated surfaces.

While there is still some disagreement among the models on exactly where the heaviest snow will fall, the general expectation remains 5 to 10 cm along the Golden Horseshoe and into Eastern Ontario, with some locally higher amounts near 15 cm.

We’ve outlined portions of Eastern Ontario and the higher elevations of the Niagara region on our map with a dotted zone, representing areas that could overachieve and see closer to 20 cm. However, that outcome is far from certain.

Keep in mind that this is the first significant snowfall of the season, and with ground temperatures still above freezing, actual accumulation could vary from one street to the next. Some areas may see a quick coating, while others struggle to hold the snow through the day, especially near the lakeshores.

Elsewhere, Southwestern Ontario and much of Central Ontario should see lighter amounts, generally only a few centimetres, with some localized areas possibly reaching up to 8 cm. Regions like Grey-Bruce and the northern parts of Central Ontario will likely miss out on the heaviest snow this time, but that may not last long as lake effect activity ramps up early next week.

As higher-resolution models continue to come into range, we’re getting a clearer idea of what the first snow squall event of the season could look like. Current projections suggest activity will develop on Monday, with a more organized squall forming by the evening.

This band may set up somewhere between Grand Bend and Kettle Point, extending inland, likely just west of the City of London. Additional bands may also develop off Georgian Bay, impacting areas around Meaford and Collingwood.

Communities caught under these narrow squalls could see impressive snowfall totals, while just a few kilometers away, grass may still be visible. We’ll continue to refine the details as the event approaches and will have a more specific forecast on who could see the most snow closer to Monday.

Overall, this marks the true start of the winter season across Southern Ontario, with several systems and lake effect events lining up behind this one. It’s a good time to check that your winter tires are ready, snow shovels are handy, and morning routines include a few extra minutes to clear off your car. Winter is here to stay.

February 17, 2025

Snow Squalls Target the Grey-Bruce and Barrie Area Again With Locally Up to 50-100cm of Snow by Tuesday

February 17, 2025/ Brennen Perry

Snow squalls are expected to become well-organized and intensify by Monday morning. One squall off Lake Huron will target southern Grey-Bruce, with periods of intense snowfall throughout the day. Thundersnow is even a possibility in this area.

Another squall will develop off the southeast shoreline of Georgian Bay, impacting parts of southern Simcoe County, including Wasaga Beach, Barrie, Angus, Innisfil, and Keswick.

These squalls will persist into the afternoon, shifting at times. The northern squall could push into Wiarton, extend across Georgian Bay, and come onshore near Barrie. Meanwhile, the southern squall off Lake Huron will stretch from Kincardine to Hanover and could push far inland, periodically bringing heavy snow into parts of the GTA.

By Monday night into Tuesday morning, the Lake Huron squall is expected to stall over southern Grey-Bruce, potentially leading to extreme snowfall accumulation. Wherever this band locks in, snowfall rates could reach an incredible 5-10 cm per hour. Some models suggest this squall could remain in place until Tuesday evening, somewhere between Owen Sound and Hanover.

The Georgian Bay squall may weaken somewhat after midnight but could persist into Tuesday. All snow squall activity should fizzle out by early Wednesday morning.

Projected Snowfall Totals:

Localized amounts near 100 cm are possible in Grey-Bruce, with hotspots likely near Port Elgin, Hanover, Chatsworth, and Flesherton. Not everyone in this zone will see these totals, but some areas will get buried.
25 to 50 cm is likely across the rest of Grey and Bruce counties, extending into northern Huron and Perth counties. This also includes areas along the southeastern shoreline of Georgian Bay, such as Collingwood, Wasaga Beach, and Barrie.
5 to 15 cm could extend into Kitchener, Guelph, Durham, and York as occasional bursts of heavy snow push outside the core snowbelt region.
The GTA may see light snow at times but is unlikely to receive more than 5 cm over the next two days.

Aside from the snow, we’re starting the week on a much colder note. If you’re heading outside for Family Day, be sure to bundle up—wind chills in the -20s are expected on Monday.

Stay safe and stay warm!

