June 27, 2025

Southern Ontario Faces Widespread Severe Threat Including Damaging Wind Gusts, Toonie-Sized Hail & Tornado Risk on Friday

June 27, 2025/ Brennen Perry

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

After Southern Ontario experienced some severe weather last weekend along with our first significant heat wave of the season, things have quieted down over the past few days. Milder air brought temperatures back to seasonal values on Wednesday and Thursday.

However, it looks like we’re about to heat up again heading into the weekend. The good news is, it won’t be anywhere near the oppressive heat we saw earlier this week.

In addition to the return of summer warmth, there’s a growing risk of widespread severe storms on Friday. This threat covers much of Southwestern Ontario and stretches into parts of Central Ontario and the Golden Horseshoe.

Isolated thunderstorms are expected to fire up over Lake Huron and move into a very unstable environment during the afternoon, leading to the possibility of all severe weather hazards. This includes damaging wind gusts, large hail and potentially even one or two tornadoes.

As these storms push eastward into the evening hours, there’s a chance they could merge into one larger cluster of storms. This line may reach portions of the Greater Toronto Area and bring a continued threat of damaging winds, small hail and localized flash flooding.

**ESTIMATED DAYTIME HIGH in °C** - MAP FROM WEATHERBELL

While the heat has pulled back across much of Southern Ontario over the past few days (except for Deep Southwestern Ontario), we’re expecting it to return on Friday. Areas south of Lake Simcoe will likely see daytime highs climb back into the upper 20s and even low to mid-30s across parts of Southwestern Ontario.

This won’t be the same level of heat we saw earlier in the week, but it will be a noticeable jump compared to the cooler air on Thursday that kept many places under 20°C for most of the day.

Once you factor in the humidity, some parts of Deep Southwestern Ontario could be feeling close to the upper 30s again.

**SIMULATED RADAR** - MAP FROM WEATHERBELL

As we often see on days with elevated storm risk, the morning could bring some scattered showers or thunderstorms near Lake Huron and Georgian Bay. These are not expected to be severe, but they will play an important role in shaping the setup for later in the day.

If the morning rain and storms linger longer than expected, they could limit afternoon storm development by preventing the atmosphere from fully recovering. This could reduce the strength or delay the timing of any severe storms into the evening when conditions aren’t quite as favourable.

There’s also some disagreement in the forecast models about how far south this morning precipitation might extend, especially in the zone where the severe risk is currently expected to be the highest.

If the atmosphere is able to recover in time, we could see isolated storms begin to fire over Lake Huron as early as mid-afternoon (2 to 4 PM), then track inland toward Grey, Bruce and Huron counties.

There’s still some uncertainty on the exact placement of this development. Storms could form anywhere along a corridor stretching from Manitoulin Island all the way down to Sarnia.

**ESTIMATED ENVIRONMENT FOR TORNADOES** - MAP FROM WEATHERBELL

As these cells develop over Lake Huron, they’ll be moving into a rapidly strengthening environment. Current model data suggests the highest tornado potential may be from Goderich to Owen Sound around 3-5 PM.

This region could see the greatest risk for severe weather during the mid to late afternoon hours. Storms that remain isolated early on may evolve into supercells capable of producing damaging wind gusts, large hail and a tornado or two.

While this particular setup leans more toward Southwestern Ontario, other models point to a similarly strong environment farther northeast into Central Ontario. This includes areas around Lake Simcoe, as well as parts of Simcoe County, Muskoka and the Kawartha Lakes.

As the storms push eastward during the late afternoon, current data suggests they may merge into one larger cluster of storms by the time they reach Central Ontario and then move into the Greater Toronto Area during the early evening.

At that point, the tornado threat will decrease, but the risk of damaging winds will become the dominant threat. This is typical when storms evolve into more linear systems.

Flash flooding could also become a major concern, especially in urban areas like the GTA, which are more prone to poor drainage. Some forecast models even suggest that this line could stall or ‘train’ over the same area, which would bring the potential for very heavy rainfall in a short amount of time.

The overall severe threat should begin to wind down between 9 and 10 PM as the sun sets and daytime heating fades. That said, the storm cluster may continue eastward into the Niagara Region and parts of Eastern Ontario overnight, though it’s expected to be non-severe by then.

As mentioned, the highest severe threat will likely be in the mid to late afternoon over Southwestern Ontario, especially as storms come ashore from Lake Huron.

These storms could bring damaging wind gusts, hail up to the size of toonies and possibly one or two tornadoes. The tornado risk would be greatest shortly after the storms reach land and should taper off farther inland.

Deep Southwestern Ontario might also see a few isolated storms develop during the afternoon, though the environment doesn’t look quite as favourable compared to areas farther north.

Still, any storms that do form here could bring isolated damaging wind gusts, quarter-sized hail and even a low-end tornado risk that can’t be ruled out.

As the storms move into Central Ontario later in the day, the primary risk will transition to damaging winds. The threat of hail and tornadoes will decrease, but a few storms could still produce quarter-sized hail and, again, an isolated tornado remains possible.

There’s also the potential for some isolated development around Georgian Bay and Lake Simcoe in the afternoon. If that happens, it could boost the tornado and hail risk across that region.

By the time the line of storms reaches the Golden Horseshoe, it will likely be starting to weaken. However, it could still bring the potential for isolated wind damage, nickel-sized hail and maybe a brief tornado, though that risk becomes increasingly unlikely at that point.

June 21, 2025

Southern Ontario to Kick Off Summer This Weekend With Significant Severe Risk and Tornado Threat on Saturday; Sizzling Heat Near 40°C on Sunday

June 21, 2025/ Brennen Perry

Summer officially arrived late Friday night with the summer solstice, and it looks like Mother Nature isn’t wasting any time making it feel like summer across Southern Ontario. A multi-day heat wave is on the way, bringing the potential for record-breaking temperatures starting Sunday and continuing into early next week.

But before the heat sets in, we’re looking at what could easily be our strongest and most widespread severe weather threat of the season so far on Saturday. There are a lot of factors at play that make this a classic ‘boom or bust’ setup, which we’ll break down below.

There’s high confidence in a potent storm environment stretching across much of Southern Ontario. The big wildcard, however, is whether storms will actually develop to take advantage of all that energy. If they do, they could bring very large hail, destructive wind gusts, and possibly even a couple of tornadoes.

What’s especially concerning is that the storm environment doesn’t fade away after sunset like it typically does. In fact, it remains quite strong through the overnight and into Sunday morning, which could support a nocturnal line of storms with widespread damaging wind potential.

Once the severe risk passes, intense heat begins to build. Temperatures will soar well into the 30s by Sunday, with humidex values making it feel closer to the 40s. The heat continues Monday and Tuesday, with some relief expected midweek. That said, it’ll likely stay warm into the end of June and possibly early July.

A key ingredient in Saturday’s severe weather threat is already unfolding over North Dakota early Saturday morning. An intense line of storms, known as a “derecho” (a fast-moving complex of severe thunderstorms that can produce widespread wind damage), is sweeping through the northern Plains.

This system is producing destructive wind gusts of over 150 km/h along with several tornadoes and has already left damage in its wake. It’s expected to continue tracking eastward into the Great Lakes region through the day.

So what does that mean for Southern Ontario?

Derechos are known to travel long distances, and current model guidance suggests this one could follow a path toward Northeastern Ontario. Areas near the U.S. border, including Sault Ste. Marie and Elliot Lake, could be affected by the remnants of this system Sunday morning.

There’s still some uncertainty around how strong the system will be by the time it reaches Ontario. Forecast models often struggle with capturing the evolution and intensity of derechos, so the possibility that this one is being underestimated shouldn’t be ignored.

The projected track of what’s left of this potentially decaying derecho places it crossing Lake Huron and Georgian Bay into Central Ontario sometime Saturday afternoon.

If it maintains strength, it could bring damaging wind gusts, hail up to the size of toonies and maybe even an isolated tornado. But this could just be the first of multiple storm rounds.

Some models are also hinting at additional isolated storm development around Elliot Lake and Sudbury in the wake of the earlier line. That suggests the atmosphere could quickly recharge, although it’s still unclear how widespread any new storms would be.

As we move into the late afternoon and evening hours on Saturday, the storm environment really ramps up. One of the key indicators we look at, the Significant Tornado Parameter, is literally off the charts in some areas, particularly near the Lake Huron shoreline and into Georgian Bay.

Here’s the catch, though: storms need to develop in this environment to take advantage of it. If they do, they could rapidly become severe, with the potential for all hazards. That includes large hail (possibly golf ball-sized or bigger), destructive winds over 100 km/h, and tornadoes.

Looking at what one model is simulating, there’s a notable lack of storms in the highest risk areas around Lake Huron. Instead, storms appear to fire up along a line from Sudbury to Parry Sound through Muskoka, just northeast of the most primed environment. These storms could still be strong and bring similar hazards.

It’s worth noting that models may be underdoing storm development in Southwestern Ontario. That’s something we’ll need to monitor in real time. If nothing happens in Southwestern Ontario, it could end up being a ‘bust’ - which would be good news for those who aren’t fans of severe storms.

Typically, severe weather threats wind down after sunset as daytime heating fades. But in this case, models are suggesting the environment will remain unusually supportive of storm activity well into the overnight hours and early Sunday.

There’s even the potential that a new line of storms forms north of Georgian Bay and sweeps southeast through Southern Ontario overnight. If this happens, it could evolve into another derecho-type system - similar to the one seen Friday night in North Dakota.

Forecasting derechos is notoriously difficult, as models often fail to capture their full strength and endurance. While nothing is certain, this setup definitely has the ingredients to support a nocturnal derecho-type event.

If this scenario plays out, we could see widespread wind damage across Central and Eastern Ontario, possibly extending into parts of Southwestern Ontario and the Golden Horseshoe.

This is a very tricky forecast, and while we've gone with a ‘significant’ (level 4 out of 5) risk, that doesn’t mean everyone will see storms. The risk will come in waves, and some areas may be completely missed.

That said, the potential severity of any storms that do form justifies this level of concern. We’re talking about the possibility of golf ball-sized hail or larger, destructive wind gusts (possibly from a derecho), and a few tornadoes. The tornado risk will largely depend on storm structure—more linear setups will favour damaging wind, while discrete supercells could increase the tornado threat.

The highest severe risk covers areas around Georgian Bay including Sault Ste. Marie, Elliot Lake, Manitoulin Island, Britt, and into Central Ontario such as Muskoka, Simcoe County and Bancroft.

A broader ‘strong’ risk zone includes much of Central and Eastern Ontario, the northern portions of Southwestern Ontario, and the Greater Toronto Area.

Meanwhile, areas like London, Kitchener, Hamilton and the Niagara region fall into the widespread severe risk category.

For once, Deep Southwestern Ontario may dodge the worst of the storms. Windsor, Chatham and Sarnia are currently in the isolated severe risk zone. While a stray storm can’t be ruled out, most of that region looks to stay quiet Saturday.

There may be another round of severe weather on Sunday afternoon and evening, but confidence in the details is still low. Eastern Ontario may be favoured, but we’ll refine that forecast once Saturday plays out.

Sunday marks the beginning of an extended stretch of dangerously hot temperatures. The most intense heat is expected across Deep Southwestern Ontario into the Golden Horseshoe.

Areas like Windsor, Sarnia, London, Hamilton, Kitchener and Toronto could see daytime highs between 35°C and 40°C. With humidity, it will feel like the mid-40s in many spots.

Locations near Lake Ontario, Lake Erie, Lake Huron and Georgian Bay will be 5 to 10 degrees cooler, but it doesn’t take much distance inland to hit the oppressive heat.

Elsewhere in Southern Ontario, expect highs in the low to mid-30s with humidex values near 40°C.

Heat Safety Tips:

Stay hydrated and avoid strenuous outdoor activity during peak heat hours.
Check in on vulnerable individuals, including the elderly, young children and those with health conditions.
Never leave pets or people in parked vehicles.
Use fans or air conditioning when possible and find shade or cooling centres if needed.

There’s a good chance many locations will break temperature records going as far back as the 1800s over the next few days.

According to Environment Canada, record highs in cities like Toronto, Windsor, Ottawa, London and Hamilton are in the mid to upper 30s for Sunday, Monday and Tuesday. Based on the current forecast, some of these records may fall.

Monday brings more of the same, with extreme heat expanding into parts of Central and Eastern Ontario in addition to Southwestern Ontario and the GTA.

Once again, humidex values will push into the 40s, making it feel extremely uncomfortable and even dangerous for some.

Tuesday will still be hot, but may be slightly cooler compared to Monday. Some relief is on the way by Wednesday, although temperatures will likely stay warm overall.

