Southern Ontario: ‘Snow Day’ Forecast for Friday, January 9, 2026

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Milder weather is expected across Southern Ontario throughout Friday, with temperatures remaining well above the freezing mark.

Any precipitation that develops on Friday will fall as plain rain and is not expected to create any travel issues or hazardous road conditions.

Because of this, all of Southern Ontario carries less than a 5 percent chance of a snow day on Friday.

It looks like homework is in the forecast for tonight!

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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.

Southern Ontario: ‘Snow/Fog Day’ Forecast for Thursday, January 8, 2026

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While no major winter weather conditions are expected to impact travel across Southern Ontario on Thursday morning, weather conditions may still be less than ideal in some areas. Patchy fog is expected to develop overnight and could linger into the early morning hours, particularly in rural regions.

If fog becomes dense enough, it could significantly reduce visibility on roadways. This raises the possibility of a few scattered school bus cancellations, mainly in parts of Southwestern, Central and Eastern Ontario. These regions tend to be more sensitive to fog-related impacts, especially where rural routes, open fields and low-lying areas allow visibility to drop quickly.

That said, confidence remains fairly low when it comes to pinpointing exactly where cancellations may occur. Fog events can be highly localized, and small shifts in wind or temperature overnight can make the difference between clear conditions and dense fog by morning. Because of that uncertainty, this is not a high-confidence forecast for any one region.

To account for this, we have assigned a widespread 25 percent chance for what could be considered a “fog day” on Thursday in areas where school boards have historically shown a willingness to cancel when visibility becomes an issue. This includes Lambton and Chatham-Kent under the Lambton Kent District School Board, Middlesex, Elgin and Oxford counties within the Thames Valley District School Board, and all regions covered by the Avon Maitland District School Board.

This 25 percent zone also includes Wellington and Dufferin counties under the Upper Grand District School Board, most of the Bluewater District School Board, excluding in-city routes in Owen Sound, Parry Sound and East Parry Sound within the Near North District School Board, and North and Central Hastings, along with North and Central Lennox and Addington under Tri-Board Student Transportation Services. While most of these regions will likely see buses running as normal, a few localized cancellations are possible depending on where fog is most persistent.

Outside of these areas, the rest of Southern Ontario carries a low to very low chance of school bus cancellations. A surprise decision cannot be completely ruled out, but confidence is low that fog will become dense enough or widespread enough to justify cancellations in these regions.

Urban school boards across the Golden Horseshoe and the Ottawa area are especially unlikely to see any disruptions. Fog rarely leads to cancellations in highly urbanized regions, where road networks are better lit, more heavily travelled and less dependent on long rural bus routes.

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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.

Southern Ontario: School Bus Cancellations and Closures for Wednesday, January 7, 2026

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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 as well as Duffern County buses to Robert F. Hall CSS are cancelled today

• Kawartha Pine Ridge Public & Peterborough Victoria Northumberland Clarington Catholic: Transportation is cancelled in Northumberland County today

• PeeI Public: Some gravel or rural roads in Caledon might not be serviced today. Monitor https://businfo.stopr.ca/Cancellations.aspx for updates

• Simcoe County Public & Simcoe Catholic: Busses are cancelled in the South Zone.

• Thames Valley Public & London CathoIic: Busses are cancelled in Oxford County.

• Tri-Board: All school bus and taxi transportation is cancelled today.

• Upper Canada Public & Eastern Ontario CathoIic: All transportation is cancelled

• Upper Grand Public & Wellington CathoIic: All school taxis and buses in Division 3 (North Wellington) and Division 4 (Dufferin County and Robert F. Hall) will not be operating today.

French Schools

• Conseil des écoles publiques de l’Est de l’Ontario (CEPEO): All CTSE busses are cancelled. CTSO busses are cancelled for Kingston, Trenton, Brockville, Kemptville, Marionville and Presscott-Russell.

• Conseil catholique MonAvenir: Busses are cancelled for some schools in Simcoe

• Conseil scolaire de district catholique de l'Est Ontarien (CSDCEO): All busses are cancelled.

• Conseil des écoles catholiques de langue française du Centre-Est: Busses are cancelled for Kingston, Trenton, Brockville, Kemptville, Marionville and Presscott-Russell.

• Conseil scolaire catholique Providence: Busses are cancelled in Simcoe South and Oxford.

• Conseil scolaire Viamonde: Busses are cancelled in Simcoe South and Oxford.

‘Snow Day’ Forecast: Some Parts of Southern Ontario May See a Third Day of Bus Cancellations on Wednesday

For an updated list of school bus cancellations & school closures, please visit our live article: https://instantweatherinc.com/article/2026/1/7/bus-cancellations

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A messy system has been delivering a whiplash of winter weather across Southern Ontario throughout the day on Tuesday. Precipitation has ranged from freezing rain to ice pellets, with conditions expected to transition over to heavier snow in some areas through the evening.

While the core of this system is forecast to wind down later this evening and into the early overnight hours, its impacts are expected to linger into Wednesday morning. For regions that have dealt with prolonged periods of freezing rain, there is little indication of a meaningful warmup overnight. This means any ice that has formed on untreated surfaces is unlikely to melt, leaving roads, sidewalks and driveways slippery heading into the morning commute.

Because of this, we have fairly high confidence that some school bus cancellations will occur on Wednesday, particularly in rural areas with extensive backroad networks. These routes can remain icy well after precipitation ends, especially when temperatures stay below freezing. In addition to icing concerns, thick fog is expected to develop in parts of Southwestern Ontario overnight, which could further reduce visibility and contribute to cancellations or delays.

The highest chance for a snow or ice day includes Kingston, South Frontenac, South and Central Lennox and Addington, and Belleville under Tri-Board Student Transportation Services, along with Peterborough and Northumberland counties within the Kawartha Pine Ridge District School Board.

These regions tend to be among the most sensitive to poor backroad conditions due to their large rural coverage. They are also expected to see freezing rain linger the longest, leaving less time for road crews to fully clear conditions before the morning bus run. As a result, we have assigned these areas a 75 percent chance of bus cancellations.

Much of the remaining rural portion of Central Ontario into Southwestern Ontario falls into the toss-up category. We expect several school boards in this zone to keep buses off the roads, but decisions will likely come down to highly localized road conditions and how much additional icing occurs overnight.

This includes the remainder of Tri-Board Student Transportation Services, the Madawaska region within the Renfrew County District School Board, most of the Trillium Lakelands District School Board excluding North Muskoka, and the Simcoe North weather zone under the Simcoe County District School Board.

Rural school boards across Southwestern Ontario may also be impacted by the development of thick fog overnight, combined with lingering icy conditions in higher elevation areas that saw freezing rain earlier Tuesday.

Because of this, we have also assigned a 50 percent chance to several boards in this region, although confidence here is slightly lower. Outcomes will depend on how dense and widespread the fog becomes by morning.

This group includes Dufferin and Wellington counties within the Upper Grand District School Board, Grey County under the Bluewater District School Board, Perth County for the Avon Maitland District School Board, and Middlesex and Oxford counties within the Thames Valley District School Board.

A slight chance, around 25 percent, has been assigned to the rural portions of the Ottawa Valley, including areas covered by the Upper Canada District School Board and the Renfrew County District School Board. Icing here has been more limited, making cancellations questionable, but a few isolated decisions cannot be ruled out if conditions deteriorate overnight.

We have also assigned a 25 percent chance to the remainder of Simcoe County, along with Georgina under the York Region District School Board. These areas are more urban and typically maintain a higher threshold for cancellations, so decisions will depend on whether road conditions are poor enough early Wednesday morning to justify keeping buses off the roads.

In Southwestern Ontario, a 25 percent chance has been given to the Waterloo Region District School Board, Guelph within the Upper Grand District School Board, Elgin County under the Thames Valley District School Board, Lambton County for the Lambton Kent District School Board, Huron County within the Avon Maitland District School Board, and southern Bruce County under the Bluewater District School Board.

Patchy fog is possible in these regions, but confidence in its extent is lower, and several of these boards are less likely to cancel based on fog or marginal backroad issues alone.