February 13, 2025

Will It Ever End? Squalls Could Bring Up to Another 40cm of Snow by the End of Friday to Parts of Southern Ontario

February 13, 2025/ Brennen Perry

Are you enjoying winter yet, Ontario? ❄️ It feels like we've been stuck in an endless cycle of snow, with relentless snow squalls hammering the snowbelt regions.

Even outside the snowbelts, much of Southern Ontario joined in this week as a major winter storm dumped over 20 cm of snow across the region overnight into Thursday morning.

And the snowy pattern isn’t letting up anytime soon. More lake effect snow is on the way to end the week, followed by a potentially significant snowstorm this weekend.

The lake effect machine is expected to fire back up Thursday evening, becoming more organized overnight into Friday morning. Current indications suggest a strong snow squall will develop, targeting the Bruce Peninsula and stretching into parts of Simcoe County.

While squall activity should begin to wind down by Friday afternoon, areas that have already been hit hard this season—such as Orillia, Midland, Wiarton, Lion’s Head, and Tobermory—could see another 15 to 25 cm of snow. If the squall locks into place for an extended period, localized totals of up to 40 cm are possible.

**HOURLY SNOWFALL RATE/intensity** - MAP FROM WEATHERBELL

As of early Thursday evening, bands of lake effect snow are already forming off Lake Huron and Georgian Bay. These will continue to shift around throughout the evening, delivering bursts of heavy snowfall to different areas.

Right now, it looks like the heaviest snowfall will be concentrated across the Bruce Peninsula and along the southeastern Georgian Bay shoreline, including Collingwood, Barrie, Angus, and Keswick. Additional, weaker bands may impact regions east of Lake Huron, from Owen Sound to Goderich.

By midnight, models suggest that a narrow but intense squall could set up, stretching from the Bruce Peninsula, over Georgian Bay, and into Barrie. However, there’s still uncertainty about its exact strength and how stationary it will be overnight. Some models show it drifting north toward Midland and Orillia, while others keep it in place longer.

If the squall aligns just right, it could connect with both Lake Huron and Georgian Bay, allowing it to tap into additional moisture. This could make it stronger than expected, potentially bringing more snow to Barrie than initially forecasted. Right now, Barrie sits right on the edge between significant snowfall and minimal accumulation.

By Friday morning, the squall will likely continue hammering the Bruce Peninsula and Simcoe County but may have shifted slightly north, putting Tobermory, Midland, and Orillia in the bullseye for heavy snow during the late morning.

Depending on its strength, the squall could even extend into portions of Durham and the Kawartha Lakes at times. This squall may remain stationary for several hours, with snowfall rates reaching 5-10 cm per hour.

It won’t take long for roads to become impassable, especially along the Highway 400 and Highway 11 corridors. Plows will struggle to keep up with such intense snowfall rates, and whiteout conditions will make travel extremely dangerous. If you can, stay home—this is the kind of snow that can lead to major travel disruptions and accidents.

By early Friday afternoon, the squall should gradually weaken as winds shift and become less favourable for lake effect snow.

As with any lake effect event, snowfall totals will be highly variable, depending on where these narrow snow bands set up.

The hardest-hit areas are expected to be across the Bruce Peninsula, including Tobermory, Lion’s Head, and Wiarton, extending into Simcoe County in areas like Midland, Washago, and Orillia. These regions could see 15 to 25 cm, with localized totals near 40 cm possible in central Simcoe County, closer to Georgian Bay.

Surrounding areas—including Grey-Bruce, Huron, and Perth counties east of Lake Huron—could see 5 to 15 cm, though some spots may see little to no snow due to how localized these bands are. Southern Muskoka, portions of Kawartha Lakes, and Durham Region may also receive up to 5 to 10 cm in some areas.

The rest of Southern Ontario should see less than 5 cm of snow over the next 24 hours, as the lake effect snow stays confined to the snowbelt regions.

While the lake effect snow wraps up Friday, a much bigger storm could be on the way this weekend. A potential multi-day snowfall event is on track to begin Saturday, and continue into Sunday.

Right now, there’s still uncertainty regarding snowfall totals and the exact timing of the worst conditions, but early indications suggest that much of Southern Ontario—particularly Eastern Ontario and the Golden Horseshoe—could see 20-30 cm or more by the end of the weekend.

We’re waiting on the latest model data this evening and will have a preliminary forecast on this potential snowstorm later today or early Friday. Stay tuned!