June 18, 2025

Severe Storms Target Southwestern Ontario Wednesday with Tornado and Damaging Wind Risk

June 18, 2025/ Brennen Perry

Storm season has certainly gotten off to a slow start in Southern Ontario, to say the least. Aside from a few scattered events earlier in the spring, it’s been a fairly quiet lead-up to summer across the region.

However, that’s about to change in a big way. As we approach the summer solstice on Friday, which marks the official start of summer, the pattern is shifting. Warmer temperatures and a more active storm pattern are setting the stage for what looks like a much stormier stretch of weather.

Wednesday’s setup will feature an environment that becomes increasingly favourable for storm development through the day. The main focus will be across Southwestern Ontario and into parts of the Golden Horseshoe during the afternoon and evening hours.

While the storms will likely start off isolated and scattered, they are likely to move quite slowly. This raises the potential for localized flooding, especially in areas that see multiple rounds of heavy rainfall from training storms.

A few storms could also produce near-severe wind gusts and small hail, particularly during the late afternoon and early evening. While not every area will be affected, those that are could see some very heavy rainfall over a short period of time.

The greater concern comes later in the day for Deep Southwestern Ontario, where a more potent setup could take shape.

Storms are expected to develop over Michigan during the afternoon and early evening. As these storms intensify, they may track eastward and cross into Ontario during the evening. Areas such as Windsor, Chatham, and Sarnia could be in the path of these stronger cells.

These storms will be moving into a more unstable environment that could support damaging wind gusts, quarter-sized hail, and potentially even an isolated tornado.

While confidence in storm development across the border is high, the extent of the severe threat in Ontario will depend heavily on the exact timing of when those storms cross into the province.

**ESTIMATED AIR TEMPERATURE** - MAP FROM WEATHERBELL

Before the storms arrive, temperatures will be on the rise across much of Southern Ontario. Afternoon highs are expected to reach the mid to upper 20s across Southwestern Ontario and into the Golden Horseshoe by early afternoon.

Central and Eastern Ontario will be a bit cooler, with highs ranging from the low to mid-20s. The Ottawa Valley could end up a touch warmer than the surrounding areas.

This heat and humidity will act as fuel for thunderstorm development, especially around Lake Huron and into areas near Lake Simcoe by the afternoon. Models vary on how widespread storm activity will be, with some showing scattered pop-up storms and others hinting at a more organized cluster.

Either way, any storms that do develop will be slow-moving, and locations underneath these cells could see multiple rounds of rainfall. That’s where the flood threat becomes more concerning, especially in urban areas that are more prone to flash flooding.

For much of the region, flooding will remain the primary concern. However, a few stronger storms could bring near-severe wind gusts and hail up to nickel size.

By the evening, our attention will turn stateside, where strong to severe storms are expected to organize over Michigan.

These storms are forecast to cross into Deep Southwestern Ontario sometime during the evening. The atmospheric setup in that region will support damaging wind gusts, hail up to the size of quarters, and the potential for a tornado.

Again, the timing will be critical. If these storms arrive before sunset, they’ll have access to better instability and surface heating, making them more capable of becoming severe. However, if they hold off until later in the night, the lack of daylight heating could limit their intensity.

Models are currently showing a narrow window between 6 and 9 PM where the tornado potential could materialize, particularly around Windsor, Leamington, and Chatham. This will depend on how quickly storms move eastward from Michigan and whether they interact with the more favourable environment before it begins to weaken.

Once the sun sets, the tornado threat should diminish quickly, though some thunderstorm activity may continue through the night into early Thursday morning.

While a few non-severe thunderstorms may linger overnight, the severe threat will likely taper off before midnight.

As it stands, the highest risk for severe weather on Wednesday will be focused on Deep Southwestern Ontario, including Windsor, Leamington, Chatham, and Sarnia, with the window for impactful storms likely between 3 PM and midnight.

We’ve placed this region under a Level 2 (Widespread) risk due to the potential for damaging wind gusts and one or two tornadoes. Up to quarter-sized hail and locally up ot 50-100mm of rain is also possible.

Elsewhere across Southwestern Ontario and into the Golden Horseshoe, we’ve gone with a Level 1 (Isolated) risk.

This lower tier is mainly for flooding concerns, as slow-moving storms could drop significant rainfall over the same areas during the afternoon and early evening.

Some locations could also see isolated severe wind gusts, nickel-sized hail, and a very low tornado risk (confined mainly to parts of Southwestern Ontario).

June 08, 2025

Southern Ontario Faces Another Round of Wildfire Smoke and Unhealthy Air This Week

June 08, 2025/ Brennen Perry

Southern Ontario continues to deal with lingering wildfire smoke from fires burning across the Prairies and Northern Ontario. While the thickest smoke has cleared out of the region for now, Thursday and Friday brought some of the worst air quality readings we've seen since at least 2023, with several areas reaching unhealthy levels.

As of Sunday evening, there’s still some smoke in the atmosphere - mainly in the upper levels, but we are seeing minor surface-level impacts. This is resulting in reduced air quality in certain parts of the province, although it’s not nearly as bad as it was a few days ago.

Air quality readings are sitting above 100 in parts of Southwestern Ontario, the Golden Horseshoe, and sections of Northern Ontario. That level falls into the “unhealthy for sensitive groups” category, which includes people with asthma, respiratory conditions, young children, and older adults.

If you’re part of a sensitive group, it’s a good idea to limit your time outdoors, keep your windows closed, and consider wearing a well-fitting N95 mask when you have to go outside. These masks can help reduce exposure to the fine particulate matter found in wildfire smoke.

Elsewhere across Southern Ontario, AQI readings are in the 50 to 100 range, which is considered moderate. That’s not a big concern for healthy individuals, but anyone who is sensitive to air pollution may want to avoid heavy outdoor activities like running or biking.

You might also notice a faint smoky smell in the air, but it's not expected to be too strong. Still, it’s a reminder that there’s pollution present, even if the skies don’t look especially hazy.

**UPPER LEVEL SMOKE CONCENTRATION** - MAP FROM WEATHERBELL

The smoke is expected to stick around overnight and into Monday morning, especially in the lower levels of the atmosphere. By Monday afternoon, we should begin to see some clearing closer to the surface, with air quality likely improving through the day.

Unfortunately, that improvement probably won’t last long. The latest forecast models show another plume of upper-level smoke moving into the region by late Monday. While these models currently suggest limited smoke near the surface, we’ve seen before that they often underestimate how much smoke actually mixes down. So we can’t rule out more air quality issues as the week goes on.

Looking ahead, additional wildfire smoke is a strong possibility, especially as fires continue to grow rapidly across Northwestern Ontario. One major concern right now is the fire near Sandy Lake First Nation, which has prompted a full evacuation of the community. That fire is expected to grow further and could become a major source of smoke for Southern Ontario in the days ahead.

Because of its closer proximity compared to fires in Western Canada, smoke from this fire has a better chance of settling closer to the ground by the time it reaches our region. That means more noticeable impacts, even for those outside of sensitive groups.

Some good news: recent rainfall has helped reduce the fire danger in parts of Ontario, Manitoba, and Northern Saskatchewan—regions that have been hit hard by wildfires over the past couple of weeks. This rain may help slow fire growth and support containment efforts, especially in areas where communities are at risk.

However, the same can’t be said for British Columbia, Alberta, and Southern Saskatchewan. These areas are still facing high to extreme fire danger levels, with dry conditions and tough firefighting environments.

Quebec is also showing some concerning signs, with several pockets of high to extreme fire risk. If wildfires do ignite there, it could add yet another smoke source for Southern Ontario in the coming days.

June 04, 2025

Warm Temperatures Briefly Return With Isolated Severe Thunderstorm Risk for Southern Ontario Wednesday

June 04, 2025/ Brennen Perry

While much of late May across Southern Ontario was dominated by unseasonably cool weather, the start of June is shaping up to be a very different story. Over the past few days, temperatures have rebounded to near-seasonal levels across the region, and that’s just a preview of what’s ahead. But enjoy it while you can because a noticeable cool down is expected later this week.

This early June heat has also arrived with a layer of upper-level smoke drifting in from wildfires burning across Western Canada. This smoke has caused a light haze in the sky, giving the air a faint smoky smell, dimming the sun, and slightly suppressing daytime temperatures compared to what we would have seen under clear skies.

The good news is that much of this smoke is expected to clear out across Southern Ontario overnight into early Wednesday morning. While some lingering smoke may remain high up in the atmosphere, it shouldn’t be as thick or widespread as what we’ve seen over the past 36 hours.

With clearer skies, daytime heating will be more effective, giving temperatures a better shot at reaching their full potential. On Wednesday, we’re expecting highs to climb into the upper 20s and possibly even low 30s in some spots.

A cold front sweeping across the province late Wednesday will bring a shift in the pattern, knocking temperatures back below seasonal for the latter half of the week. This front is also expected to trigger a line of thunderstorms, some of which may be marginally severe.

Primary threats include damaging wind gusts up to 90 km/h, pockets of quarter-sized hail, and localized flooding from slow-moving storms. There is also a very low risk of an isolated tornado, but given the weak storm environment, this threat is quite uncertain and likely limited.

Much of Wednesday will start off hot and hazy, especially across Southern Ontario. Temperatures will rapidly climb into the upper 20s by early afternoon ahead of the approaching cold front. In some areas, particularly Deep Southwestern Ontario, the Golden Horseshoe, and the Ottawa Valley, temperatures could push into the low 30s.

That said, locations along the immediate shorelines of the Great Lakes will likely remain a few degrees cooler due to the lake breeze. These areas, including communities along Lake Erie, Lake Ontario, Lake Huron, and Georgian Bay, should see highs closer to the low to mid-20s.

As the cold front begins moving in from the northwest, starting around 2 to 4 PM near the Bruce Peninsula and the North Bay and Parry Sound region, we’ll see an almost instant temperature drop. It could fall by as much as 10 to 15 degrees within a couple of hours. The front will then gradually push southeast through the rest of the afternoon and into the early evening hours.

As the temperatures rise, it’s crucial to keep our beloved pets safe and comfortable. Here are some essential tips to ensure your furry friends stay cool this summer:

🚗 Never Leave in Cars: Even with windows cracked, the temperature inside a car can rise dramatically in just a few minutes. On a 24°C day, the temperature inside a parked car can soar to 38°C in just 10 minutes. In 30 minutes, it can reach 49°C! Leaving your pet in a car can be deadly, so never leave them unattended.

If you see a pet left unattended in a car in Ontario:

Look for the Owner: Note the car's make, model, and license plate number. Go to nearby businesses to see if you can find the owner.
Call for Help: If you cannot find the owner, call your local animal control or police. You can call the OSPCA at 1-833-9-ANIMAL (264625). If you believe the animal is in immediate distress, call 911 immediately.
Stay with the Pet: Remain with the pet until help arrives.

🏡 Shade & Shelter: Make sure your pets have access to shaded areas to avoid direct sunlight. A cool, sheltered spot can make a big difference.

💧 Hydration is Key: Always provide fresh water for your pets. Dehydration can set in quickly, so keep their water bowl filled and in a shaded area.

🐕 Limit Exercise: Avoid walking your pets during the hottest parts of the day. Early morning or late evening walks are best to prevent overheating.

🐾 Paw Protection: Hot pavement can burn your pet's paws. Walk them on grass whenever possible, or use protective booties to shield their feet.

⚠️ Watch for Signs of Overheating: Symptoms include excessive panting, drooling, and lethargy. If you notice these signs, move your pet to a cooler area immediately and provide water.

Although the smoke won’t be nearly as thick as what we experienced Monday and Tuesday, some light to moderate upper-level smoke may still linger on Wednesday. Forecast models suggest the highest concentrations will likely be around the Golden Horseshoe, including the Greater Toronto Area, Hamilton, and the Niagara region.

There may still be a faint smoky smell in the air at times, but surface-level smoke isn’t expected to be heavy enough to significantly impact air quality. What it could do, however, is hold temperatures back by a couple of degrees in some spots since the sunlight won’t be able to fully break through the smoke layer.

By Thursday, most of this smoke should clear out completely. That said, some models are hinting at another round of wildfire smoke pushing into the region by late this week or into the weekend.

Along with cooler temperatures, the advancing cold front will bring the potential for thunderstorms across Southern Ontario. Current data suggests that a line of storms will begin forming early Wednesday afternoon, stretching from North Bay down into parts of Michigan.

As this front continues to track southeastward, conditions will become more favourable for some of these storms to become locally severe. Isolated threats include damaging winds, large hail, and heavy downpours. The highest risk zone appears to be in a corridor running from Deep Southwestern Ontario through Kitchener and Waterloo, into the Lake Simcoe region, and extending northeast into the Algonquin Park area.