Elsewhere across Southern Ontario, including Ottawa and the more urban school boards throughout the Golden Horseshoe and into Deep Southwestern Ontario, the chance of bus cancellations remains low.

That said, if there are any surprises, they may come from parts of Deep Southwestern Ontario, including Windsor, Sarnia and Chatham. Some forecast guidance suggests fog could extend into these areas overnight, which may prompt a small number of unexpected cancellations if visibility becomes an issue.

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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.

Southern Ontario: School Bus Cancellations and Closures for Tuesday, January 6, 2026

**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

• BIuewater Public & Bruce-Grey Catholic: All busses are cancelled EXCEPT for Zone 7 (Teeswater, Lucknow, Ripley)

• Dufferin-PeeI Catholic: Buses in STOPR Zone 3 and buses to St. Andrew, St. Peter, St. Benedict, and Robert F. Hall CSS are cancelled today due to forecasted road and weather conditions.

• Durham Public & Durham Catholic: DSTS has cancelled all transportation for today due to inclement weather.

• HaIton Public & Halton Catholic: Transportation services are cancelled in all Zones.

• Kawartha Pine Ridge Public & Peterborough Victoria Northumberland Clarington Catholic: Bus and transportation service is cancelled to ALL schools in the STSCO jurisdiction for the day.

• PeeI Public: All Transportation in Zone 3 is cancelled today.

• Renfrew County Public & Renfrew County Catholic: Zone 4 Madawaska area transportation services ONLY are cancelled due to the afternoon weather forecast.

• Simcoe County Public & Simcoe Catholic: All busses are cancelled.

• Tri-Board: Transportation is cancelled in Tri-Board’s Prince Edward County, Belleville & Quinte West, Centre Hastings, South Lennox & Addington, Central Lennox & Addington weather zones today.

• Trillium LakeIands: Transportation to schools is not operating in Zone 1, 4, and 5 today.

• Upper Grand Public & Wellington CathoIic: All school taxis and buses will not be operating today.

• York Public & York Catholic: School bus and taxi transportation has been cancelled Region-wide today.

French Schools

• Conseil des écoles publiques de l’Est de l’Ontario (CEPEO): Busses are cancelled for Trenton

• Conseil catholique MonAvenir: Busses are cancelled for schools in Durham, York, Wellington, Simcoe, Peterborough, and Halton

• Conseil des écoles catholiques de langue française du Centre-Est: Busses are cancelled for Trenton.

• Conseil scolaire catholique Providence: Busses are cancelled for York, Simcoe, Halton, Durham and Bruce-Grey Regions

• Conseil scolaire Viamonde: Busses are cancelled for York, Simcoe, Halton, Durham, and Bruce-Grey Regions

Southern Ontario Faces Ice Threat Then Snow as Fast Moving Winter System Disrupts Tuesday Travel

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A fast changing winter system is expected to sweep through much of Southern Ontario during the day on Tuesday, bringing a messy mix of precipitation types and rapidly changing conditions. While this is not expected to be a blockbuster storm on its own, the combination of freezing rain followed by snow could still create localized impacts, especially during the afternoon and evening hours.

The first part of this system will arrive Tuesday morning and early afternoon, with freezing rain becoming the dominant concern for several regions. Widespread freezing rain is expected to develop across the higher elevations northwest of the GTA, extending into areas north of Lake Simcoe and along the Lake Ontario shoreline from Peterborough eastward toward Kingston. These elevated regions tend to hang onto colder air longer, making them more vulnerable to icing during marginal setups like this one.

Freezing rain is expected to begin developing across parts of Southwestern Ontario east of Lake Huron, including the Kitchener area and the Dundalk Highlands, by the late morning hours on Tuesday. From there, the freezing rain shield is forecast to spread north and eastward through the afternoon, reaching areas around Lake Simcoe such as Barrie, along with York Region, Durham Region, Kawartha Lakes, Peterborough and eventually Kingston.

In some locations, the precipitation may initially fall as ice pellets during the early afternoon before transitioning over to freezing rain for a few hours. This could help slightly limit ice accretion at first, but any freezing rain will still make untreated roads, sidewalks and elevated surfaces quite slick as temperatures remain near or below freezing.

For the GTA, the freezing rain threat looks more limited, but it cannot be ruled out entirely. There could be an hour or two of freezing rain during the afternoon, especially in the northern parts of the region, before precipitation transitions over to light snow by the evening. Meanwhile, areas in Deep Southwestern Ontario and the Niagara region are expected to remain mostly on the rain side of this system, with temperatures hovering in the low single digits above freezing for much of the event.

One of the more unusual aspects of this system is what happens after the freezing rain ends. While ice accretion amounts are expected to generally remain manageable, in the range of 2 to 5 millimetres for areas northwest of the GTA into Simcoe County and eastward through Peterborough and Kingston, there will not be a quick or clean warm-up. Instead, colder air is expected to surge back in, overpowering the warm layer aloft.

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As this colder air deepens, precipitation is forecast to transition back to snow by the early evening and continue into the overnight hours across Central and Eastern Ontario, as well as the higher elevations northwest of the GTA. This changeover could happen fairly quickly once it begins, leading to periods of steady snowfall through Tuesday night.

Snowfall totals from this second phase of the system are expected to range from 5 to 10 centimetres across many of the same areas that experienced freezing rain earlier in the day. This includes parts of Simcoe County, Kawartha Lakes, Peterborough and areas toward Kingston, as well as elevated terrain northwest of the GTA.

While neither the ice accretion nor the snowfall amounts are particularly extreme on their own, the combined impact could be more significant. Even light ice accretion can weaken tree branches and add extra weight to power lines, and when followed by several centimetres of heavy, wet snow, the risk of isolated power outages and downed branches increases.

Elsewhere, including the GTA, regions east of Lake Huron and parts of northern Central and Eastern Ontario, snowfall totals are expected to be lighter, generally in the 2 to 5 centimetre range. This should still be enough to create slick travel conditions Tuesday evening and overnight, especially as temperatures drop back below freezing.

For the Ottawa region, this system looks less impressive overall. Precipitation amounts appear limited, and snowfall totals may struggle to reach the 2 centimetre mark by the time everything wraps up.

As always with systems like this, small changes in temperature can make a big difference in precipitation type and impacts. Drivers should be prepared for rapidly changing road conditions throughout the day on Tuesday, especially in areas that see freezing rain followed by accumulating snow.

‘Snow (Ice) Day’ Forecast: Risk of Freezing Rain on Tuesday Could Cancel School Buses in Parts of Southern Ontario

For an updated list of school bus cancellations & school closures, please visit our live article: https://instantweatherinc.com/article/2026/1/6/bus-cancellations

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

A messy and potentially disruptive system is expected to move through Southern Ontario on Tuesday, bringing with it the risk of several hours of freezing rain developing from the late morning into the afternoon.

Environment Canada has issued widespread freezing rain warnings and special weather statements ahead of this system, highlighting the threat of icing beginning Tuesday morning and continuing through much of the day. With freezing rain notoriously difficult to deal with on untreated surfaces, there is growing concern that some school boards may opt to cancel buses, particularly across rural areas northwest of the Greater Toronto Area and into portions of Central and Eastern Ontario.

What makes this event especially tricky from a school transportation perspective is the timing. The bulk of the freezing rain is not expected to begin until after the morning bus run has already wrapped up. That means any cancellations would need to be made proactively, based largely on Environment Canada alerts and the expectation of deteriorating conditions during the afternoon dismissal. Historically, that level of proactiveness can vary quite a bit from one school board to another.

Because of that uncertainty, we have capped the highest probability at 50 percent, reflecting the fact that this could truly go either way. This 50 percent zone includes Middlesex and Oxford counties under the Thames Valley District School Board, Perth County within the Avon Maitland District School Board, Wellington and Dufferin counties for the Upper Grand District School Board, and the Kincardine, Hanover and Meaford regions under the Bluewater District School Board. These areas are more rural in nature, tend to respond more cautiously to freezing rain threats, and are currently covered by freezing rain warnings. While no single region stands out as a sure thing for cancellations, we do have fairly strong confidence that at least a few boards will declare an “ice day” on Tuesday.