February 06, 2025

Snow Squalls to End Off the Week in Parts of Southern Ontario With Up to 25cm of Snow Possible by Friday

February 06, 2025/ Brennen Perry

While we’ve had a break from snow squall activity over the past week, they are expected to return as we close out the week, bringing another round of lake-effect snow to areas around Lake Huron and Georgian Bay.

As the system that brought a messy mix of wintry weather moves out, colder air will briefly settle into Southern Ontario. This drop in temperature, combined with strong westerly to northwesterly winds blowing over the still mostly ice-free lakes, will create the perfect conditions for snow squall development.

Overnight Thursday, shifting winds will likely trigger several narrow bands of heavy snow that will sweep across Southern Ontario before becoming more organized over Lake Huron and Georgian Bay.

While these bands won’t last long—most areas will only see snow for 15 to 30 minutes—they could still create hazardous driving conditions. Strong wind gusts of 70-80 km/h will cause blowing snow, significantly reducing visibility on the roads.

However, for regions within the snowbelt, which have already been hit hard by squalls in recent weeks, this could be another significant snowfall event. Parts of Grey-Bruce and Simcoe County may see totals reaching 15 to 25 cm in the hardest-hit communities by the end of Friday.

More organized squalls are likely to develop early Friday morning, targeting the Bruce Peninsula and extending into Simcoe County. This narrow but intense band will likely persist throughout much of the day, though it may shift somewhat as winds fluctuate.

Current model data indicates that the heaviest snow will remain focused within the Wiarton-to-Owen Sound corridor in Grey-Bruce and between Orillia and Barrie in Simcoe County. At times, the squall could extend further inland, bringing periods of heavy snow to parts of Kawartha Lakes, Durham, and Peterborough during the morning and afternoon.

By Friday evening, a shift in wind direction will bring a few hours of intense snowfall to parts of Southern Muskoka, including MacTier, Port Carling, Bala, Gravenhurst, and Bracebridge. However, this squall is expected to weaken quickly after midnight as winds subside.

With the snow band moving around throughout the day, widespread extreme accumulations are less likely, but it will allow more regions to see bursts of heavy snowfall at different times.

We’re expecting total snowfall accumulations of 15 to 25 cm across the central Bruce Peninsula, including Wiarton and Lion’s Head, extending into most of Simcoe County.

The City of Barrie is expected to avoid the worst of the snowfall, but if the squall sinks slightly farther south for a few hours, the city could still see around 10-15 cm of accumulation.

For the rest of Grey-Bruce, including Owen Sound, Hanover, and Collingwood, as well as Muskoka, Kawartha Lakes, and Peterborough, snowfall totals will generally range between 5 to 10 cm, though some localized pockets may receive up to 15 cm.

Outside of the snowbelt, snowfall will be minimal, with 2-5 cm expected across the rest of Central Ontario and less than 2 cm for Eastern Ontario and the Golden Horseshoe.

Deep Southwestern Ontario will likely remain snow-free from this round of lake-effect snow.

**PRECIPITATION TYPE** - MAP FROM WEATHERBELL

After the snow squalls, attention will turn to Saturday night, which, at one point, looked like it could bring Southern Ontario its strongest winter storm of the season. However, recent model data now suggests that much of the system’s moisture may stay south of the border, shifting into the U.S. Northeast instead.

If this trend continues, instead of widespread snowfall totals of 10-20 cm, most of Southern Ontario could see just 5 to 10 cm—and even that might be on the high end.

For those hoping for a big winter storm, it looks like luck isn’t on your side this time. That said, we’re still in an active storm track, and the next few weeks will bring more chances for Southern Ontario to get hit with a classic winter storm.

January 28, 2025

Another Dumping of Snow as an Alberta Clipper Targets Southern Ontario With Up to 20cm of Snow by Wednesday

January 28, 2025/ Brennen Perry

As January 2025 draws to a close, Southern Ontario’s weather has varied greatly depending on the region.

Snowbelt areas near Lake Huron and Georgian Bay have been bombarded by persistent lake-effect snow over the past couple of weeks. Meanwhile, Eastern and Deep Southwestern Ontario have seen little snow this month, as no significant systems have impacted those areas.