The timing for the strongest activity looks to fall between 3 PM and 6 PM, though it could stretch a bit later, especially in areas near the border. Some model runs even show a rogue thunderstorm crossing into the Windsor or Sarnia area from Michigan during the evening hours.

The overall tornado threat remains low due to the weak storm environment and expected messy storm mode, but it is never zero. Sometimes we do see surprise spin-up tornadoes in Ontario, especially where lake breezes collide and enhance low-level rotation.

After sunset, the severe risk should wind down fairly quickly. However, a few non-severe thunderstorms may continue into the late evening and overnight as the front moves across the Golden Horseshoe and into Eastern Ontario.

June 03, 2025

💨 WINDY WEDNESDAY: Environment Canada Forecasting Severe Thunderstorms With 90km/h Wind Gusts, Toonie Sized Hail & 50mm Flooding

June 03, 2025/ Adam Skinner

Environment Canada has released its latest Thunderstorm Outlook forecasting a “moderate” (2 out of 4) risk for severe thunderstorms across much of Southern Ontario on Wednesday, June 4th, 2025. They mention the potential for 90km/h damaging wind gusts, up to toonie size hail (2-3cm) and 50mm of rainfall that could bring isolated flooding. Timing looks to be from the afternoon to the evening for the strongest storms. Additionally, they mention a “minor” risk (1 out of 4) for thunderstorm activity on Thursday. We’ll break it down below.

💨 Windy Wednesday

Wednesday Morning:

The first storms are expected to arrive overnight Tuesday into Wednesday morning. These will mainly affecting portions of northeastern Ontario. This includes areas north of Sault Ste. Marie, stretching around Timmins and Moosonee towards the Quebec border and regions north of Lake Superior. Expect non-severe thunderstorms, with the main concern being isolated lightning strikes. While widespread heavy rain isn't the primary threat here, local rainfall amounts could reach up to 30 mm, with peak hourly rates around 15 mm. Environment Canada indicates a moderate confidence level for these initial storms.

Wednesday Afternoon and Evening:

The afternoon and evening will bring a risk for severe thunderstorms across much of Southern Ontario. This area could experience isolated storms capable of producing a combination of strong winds, large hail, and heavy rain. Impacts could include damage to plants and crops, and loose objects could be tossed around by the gusty winds. There's also a risk of damage to weaker structures, broken tree branches and even downed trees. With the heavy rain, possible flash flooding and water pooling on roads are also concerns. Rainfall in these stronger storms could locally total up to 50mm, with intense peak hourly rates reaching up to 30mm. It's important to note that areas experiencing several rounds of thunderstorms have the strongest chance of seeing isolated flooding.

Interestingly, Environment Canada adds a caveat for these Southern Ontario storms: while some thunderstorms may indeed produce very gusty winds, hail, and torrential downpours, there's a possibility that smoke aloft might hinder their overall strength. This makes Environment Canada’s confidence of how severe these storms will become lower than normal for this type of setup, despite the potential for “moderate” to “high” impacts.

⛈️ Thunder Thursday

Thursday:

The likelihood of thunderstorms continues into Thursday across many parts of northern, far northern, and southern Ontario including areas like Windsor, London, Toronto, Hamilton, etc. Non-severe thunderstorms remain possible. Once again, isolated lightning strikes will be the main concern with local rainfall generally expected to be less than 15 mm. Environment Canada has moderate confidence in these storms developing.

The focus Thursday shifts towards Eastern Ontario, highlighted as 'Area A' on the forecast map above. This area includes Ottawa, Cornwall, Perth, Brockville and areas east of Kingston. Stronger thunderstorms are possible, bringing hazards of strong winds and hail. If these storms strengthen as expected, they could damage plants and crops and toss loose objects. Environment Canada suggests these storms could produce wind gusts from 70-90 km/h and hail up to 2 cm (nickel size). Additionally, local rainfall amounts are expected to be up to 15 mm.

🔎 Staying Safe and Prepared

As we move into summer and a more active weather pattern, it’s critical to stay informed! To keep a close eye on our latest forecasts and get notified of any alerts, download our free app Instant Weather, available on Apple and Android devices.

Remember the golden rule of lightning safety: "When thunder roars, go indoors!" as there is no safe place outside during a thunderstorm. Ahead of the storms, particularly on Wednesday afternoon and evening in Southern Ontario and throughout Thursday in Eastern Ontario, take a moment to secure any loose outdoor items before the storms arrive. Things like patio furniture, trampolines, and garbage cans can become projectiles in strong winds.

If you're planning to be on the roads, be prepared for challenging driving conditions such as sudden downpours, significantly reduced visibility, and the possibility of water pooling on roadways, especially in areas expecting heavier rainfall.

Stay safe everyone and if it’s safe to do so, share your reports with half a million community members on our Facebook group called Ontario Storm Reports!

Disclaimer: These forecasts are issued by Environment Canada and typically published via their Twitter/X accounts. We receive these forecast via a daily email and often publish them to help inform our communities.

June 01, 2025

Two EF1 Tornadoes Confirmed Northeast of Edmonton From Monday, May 26th, 2025

June 01, 2025/ Brennen Perry

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

Two EF1 tornadoes have been confirmed in Alberta from May 26th, 2025 by the Northern Tornadoes Project (NTP). Thankfully, there were no injuries with these two tornadoes. The strongest of the two was on the ground for an impressive 21.2km and had estimated wind speeds of 175km/h. The two tornadoes touched down near Lac la Biche and left behind lengthy, narrow paths of damage, including a partially removed roof from a home and numerous snapped and uprooted trees.

Investigators from the NTP conducted thorough ground and drone surveys on May 28th and noted that Alannah and Patricia from our own Instant Weather team helped get their team deployed quickly. The NTP wrote: “Thanks to Alannah and Patricia at Instant Weather for their initial (late-night) alert to the damage, allowing us to get our team out faster!” We at IW are grateful that we were able to help NTP with their investigation and super thankful that no one was injured in these two tornadoes. The NTP meticulously documented the aftermath and their findings paint a clear picture of the two separate twisters that tore through the region.

The Atmore Twister – A Lengthy Path of Damage

The first tornado, designated the "Atmore" event, began its destructive journey at approximately 7:00 PM MDT (0100 UTC) on May 26th.

Final EF-Scale Rating: EF1

Estimated Max. Wind Speed: 175 km/h

Track Length: A substantial 21.2 km

Max. Path Width: 300 m

Motion: From the Southwest (approx. 220 degrees)

This twister carved a significant path, causing notable damage to homes near Atmore and Rossian (north of Plamondon). Reports detailed structural impacts and the NTP survey confirmed these, along with extensive tree damage. Satellite imagery review also highlighted the visible tree damage along its long, narrow track. Luckily, despite the substantial property damage, no injuries were reported.

The Avenir Tornado – A Shorter, Wider Impact

Just 25 minutes after the Atmore tornado began, a second EF1, named the "Avenir" event, touched down further to the northeast at approximately 7:25 PM MDT (0125 UTC).

Final EF-Scale Rating: EF1
Estimated Max. Wind Speed: 150 km/h
Track Length: 6.43 km
Max. Path Width: A slightly wider 370 m
Motion: From the South-Southwest (approx. 205 degrees)

While shorter in track length, the Avenir tornado left a clear signature, primarily impacting forested areas near the community of Avenir. Satellite imagery initially revealed its narrow path of tree damage, which was later confirmed and documented by the NTP's ground and drone survey. As with the Atmore event, no injuries were reported in connection with this tornado.

Understanding the Findings

The Northern Tornadoes Project plays a crucial role in confirming, classifying and analyzing tornado damage across Canada. Their use of satellite imagery, followed by on-the-ground surveys with drones, allows for precise classification and understanding of these powerful weather phenomena.

These EF1 tornadoes, with wind speeds reaching up to 175 km/h, serve as a reminder of the potential for severe weather in Alberta. While not the most powerful on the Enhanced Fujita (EF) Scale, they are certainly capable of causing significant localized damage, as evidenced by the events near Lac la Biche.

Find out more & get notified

You can view precise tracks of these tornadoes and explore other Canadian tornado and downburst events on the interactive NTP Dashboard.
Always have a plan for severe weather and download our free app Instant Weather to get notified of any alerts from Environment Canada or any custom updates from the IW team regarding rotation, funnel cloud reports, etc.

May 31, 2025

Forty Years Since Black Friday: Looking Back at the Historic Tornado Outbreak and the Barrie F4 From May 31st 1985

May 31, 2025/ Alannah Campbell

*The damaged ‘welcome to Barrie’ sign following the f4 tornado that hit may 31st, 1985, courtesy of the Barrie Banner.*

On this day in 1985, Southern Ontario experienced violent thunderstorms which produced an outbreak of 14 tornadoes, part of a larger outbreak of 44 tornadoes that also impacted Ohio, Pennsylvania, and New York. This stands as the third largest tornado outbreak in Canadian history and one of the tornadoes from that day was the 7th deadliest on record in Canada.

A total of 88 people lost their lives that day; 8 were in Barrie, two were in Grand Valley, two were in Tottenham, and the rest of the fatalities occurred in the US. Hundreds of people were left homeless across Southern Ontario and total damage from the 14 tornadoes is estimated at well over $100 million (in 1985 dollars).

It was all over in six hours and now, May 31st, 1985 is referred to as Black Friday.

*The daily weather map from the morning of may 31st, 1985, Courtesy of* *the National Weather Service*.

Meteorological Background

The day began with a low pressure system settled over Northern Minnesota and Wisconsin and an associated cold front stretching over Lake Superior and Michigan’s Upper Peninsula, then southward through Lake Michigan and into the Midwest. This system drew in warm, moist air from the Gulf and cool, dry air from the north. It was being driven by a strong upper-level jet stream so as the cold front rapidly swept eastward through the Gulf air mass, it triggered explosive development of severe thunderstorms.

The satellite loop below shows how the thunderstorms developed through the afternoon and evening across the region as the cold front swept through.

*The Visible satellite loop from the afternoon of May 31st, 1985 showing the development of thunderstorms, courtesy of* *the National Weather Service*.

Analysis of the upper air charts shows that winds at the 850mb level were 40 knots (74km/h) and at the 300mb level, they were 100 knots (185 km/h). The winds also changed direction with height which meant the atmosphere had plenty of both vertical speed shear and directional shear, which create rotation in thunderstorms and is a crucial ingredient in the formation of tornadoes.

Environment Canada saw this set up and they proactively issued a Severe Weather Watch at 7am, well ahead of the cold front. The storms started to develop over Lake Huron at 1:40pm and quickly intensified into a line of storms by 2:00pm. At 2:25pm, Environment Canada issued its first Severe Weather Warning of the day, which included the reminder that some severe thunderstorms produce tornadoes.

The line of storms continued to develop over the next couple of hours, travelling eastward at up to 70km/h, and the warnings were subsequently expanded. At 3:45pm, severe thunderstorm warnings extended into Simcoe County and then along the west end of Lake Ontario at 4:53pm as the southern end of the line of storms intensified.

The first tornado warning of the day was issued at 5pm, following confirmation of a touchdown near Shelburne, but it was far too late for the communities that were hit the hardest.

*The timing of severe thunderstorm warnings, tornado warnings, and tornado touchdowns from May 31st, 1985, courtesy of Leduc, Jacobson, and Greer.*

*The tracks of thirteen tornadoes from the May 31st, 1985 outbreak with the Grippen Lake Tornado noticeably missing, courtesy of Leduc, Jacobson, and Greer.*

Timeline of Tornado Development

The entire outbreak began in Southern Ontario, with a tornado touching down near Rush Cove in the Bruce Peninsula at approximately 3:00pm. It was rated an F2 and was on the ground for approximately 4km. This tornado is interesting because it was much earlier and well removed from the other tornadoes in this outbreak. The remaining 13 tornadoes can actually be grouped into separate families because there were spawned by the same parent supercells.

As the cold front continued to march eastward through Southern Ontario that afternoon, the thunderstorms and the formation of tornadoes travelled along with it. Following the Rush Cove tornado, there was a lull in tornadic activity until shortly after 4pm. Over the course of the following hour, 7 tornadoes spawned, ranging in intensity from an F1 to two F4 tornadoes.

At 4:10pm, an F2 dropped near Hopeville, northwest of Shelburne and it travelled 17km. Then, at 4:15pm, two separate tornadoes developed: an F3 in Alma, to the northwest Fergus, which was on the ground for 33km, and a devastating F4 which touched down near Arthur. This F4 was on the ground for a staggering 115km, setting the record for the longest tracking tornado ever in Canada, and produced estimated maximum wind gusts in excess of 400km/h. It brought significant damage to both Grand Valley and Tottenham, located 50km to the east. Sadly, two people lost their lives in each of these communities.