We have also included Peterborough and Northumberland counties under the Kawartha Pine Ridge District School Board, along with the southern portions of Tri-Board Student Transportation Services, in the 50 percent category. These areas are currently under special weather statements rather than full warnings, but these school boards have a history of being particularly proactive when freezing rain is involved. In some cases, even a special weather statement can be enough to prompt cancellations.

A broader area has been assigned a 25 percent chance, covering much of Southwestern Ontario and extending into parts of Central and Eastern Ontario. This includes the Greater Essex County District School Board, the Lambton Kent District School Board, London and Elgin County within the Thames Valley District School Board, Huron County under the Avon Maitland District School Board, Owen Sound, Southampton and the Bruce Peninsula for the Bluewater District School Board, Waterloo Region, Guelph under the Upper Grand District School Board, the Simcoe County District School Board, North and South Kawartha Lakes under the Trillium Lakelands District School Board, and the remaining portions of Tri-Board. In these areas, freezing rain is either expected to be patchy or brief, but given the timing and potential for slick roads, a few surprise cancellations cannot be ruled out.

Outside of this zone, including the more urban school boards across the Golden Horseshoe, the Ottawa Valley and Northeastern Ontario, the chance of school bus cancellations drops to low or very low. In some cases, these regions are simply too far removed from the core freezing rain threat, as is the case for parts of Northeastern Ontario and the Ottawa Valley. In other cases, the boards are highly urbanized and typically require more widespread or severe icing before cancellations are considered.

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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.

Southern Ontario: School Bus Cancellations and Closures for Monday, January 5, 2026

**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

• Avon MaitIand Public & Huron-Perth CathoIic: There are several cancellations, please visit this link for more details: https://hpsts.mybusplanner.ca/Alerts

• BIuewater Public & Bruce-Grey Catholic: All busses are cancelled.

• Kawartha Pine Ridge Public & Peterborough Victoria Northumberland Clarington Catholic: Bus and transportation service is cancelled to ALL schools in the STSCO jurisdiction for the day.

• Tri-Board: All school bus and taxi transportation is cancelled in the Tri-Board Student Transportation Services area today.

French Schools

• Conseil des écoles publiques de l’Est de l’Ontario (CEPEO): Busses are cancelled for Kingston and Trenton

• Conseil catholique MonAvenir: Busses are cancelled for schools in Durham and Peterborough

• Conseil des écoles catholiques de langue française du Centre-Est: Busses are cancelled for Kingston and Trenton

• Conseil scolaire catholique Providence: Busses are cancelled in Bruce-Grey

• Conseil scolaire Viamonde: Busses are cancelled in Bruce-Grey

Quick Blast of Heavy Snow May Impact the Morning Commute in Southern Ontario With Up to 15cm of Snow on Monday

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It has certainly been a busy start to 2026 across parts of Southern Ontario, especially in the snowbelt regions. Relentless snow squalls over the past week have brought widespread travel disruptions along with staggering snowfall totals, with some areas picking up an incredible 50 to 100cm of snow in a relatively short period of time.

While we managed to catch a bit of a break through the weekend, that quieter stretch will be short-lived. The first full week of the new year is shaping up to be an active one, with several rounds of messy winter weather expected to move through Southern Ontario over the next few days.

The next system arrives early Monday in the form of a fast-moving Alberta clipper. Unfortunately, the timing could not be much worse. With many people heading back to work and school after the holiday break, this system is expected to sweep through during the heart of the Monday morning commute.

Snow is expected to break out across Southwestern Ontario and quickly expand northeastward into Central Ontario and the Golden Horseshoe. While this will not be a major snowfall event by snowbelt standards, the intensity and timing of the snow could still cause notable travel issues.

Snowfall totals are not expected to be extreme, especially compared to what areas east of Lake Huron and southeast of Georgian Bay have been dealing with recently.

However, widespread amounts of 8 to 15cm are possible in the hardest hit regions. The key factor here is that much of this snow is expected to fall within just a few hours, which significantly increases its impact compared to a longer duration, lighter snowfall.

This clipper system is expected to move through fairly quickly, with conditions gradually improving by Monday afternoon or early evening. However, the active pattern will not take long to reload.

A second system is already lining up to arrive beginning Tuesday afternoon and continuing into Wednesday. There is still some uncertainty surrounding the exact track of this system, which will ultimately determine who sees snow, ice, or rain.

At this point, areas closer to Lake Erie and Lake Ontario appear most at risk for a period of freezing rain, potentially followed by heavy rain as warmer air pushes northward. Further north into Central and Eastern Ontario, colder air may hold on longer, leading to another round of accumulating snow with totals in the 5 to 15cm range possible.

Looking even further ahead, we are also monitoring two additional systems that could impact Southern Ontario toward the end of the week and into the upcoming weekend. Early indications suggest much of Southern Ontario may start out on the rain side of the system on Friday. However, colder air could work its way south by Saturday, allowing rain to transition back to snow.

It is far too early to pin down exact impacts, but this system will have access to a large amount of moisture. If colder air arrives sooner or proves more stubborn than currently expected, the risk for significant snowfall or even prolonged freezing rain would increase.

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

Turning back to Monday’s clipper, the first bands of snow are expected to enter Southern Ontario from the west overnight into the early morning hours. Snow should develop along the Lake Huron and Georgian Bay shoreline by mid-morning, becoming steady and occasionally heavy.

By late morning, snow will spread eastward into Central Ontario and the Golden Horseshoe. With this occurring during peak commuting hours, expect slower travel and reduced visibility, especially for those who may be easing back into winter driving after the holidays.

Blowing and drifting snow may further reduce visibility, particularly in areas east of Lake Huron where deep snowbanks are already in place. Even moderate winds will be enough to cause drifting in open areas and along rural roadways.

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

Conditions are expected to deteriorate the most by the late morning hours around Lake Simcoe and into parts of the Greater Toronto Area. During this time, hourly snowfall rates could briefly reach 2 to 3cm, which would qualify as heavy snow. This can quickly overwhelm road crews and lead to rapidly deteriorating road conditions.

As the system continues east, light snow will begin reaching Eastern Ontario while snowfall starts to taper off closer to Lake Huron. Areas along the Lake Erie shoreline and into Deep Southwestern Ontario will largely be spared from the worst of the snow, with the bulk of the moisture tracking north of these regions.

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

Snowfall intensity will gradually decrease through the early afternoon as the system moves away. Steadier snow will linger across Central and Eastern Ontario, while areas such as Kitchener and the GTA see snow slowly taper off as the system lifts north of Lake Simcoe.

Some lingering light snow could persist into the early evening hours for parts of Eastern Ontario, including areas near Kingston and Brockville, before finally coming to an end.

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There is fairly strong agreement among forecast models when it comes to overall snowfall placement. Most guidance supports a swath of 10 to 15cm stretching from Grey-Bruce through Central Ontario, into the northern GTA, Peterborough, and extending eastward toward Kingston. This zone may also extend into parts of southern Northeastern Ontario.

For our forecast map, we have opted to lower the top range slightly to 8 to 15cm rather than a more aggressive 10 to 15cm. This accounts for the possibility of some underperformance near the southern edge of the snow band, especially through parts of Toronto. Clippers are notorious for sharp gradients and occasional dry slots, which could keep totals lower in some locations.

Across the Goderich to Kitchener and Hamilton corridor, snowfall amounts of 5 to 8cm look reasonable. That said, if the system ends up being drier than expected, some locations may struggle to reach the 5cm mark.

Further south into Sarnia, London, and the Niagara Region, amounts should generally stay below 5cm. Windsor and Leamington may see little more than a trace, if any snow at all.

In the Ottawa Valley, northern sections closer to the Quebec border, including Pembroke, Ottawa, and Cornwall, are expected to see around 2 to 5cm. Areas further south, such as Bancroft, Smiths Falls, and Brockville, could pick up closer to 5 to 8cm.

Some recent model runs have hinted at heavier snow pushing a bit further north in Eastern Ontario, so the potential for localized overperformance cannot be ruled out.