That pattern is about to shift, with an Alberta Clipper poised to bring a widespread snowfall event across Southern Ontario. This system is expected to deliver 10 to 20 cm of snow to Eastern, Central, and Southwestern Ontario over the next 24 hours, including the snowbelt regions.

In addition to the clipper, snow squalls are forecast to develop Wednesday afternoon and continue into the evening. Combined system snow and lake effect snow could bring an additional 20 to 30 cm to areas east of Lake Huron between Tuesday and Wednesday.

Snowfall from the clipper has already begun moving into Southwestern Ontario near Lake Huron as of late Tuesday afternoon.

Moderate to heavy snow will spread eastward through the evening, with the heaviest snow expected in the Greater Toronto Area (GTA) and Central Ontario during the late afternoon and early evening.

Localized heavier snow is likely along the Lake Huron and Georgian Bay shorelines, particularly over the Bruce Peninsula, where lake enhancement will add extra moisture to the system.

For Southwestern Ontario, snowfall will begin to taper off by the evening and should exit areas southwest of Lake Simcoe by midnight.

Central and Eastern Ontario will continue to see snow through the early overnight hours, with the Ottawa Valley potentially experiencing snowfall until Wednesday morning, tapering off around sunrise.

Following the system’s departure, lake effect snow is expected to ramp up over Lake Huron and Georgian Bay.

Models indicate disorganized snow bands developing off Lake Huron on Wednesday afternoon, impacting areas like Grey, Bruce, Huron, and Perth counties. These bands may occasionally extend as far as Kitchener and Hamilton.

Additionally, a snow squall may form southeast of Georgian Bay, bringing heavy snow to the Barrie and Innisfil areas Wednesday afternoon. The intensity and duration of this squall remain uncertain.

By Wednesday evening, activity over Lake Huron may consolidate into a stronger squall targeting the corridor between Southampton and Kincardine, potentially extending to the Hanover area. This squall could lead to rapid snowfall accumulation before gradually weakening after midnight.

The highest snowfall totals over the next 24 hours are expected in the Grey-Bruce region.

Communities such as Port Elgin, Kincardine, Owen Sound, Chatsworth, Mildmay, and Hanover are forecast to receive 10 to 15 cm of snow from the clipper and an additional 10 to 20 cm from lake effect snow on Wednesday.

This could bring total accumulations to 20 to 30 cm, with isolated pockets potentially exceeding 30 cm.

Across Central and Eastern Ontario, Alberta Clipper snowfall is generally expected to range from 10 to 15 cm. Areas southeast of Georgian Bay, including Barrie, may see near 20 cm due to the added snow from Wednesday afternoon’s localized squalls.

Lower totals are expected in the GTA and Niagara regions, as the system’s moisture will primarily focus further north, and lake enhancement will not play a role.

Snowfall amounts in the GTA are expected to range from 4 to 8 cm, with Hamilton and the Niagara corridor seeing even less at 2 to 4 cm.

Deep Southwestern Ontario, including Windsor, Chatham, Sarnia, and London, will see little to no snow from this system. London could receive a few centimetres, while Windsor may only see a trace.

Looking ahead, we are monitoring a potential system moving in on Friday, which could bring snow and freezing rain to parts of Southern Ontario. Stay tuned for updates.

January 25, 2025

Snow Squalls Return to Southern Ontario This Weekend With Up to 20cm of Snow; Potential Wind Storm on Monday

January 25, 2025/ Brennen Perry

Southern Ontario has been gradually climbing out of the deep freeze earlier this week, which brought wind chills plunging into the -30s. This temporary reprieve has also slowed down the lake-effect snow machine.

However, a fresh surge of cold air over the next 24 hours will reignite the potential for snow squalls, particularly around Georgian Bay.

The good news is that this round of snow squall activity should be relatively short-lived. The squalls are expected to drift rather than anchor in one spot, which will help limit overall snowfall accumulation.

By the end of Sunday, areas along the eastern Georgian Bay shoreline and the Bruce Peninsula are forecast to receive between 10 and 20 cm of snow.

Despite the shorter duration, these squalls could still create hazardous conditions. Wind gusts will likely lead to blowing snow, further reducing visibility on roads and making travel potentially dangerous.