*Damage in Grand Valley following the F4 tornado, courtesy of* *the Orangeville Banner*.

Two minutes later, an F2 touched down near Corbetton, to the northwest of Melancthon. This tornado came from the same supercell thunderstorm as the Hopeville tornado, which had formed only seven minutes prior. This tornado was on the ground for 35km, more than double that of its predecessor.

A little over half an hour later, at 4:50pm, an F2 hit the community of Lisle, to the west of Base Borden, which was also spawned from the same supercell as the Hopeville tornado. It was on the ground for 18km and then seven minutes later, the same storm dropped another tornado just east, an F1 near Essa, which was on the ground for only half a kilometre. The final tornado that this storm produced was the most deadly and destructive of the day, the Barrie F4, which will be discussed in more detail below.

When the Grand Valley-Tottenham tornado finally lifted after being on the ground for well over an hour, its parent supercell went on to produce two more tornadoes: an F1 that touched down north of Uxbridge at 5:40pm and was on the ground for 5km, and another F1 that hit Reaboro, southeast of Lindsay, at 6:05pm and was on the ground for 8km.

While the two main supercells to the north continued to produce multiple tornadoes between 4:00pm and 6:00pm, the thunderstorm behind the Alma tornado didn’t produce another until two hours later, when an F2 touched down east of Highway 35 at 6:15pm, which later tore through Ida along its 9km track. Five minutes later, this storm produced an F3 that travelled 14km along the north shore of Rice Lake and then 15 minutes after that, a final F1 touched down that was on the ground for only 1km near Minto, to the north of Trenton.

This marks 13 total tornadoes from this outbreak and this is what the tally stood at for many years. It wasn’t until around 2010, two and a half decades later, when scientists at Environment Canada were compiling a tornado database, that a missing report from the defunct Kingston Weather Office was found. It detailed damage caused by an F1 tornado which touched down around 8:10pm near Grippen Lake, to the northeast of Kingston. It remains unclear as to why this report was never submitted, but the inclusion of this tornado brings the final number of tornadoes in Southern Ontario on Black Friday to fourteen.

One of the few photos known to exist of the rain-wrapped Barrie Tornado, taken by Gary Crawford from HIghway 11 beside the Drive-In Theatre in Guthrie (edge of Oro). Donated to Instant Weather by Mr. Crawford.

The Barrie F4 Tornado

The Barrie tornado was the strongest of the 14 that touched down on Black Friday, with winds estimated at over 400km/h, making it the second F4 tornado of the day.

The tornado was rain-wrapped as it touched down just outside of the city in a reforestation area, where it snapped many trees and permanently bent even more. It was initially 600m wide, carving a significant path as it approached the edge of Barrie.

As it moved northeastward into the city, the tornado levelled an entire block of homes in the Crawford Street and Patterson Road area, then hit an industrial area known as Molson Park. From there, the tornado turned to travel eastward and crossed Highway 400, terrifying many commuters as their vehicles were pelted by intense winds and debris.

After crossing the Highway, the tornado narrowed to roughly 300m wide and it began devastating the Allendale neighbourhood in the south end of Barrie, destroying homes and uprooting mature trees. Once it ploughed through this built up area, the tornado once again began travelling northeastward. It lastly hit a marina on Kempenfelt Bay before moving out over the water, where it finally dissipated. Given that the end of the tornado’s path of destruction concluded over water, the exact length of its track can not be concretely known, but it is estimated that it was on the ground for approximately 15km.

It was all over in a matter of minutes, but the tornado left scars that would take years to heal.

*The initial Draft of the Official survey of the Barrie F4 tornado done by Scott Somerville at Environment Canada, Courtesy of Michael Newark Tornado Digitized Archive by* *the Northern Tornadoes Project*.

Damage & Aftermath

The destruction brought to Barrie was staggering. In a matter of minutes, 155 people were injured, approximately 800 were left homeless, and damage was initially estimated at over $115 million. Sadly, eight residents lost their lives, including four children.

A total of 605 homes were severely damaged and of those, 265 were deemed uninhabitable. In one case, a townhouse complex just east of Highway 400 had its top storey removed and even sections of the main level. Meanwhile, fifteen industrial buildings west of the highway were completely destroyed and many more sustained significant damage. Vehicles were thrown hundreds of metres and 35 sailboats in Kempenfelt Bay completely disappeared.

*Damage in Barrie following the F4 tornado, Courtesy of* *CTV News*.

It took well over a year for the residents of Barrie to rebuild following the F4 tornado and this tornado alone ended up causing $130 million ($334 million in 2025 dollars) in damage. This does not even cover the physical and mental damage experienced by the residents, some of which can never be repaired.

The City of Barrie chose to commemorate this tragic event with two plaques: one for those who lost their lives and one for those who helped the community rebuild.

Sources:

Harries, K. (Ed.). (1985). Ontario tornado: May 31, 1985. C.F. Boone.

Leduc, M., Jacobson, O., and Greer, B. (1986). The “Black Friday” tornado outbreak in Ontario: A forecaster’s view of the events of May 31, 1985. Chinook, 8(1), 13-18.

Witten, D. E. (1985). May 31, 1985: A deadly tornado outbreak. Weatherwise 38(4), 193-198. https://doi.org/10.1080/00431672.1985.9933314

https://www.cbc.ca/archives/the-tornadoes-that-tore-a-deadly-path-of-destruction-in-ontario-in-1985-1.5575434

https://www.ctvnews.ca/barrie/article/marking-37-years-since-devastating-ontario-tornadoes/

https://www.ctvnews.ca/barrie/article/may-31-1985-the-day-the-sky-unleashed-fury-on-central-ontario/

https://www.theweathernetwork.com/en/news/weather/severe/may-31-1985-outbreak-how-a-lost-14th-tornado-was-found

https://www.theweathernetwork.com/en/news/weather/severe/this-day-in-weather-history-may-31-1985-the-barrie-grandvalley-tottenham-tornadoes

https://www.uwo.ca/ntp/faqs/what_are_canadas_worst_tornadoes.html

https://www.weather.gov/cle/event_19850531_85outbreak

https://www.weather.gov/ctp/TornadoOutbreak_May311985

Special thanks to Dr. David Sills at the Northern Tornadoes Project for his help in answering some inquiries when writing this article.

May 21, 2025

On This Day: The Port Huron/Sarnia F4 Tornado of 1953

May 21, 2025/ Guest User

The front page of the times herald from Port Huron, Michigan from Saturday, May 23rd, 1953.

Michigan, USA

Monday, May 18th, 1953 – A squall line from the north brought cold, damp weather to Oakland County, MI, for over three days. Three days later, on Thursday, May 21st, 1953, severe thunderstorms developed, pushing cold air eastward across Michigan, while a warm front from the south advanced, delivering humid temperatures to St. Clair County. The protracted battle between cooler temperatures and warm, moist air from the south reached its climax over Smiths Creek, Michigan at 3:30pm.

By 4:21pm, local radio stations were receiving reports from the Yale area of severe weather conditions, including heavy winds, rain mixed with hail, and darkening skies. As the winds strengthened to 40MPH, a funnel cloud 200 yards wide began to form. At the WTTH Radio Broadcast Centre in Michigan, host Robin Busse issued an urgent warning to residents, notifying them of a tornado touchdown in Smiths Creek, Michigan and advising them to seek shelter immediately in their basements. Before the signal was lost, Robin Busse made a final plea, exclaiming “OH MY… I’VE NEVER SEEN ANYTHING LIKE THIS! PLEASE SEEK SHELTER! HEAD TO YOUR BASEMENTS!” as the wind howled in the background.

The tornado that struck Smiths Creek, Michigan, then entered Port Huron, Michigan, crossing a Lumber Yard on Military Street, and toppling railroad cars along its path before crossing over the St. Clair River. Ralph Polovich, who was a Times Herald Photographer pulled over on Water Street in Port Huron, Michigan to snap a picture of a ‘’White Water Spout’’ as it crossed the river into Sarnia.

Sarnia, Ontario

May 21st, 1953 started off as any other day; a toasty 29 degrees Celsius at 10:24am. By 12:45pm, the temperature rose to 31 degrees Celsius and up to 35 degrees Celsius by 4:25pm. The thunderstorm that led to the tornado dumped golf ball/baseball-sized hail on Sarnia – the hail, which is credited towards saving lives, cleared the streets of motorists and pedestrians as shelter had been found before the tornado struck.

Another radio station (CHOK), located downtown at 148 Front Street North, was broadcasting music and weather updates to the residents of Sarnia. Karl Monk, who served as the stations manager, started his shift at 4pm. ‘’We got some pretty wild weather coming from the West; raining like cats and dogs’’. “Ladies and gentlemen, I just received a note that a tornado has touched down just west of Port Huron. This storm is tracking eastward towards the St. Clair River and has the capabilities to generate a tornado in the Sarnia Lambton Area’’ he announced.

By 5:45pm the tornado hit South of Sarnia Harbor, where it grew in size to 980 yards wide. Moving to the northeast, the tornado hit the downtown area directly, damaging nearly 100 commercial buildings along Front Street and Christina Street.

The Imperial Theatre’s renowned auditorium in Sarnia, suffered a catastrophic collapse. At least 150 homes were damaged, and prior to exiting Sarnia, the tornado veered northeast an began to dissipate as its path narrowed to just 33 yards in width. CHOK maintained continuous coverage throughout the storm, earning recognition for its tireless warnings to Port Huron and Sarnia residents regarding the impending tornado. Much like Robin Busse, Karl Monk was subsequently credited with saving lives through his timely warnings to the public.

the View through the collapsed dome of the Imperial Theatre, Courtesy of the Sarnia Historical Society.

Interesting Facts:

Most residents initially believed that an explosion had occurred at the Imperial Oil Refinery in Sarnia. Unbeknownst to them, this was the sound of the actual tornado on the ground.
The tornado was believed to have been on the ground for almost 2.5 hours.
When the tornado hit, it caused damages exceeding 17 million dollars, left 500 homeless, and made both countries make changes to the way storm warnings were handled.
Many survivors reported severe damage to their homes, while houses across the street remained unscathed.
The acting Mayor of Sarnia read that the Riot Act would be issued at 11pm that night, which forbade people from going downtown to check out the damage to the area. The area was littered with hazards such as debris, mangled power lines, dead birds and animals, etc. It gave permission for the military to take charge, sending in military personnel from the Ipperwash area, and even calling in the RCMP in to help residents clean up. The National Guard was also called into protect abandoned properties in Port Huron.
Just 3 weeks later, on June 8th, an F5 tornado hit Flint, Michigan at about 8:30pm, touching down by a drive-in theatre and killing 116 residents. Coincidentally, on this day, a dinner was being hosted in Michigan honouring Robin Busse from WTTH for his heroic broadcast just 3 weeks earlier.
Mail from Flint was found in the debris in Sarnia days after the tornado struck.

damage on Brock Street, Courtesy of the Sarnia Historical Society.

One of our Moderators at Instant Weather, Miranda, lives in Sarnia. Her mom was 5 years old and living in Sarnia when the tornado hit. When Miranda asked her mom to describe what it was like, this is what she said:

“My mother, my sister, and myself lived on the corner of Maxwell and Indian Road, 926 Maxwell to be exact. Our house was a small bungalow, with no basement and no place to seek shelter. My mom was outside on a ladder at the time, tending to the property, when she heard the radio broadcaster telling Sarnia to ‘’Seek shelter immediately’’. She yelled for my sister and I, who were playing outside, to get inside right away.

I recall the sky transforming into a greenish-yellow hue, sirens blaring, and the wind beginning to pick up. The heat that had been intense all day, suddenly was met by a drastic drop in temperature. Hail started to fall, roughly the size of a tennis ball. I never seen the tornado, but I did hear what sounded like a train coming in the distance. The tornado did some damage to surrounding properties nearby, our house was spared thankfully.

Later that evening, my mom, sister and myself walked downtown to Christina Street and Front Street to see the devastation first-hand. I remember dead birds everywhere, along with the old cars flipped upside down on the roadways. We lost a lot of trees in Sarnia on this day. It was incredibly scary; I can remember it like it was yesterday.”

A look at the back of Taylor’s Furniture Store on Christina Street, Courtesy of the Sarnia Historical Society.