PRECIP TYPE - MAP FROM WEATHERBELL

Once snow winds down Monday evening, conditions will briefly improve before the next system approaches. Current guidance suggests a messy and complex setup developing Tuesday afternoon and lasting into Wednesday.

Unlike the clipper, this system will involve a stronger battle between warm and cold air. This raises the risk for a band of freezing rain to set up somewhere across Southern Ontario, at least for a few hours.

At this point, it looks like a lower-impact freezing rain scenario where areas transition from freezing rain to plain rain as warmer air moves northward. However, higher resolution models are only just coming into range, and it is possible that the cold air proves more stubborn than currently expected.

As the system exits overnight into Wednesday, a broader area of heavier snow could develop across Northeastern, Central, and Eastern Ontario. Where this snow band ultimately sets up remains uncertain, but snowfall amounts in the 5 to 15cm range are possible.

We will have a much clearer picture of that system once Monday’s clipper moves through and we can assess how the atmosphere responds.

Beyond that, yet another round of unsettled weather is possible toward the end of the week and into the weekend. While heavy rain currently looks like the main concern, colder air arriving sooner could flip the script toward heavy snow. This remains highly preliminary, but it reinforces the message that winter is not easing up anytime soon.

‘Snow Day’ Forecast: Heavy Snow May Delay Return From Holiday Break for Some Students in Southern Ontario on Monday

For an updated list of school bus cancellations & school closures, please visit our live article: https://instantweatherinc.com/article/2026/1/5/bus-cancellations

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

After a two-week break from school across Southern Ontario, it’s understandable that many students and parents are ready for a return to normal with the first official school day of 2026. Unfortunately, the timing is far from ideal. An approaching Alberta Clipper is expected to sweep across the region overnight Sunday into Monday, delivering a burst of heavy snow right during the height of the morning commute.

Environment Canada has already begun issuing widespread snowfall warnings ahead of this system, highlighting the potential for 10 to 15 cm of snow by Monday, along with periods of reduced visibility. With snow falling at a steady rate through the early morning hours, it’s quite possible that winter break may be extended by at least one more day in some parts of Southern Ontario.

The highest confidence for a snow day sits squarely within the Bluewater District School Board. This entire region is expected to see the most snowfall from the Alberta Clipper, on top of already significant snowpack left behind by persistent lake effect snow over the past week. Wind gusts approaching 40 to 50 km/h may also lead to areas of blowing snow, especially in open and rural locations.

With heavy snow beginning overnight and continuing into Monday morning, conditions are likely to deteriorate quickly. Because of this, we are leaning strongly toward school bus cancellations across the entire Bluewater region.

Surrounding school boards fall into a more uncertain category. Northern portions of Huron and Perth counties under the Avon Maitland District School Board, Wellington and Dufferin counties within the Upper Grand District School Board, and the Simcoe West, Central and South weather zones under the Simcoe County District School Board have all been assigned a 50 percent chance of a snow day.

These boards tend to operate with a higher threshold for cancellations, and while 10 to 15 cm of snow is impactful, it sits close to that decision line. Confidence here will depend heavily on snowfall rates during the morning commute and how quickly conditions deteriorate.

Farther south and east, the heavy snow threat will extend into portions of the Greater Toronto Area, including Peel Region, York Region, the City of Toronto and Durham Region. While these areas are expected to see accumulating snow, the more urban nature of these boards typically results in fewer cancellations unless snowfall becomes extreme. As a result, these regions carry a very low to low chance of school bus cancellations on Monday.

To the north and east of the core snow zone, we have assigned a 25 percent chance for several school boards that cover large rural areas and are more sensitive to winter travel conditions.

This includes Parry Sound and East Parry Sound within the Near North District School Board, Simcoe North under the Simcoe County District School Board, South Muskoka along with North and South Kawartha Lakes under the Trillium Lakelands District School Board, Peterborough and Northumberland counties within the Kawartha Pine Ridge District School Board, and Central Hastings, Belleville and Central and South Lennox and Addington under Tri-Board Student Transportation Services.

While we are leaning toward a normal school day for most of these regions, uncertainty remains given the potential impact on untreated rural roads during the morning commute.

Elsewhere across Southern Ontario, including the Ottawa Valley, Deep Southwestern Ontario and areas along the Lake Erie shoreline, the chance of a snow day appears fairly unlikely. In the Ottawa Valley, snow is expected to arrive later in the day, after the morning bus run. For regions closer to Lake Erie, snowfall amounts should remain minimal as the system tracks farther north, limiting impacts.

As always with Alberta Clippers, small shifts in timing or intensity could make a noticeable difference Monday morning. We’ll continue to monitor conditions closely and provide updates as needed, but for now, the return to school may be delayed for some, while others should prepare for a snowy start to the week.

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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.

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

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

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

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

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

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

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

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

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

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

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

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

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

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

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

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

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

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

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

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

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

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

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

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

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

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

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

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

Weathering the Storm: How to Prepare For an Ice Storm

In advance of the ice storm anticipated to impact the province, we at Instant Weather want to make sure that everyone is ready in the event of potential widespread and long term power outages. The impact of an ice storm is not just dependent on the amount of ice accretion, but also the winds associated with the storm. This is summarized using the Sperry-Piltz Ice Accumulation (SPIA) Index shown below.

It is important to be prepared for these situations so we have put together a list of items you should have on hand in case of an emergency:

• Flashlight (windup or battery operated)

• Radio (windup or battery operated)

• Extra batteries

• Portable cell phone charger

• Water (2 litres per person per day)

• Non-perishable canned or dried food

• Manual can opener

• Blankets

• Candles and matches or lighters

• First aid kit and any prescriptions/medical items

• List of emergency numbers

• Cash

• Gasoline

Not sure what kind of food to have ready? Dried food like rice and pasta along with canned tuna can go a long way. Other items such as bread and granola bars are good for fibre and non-refrigerated fruits like bananas, oranges and apples help break up the high-sodium content found in dried foods. Another staple for many are storm chips. For water, an easy way to store a large amount is to fill a bathtub and use the water for drinking, cooking, and flushing toilets.

Since ice storms occur during the winter and early spring months, keeping warm is a major concern during extended power outages from ice storms. Electric baseboard heaters and space heaters will not work. However, natural gas furnaces will still work, but electrical components such as the blower, which forces the warm air through the vents, will not. There are some propane heaters that can be used indoors, but be careful because outdoor propane heaters produce carbon monoxide, making them very dangerous to use inside a home.

Another item worth adding to your emergency kit arsenal is a generator. Generators are available in a variety of sizes and capacities based on individual needs. There are a few things to consider when picking a generator: type, power and additional features.

There are home standby generators that are permanently in place and start up automatically when the power goes out. These units are large and can be quite expensive. There are also smaller, portable generators that either run strictly on gas or on either gas or propane (dual fuel). There is an added benefit of running your generator on propane as it less expensive to run.

Every generator has two power ratings: starting watts and running watts. In order to determine the power of generator you need, you first need to determine what appliances will be running. In the event of an emergency, you may find that the only necessities are the fridge and furnace fan.

It is EXTREMELY important to not run a generator in your house due to the risk of carbon monoxide poisoning.

With proper planning and preparation, everyone should be able to get through the stress that comes with extended periods without power. In the case of an ice storm, it’s important to stay indoors and reduce unnecessary travel. Also, we recommend not clogging up emergency lines with non-emergencies. Your power will be back before you know it!

End-of-Year Major Winter Storm to Bring Dangerous Ice Storm and Blizzard Conditions Across Southern and Northeastern Ontario Starting Sunday

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As we close out 2025, the final few days are shaping up to be very messy and potentially dangerous. A complex and powerful winter storm is expected to impact Ontario between Sunday and Monday, bringing ice storm conditions to a wide swath of Central, Eastern and Northeastern Ontario.

With significant and prolonged freezing rain expected, widespread and long-lasting power outages are likely in the hardest hit areas. Ice accretion of up to 20mm is possible, and unfortunately, the regions most at risk include many of the same areas that were hit hard by last March’s major ice storm. In some locations, the power grid remains fragile, which raises additional concern.