Looking ahead, once the snow squalls subside late Sunday, attention shifts to a potentially significant windstorm developing across Southern Ontario starting Monday morning and lasting through the day.

Based on the latest data, wind gusts could approach or even exceed 100 km/h in some regions.

This powerful wind event will coincide with the arrival of a weather system bringing widespread snowfall to Southern Ontario beginning Monday afternoon.

While snowfall totals from the system are expected to range between 5 and 15 cm, the combination of strong wind gusts and falling snow could lead to blowing snow and, in some areas, blizzard conditions.

Driving conditions during Monday’s evening commute are expected to be very poor, with a high risk of power outages in areas that experience the strongest wind gusts.

Be prepared for possible heating disruptions if outages occur, as temperatures are forecast to drop sharply Monday night.

The cold front responsible for these changing conditions will sweep through Southern Ontario on Saturday evening. While surface temperatures will remain relatively stable, colder air aloft will fuel the lake-effect snow machine.

As a result, heavier snow pockets may develop east of Georgian Bay, particularly in the Parry Sound and northern Muskoka regions, aided by lake enhancement.

Snow squalls could also form within this setup, bringing locally higher snowfall amounts. Current projections suggest 5 to 15 cm of accumulation by Wednesday morning, but totals could reach up to 20 or even 25 cm if conditions align perfectly.

High-resolution models show a significant snow squall developing over the southern Bruce Peninsula on Sunday morning.

This squall may extend across Georgian Bay, reaching Simcoe County and parts of Kawartha Lakes. It appears likely to linger for several hours between Orillia and Barrie, producing intense snowfall with rates approaching 5 cm per hour.

As the squall moves into Simcoe County during the afternoon, it is expected to weaken, leading to reduced snowfall rates. Additionally, weaker bands of lake-effect snow could develop off Lake Huron, potentially affecting areas like Kincardine, Hanover, and even parts of the Greater Toronto Area.

However, these bands are less certain and may only persist for a few hours on Sunday morning.

By Sunday evening, snow squall activity will likely shift northward into Muskoka and Parry Sound, intensifying briefly and delivering heavy snow to areas like Port Carling and Bracebridge.

Organized lake-effect snow activity should taper off by midnight, although minor flurries may linger into early Monday morning.

Because the squalls are expected to move frequently, snowfall will be spread across a wider area rather than concentrating in one location.

Most regions along the eastern Georgian Bay shoreline, including Barrie, Muskoka, and Parry Sound, are forecast to receive between 10 and 20 cm of snow by Sunday evening. This also applies to the Bruce Peninsula and areas like Owen Sound and Meaford.

Localized amounts exceeding 20 cm are possible, particularly in the corridor between Orillia and Barrie, where intense snow squalls are expected on Sunday morning. However, the current data does not support widespread totals in the 20-30 cm range.

Outside the primary snowbelt areas, regions such as Haliburton, Lindsay, Keswick, and Flesherton are likely to see 5 to 10 cm of snow, depending on the placement of snow squalls and how far inland they extend.

For the rest of Southern Ontario, snowfall amounts will generally be less than 5 cm, with most of the snow falling on Saturday evening and overnight.

The windstorm on Monday is expected to bring the strongest gusts to higher elevations, including the Dundalk Highlands, Collingwood, and Orangeville.

Wind gusts in these areas could reach 100 to 110 km/h, with similar strength expected along the escarpment, down into Hamilton, and across the Niagara region along the Lake Erie shoreline.

In Southwestern Ontario, gusts could exceed 90 km/h in areas east of Lake Huron, extending into Kitchener and the western Greater Toronto Area.

Elsewhere across Southern Ontario, gusts will likely range from 80 to 90 km/h, while Central and Eastern Ontario could see slightly weaker gusts of 70 to 80 km/h.

The addition of widespread snowfall on Monday afternoon and evening will exacerbate the impact of the wind. Blowing snow could create whiteout conditions, and some areas may experience blizzard-like conditions, especially in Southwestern Ontario.

While snowfall totals from this system aren’t expected to be excessive, with 5 to 15 cm possible across Southwestern and Central Ontario, the combination of snow and strong winds will make travel extremely challenging.

Further details on timing and accumulation specifics will be shared in a forecast update on Sunday. Stay tuned!