Further Reading:

https://sarnianewstoday.ca/sarnia/news/2023/05/19/deadly-storm-sarnia-marks-70th-anniversary

https://skyrisecities.com/news/2016/07/cityscape-how-1950s-tornado-kickstarted-urban-renewal-imperial-city.21782

https://www.flickr.com/photos/sarniahistoricalsociety/albums/72157666099572743/

https://www.newspapers.com/article/the-times-herald-1953-tornado/63629417/

https://www.thesarniajournal.ca/top-story/from-the-archives-city-hall-operator-called-in-militia-after-downtown-devastated-by-1953-tornado-7973120

May 21, 2025

Ontario’s First Confirmed Tornado of 2025: EF0 Touches Down Near Woodstock Last Week

May 21, 2025/ Brennen Perry

Ontario’s tornado season has officially begun. The first confirmed tornado of 2025 touched down during the early morning hours of May 16th, just south of Lakeside, Ontario, northwest of Woodstock.

The tornado developed along the leading edge of a line of storms that had tracked into the province from Michigan.

While this EF0 tornado near Lakeside was the first confirmed in Ontario this year, it wasn’t the first in Canada.

According to the Northern Tornadoes Project, this brings Canada’s confirmed tornado count for 2025 to five.

The season began with an EF0 tornado in Alberta in early April, followed by an EF1 in Quebec later that month. Just one day before the Lakeside event, two EF0 tornadoes were confirmed in Manitoba on May 15th.

With peak season still ahead, this serves as a timely reminder that severe weather can happen quickly and under conditions that don’t always look extreme on the surface.

Even low-end risks deserve attention, especially when storms arrive at night, when people are less likely to be tuned in.

The Tornado: A Narrow but Confirmed Touchdown Near Lakeside

**Survey map for the Lakeside EF0 tornado** (source: Northern Tornadoes Project)

According to the Northern Tornadoes Project (NTP), the tornado developed just south of the village of Lakeside, approximately 25 km northwest of Woodstock. It touched down around 3:00 AM EDT, shortly after a squall line of thunderstorms entered the region from the west.

**Drone photo of worst damage point featuring multiple snapped conifers** (source: Northern Tornadoes Project)

Damage was limited to trees and a power pole, with no injuries reported. The tornado was assessed as an EF0, with estimated maximum wind speeds of 115 km/h. It travelled a distance of 3.6 km, with a maximum path width of 160 metres, moving generally from the west-southwest (255°).

**Radar data shows possible rotation near lakeside** (source: iw pro)

Radar imagery at the time showed a compact area of low-level rotation, but due to the storm’s embedded structure and the overnight timing, the event went unwitnessed until damage was reported later that day.

The NTP conducted both ground and drone surveys on May 20th to confirm the tornado’s track and intensity.

This information is sourced from the Northern Tornadoes Project’s full report, which can be found here.

**Survey map showing the location of the EF0 downburst (black oval) and collected data** (source: Northern Tornadoes Project)

In addition to the confirmed tornado near Lakeside, the Northern Tornadoes Project also verified a separate EF0 downburst near Chatham from the same storm system.

The downburst occurred around 2:15 AM EDT, roughly 45 minutes before the tornado, and caused significant damage to several barns, farm buildings, power poles, and trees.

While similar wind damage was reported across parts of Southwestern Ontario—from Windsor to Shrewsbury—only the enhanced damage south of Chatham was surveyed.

Wind speeds were estimated to have peaked at 130 km/h, placing the event at the high end of the EF0 scale. No injuries were reported.

Timeline: Forecast Leading Up to the Tornado

Forecast models began flagging the potential for severe storms several days in advance, particularly in Deep Southwestern Ontario, where the environment appeared favourable for severe weather.

Instant Weather and the U.S. Storm Prediction Center both noted the possibility of tornadoes — albeit marginal — due to the timing and nocturnal nature of the storms. This provided over 24 hours of advance notice about the potential for severe weather.

Despite the lower-end risk, one storm managed to spin up a brief EF0 tornado shortly after 3:00 AM on May 16th.

Instant Weather first highlighted the tornado potential on Wednesday afternoon, referencing the Storm Prediction Center’s forecast and the setup in Michigan and Southwestern Ontario:

#ONStorm #ONwx ⚠️ SEVERE STORM RISK - LATE THURSDAY

Heads up! We’re closely watching the potential for strong storms late Thursday evening into the early morning hours of Friday.

Right now, the highest risk appears to be in Deep Southwestern Ontario—including Windsor, Chatham,… pic.twitter.com/SWU0hV7TAx
— Instant Weather Ontario ⛈️ (@IWeatherON) May 14, 2025

The following morning, just under 24 hours before the confirmed tornado, Instant Weather once again flagged the risk.

This time, the post specifically mentioned that a 2% tornado risk extended into Sarnia, Chatham, Grand Bend, and as far northeast as London, placing the affected area firmly within the broader risk zone:

#ONStorm #ONwx 🌪️ Tornado Thursday for Deep Southwestern Ontario?

The Storm Prediction Center (SPC) has just updated their severe weather outlook—and it now includes a more substantial tornado risk extending into the Windsor area.

They’ve upgraded the region around Windsor to a… pic.twitter.com/XglBkvJxBp
— Instant Weather Ontario ⛈️ (@IWeatherON) May 15, 2025

Later Thursday afternoon, a forecast was issued by Instant Weather calling for the potential of isolated tornadoes overnight. The forecast map outlined a marginal risk that included the area near Lakeside, where the tornado would eventually touch down:

#ONStorm #ONwx ⛈️💨 Nocturnal Thunderstorm Threat With Damaging Wind Gusts and Isolated Tornado Risk for Southwestern Ontario Tonight

📅 Thursday, May 15 - Friday, May 16, 2025

⤵️ VIEW THE FULL FORECAST:https://t.co/Pu0YPOAAVu

- Brennen pic.twitter.com/KYtjPY2hxR
— Instant Weather Ontario ⛈️ (@IWeatherON) May 15, 2025

Around 1:47 AM, just over an hour before the tornado touched down, Instant Weather sent out a custom notification for the London area, referencing minor rotation and clearly stating that “an isolated tornado cannot be ruled out”:

At 2:55 AM, Environment Canada issued a Severe Thunderstorm Warning, which included a note that severe thunderstorms can produce tornadoes. This came approximately five minutes before the tornado would touch down near Lakeside

Finally, live coverage was underway on Instant Weather’s YouTube channel during the time the tornado developed around 3:00 AM, as the storm moved through Oxford County.

May 15, 2025

Nocturnal Thunderstorm Threat With Damaging Wind Gusts and Isolated Tornado Risk for Southwestern Ontario Tonight

May 15, 2025/ Brennen Perry

updated map - 10:50 PM (CLICK HERE FOR THE PREVIOUS MAP)
***NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE***

UPDATE (10:50 PM):

We’ve been closely tracking the line of storms developing across Michigan, and it’s now set to move into Deep Southwestern Ontario over the next few hours.

Based on the latest model data, current environmental conditions, and how well the storm is holding together despite the lack of daylight heating, we believe there’s enough evidence to upgrade parts of Deep Southwestern Ontario to a ‘strong’ (3/5) risk—mainly due to the potential for intense wind gusts.

Large hail up to the size of toonies is also possible, and we can’t completely rule out an isolated tornado.

We’ve also extended the ‘slight’ (2/5) risk further inland to include areas like Goderich and London, as new data suggests the line could stay fairly strong as it tracks deeper into Southwestern Ontario during the pre-dawn hours. Again, damaging wind gusts remain the primary threat.

The line is expected to cross the border just after midnight, with the severe threat gradually tapering off but still continuing until around 3–4 AM.

ORIGINAL FORECAST

While storm season has had a quiet start in Southern Ontario, things are beginning to ramp up with a late-night storm risk expected between Thursday evening and early Friday morning. A strong line of storms is forecast to form across Michigan late tonight, initially beginning as discrete supercells over parts of Wisconsin and Illinois.

Based on the latest guidance, these storms are expected to organize into a more linear structure as they track eastward, eventually crossing into Southwestern Ontario sometime just after midnight. While they’ll likely lose some of their strength after dark, especially without daytime heating, the atmosphere may still be supportive enough for them to maintain some intensity as they move into our region.

That said, there’s still a fair amount of uncertainty about just how strong this line will be once it crosses the border, and how quickly it might weaken as it tracks northeast through the early morning hours of Friday.

The biggest concern with this system is the potential for damaging wind gusts. This squall line will stretch from the Upper Peninsula of Michigan all the way down through Ohio as it enters Ontario, which could lead to widespread impacts. Areas from the Bruce Peninsula all the way down to Deep Southwestern Ontario are at risk of strong winds embedded within the line.

The highest risk appears to be in Deep Southwestern Ontario, where the line will first cross into Ontario. Regions like Windsor, Leamington, Chatham, and Sarnia are most likely to experience the strongest part of this line. While damaging wind gusts are the main hazard, we also can’t completely rule out the chance for hail and even a brief tornado, especially if the storms arrive a bit earlier than forecast.

Hail up to the size of quarters is possible, and while the tornado risk is considered low overall, it does exist. The biggest concern here is that this is a nocturnal threat. If a tornado were to develop overnight, it would be harder to spot and could be rain-wrapped, making it even more dangerous. That’s why it’s so important to stay alert and have a way to receive warnings while you sleep.

Storm development will begin with discrete cells over Wisconsin and Illinois, likely forming into a long line around 8–10 PM near Chicago and across Lake Michigan.

The timing of this formation is crucial. If the line develops sooner and sweeps across Michigan quickly, it could result in a more robust severe risk for Deep Southwestern Ontario, where the environment is more favourable before midnight.

No matter the timing, damaging winds remain the most likely outcome with this type of linear storm setup.

As of now, future radar models suggest the storms will cross into Ontario between 1 and 2 AM, hitting areas like Windsor and Sarnia first before stretching further northeast. However, there’s still wiggle room in this timing. It could arrive earlier and stronger, or later and already weakening before reaching our region.

**ESTIMATED TORNADO ENVIRONMENT** - MAP FROM WEATHERBELL

While widespread wind damage is the primary concern tonight, there is some minor tornado potential—especially in Essex County just after midnight. Again, the odds are low, but not zero.

Because of the overnight timing, it's extra important to have notifications enabled on your phone or weather radio. Make sure you have a way to receive alerts while you're asleep in case a warning is issued. Our free app is a great way to instantly get Environment Canada alerts, along with our custom notifications issued for your exact location.

The line of storms is expected to continue northeast through the early morning hours, bringing heavy rain, gusty winds, and frequent lightning to much of Southwestern Ontario and parts of the Greater Toronto Area between 3 and 6 AM.

While the line should gradually weaken during this time, it could still pack a punch in some localized areas. There’s some uncertainty around how long it will be able to hold its strength since the atmospheric environment in Ontario is notably weaker than what the storms had access to in the U.S.

Latest model runs show the system likely fizzles out once it reaches Lake Simcoe, meaning Eastern and Central Ontario probably won’t see much beyond a few scattered morning showers or storms.

Another round of storms is possible Friday afternoon and evening, particularly for Eastern Ontario and parts of Deep Southwestern Ontario. We’ll have more details on that in a separate update.

As it stands, the highest storm risk tonight is in Deep Southwestern Ontario, where we currently have a slight risk (2/5) for severe weather. The main hazard is damaging wind gusts between 12 and 6 AM, though isolated tornadoes and hail up to the size of quarters are also possible.

For the rest of Southwestern Ontario and the Golden Horseshoe, the risk is lower—a marginal (1/5) severe threat—with isolated pockets of wind damage being the most likely outcome. There’s also a very low tornado risk along the Lake Huron shoreline as the line initially pushes into the region. Hail up to the size of nickels could accompany some of these storms.

In addition to the overnight threat, a few isolated pop-up storms are possible during the late afternoon and early evening across parts of Grey-Bruce. While these are not expected to be severe, funnel clouds are possible, including a low-end risk of a landspout tornado. See our custom notification for more on the funnel cloud setup.

Stay weather-aware tonight. Keep your devices charged, notifications turned on, and have a plan in place just in case you need to take shelter quickly. We’ll continue to monitor the latest data and provide updates as the situation evolves, including a possible live stream later tonight.

April 28, 2025

First Strong Severe Thunderstorm Risk of the Season in Southern Ontario on Tuesday With Tornadoes Possible

April 28, 2025/ Brennen Perry

After a gruelling winter filled with relentless snow squalls, powerful winter storms, and a major ice storm to top it all off, we are finally shifting gears into more typical spring and summer-like weather across Southern Ontario. But with the warmer air comes the return of severe thunderstorms, something Southwestern Ontario has already gotten a small taste of over the past few weeks.