Further north, the story will shift to heavy snow across much of Northeastern Ontario. Long-lasting blizzard conditions are possible here, with snowfall totals potentially exceeding 50cm by the time the storm finally winds down on Tuesday.

This system will also bring the risk of severe wind gusts across both Southern and Northern Ontario on Monday. Areas closest to the shorelines of the Great Lakes will be at the greatest risk, with damaging wind gusts in excess of 90 km/h possible. There may even be some isolated pockets, mainly in the Niagara region, that approach 100 km/h.

Southwestern Ontario will be largely unaffected by the first phase of the storm. Temperatures here will rise steadily on Sunday, peaking in the double digits by late afternoon or evening. Rain will fall steadily through Sunday and into early Monday. However, conditions will change rapidly as temperatures plunge Monday morning, creating a potential flash freeze as all that rainfall quickly freezes on roads and other surfaces.

Later on Monday, strong wind gusts will combine with steady, moderate snowfall around Lake Huron and Georgian Bay. Blizzard conditions could develop during the afternoon and evening as visibility drops and blowing snow becomes intense.

PRECIP TYPE - MAP FROM WEATHERBELL

The storm will begin to take shape late Sunday morning as the first bands of precipitation spread into Northeastern Ontario and parts of Southwestern Ontario. This will initially include some light freezing rain extending from London through Kitchener and Barrie.

TEMPERATURE - MAP FROM WEATHERBELL

Sunday afternoon will be heavily dependent on the position of the freezing line, which is expected to slowly expand northeastward. Areas to the southwest will gradually climb above freezing and escape the worst of the icing, while regions farther northeast remain locked below zero.

By around midday, most of Central and Eastern Ontario is expected to remain well below freezing. Higher elevation areas northwest of the GTA will hover close to the freezing mark, including Hamilton, Kitchener, Guelph and Orangeville. How long the cold air remains trapped at the surface will play a major role in how impactful the icing becomes in places like the Kitchener area.

Meanwhile, Deep Southwestern Ontario, including Windsor, will already be sitting in the mid single digits. Heavy rain will be ongoing here, but there will be no winter storm impacts during the day on Sunday.

PRECIP TYPE - MAP FROM WEATHERBELL

As Sunday afternoon progresses, the freezing rain shield will expand northward into the North Bay area and the Ottawa Valley. The heaviest icing during this time is expected to focus around Lake Simcoe.

Locations such as Bracebridge, Lindsay, Orillia, Peterborough, Barrie, York Region, Kitchener and Orangeville appear likely to see the worst icing on Sunday afternoon. Precipitation rates will be quite heavy, allowing ice to accumulate rapidly on roads, trees and power lines.

At the same time, Southwestern Ontario, including the Niagara region, will see heavy rain, with some embedded non-severe thunderstorms possible. Rainfall totals could be significant, with some localized areas exceeding 50mm by Monday morning.

At the same time, Southwestern Ontario, including the Niagara region, will see heavy rain, with some embedded non-severe thunderstorms possible. Rainfall totals could be significant, with some localized areas exceeding 50mm by Monday morning.

Flooding could be a concern as frozen ground has a lower ability to absorb the rain.

PRECIP TYPE - MAP FROM WEATHERBELL

As we move into Sunday evening, the freezing rain zone will become very expansive as the system rapidly intensifies. Intense icing is expected from Sault Ste. Marie through Sudbury and North Bay and into Central and Eastern Ontario.

Meanwhile, colder and more entrenched air across Northeastern Ontario will allow precipitation to switch over to heavy snow. Areas from Wawa to Kapuskasing will see snowfall rates increase significantly.

TEMPERATURE - MAP FROM WEATHERBELL

By late Sunday evening, uncertainty will increase across southern portions of Central and Eastern Ontario as temperatures hover very close to the freezing mark. This includes Barrie, Orillia, Muskoka, the Kawarthas, Peterborough and Kingston. If cold air proves even slightly more resilient than currently expected, these regions could remain below freezing overnight and continue to experience ice storm conditions.

In Deep Southwestern Ontario, it will feel almost surreal for late December, with temperatures climbing into the double digits even around midnight.

PRECIP TYPE - MAP FROM WEATHERBELL

Overnight Sunday into early Monday, heavy snowfall will expand farther south across Northeastern Ontario as colder air continues to advance. Areas including Sault Ste. Marie, Timmins and the Cochrane corridor are expected to transition from freezing rain to heavy snow.

This transition is especially concerning for the power grid, as heavy snow may accumulate on top of ice-coated trees and power lines. That combination could lead to significant damage, particularly in more remote and heavily forested areas.

For the Sudbury to Ottawa Valley corridor, freezing rain is expected to continue through the overnight hours with ice accumulation steadily increasing. This region is likely to see some of the worst overall impacts due to the length of time spent under freezing rain.

TEMPERATURE - MAP FROM WEATHERBELL

By late Monday morning, the next phase of the storm will unfold in the form of a flash freeze across Deep Southwestern Ontario. Rapidly falling temperatures will cause any remaining moisture to freeze quickly on untreated surfaces, creating extremely hazardous travel conditions.

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As freezing rain ends across Central and Eastern Ontario and temperatures drop by Monday afternoon, the true extent of the damage will become clear. Current data suggests the hardest hit areas may include Kawartha Lakes, Peterborough, Haliburton, Bancroft, Tweed, Kaladar, Renfrew, Perth and Ottawa. Ice accretion in these regions may range from 15 to 20mm, with localized pockets potentially approaching 25mm.

In the Ottawa Valley, temperatures may not rise above freezing at all before the flash freeze arrives. This would lock ice in place for an extended period, worsening impacts. Farther south, a brief window above freezing may help slightly reduce overall damage.

A broader area of Central and Eastern Ontario, along with higher elevations northwest of the GTA and parts of Northeastern Ontario, can expect between 10 and 15mm of ice. This includes Brockville, Kitchener, Guelph, Newmarket, Barrie, Muskoka, Parry Sound, North Bay, Sudbury and Sault Ste. Marie.

Ice amounts will decrease closer to Lake Ontario and away from higher terrain. Between 5 and 10mm is possible from Kingston through the northern GTA and higher elevations around Hamilton and Grimsby. Less than 5mm is expected for Oshawa, Mississauga, Hamilton and Meaford. Little to no icing is expected near Lake Huron and Lake Ontario, where temperatures remain above freezing for most of the event.

PRECIP TYPE - MAP FROM WEATHERBELL

While freezing rain will end, hazardous conditions will continue. By late Monday morning, rain will change to heavy snow around Lake Huron and Georgian Bay. Strengthening winds of 70 to 90 km/h will create dangerous travel conditions and likely meet blizzard criteria.

Combined with the flash freeze, widespread road closures are likely east of Lake Huron and into Northeastern Ontario. Travel should be avoided in these regions.

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The strongest wind gusts are expected during the morning and afternoon on Monday before slowly easing in the evening. Areas exposed to the lakes will see the worst winds, with gusts of 95 to 110 km/h possible across the Niagara region and into Prince Edward County.

Near damaging gusts of 85 to 95 km/h are possible along the Lake Ontario shoreline from Kingston through the GTA and Hamilton, as well as along the Lake Erie and Lake Huron shorelines and southeast of Georgian Bay into Simcoe County and Orangeville.

Elsewhere across Southwestern Ontario and southern portions of Central and Eastern Ontario, peak gusts of 75 to 85 km/h are expected. Farther north, including the Ottawa Valley, gusts will generally range from 65 to 75 km/h. While lower, these winds may cause greater damage due to occurring after significant ice accumulation.

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

Conditions will remain treacherous through Monday afternoon with strong winds and persistent snowfall, especially near the lakes, where blizzard conditions continue.

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Snowfall totals associated with the main system will wrap up by Tuesday morning. Central Ontario and parts of Southwestern Ontario east of Lake Huron can expect 5 to 15cm of snow, with localized totals exceeding 15cm near Kincardine, Hanover and Owen Sound due to lake enhancement.

Elsewhere across Southern Ontario, snowfall amounts will generally range from 2 to 5cm.

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In Northern Ontario, snowfall totals will be far more significant. The highest amounts are expected in Cochrane, Timmins, Chapleau and Kirkland Lake, where totals of 50 to 75cm are possible between Sunday evening and Tuesday morning.