January 19, 2025

High-Impact Snow Squall Event Could Bring Up to 100 cm and Blizzard Conditions to Southern Ontario’s Snowbelt Starting Monday

January 19, 2025/ Brennen Perry

*MAP UPDATED @ 3:30 PM - JANUARY 20, 2025 -* ***NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE***

Chilly Arctic air has begun sweeping into Southern Ontario this weekend, marking the return of lake-effect snow activity off the Great Lakes. While snow squalls on Sunday have been relatively limited, they are expected to organize and intensify as the evening progresses.

Intense snow squalls are set to impact areas around Lake Huron and Georgian Bay from Monday through Tuesday. Portions of the Niagara region and Prince Edward County may also experience squalls driven by activity off Lake Ontario and Lake Erie.

Moderate wind gusts of 50-60 km/h are likely to develop on Monday morning. When combined with heavy snow, these winds could cause blowing snow and localized blizzard-like conditions in some areas. Poor travel conditions are anticipated, with road closures possible throughout Monday and into Tuesday.

The Bruce Peninsula is expected to bear the brunt of these squalls. A prolonged and intense squall is likely to lock in over the region from Monday afternoon through Tuesday, with snowfall totals potentially approaching 100 cm.

Other areas along the Lake Huron shoreline, as well as parts of Simcoe County and Muskoka, could see snowfall accumulations of 25-50 cm by the end of Tuesday.

This forecast also extends to the southern tip of Prince Edward County, south of Picton, where a Lake Ontario squall could drift across the county before moving into New York State.

As of Sunday evening, a pocket of heavy snow over Lake Ontario is affecting northern Niagara. Meanwhile, a squall over Lake Huron has diminished but is expected to reorganize by midnight.

According to the latest model data, a very narrow yet intense squall is likely to develop over the Goderich area overnight. Snowfall rates could reach 10-15 cm per hour, with higher ratios due to colder temperatures.

This could result in rapid snow accumulation across Huron County, particularly in the Goderich region, through Monday morning.

There is some uncertainty regarding how far inland this squall will extend. However, it could potentially stretch into the Kitchener area, through Burlington and Hamilton, and become further enhanced as it moves back onshore over the Niagara region via Lake Ontario.

By Monday afternoon, a shift to more westerly winds is expected, pushing the Lake Huron squall towards the Bruce Peninsula. The squall is predicted to stall over the northern and central parts of the peninsula by Monday evening.

Wind gusts will strengthen throughout Monday afternoon and evening, reaching 50-60 km/h in some areas. These winds are likely to create blowing snow and near-zero visibility, making travel nearly impossible east of Lake Huron. While conditions may not officially meet blizzard criteria, they will be very close.

Model projections diverge on the squall's movement after it crosses Georgian Bay. Canadian models suggest a variable wind direction could cause the squall to curve northward into Muskoka and Parry Sound instead of continuing east.

Meanwhile, the American model indicates a more southerly trajectory, targeting Midland, Honey Harbour, and Washago. This model also suggests secondary squall activity could impact southern Bruce-Grey areas, including Port Elgin and Owen Sound.

Both models agree that upper-level winds will likely keep the squall close to the Georgian Bay shoreline. This may spare inland areas like Bracebridge, Gravenhurst, and Orillia from the heaviest snowfall, though the squall's reach could still surprise some locations.

There is also uncertainty regarding squalls over Lake Ontario and Lake Erie. While these squalls may drift northward into Fort Erie and southern Prince Edward County, they could remain concentrated south of the border.

Snow squall activity is expected to remain stationary through Monday night into Tuesday morning, with snowfall rates of 5-10 cm per hour possible.

The Bruce Peninsula squall may gradually drift southward on Tuesday afternoon, although it is expected to weaken slightly as wind directions shift. Despite this, squalls will likely persist over the Grey-Bruce region throughout Tuesday.

Snow squalls are anticipated to continue into Wednesday, although their intensity and direction remain uncertain. Southwesterly winds may develop, which could direct squalls over the Bruce Peninsula and extend into the Parry Sound region.