We have been closely tracking the potential for our first strong severe weather threat of the season on Tuesday. Model guidance has been consistently highlighting the potential for a very active environment, one capable of supporting tornadoes, large hail, and damaging wind gusts. That risk still looks to be on track, although there remains some disagreement between models on exactly where the strongest environment will set up.

At this time, we believe the strongest severe weather risk will focus across parts of Southwestern Ontario, Central Ontario, and into Eastern Ontario. Other areas across Southern Ontario will still carry a marginal to slight risk, meaning a few severe storms could pop up, but the widespread threat will be lower outside the main zone.

Tuesday’s possible storm threats include one or two tornadoes, large hail — potentially up to the size of toonies or even timbits — widespread damaging wind gusts over 90-100 km/h, and heavy rainfall that could cause localized flooding in some spots.

The storm risk will kick off early Tuesday morning as an area of convection moves across the region between 6:00 a.m. and 12:00 p.m. Most of these morning storms should remain non-severe, but we can't rule out a rogue severe cell, especially in setups like this. Where these morning storms track and how quickly they clear out will be important to watch, as leftover clouds or rain could limit how unstable the atmosphere becomes later in the day.

By the early afternoon hours, the environment is expected to rapidly become more favorable for severe weather. Areas along the Lake Huron shoreline will likely be the first to feel the effects, with the risk then spreading into parts of Central Ontario.

Even though we are confident that the setup is capable of producing severe storms, it’s important to stress that storms actually have to form to take advantage of the environment. Not everyone in the higher-risk zone will necessarily see a storm. These will be isolated events, meaning only a small percentage of the region will be directly impacted.

The highest tornado risk will likely occur earlier in the day across Southwestern and Central Ontario, when individual storms (known as discrete supercells) can remain separated and feed off the prime environment around them.

As the afternoon progresses and storms track further eastward, we expect that they will start to merge into more of a line, which would shift the threat more towards damaging winds and heavy rain rather than tornadoes and large hail.

By late afternoon into early evening, the severe weather risk will push eastward into the Golden Horseshoe and Eastern Ontario. The good news is that the risk should wind down quickly after sunset, which occurs around 8:00 p.m.

There could still be some leftover showers or weak storms lingering into the evening, especially across Eastern Ontario, but the threat for damaging weather will rapidly diminish once the sun goes down.

We’ll continue to monitor this setup closely and provide updates as new data becomes available. Stay tuned, and as always, make sure you have a way to receive alerts if storms develop in your area.

Download our free app to instantly get any Environment Canada alerts and our own custom notifications pushed to your phone. We are planning to go live to cover any storms that develop throughout the day on Tuesday. Please subscribe to our YouTube channel here so you can be notified when we go live.

REGIONAL BREAKDOWN

April 26, 2025

🌪️ ‘Tornado Tuesday’: Confidence Continues to Build For Significant Severe Thunderstorms Next Week in Ontario ⛈️

April 26, 2025/ Adam Skinner

TUESDAY, APRIL 29, 2025: Confidence continues to build for the risk of significant severe thunderstorms and tornado activity this Tuesday. Since our first article posted on Friday morning where we discussed this potential, we’ve continued to carefully monitor a strengthening trend on the forecast models. And at this point, we’re trending up from what initially looked like an Enhanced Risk (3/5), towards an isolated Significant Risk (4/5) based on the latest data. What we’re expecting at this point is isolated strong-to-significant severe thunderstorms across parts of Southwestern and Central Ontario Tuesday afternoon & evening that could possibly extend into the GTHA and parts of Eastern Ontario overnight, depending on the timing and speed of the cold front.

A lot can still change four days out but the consistency of the model data is why we here at InstantWeather have been discussing this for several days and why even Environment Canada has issued a preliminary forecast map today, discussing some of the risks on Tuesday including 100km/h damaging wind gusts and 2-4cm hail as you can see in the image below.

Environment Canada, in their first forecast map for this event has not mentioned a tornado risk. This is likely because we’re four days out but based on the data that we’ll be reviewing below, we’d be very surprised if they did not add a tornado risk in their forecast update tomorrow. Along with this forecast map, they wrote:

”A cold front will track east across northeastern and southern Ontario. By the afternoon, severe thunderstorms may develop with the main threats being strong wind gusts and large hail.”

🔎Model Data Review

In the image above, we’re looking at the latest “NAM” model data for 5pm on Tuesday and what we’re reviewing is the “Supercell Index”. This gives us an idea of how potent the environment is for rotating storms, which can lead to damaging wind gusts, large hail, flooding, intense lightning and in some cases, tornadoes. In our previous article, we only saw an orange supercell risk which is roughly an “Enhanced” risk level (3/5). However, in the latest data we are now seeing the colour red, which is hinting at the potential for a “Significant” risk level (4/5).

And in the image below, we see what the “Supercell Index” looks like at 8pm from the same “NAM” model, continuing the strong environment into the evening hours and extending it further into Eastern Ontario.

It’s still quite early but we’re now finally getting some higher quality data from the NAM model at 12km resolution and what you’re seeing above is simulated or “Future Radar” of how the event might play out. It’s still quite early and this could certainly change but it’s interesting to watch it evolve day-by-day. With this model run, the storms start to develop on the Lake Huron shoreline near the Kincardine and Goderich areas around 5pm. We do see some development up by Britt as well around that time. Again, this is just estimated and we could see a new solution to how this plays out each and every day leading up to Tuesday.

By 8pm in the image above, the simulated NAM future radar is suggesting we could see several potent supercells tracking through parts of Southwestern and Central Ontario. In previous model runs, we have seen a large line of storms as well, which in some cases can limit the tornado risk. Although, we could end up dealing with multi-cell supercells with an environment this strong and those can most certainly produce strong, isolated tornadoes.

And in this potential scenario from the NAM model, we still the storms expanding and tracking through deep Southwestern Ontario, Central Ontario and perhaps into parts of Eastern Ontario by 11pm. Typically, the later in the evening we get, the less we daytime heating we have to increase the severity of these storms but with how strong this environment is, it could be a late night for many of us and we’ll certainly be livestreaming as long as it takes to ensure everyone stays informed and safe.

If you’d like to get notified when we start livestreaming, subscribe to our YouTube channel for free and hit the bell icon to get notified when we go live.

And to get notified of any rotation detected, funnel cloud reports, tornado reports and Environment Canada watches & warnings, download our free mobile app InstantWeather on your phone or tablet.

🤔Final Thoughts:

If this trend continues and this system does not decide to weaken all of the sudden (here’s hoping it does), Tuesday continues to look like a strong or potentially significant severe thunderstorm risk. All modes of severe weather could be on the table with damaging wind gusts, torrential rain, isolated flooding, large hail, intense lightning and the potential for isolated tornadoes, some of which could be strong. Here’s hoping that it weakens into a marginal risk or vanishes all together!

Having said that, please begin to review your storm safety plan and start discussing the potential for rescheduling your Tuesday afternoon/evening plans.

More details ASAP.

Disclaimer: By using our services and any associated content, this means you implicitly agree to use the services and data available as is with no warranty issued or implied and should be used for informational purposes only. Any use of this data for decision making processes is done at the sole risk of the end user. Do not reproduce or disseminate our forecasts and content without explicit consent of Instant Weather, Inc.

April 25, 2025

🌪️ ‘Tornado Tuesday’ Might Make a Return in Southern Ontario Next Week ⛈️

April 25, 2025/ Adam Skinner

TUESDAY, APRIL 29, 2025: As I write this discussion (2am on Friday, April 25th, 2025), we’re quite a few days away from Tuesday, April 29th, 2025. Having said that, I’ve been carefully monitoring this strengthening trend on the forecast models for several days now and seeing them consistently suggesting an enhanced risk (3/5) for severe thunderstorms across much of Southern Ontario with the potential for isolated tornado activity. From Windsor, up through Barrie and perhaps even reaching parts of Eastern Ontario and the GTHA.

Typically, five days out is a lifetime for forecasting severe weather. Having said that, in rare circumstances you can see these strong environments coming from a mile away and this looks like this could be one of those events. Especially when we have a lot of data supporting the risk, which we’ll discuss further down the page.

Could this all change? You betcha. After more than a decade of forecasting severe weather in Ontario and across Canada, I’m no stranger to the potential for a “bust”. I could write this article and the entire system could vanish from the weather models. Tuesday could end up being just another typical spring day. Here’s hoping that’s the case. If, however, that is not the case and the trends we’re seeing in the models are correct, this is the type of event that requires getting the word out well in advance so that alternative plans can be considered and you can review your safety plan with your loved ones.

FRIDAY, APRIL 25, 2025: I should probably mention that we will have a risk for isolated thunderstorms today (Friday) and there is a marginal (low) risk for severe storms in deep southwestern Ontario later this afternoon and into the evening hours. Briefly severe hail and strong wind gusts are possible. At this point, it doesn’t look particularly intense but we’ll be keeping a close eye on it, nonetheless.

🔎Reviewing Models & Available Data For Tuesday

Typically, we like to compare the data from several different model systems. In this case, we’ll compare the American model, the European model and our own Canadian model. In the image above, we’re looking at the American model and what we’re reviewing is the severe weather “energy” that the storms are going to have available to them. The highest levels reaching almost 2,500 (in yellow/orange), which puts this event in the ‘Enhanced 3/5’ category, in my personal opinion.

For context, we can have marginal severe weather with energy levels as low as 500. And on the high-end, CAPE can reach as high as 5,000+ in the most extreme cases. So we’re somewhere in the middle, with totals potentially reaching greater than 1,000 and less than 3,000, at least, at this point.

Above is the Euro model, showing similar strong values to the American model in the deep southwest at 2pm. But, as you’ll see below, the energy progresses further east as we approach 5pm on Tuesday.

Above, we’ve got the 5pm timeframe from the Euro model. Showing organized energy values in place for the expected thunderstorms in the afternoon and evening hours.

While we’re taking a look at the European model, one interesting product they have is an estimated lightning density over several hours. As you can see in red, orange yellow and blue, quite a lot of thunderstorms are expected throughout the afternoon and into the evening hours, taking advantage of all that storm energy we discussed previously.

Below, let’s take a look at the Canadian energy for Tuesday. For some reason, the data looks really blocky. Not sure why PivotalWeather.com (the model provider we’re using for these images) is processing the Canadian model this way but perhaps, it’s coming that way directly from Environment Canada.

Regardless, a similar trend is showing up on the Canadian model that we’re seeing on both the European and American models. And with that, we have what is considered “model agreement”. And it’s not just these three models, other forecasting products called ‘Ensembles’ have 30+ model members and the vast majority are showing a strong severe thunderstorm risk for Tuesday.

This Canadian model image above is for 2pm on Tuesday. And similar to the European model data where we showed two separate timestamps (2pm and 5pm), this energy will push east, through the Barrie area and potentially into the GTHA and parts of Eastern Ontario through the afternoon and evening hours. Energy values look similar to the other two models, supporting the potential for an Enhanced Risk of severe thunderstorms.

Some other data worth noting in the image below is from the Storm Prediction Center (SPC) in Norman, Oklahoma. Not surprisingly, they are already showing a risk map for Tuesday, which they typically only show this far out when there is a strong system expected and a lot of agreement within the weather models.

You can see that southwestern Ontario gets highlighted in this risk area from Windsor, through Chatham-Kent and Sarnia, cutting off just shy of London. Having said that, the SPC’s only job is to forecast for the US. And as we’ve seen historically with them over the past decade, if they’re showing an extended range forecast that highlights parts of Southern Ontario, we could be in for quite the storm system much further into the Province than is shown below.

And in the final image below, we’re looking at a Machine Learning (AI) based severe weather estimation from the US. In this case, they cut off the data at the international border but by simply using your imagination, it’s clear that Southern Ontario is included in this risk region.

🤔Final Thoughts:

If these trends continue and this system does not decide to vanish from all the models suddenly (here’s hoping it does), Tuesday is shaping up to be a strong or potentially significant severe thunderstorm risk. All modes of severe weather could be on the table with damaging wind gusts, torrential rain, isolated flooding, large hail, intense lightning and the potential for isolated tornadoes, some of which could be strong. Here’s hoping that it weakens into a marginal risk or vanishes all together!

Having said that, now would be a good time to start reviewing your storm safety plan and discussing your plans for Tuesday if this system does decide to show up and affect Southern Ontario.

April 08, 2025

Southern Ontario: School Bus Cancellations and Closures for Tuesday, April 8, 2025

April 08, 2025/ Alannah Campbell

Please refresh your page every few minutes to receive the latest update

Cancellation & Closure Map (English Public and Catholic Schools)

Please note: School board boundaries are a rough estimate. Don’t use this map to determine what school board or weather zone you live in as accuracy isn’t guaranteed.