A broader swath of Northeastern Ontario, including Wawa and Temiskaming Shores, may see 30 to 50cm. Areas such as Elliot Lake, Sault Ste. Marie and Kapuskasing could receive 20 to 30cm, while North Bay, Sudbury and Manitoulin Island are expected to pick up between 10 and 20cm.

Boxing Day Winter Storm Poised to Deliver Ice Storm Risk and Heavy Snow to Southern Ontario on Friday

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With Christmas now behind us, the focus turns to the final stretch of 2025 as we approach New Year’s next Thursday. And it’s looking like the last seven days of the year will be anything but quiet when it comes to the weather across Southern Ontario.

That active pattern becomes clear very quickly with a looming Boxing Day winter storm expected to bring a messy mix of precipitation. Some areas will see periods of heavy snowfall, while others could be dealing with a potentially damaging ice storm with prolonged freezing rain through much of the day.

For much of Central Ontario, along with parts of the Golden Horseshoe and into portions of Southeastern Ontario, the primary concern will be snowfall. Widespread totals in the 10 to 20 cm range are possible by the end of Friday. The Ottawa Valley is expected to remain on the lower end, generally staying under the 10 cm mark.

The forecast becomes more complicated through Southwestern Ontario, extending through Hamilton and into the Niagara Region. Here, a mix of snow and ice pellets is expected, which will limit snowfall totals but still create hazardous travel conditions.

The freezing rain risk has shifted slightly northward in the latest model guidance, as warmer air aloft is now expected to push deeper into Southern Ontario than earlier projections suggested. This places the Sarnia to London corridor in the bullseye for the highest ice accretion. Freezing rain totals of 10 to 15 mm are possible, which could result in significant power outages and very icy road conditions.

Beyond Friday, attention is already turning to another slow-moving system expected to arrive Sunday and linger into Monday. This system appears to have access to much more moisture compared to Friday’s storm, raising the concern for a prolonged period of freezing rain that could last anywhere from 12 to 24 hours.

What adds to the concern is that current model guidance is focusing this next threat over parts of Central and Eastern Ontario, the same areas that were hardest hit by last winter’s major ice storm. There is still uncertainty with the exact track, and it could shift north or south, but it is something we are watching very closely.

PRECIP TYPE - MAP FROM WEATHERBELL

Before we get ahead of ourselves, the immediate focus remains on Friday’s storm. Precipitation is expected to begin during the early to mid-morning hours as bands move in from the west. Light to moderate snow will spread into Grey-Bruce, Simcoe County, Muskoka and the GTA during this time.

For Windsor, Chatham and Sarnia, light freezing rain is expected to begin by mid-morning. Precipitation may be somewhat scattered at first but will steadily increase in coverage and intensity as the morning progresses.

PRECIP TYPE - MAP FROM WEATHERBELL

By late morning, the worst conditions should be underway, with heavy icing ongoing around Chatham, Sarnia and London. Travel conditions in these areas are expected to deteriorate quickly.

Further north and east, heavy snow will be the main concern across Muskoka, Simcoe County, Peterborough and the eastern GTA, including the City of Toronto.

Between the freezing rain to the southwest and the heavy snow to the north and east, a corridor of ice pellets is expected to develop from the Lake Huron shoreline through Kitchener and into Hamilton.

PRECIP TYPE - MAP FROM WEATHERBELL

Poor conditions will persist into Friday afternoon, with steady snowfall continuing across Central Ontario into Kingston. Wind gusts approaching 40 km/h may lead to localized blowing snow, further reducing visibility at times.

The ice pellet zone may also push further into the GTA, with Toronto potentially switching over to ice pellets for a time. This would limit snowfall totals and keep them closer to the 10 cm range.

Sarnia and London are expected to remain locked into freezing rain through much of the afternoon. There may be some hope for the Chatham area, where temperatures could briefly rise just above freezing and allow a changeover to rain by mid-afternoon. However, this is right on the line and could still go either way. Windsor and Leamington are expected to remain solidly in the rain zone.

PRECIP TYPE - MAP FROM WEATHERBELL

The system is expected to gradually wind down later Friday afternoon and into the early evening. Precipitation will taper off first across western areas, then slowly come to an end across the Golden Horseshoe and Eastern Ontario by late evening.

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Based on the latest data, the highest ice storm concern has been focused on the Sarnia, Lambton, Middlesex and London corridor. While there is still some disagreement on exact intensity, the potential exists for ice accretion exceeding 10 mm, with localized amounts approaching 15 mm.

Communities included in this higher risk zone include Wallaceburg, Sarnia, Petrolia, Thamesville, Lambton Shores, Grand Bend, St. Thomas and London.

Across Essex County, the highest ice accretion is expected in the northern portions of the county, including Windsor and Tilbury. These areas could see 5 to 10 mm of ice before a changeover to rain. Closer to the Lake Erie shoreline, including Leamington, icing should be minimal, generally under 2 mm, as temperatures rise above freezing more quickly.

Further north, freezing rain amounts will be reduced as ice pellets dominate initially, with freezing rain gradually mixing in later. Locations such as Lucan, Exeter, Woodstock, Tillsonburg, Simcoe, Port Colborne and Fort Erie could see a faster transition to freezing rain, with 5 to 10 mm of ice possible following a few hours of ice pellets.

For Huron and Perth counties, including Kitchener, Brantford and Niagara Falls, ice pellets are expected to linger longer. This will limit freezing rain to only a few hours near the end of the storm, with ice accretion generally in the 2 to 5 mm range. Less than 2 mm of icing is expected for Hamilton, Guelph and southern Grey-Bruce.

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On the snowfall side of the storm, the highest totals are expected to range from 10 to 20 cm across Northeastern Ontario, down into Central Ontario and parts of Eastern Ontario.

This includes areas such as Sudbury, North Bay, Parry Sound, Muskoka, Simcoe County, York Region, Toronto, Durham Region, the Kawarthas, Peterborough and Kingston.

Lower snowfall totals are expected in the Ottawa Valley, where amounts of 2 to 5 cm are forecast for Ottawa and 5 to 10 cm from Bancroft into Brockville. This is due to the core of the system’s moisture remaining further south.

South of the heaviest snow band, totals will decrease as ice pellets mix in later in the storm. Grey-Bruce, Orangeville, Guelph and the western GTA are currently expected to see 5 to 10 cm, though some model solutions suggest even less if mixing becomes more dominant.

Even lower snowfall totals are expected east of Lake Huron into Hamilton and Niagara, where less than 5 cm is forecast as ice pellets and freezing rain become the primary precipitation types.

PRECIP TYPE - MAP FROM WEATHERBELL

Once this system exits Friday night, Saturday should bring a brief period of calmer weather. However, that break will be short-lived, as another potentially high-impact winter storm is expected to approach as early as Sunday, possibly arriving in multiple waves.

The overall setup supports the potential for a prolonged area of freezing rain that could remain locked in place into Monday. This raises concern for a significant ice storm event, potentially similar in nature to last winter’s devastating storm across Central and Eastern Ontario.

Those same regions are once again in the early bullseye. While there is still time for this forecast to change, this is the type of setup where residents should begin thinking ahead and preparing for the possibility of extended power outages if the scenario does not improve.

We will continue to monitor this closely and will have a more detailed update once we get through Friday’s storm.

Potential Boxing Day Winter Storm Targets Southern Ontario With Significant Freezing Rain Risk and Up to 15-20cm of Snow

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While winter weather has mostly taken a breather across Southern Ontario over the past week, things are about to turn active again as we head into the final days of 2025.

That change begins on Boxing Day with a messy winter system expected to slide through Southern Ontario. This system will bring a wide range of hazards, including the threat of significant freezing rain in Deep Southwestern Ontario and more widespread snowfall across much of the rest of the region.

There are still some question marks surrounding this storm, particularly when it comes to how strong it ultimately becomes. Some lower-resolution models show a fairly robust system with plenty of moisture to work with. At the same time, higher resolution guidance that is now coming into range is hinting at some drier pockets, which could cause this system to underperform in spots.