UPDATED FORECAST (3:30 PM - JAN 20, 2025)

Muskoka, before you grab a pitchfork to take out your snow frustrations, you might want to trade it in for a snow shovel—you’re going to need it. 😉

The latest model data this morning doesn’t bring good news for those in Muskoka hoping for a break from the snow. How does another 50-100 cm sound?

In our initial forecast, we mentioned that model data suggested snow squall activity would stay primarily along the Georgian Bay shoreline. This meant that areas further inland, such as Bracebridge, Port Carling, and Gravenhurst, could avoid the brunt of the snow.

Unfortunately, the newest data paints a different picture. This morning’s updates indicate that snow squalls will push much further inland than originally expected. The models also show an increase in the intensity of these squalls, starting late this afternoon and continuing all day through Tuesday.

As a result, we’ve made adjustments to our forecast, extending the zone of heavy snow further inland east of Georgian Bay. Additionally, we’re now introducing a 50-100 cm snowfall zone for Muskoka, similar to what was previously focused over the Bruce Peninsula.

Locations such as Port Carling, Rosseau, Port Sydney, and Bracebridge are now directly in the crosshairs, with the potential for up to 100 cm of snow by the end of Tuesday. Meanwhile, the forecast for the Bruce Peninsula—covering Tobermory, Lion’s Head, and Wiarton—remains unchanged, with totals still expected to reach 50-100 cm.

For the rest of Muskoka, including Huntsville and Gravenhurst, as well as Parry Sound and Midland, snowfall accumulations of 25-50 cm are likely. This range also applies to the Owen Sound, Meaford, and Port Elgin areas.

You might notice a slight reduction in the forecast east of Lake Huron. This adjustment reflects snowfall that already occurred last night and early this morning, especially in areas like Goderich. These regions are expected to see an additional 15-25 cm of snow by the end of Tuesday.

Our forecast for Fort Erie and Prince Edward County remains unchanged. Squall activity off Lake Erie and Lake Ontario could bring 15-25 cm of snow to the southern Niagara region, including Fort Erie. Meanwhile, southern Prince Edward County, particularly south of Picton, could see totals ranging from 25-50 cm.

See below for our Lake Ontario and Lake Erie forecast.

PREVIOUS FORECAST:

Given the frequent mention of the Bruce Peninsula in this forecast, it’s no surprise that this region is expected to receive the most snowfall from this event.

Accumulations of 50-100 cm are projected for areas including Tobermory, Lion’s Head, and Wiarton. Some locations may even exceed 100 cm if the squall remains stationary for an extended period.

Along the Lake Huron shoreline, areas such as Goderich, Point Clark, Kincardine, Port Elgin, Chatsworth, Owen Sound, and Meaford are likely to see 25-50 cm of snowfall by Tuesday’s end. As with most snow squalls, localized variations in totals are expected based on the squall's exact path.

Similar snowfall amounts of 25-50 cm are possible along the eastern Georgian Bay shoreline, including Midland and MacTier. However, these totals will be highly localized, as the squall’s path is still uncertain.

Further inland, areas east of Lake Huron, such as Listowel, Hanover, and Flesherton, are forecasted to receive 15-25 cm of snow. Western Muskoka and Simcoe County, including Port Carling, Bala, Washago, and Gravenhurst, could also see 15-25 cm.

Brief periods of heavy snow are possible in the western GTA, Kitchener, Barrie, and parts of Muskoka, leading to localized accumulations of 5-15 cm. Most areas will likely remain on the lower end of this range, but isolated pockets could approach 15 cm.

The St. Catharines and Niagara-on-the-Lake regions are currently experiencing locally heavy snow, which is expected to continue overnight. By Monday morning, total snowfall, including amounts already fallen, could range from 15-25 cm.

Fort Erie may also see 15-25 cm of snow if the Lake Erie squall edges far enough north. However, there is a possibility that the squall will remain south of the border, resulting in minimal accumulation on the Canadian side.

In Prince Edward County, the southernmost tip exposed to Lake Ontario could see 25-50 cm of snow. Slight shifts in the squall’s position could significantly impact snowfall totals, with Picton potentially receiving 15-25 cm under favourable conditions.

The rest of Southern Ontario is expected to see less than 5 cm of snow from this event. The Ottawa Valley and areas in deep southwestern Ontario will likely experience the least snowfall, with accumulations of less than 2 cm by Tuesday.

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