Green = No Cancellations
Red = Cancellations (Click for More Details)
Purple = School Closures (Click for More Details)

List of Cancellations & Closures

English Public and Catholic Schools

Near North Public & Nipissing-Parry Sound CathoIic: Bussing for all weather corridors are cancelled today.
Renfrew County Public & Renfrew County Catholic: Zone 4 Madawaska area transportation services only are cancelled.

French Schools

Le Conseil scolaire public du Nord-Est de l’Ontario (CSPNE) & Conseil scolaire catholique Franco-Nord: Bussing for all weather corridors are cancelled today.

April 07, 2025

'Snow Day' Forecast: Heavy Snow Likely to Cancel School Buses in Parts of Southern Ontario on Tuesday

April 07, 2025/ Brennen Perry

For an updated list of school bus cancellations & school closures, please visit our live article: https://instantweatherinc.com/article/2025/4/8/bus-cancellations

As we move into April, the chances of school bus cancellations continue to shrink with each passing day, especially as we begin to leave winter weather behind. However, winter isn’t done with us just yet. A late-season blast of snow could bring another round of disruptions to parts of Central and Eastern Ontario, with snowfall totals potentially reaching up to 25 cm over the next 24 hours.

snowfall forecast

The greatest potential for school bus cancellations lies in the northern sections of Central and Eastern Ontario, where snowfall warnings are currently in effect from Environment Canada. Areas most at risk include the Near North region—covering East Parry Sound and North Bay—as well as North Hastings under Tri-Board, and Renfrew County.

In these regions, the chance of a snow day is estimated at over 75%. However, while conditions are certainly favourable, the expected snowfall amounts sit right at the borderline for cancellations, so there isn’t enough confidence to push the probability up to 90%.

In the Ottawa region, even though a snowfall warning is also in place, the area is predominantly urban and has a higher tolerance for winter conditions when it comes to school transportation decisions. Historically, it takes a significant snowfall event to warrant widespread cancellations. Because of this, the probability has been set at a lower 25%.

That said, some weather models are showing the potential for more than 20 cm of snow in the area, and if those more aggressive forecasts come to pass, Ottawa’s snow day risk could increase sharply overnight.

Moving further south and west, the likelihood of school bus cancellations drops noticeably. Snowfall totals in these areas are expected to be much lower and likely won't reach the levels needed to trigger cancellations.

An exception to this could be communities along the Lake Huron shoreline. In these areas, heavier lake-effect snow bands may develop overnight, especially when combined with strong wind gusts, creating blowing snow and reduced visibility. Because of this, we've assigned a slight 25% chance of cancellations in those zones.

Meanwhile, no significant impacts are expected across the Greater Toronto Area (GTA) or Deep Southwestern Ontario. These regions are forecast to receive only a dusting of snow at most, with many areas likely to see little to no accumulation over the next 24 hours. As a result, we aren’t anticipating any school bus cancellations in these parts of the province.

Disclaimer: Instant Weather has zero authority when it comes to bus and school closures.

It is completely up to the school boards, bus companies, local authorities, and parents to decide what is best for their children. This is our best guess based on our forecast.

April 07, 2025

The Never-Ending Winter Continues for Southern Ontario; Snowy System Could Dump Up to 25cm by Tuesday

April 07, 2025/ Brennen Perry

Residents across Southern Ontario, especially in the snowbelt regions, have certainly had their fair share of winter weather this season. From intense snow squalls back in December to the crippling ice storm that hit parts of Central Ontario just last month, it's no wonder that many are ready to say goodbye to winter.

Unfortunately, it seems that Mother Nature didn’t get the memo. Spring-like weather remains out of sight for at least the next week. Instead, the region is facing below-seasonal temperatures, with many areas struggling to reach the freezing mark during the day. On top of that, a fast-moving weather disturbance is currently affecting Northeastern Ontario with heavy snow. This system is expected to push into Southern Ontario late Monday as a cold front makes its way through the region.

Snowfall will intensify overnight and continue into Tuesday morning. The heaviest bands are expected across northern portions of Central Ontario and through the Ottawa Valley. Snowfall totals in these areas could easily exceed 15 cm, with some locations possibly seeing as much as 25 cm.

Elsewhere in Southern Ontario, lake enhancement and lake effect snow behind the system could lead to locally higher amounts—anywhere from 5 to 15 cm is possible around Lake Huron and along the southern shores of Georgian Bay.

Strong wind gusts of up to 80 km/h are also expected Monday evening into the early overnight hours around Georgian Bay, Lake Huron, and parts of Central Ontario. These gusts may create blowing snow and significantly reduce visibility at times.

More concerning, though, is the impact these winds could have on restoration efforts in areas still reeling from last month’s devastating ice storm. With nearly 50,000 Hydro One customers still without power after 10 days, additional outages are possible as the already fragile infrastructure struggles under the pressure of these gusty conditions.

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

As of Monday evening, heavy snow continues to fall across the Sudbury and North Bay regions, both of which have seen a significant dumping of snow throughout the day. By the time conditions begin to improve later this evening, localized snowfall totals will likely surpass 20 cm.

Further south, a sharp cold front is pushing a line of heavy snow across Southern Ontario over the next few hours. Along with the sudden drop in temperatures, this front could bring a quick burst of intense snowfall, leading to brief whiteout conditions and rapid accumulation.

Temperatures are still hovering just above freezing ahead of the front, which should help limit how much of the snow sticks at first, as the wet snow may melt upon contact with the relatively warm ground.

**ESTIMATED WIND GUSTS**- MAP FROM WEATHERBELL

Another concern this evening will be the development of strong wind gusts near Lake Simcoe and extending into parts of the Golden Horseshoe. Wind speeds could reach 60 to 80 km/h in localized areas.

While those wind speeds wouldn’t normally cause widespread issues, the combination of gusty winds and heavy snow could lead to pockets of blowing snow and reduced visibility, especially on the roads.

This area is also still recovering from the recent ice storm, with ongoing power restoration efforts in regions like Simcoe County, Peterborough, and the Kawartha Lakes. The added strain from tonight’s strong winds could cause further damage to the already weakened power grid in those communities.

After midnight, the focus of the heaviest snow will shift eastward into the Ottawa Valley. Persistent, moderate to heavy snow is expected across the region, especially in and around the City of Ottawa. One key area we’ll be closely monitoring is just west of Ottawa, where forecast models are showing the potential for a pocket of very heavy snowfall.

Communities including Algonquin Park, Barry’s Bay, Pembroke, and Petawawa could be directly impacted by this locally intense band of snow. If it shifts slightly east, it may sneak into Ottawa itself—something that could have a major effect on the Tuesday morning commute. Snowfall rates in this band may exceed 5 cm per hour, leading to near-whiteout conditions.

Additionally, more localized lake-effect snow bands could develop off Lake Huron and Georgian Bay early Tuesday. Based on current guidance, one of these bands may impact parts of Huron and Perth counties, with a small chance of reaching the London area, though whether or not London sees any snow will depend on exactly where the band sets up. Some weaker snow activity is also expected near the southern shores of Georgian Bay, including places like Owen Sound, Meaford, and Collingwood.

By Tuesday morning, snowfall will begin to taper off from west to east across the region. The Ottawa Valley will continue to see steady snow past sunrise, although it should begin to lighten up by early afternoon.

Lingering lake effect snow flurries may continue near Lake Huron and Georgian Bay, but are also expected to wind down by late morning as the system finally pulls away.

**ESTIMATED WIND CHILL** - MAP FROM WEATHERBELL

In addition to the snow, Tuesday will bring a blast of bitterly cold Arctic air to much of Southern Ontario. This late-season cold snap will make it feel especially harsh for those heading out in the morning. Once the wind chill is factored in, it could feel like the -20s across parts of Central Ontario.

Make sure to dress warmly, especially if you've already switched to a spring wardrobe. It might be time to dig out that heavy winter coat once again.

The frigid temperatures also pose an added risk for anyone still without power following the ice storm. Be sure to check in on friends, family, and neighbours who may be vulnerable to the cold, and if needed, make use of warming centres set up in the hardest-hit communities.

The highest snowfall totals from this system are expected in the northern sections of Central and Eastern Ontario, including places like Sudbury, North Bay, northern Muskoka, Algonquin Park, Pembroke, Renfrew, and Ottawa. These areas are likely to receive 15 to 25 cm of snow in total, including the accumulation that began earlier on Monday.

Elsewhere in Central Ontario and extreme Eastern Ontario, along with areas east of Lake Huron, snowfall totals are expected to fall in the 5 to 15 cm range. The wide range is due to uncertainty about how much snow will stick, as the heaviest snowfall is forecast while temperatures hover near or just above freezing. Affected areas include Grand Bend, Goderich, Kincardine, Grey-Bruce, Collingwood, Simcoe County, Muskoka, Bancroft, Brockville, and Cornwall.

For much of Southern Ontario, less than 5 cm is expected, with the Golden Horseshoe likely seeing no more than a dusting. In Deep Southwestern Ontario, including Windsor, Chatham, and Sarnia, little to no accumulation is expected from this system.

April 03, 2025

⚠️ Flood Warnings Issued for Kitchener, Cambridge and More Ontario Communities on Thursday ☔️

April 03, 2025/ Adam Skinner

***NOTE: YOU CAN CLICK ON THE image TO OPEN An interactive map***

Heavy rainfall and rapid snowmelt are triggering rising water levels across much of Southern Ontario, prompting multiple flood warnings and watches being issued since this past Friday. Conservation authorities and the Ministry of Natural Resources (MNR) have issued alerts for various watersheds, warning that saturated ground conditions and increased runoff may lead to localized flooding. Residents in affected areas should remain vigilant as rivers and streams swell, with the risk of minor to moderate flooding in low-lying regions.

New Flood Warnings

The Grand River Conservation Authority (GRCA) is issuing a Flood Warning message for the City of Kitchener and the City of Cambridge. The Flood Warning message previously issued for West Montrose is being upgraded to Flood Warning Zone 2. The Flood Warning messages previously issued for Grand Valley, Waldemar, Drayton, the Village of Conestogo, New Hamburg, and Ayr remain in effect.

Weather forecast

Temperatures in the watershed have increased to double digits above freezing overnight and are expected to remain high for the remainder of the day. A mixed precipitation event, including snow, freezing rain, and rain, began yesterday and continued overnight throughout the watershed. This has resulted in approximately 40 to 80 mm of total precipitation and increased runoff throughout the watershed.

Flood Warning Message for the City of Kitchener

The Grand River is expected to overflow its banks midday Thursday, April 3, increasing the risk of flooding in low-lying areas. Municipal flood coordinators in the City of Kitchener have been advised to notify affected properties and monitor conditions.

Flood Warning Message for the City of Cambridge

The Grand River is expected to overflow its banks near Water Street/Highway 24 on midday Thursday, April 3. Municipal flood coordinators in the City of Cambridge have been advised to notify affected properties and monitor conditions.

Flood Warning Message for West Montrose

River flows are expected to reach Flood Warning Zone 2 in West Montrose the afternoon of Thursday, April 3. Municipal flood coordinators in the Township of Woolwich have been advised to notify affected properties and monitor conditions. Residents are encouraged to refer to the guide on the GRCA’s website for information regarding flood warning zones.

Flood Warning Message for Grand Valley and Waldemar

River flows are expected to exceed channel capacity and peak midday Thursday, April 3. Municipal flood coordinators in Grand Valley and Waldemar have been advised to notify affected properties and monitor conditions.

Flood Warning Message for Drayton

River flows are expected to reach Flood Warning Zone 1 in Drayton on Thursday, April 3, during the morning. Municipal flood coordinators in the Township of Mapleton have been advised to notify affected properties and monitor conditions. Residents are encouraged to refer to the guide on the GRCA’s website for information regarding flood warning zones.

Flood Warning Message for the Village of Conestogo

River flows are expected to reach flooding thresholds in the Village of Conestogo midday Thursday, April 3. Municipal flood coordinators in the Township of Woolwich have been advised to notify affected properties and monitor conditions.

Flood Warning Message for New Hamburg

River flows are expected to reach Flood Warning Zone 2 in New Hamburg midday Thursday, April 3. Municipal flood coordinators in the Township of Wilmot have been advised to notify affected properties and monitor conditions. Residents are encouraged to refer to the guide on the GRCA’s website for information regarding flood warning zones.

Flood Warning Message for Ayr

River flows are expected to reach Flood Warning Zone 2 in Ayr on the morning of Friday, April 4. Municipal flood coordinators in the Township of North Dumfries have been advised to notify affected properties and monitor conditions. Residents are encouraged to refer to the guide on the GRCA’s website for information regarding flood warning zones.