Complicating matters further is the fact that this system has the characteristics of an Alberta Clipper. Clippers are notorious for being difficult to forecast since they often lack a deep source of moisture, and small changes can make a big difference in precipitation type and totals.

What we do know at this point is that impacts will vary significantly across Southern Ontario. The highest risk area continues to be Deep Southwestern Ontario, especially the Windsor, Chatham and Sarnia region, which currently sits in the bullseye for prolonged freezing rain.

In these areas, sustained freezing rain could lead to substantial ice accretion on roads, trees and power lines. This would result in dangerous travel conditions and an increased risk of power outages. With over 10mm of icing possible, there is also concern for widespread tree damage as branches struggle under the weight of the ice.

Further north, from areas east of Lake Huron through the Greater Toronto Area and into Central and Eastern Ontario, the primary precipitation type is expected to be snow. Snow will fall steadily through much of the day on Friday with general accumulations of 5 to 15cm by the end of the day. Locally higher amounts approaching 20cm are possible west of Lake Ontario around the Toronto area due to lake enhancement.

PRECIP TYPE - MAP FROM WEATHERBELL

The first bands of precipitation are expected to arrive early to mid-morning on Friday, spreading across Lake Huron into Southwestern Ontario. As the system moves in, it will encounter a stubborn layer of cold air near the surface across Deep Southwestern Ontario, including Windsor, Leamington, Chatham and Sarnia.

At the same time, warmer air will surge in above the surface, creating a classic setup for freezing rain. This warm layer aloft melts the snow into rain, which then freezes on contact with cold surfaces at the ground.

850MB TEMPS (1.5KM ABOVE GROUND) - MAP FROM WEATHERBELL

The biggest challenge with events like this is determining how far north and how deep that warm layer extends. This is the key factor that decides whether precipitation falls as ice pellets or as freezing rain.

Temperatures roughly 1.5km above the surface vary considerably between models. The Canadian model is more aggressive, pushing the warm layer farther north into Southwestern Ontario and even as far as London.

Overall, model consensus places the freezing line somewhere near a Sarnia to London corridor. Areas south of this line are more likely to see freezing rain, while areas to the north will see a mix of ice pellets and snow.

PRECIP TYPE - MAP FROM WEATHERBELL

By the early afternoon, heavier snow will begin spreading into Central Ontario and the Golden Horseshoe as precipitation from Northern Ontario moves southeast across Georgian Bay. At the same time, freezing rain will be ongoing around Windsor, Chatham and Sarnia.

There are indications that temperatures may slowly climb above freezing for southern Essex County, including Leamington and eventually Windsor. There is still disagreement on the exact timing of this changeover, but it appears most likely sometime during the early to mid-afternoon.

If temperatures do rise above freezing, freezing rain would switch to plain rain, and any ice accretion would begin to melt. How quickly this happens will be critical in determining overall impacts. If the warmup is delayed until later in the day or temperatures stubbornly remain below freezing before dropping Friday night again, impacts could be significantly worse.

For areas like Chatham-Kent, Sarnia and St. Thomas, there is growing concern that temperatures may remain below freezing for much of the event. This would allow ice to accumulate for a prolonged period, with over 10mm of accretion possible. Ice amounts of this magnitude are capable of bringing down tree limbs and power lines, potentially leading to power outages that could last for several days.

Hourly snowfall rates (cm) - MAP FROM WEATHERBELL

By mid-afternoon, the heaviest snow will be pushing through the Golden Horseshoe. Some models are showing the potential for lake enhancement along the Lake Ontario shoreline from Niagara through Hamilton and into Toronto. If this develops, snowfall rates could briefly spike to 3 to 5cm per hour compared to the more general 1 to 2cm per hour elsewhere.

It is also important to note that ice pellets may mix in at times, which can limit snowfall totals since ice pellets are denser than snow. This is most likely for areas such as London, Kitchener, Hamilton and Niagara, where conditions are more supportive of mixed precipitation. Areas closer to Toronto and farther north into Central Ontario should see more consistent snow.

Light to moderate snow will also spread into Eastern Ontario by the afternoon and continue into the evening before tapering off around midnight. Confidence in snowfall totals here is lower, but amounts in the 5 to 10cm range appear possible by the end of the day.

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While there is decent agreement on the overall track of this system, fluctuations are still very likely. Freezing rain events are among the most difficult to forecast, and even small temperature changes can have major impacts.

At this time, the highest confidence for the worst impacts remains across the Chatham, Windsor and St. Thomas area, where a persistent band of freezing rain is expected to set up for much of the day on Friday. Some models show up to 20mm of liquid precipitation, though not all of that would freeze on surfaces. For now, we are forecasting over 10mm of ice accretion, with the understanding that an overachieving scenario is still on the table.

For southern Essex County, including Leamington and possibly southern Windsor, ice accretion of 5 to 10mm is possible before a changeover to rain. Because of this transition, overall impacts should be lower compared to areas farther north, where freezing rain may last longer.

Farther north, from Sarnia through London and into Norfolk County, precipitation may begin as ice pellets in the morning before transitioning to freezing rain later in the afternoon or early evening. Ice accretion here could range from 3 to 8mm, depending on how quickly this transition occurs.

A corridor stretching from Goderich through Kitchener, Hamilton and into the Niagara region is expected to start with heavier snow Friday afternoon. Mixing with ice pellets later in the day could reduce snowfall totals, with most areas seeing around 5 to 10cm by the end of the event.

Areas that remain predominantly snow from start to finish include Grey-Bruce, much of Central Ontario, Eastern Ontario and the eastern portions of the GTA. Snowfall totals here should generally range from 10 to 15cm, with localized amounts up to 20cm. In Eastern Ontario, especially closer to the Quebec border, totals may struggle to reach 10cm, making 5 to 10cm a more realistic expectation.

We will continue to monitor the latest data closely and will have a more detailed and refined forecast on Thursday night. That update will provide a clearer breakdown of precipitation types and expected amounts. Be sure to check back for the final forecast.

White Christmas Locked In for Parts of Southern Ontario, While Others Face the Risk of a Green Christmas for 2025

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

As the big day approaches this Thursday, many across Southern Ontario are starting to ask the big question. Will we wake up to that picture-perfect White Christmas, or will the Grinch sneak in at the last minute and snatch it away from right under our noses (and our carrots)?

In some parts of Southern Ontario, especially the snowbelt regions, it might feel like a White Christmas is already wrapped up and sitting under the tree. These areas were absolutely pummelled by relentless snow squalls earlier this month, leaving behind an impressive snowpack.

But for others, it has been a very different story. Some regions managed to dodge the worst of the snow so far this season, and whatever snow did fall has largely melted away thanks to a recent stretch of milder weather.

That sets the stage for a classic Christmas weather showdown. The Grinch, helped along by a few Heat Miser inspired temperature spikes, will try to erase what little snow remains. Jack Frost, however, is waiting in the wings and is expected to take over closer to Christmas. This makes a weak system expected Tuesday into Wednesday the key player, potentially delivering a last minute chance at a White Christmas for some areas.

CURRENT SNOWFALL DEPTH (cm) - MAP FROM WEATHERBELL

We begin by looking at the existing snowpack, which is often the biggest clue in determining where a White Christmas is all but guaranteed. The most impressive snowpack is found east of Georgian Bay through Simcoe County and into Muskoka, Haliburton and Bancroft.

Model estimates suggest a solid 10 to 25cm of snow on the ground here. These models are fairly low resolution and likely underestimate reality, especially since much of this snow fell during intense lake effect events.

There is also a respectable snowpack of around 5 to 15cm in the higher elevations of Southwestern Ontario, particularly northeast of London. These areas have taken the brunt of snow squall activity several times already this month. Meanwhile, snowpack east of Lake Huron has been noticeably reduced by the recent mild spell.

Outside of those regions, there really is not much snowpack left that can meaningfully contribute to a White Christmas. This includes Deep Southwestern Ontario, the Niagara Region, much of the Golden Horseshoe and into Eastern Ontario, including the Ottawa Valley.

estimated max temp on tuesday - MAP FROM WEATHERBELL

The first challenge arrives early this week as temperatures steadily rise above freezing for more than 24 hours. The warmest day looks to be Tuesday, with daytime highs climbing above freezing across much of Southern Ontario, with the main exception being parts of the Ottawa Valley.