This message will remain in effect until 12 p.m. on Saturday, April 5, 2025.

Flood Warnings

MNR Districts:

- Aurora, Midhurst, Owen Sound – *Flood Warning* (April 2, 2025, 12:30 PM)

- Minden, Parry Sound, Bracebridge – *Flood Warning* (March 28, 2025, 2:30 PM)

- Peterborough, Bancroft (Burnt and Black Rivers) – *Flood Warning* (March 28, 2025, 12:00 AM)

Conservation Authorities:

- Grand River – *Flood Warning* (April 3, 2025, 8:30 AM) NEW

- Nottawasaga Valley – *Flood Warning* (April 1, 2025, 1:30 PM)

- Otonabee Region – *Flood Warning* (April 2, 2025, 1:00 PM)

Flood Watches

MNR Districts:

- Peterborough, Bancroft – *Flood Watch* (March 27, 2025, 10:00 AM)

Conservation Authorities:

- Ausable Bayfield – *Flood Watch* (April 1, 2025, 3:00 PM)

- Cataraqui Region – *Flood Watch* (April 1, 2025, 11:30 AM)

- Crowe Valley – *Flood Watch* (April 2, 2025, 2:00 PM)

- Essex Region – *Flood Watch* (April 1, 2025, 4:30 PM)

- Grey Sauble – *Flood Watch* (April 1, 2025, 11:00 AM)

- Hamilton Region – *Flood Watch* (March 31, 2025, 10:30 AM)

- Hamilton Region (High Great Lakes Level) – *Flood Watch* (April 1, 2025, 3:30 PM)

- Kawartha Region – *Flood Watch* (March 31, 2025, 12:00 AM)

- Kettle Creek – *Flood Watch* (April 2, 2025, 4:00 PM)

- Lower Trent – *Flood Watch* (April 2, 2025, 4:30 PM)

- Maitland Valley – *Flood Watch* (April 2, 2025, 10:30 AM)

- Mississippi Valley – *Flood Watch* (April 2, 2025, 4:00 PM)

- Niagara Peninsula – *Flood Watch* (April 2, 2025, 10:00 AM)

- Rideau Valley – *Flood Watch* (March 27, 2025, 4:15 PM)

- Saugeen Valley – *Flood Watch* (April 1, 2025, 12:00 AM)

- South Nation River – *Flood Watch* (March 28, 2025, 1:30 PM)

- St. Clair Region – *Flood Watch* (April 2, 2025, 11:00 PM)

Watershed and Shoreline Conditions Statements

Water Safety Statements:

- Catfish Creek – *Watershed Conditions Statement – Water Safety* (April 2, 2025, 8:30 AM)

- Ganaraska Region – *Watershed Conditions Statement – Water Safety* (April 1, 2025, 3:30 PM)

- North Bay – *Watershed Conditions Statement – Water Safety* (March 28, 2025, 3:00 PM)

- Pembroke – *Watershed Conditions Statement – Water Safety* (March 28, 2025, 12:00 PM)

- North Bay-Mattawa – *Watershed Conditions Statement – Water Safety* (March 28, 2025, 2:30 PM)

- Raisin Region – *Watershed Conditions Statement – Water Safety* (March 24, 2025, 10:00 AM)

Flood Outlook Statements

- Central Lake Ontario – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 12:00 AM)

- Credit Valley – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 11:30 AM)

- Halton Region – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 12:00 AM)

- Lake Simcoe Region – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 4:00 PM)

- Long Point Region – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 3:30 PM)

- Lower Thames Valley – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 2:00 PM)

- Quinte (Inland Lakes and Rivers) – *Watershed Conditions Statement – Flood Outlook* (March 27, 2025, 12:00 PM)

- Toronto and Region – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 1:30 PM)

- Upper Thames River – *Watershed Conditions Statement – Flood Outlook* (April 1, 2025, 2:30 PM)

- **Shoreline Conditions Statement – Storm Surge:**

- Catfish Creek – *Shoreline Conditions Statement – Storm Surge* (December 11, 2024, 12:00 AM)

Flood Risks and Safety Tips

With continued snowmelt and upcoming rainfall, many rivers and streams remain at risk of rising beyond their banks, especially in central and eastern Ontario. The combination of warm temperatures and precipitation is accelerating runoff, leading to swollen waterways with reduced capacity to handle additional rainfall. Minor flooding in low-lying areas is expected, with localized road closures possible.

- Stay informed by monitoring local weather forecasts, special weather statements, and emergency alerts.

- Avoid low-lying areas prone to flooding and never attempt to drive through flooded roads.

- Secure outdoor belongings that could be carried away by rising waters.

- If you live in a flood-prone area, prepare an emergency kit with essentials in case of evacuation.

Final Thoughts:

As flood warnings and watches continue across parts of Southern Ontario, it's important for residents in affected areas to stay alert and prepared. The combination of rapid snowmelt, saturated ground conditions, and forecasted rainfall means that water levels could rise quickly, increasing the risk of localized flooding. Keep an eye on weather updates, follow official advisories, and take precautions to protect your home and safety. If you live in a flood-prone area, now is the time to review your emergency plan. Stay safe, stay informed, and let’s hope for drier days ahead!

April 03, 2025

Southern Ontario: School Bus Cancellations and Closures for Thursday, April 3, 2025

April 03, 2025/ Alannah Campbell

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Cancellation & Closure Map (English Public and Catholic Schools)

Please note: School board boundaries are a rough estimate. Don’t use this map to determine what school board or weather zone you live in as accuracy isn’t guaranteed.

Green = No Cancellations
Red = Cancellations (Click for More Details)
Purple = School Closures (Click for More Details)

List of Cancellations & Closures

English Public and Catholic Schools

Dufferin-PeeI Catholic: Buses to St Andrew, St Peter, St Benedict and RF Hall are cancelled
Kawartha Pine Ridge Public & Peterborough Victoria Northumberland Clarington Catholic: There continues to be some transportation disruptions this morning following the ice storm. Please visit www.stsco.ca for Peterborough, Northumberland, and Clarington or www.mybustoschool.ca for details. The following schools remain closed:
NORTHUMBERLAND/QUINTE WEST:
Camborne Public School, Plainville Public School, & Roseneath Centennial Public School
CITY AND COUNTY OF PETERBOROUGH:
Buckhorn Public School, Crestwood Intermediate School and Crestwood Secondary School, Norwood District Public School, Norwood Intermediate School and Norwood District High School, & Warsaw Public School
CITY OF KAWARTHA LAKES:
St. Luke Catholic Elementary School
Near North Public & Nipissing-Parry Sound CathoIic: Busses are cancelled for the Redbridge/Thorne weather zone.
PeeI Public: All transportation to RF Hall SS is cancelled today due to cancellations in Dufferin County.
Rainbow Public & Sudbury Catholic: Morning busses are cancelled for Sudbury, Espanola, and Massey. Busses will run this afternoon.
Renfrew County Public & Renfrew County Catholic: All busses are cancelled.
Simcoe County Public & Simcoe Catholic: Busses are cancelled for Muskoka. The following schools remain closed:
SIMCOE COUNTY PUBLIC:
Brechin PS, East Oro PS, Forest Hill PS, Goodfellow PS, Guthrie PS, Holly Meadows ES, Marchmont PS, Rama Central PS, Severn Shores PS, Shanty Bay PS, Uptergrove PS, WR Best Memorial PS & All City of Orillia Schools.
SIMCOE MUSOKA CATHOLIC:
All schools in Muskoka and Orillia.
Trillium Lakelands: Transportation is not running in Zones 4 and 5 due to the ice storm. The following schools remain closed:
ZONE 1:
Glen Orchard Public School & Honey Harbour Public School,
ZONE 3:
Cardiff Elementary School
ZONE 4:
Bobcaygeon Public School, Fenelon Township Public School, Lady Mackenzie Public School, Ridgewood Public School & Woodville Elementary School
ZONE 5:
Dr. George Hall Public School, Jack Callaghan Public School, & Mariposa Elementary School
Upper Grand Public & Wellington CathoIic: Busses are cancelled for North Wellington (Division 3) and Dufferin County & Robert F. Hall (Division 4).

French Schools

Conseil des écoles publiques de l’Est de l’Ontario (CEPEO): Busses are cancelled for Renfrew County
Conseil catholique MonAvenir: École élémentaire catholique Samuel-de-Champlain remains closed.
Conseil scolaire public du Grand Nord de l’Ontario (CSPGNO): Morning busses are cancelled for Sudbury, Espanola, and Massey. Busses will run this afternoon.
Le Conseil scolaire public du Nord-Est de l’Ontario (CSPNE) & Conseil scolaire catholique Franco-Nord: Busses are cancelled for the Redbridge/Thorne weather zone.

April 02, 2025

'Ice Day' Forecast: Parts of Southern Ontario May See School Bus Cancellations on Thursday Due to Lingering Freezing Rain Impacts

April 02, 2025/ Brennen Perry

For an updated list of school bus cancellations & school closures, please visit our live article: https://instantweatherinc.com/article/2025/4/3/bus-cancellations

***NOTE: SOME SCHOOLS ARE CLOSED DUE TO THE EARLIER ICE STORM. PLEASE CONSULT WITH YOUR LOCAL SCHOOL BOARD FOR A DETAILED LIST OF SCHOOL CLOSURES***

A messy weather system is currently sweeping across Southern Ontario, bringing a mix of freezing rain, ice pellets, and heavy snow. As temperatures begin to rise later this evening and into Thursday morning, much of the precipitation is expected to transition to plain rain, gradually improving road conditions across the region.

Although freezing rain is not expected to persist into the Thursday morning commute, some roads—especially in rural parts of Central and Eastern Ontario—could still be icy. This lingering risk means there’s still a chance that school bus transportation could be impacted in a few regions, depending on how quickly conditions improve overnight.

It’s important to note that localized school closures remain in effect across some of the hardest-hit communities in Central Ontario. These closures are mainly due to ongoing power outages caused by the earlier ice storm. For the most accurate and up-to-date information, please check directly with your local school board, as the situation continues to evolve.

One area has already confirmed a cancellation for Thursday: Trillium Lakelands District School Board has announced that school transportation will be cancelled in both City of Kawartha Lakes zones. Ongoing recovery efforts and the continued lack of hydro have made transportation logistics extremely difficult. Communication towers remain down in the area, meaning bus drivers are unable to safely coordinate with bus companies, leading to the decision to cancel.

Looking further north, the highest probability of school bus cancellations lies in the Sudbury, North Bay, and Parry Sound regions. In these areas, freezing rain is expected to continue later into the night, only switching over to rain closer to the morning hours. As a result, road conditions are likely to remain icy by morning. The school boards covering these areas are known for being cautious, particularly when it comes to winter weather impacts on rural roads.

For Central and Eastern Ontario, the chances of school bus cancellations are more mixed, ranging between 25% and 50%, depending on the specific region and timing of the transition to rain. Boards that cover more rural or higher elevation areas will be more likely to see issues, while those in the southern sections of the region—where the switchover to rain will happen earlier in the evening—will have a longer window for melting and road improvement overnight.

At this point, the outcome could easily go either way. That’s why confidence remains low when it comes to predicting widespread cancellations despite the messy setup. While conditions are expected to improve quickly overnight, uncertainty lingers, especially for rural zones where icy backroads often remain a hazard well after the main part of the storm has passed.

Disclaimer: Instant Weather has zero authority when it comes to bus and school closures.

It is completely up to the school boards, bus companies, local authorities, and parents to decide what is best for their children. This is our best guess based on our forecast.

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The Tornado: A Narrow but Confirmed Touchdown Near Lakeside

Timeline: Forecast Leading Up to the Tornado

🔎Model Data Review

🤔Final Thoughts:

🔎Reviewing Models & Available Data For Tuesday

🤔Final Thoughts:

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Cancellation & Closure Map (English Public and Catholic Schools)

List of Cancellations & Closures

English Public and Catholic Schools

French Schools

New Flood Warnings

Weather forecast

Flood Warning Message for the City of Kitchener

Flood Warning Message for the City of Cambridge

Flood Warning Message for West Montrose

Flood Warning Message for Grand Valley and Waldemar

Flood Warning Message for Drayton

Flood Warning Message for the Village of Conestogo

Flood Warning Message for New Hamburg

Flood Warning Message for Ayr

Flood Warnings

Flood Watches

Watershed and Shoreline Conditions Statements

Flood Outlook Statements

Flood Risks and Safety Tips

Final Thoughts:

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Cancellation & Closure Map (English Public and Catholic Schools)

List of Cancellations & Closures

English Public and Catholic Schools

French Schools

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