Some areas could even push into the mid to upper single digits, especially in Deep Southwestern Ontario and around the Golden Horseshoe. That is more than enough warmth to put a serious dent in any remaining snow.

Rain may also enter the picture early Tuesday in some areas. Combined with above-freezing temperatures, this will further erode minor snowpack. At that point, the only snow that is truly expected to survive is east of Georgian Bay. For many other areas, including east of Lake Huron, the final outcome will depend heavily on the last 36 hours leading up to Christmas morning.

NEW SNOWFALL BY CHRISTMAS MORNING (cm) - MAP FROM WEATHERBELL

The system moving through on Tuesday is expected to bring light snowfall across Eastern Ontario. With temperatures expected to remain below freezing afterward, this snowfall should help lock in a White Christmas for the Ottawa area, even though there is currently very little snow on the ground. A general 5 to 10cm by Wednesday should be more than enough to tip the scales.

In Southwestern Ontario, however, the outlook is not as festive. Much of the snowfall associated with this system is expected to fall before temperatures rise and precipitation transitions to rain. Any snow that does fall will likely melt away quickly.

The one exception may be the higher elevations east of Lake Huron, where temperatures could hover near freezing just long enough for the snowpack to cling on until Christmas morning. Even there, it will be very close.

estimated temp on CHRISTMAS MORNING - MAP FROM WEATHERBELL

By Christmas morning itself, current indications suggest many across Southern Ontario will wake up to below freezing temperatures. That will help preserve whatever snow remains on the ground. This includes much of Central and Eastern Ontario, as well as higher elevations northwest of the GTA, such as Orangeville and Kitchener.

In Deep Southwestern Ontario and areas along the Lake Erie shoreline into parts of the GTA, temperatures are expected to be slightly above freezing. With very little existing snowpack to work with, those milder conditions are likely to melt away any lingering hope of a White Christmas.

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

Putting all of this together, we have created our preliminary White Christmas forecast. This is not the final word and adjustments are possible as we get closer to Christmas morning. Several of the uncertainties mentioned above will resolve themselves over the next couple of days, giving us a clearer picture than the models can provide right now.

Our highest confidence area, where we can almost guarantee a White Christmas with a 90 percent chance, covers a wide swath of Central Ontario, including Muskoka, Bancroft and northern and western Simcoe County. These regions have a deep, well-established snowpack. East of Lake Huron, we also assign a 90 percent chance for Hanover and much of Huron and Perth Counties, where repeated lake effect snow has buried the landscape.

Outside of that core region, we currently have a 75 percent chance for much of Eastern Ontario, along with areas such as Peterborough, Barrie and Kitchener. Confidence is fairly strong here, thanks to the existing snow southeast of Georgian Bay and the expected system snowfall in Eastern Ontario on Tuesday.

That said, melting remains a concern for Barrie and Kitchener if temperatures rise a bit more than expected on Tuesday. For Eastern Ontario, confidence also depends on the system delivering as forecast, so we want to see that snow on the ground before bumping probabilities any higher.

Closer to Lake Ontario, the dream of a winter wonderland starts to fade. From Kingston through the north GTA corridor and extending into London, we currently place the odds at around 50 percent. Along the immediate Lake Ontario shoreline, including much of the GTA, things become even more questionable with only about a 25 percent chance of a White Christmas.

For those in the Niagara Region and Deep Southwestern Ontario, including Windsor, Chatham and Sarnia, it may take a true Christmas miracle. Unless a last-minute snowmaker slides through just before Christmas morning, it looks like the Grinch may win this one.

We will continue to monitor the forecast closely and provide updates as Christmas morning draws nearer. Keep checking back, because in the weather, especially at Christmas, surprises are always possible.

Southern Ontario: School Bus Cancellations and Closures for Friday, December 19, 2025

**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

• Avon MaitIand Public & Huron-Perth CathoIic: There are several closures/cancellations, please visit this link for more details: https://hpsts.mybusplanner.ca/Alerts

• BIuewater Public & Bruce-Grey Catholic: All busses are cancelled.

• Dufferin-PeeI Catholic: Buses to St. Andrew, St. Peter, St. Benedict as well as ALL buses to Robert F. Hall CSS are cancelled today due to weather and road conditions.

• Kawartha Pine Ridge Public & Peterborough Victoria Northumberland Clarington Catholic: Bus and transportation service is cancelled to ALL schools in the STSCO jurisdiction for the day.

• Near North Public & Nipissing-Parry Sound CathoIic: Bussing for all weather corridors are cancelled today.

• Rainbow Public & Sudbury Catholic: All school related transportation services operating in the districts of SUDBURY, ESPANOLA, MASSEY AND MANITOULIN are cancelled today.

• Simcoe County Public & Simcoe Catholic: Busses are cancelled for Muskoka.

• Thames Valley Public & London CathoIic: Busses are cancelled today for Middlesex, Oxford, and Elgin Counties and Red Zone.

• Trillium Lakelands: All school vehicles to schools in all Zones for Trillium Lakelands District School Board have been cancelled.

• Upper Grand Public & Wellington CathoIic: All busses in Divisions 2, 3, and 4 are cancelled today.

French Schools

• Conseil catholique MonAvenir: Busses are cancelled for schools in Peterborough.

• Conseil scolaire catholique Providence: Busses are cancelled for Oxford, Middlesex, and Bruce-Grey.

• Conseil scolaire public du Grand Nord de l’Ontario (CSPGNO): All school related transportation services operating in the districts of SUDBURY, ESPANOLA, MASSEY AND MANITOULIN are cancelled today.

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

‘Snow Day’ Forecast: Icy Conditions Could Give Some Students an Early Start to Holiday Break Across Southern Ontario on Friday

For an updated list of school bus cancellations & school closures, please visit our live article: https://instantweatherinc.com/article/2025/12/19/bus-cancellations

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

A messy roller coaster of weather is expected across Southern Ontario throughout the day on Friday. It will begin with rain overnight, switching over to heavy snow right around the height of the morning commute. Temperatures will then plunge quickly, leading to the development of icy conditions.

To make things even more complicated, lake effect snow is expected to redevelop east of Lake Huron and Georgian Bay later in the day, with locally 10 to 20 cm of snow possible by Friday evening.

With the rain changing to snow, lining up with the morning commute and temperatures dropping through the freezing mark, there is potential for school bus cancellations, especially in rural areas.

The temperature drop is expected to be fairly gradual, which makes it uncertain whether Environment Canada will issue flash freeze warnings. That uncertainty also makes it harder to determine whether conditions will reach the threshold needed for widespread cancellations.

Our highest confidence lies in two regions that tend to be more sensitive to winter weather due to the large number of rural routes they serve. These include the North Hastings zone under Tri-Board Student Transportation Services and the Parry Sound and East Parry Sound regions within the Near North District School Board.

We have assigned these areas a 75 percent chance of bus cancellations. At this point, we are leaning toward cancellations, but not strongly enough to support a higher probability.

Across the broader rural portions of Central, Eastern and Southwestern Ontario, we have assigned a 50 percent chance of school bus cancellations, as conditions could easily go either way. We do expect several cancellations within this widespread zone.

This includes areas covered by the Avon Maitland District School Board, the Trillium Lakelands District School Board, North Bay under the Near North District School Board, Peterborough County within the Kawartha Pine Ridge District School Board, and much of Tri-Board Student Transportation Services. Kingston and Prince Edward County under Tri-Board sit lower at 25 percent. This zone also includes the Madawaska region within the Renfrew County District School Board.

Outside of these areas, there is still a slight chance of cancellations, although we are leaning toward buses running in most cases. As such, we have assigned a 25 percent chance to Lambton and Chatham-Kent within the Lambton Kent District School Board, Middlesex and Oxford counties under the Thames Valley District School Board, Dufferin and Wellington counties within the Upper Grand District School Board, the Simcoe West and Simcoe North weather zones, as well as the remaining portions of the Renfrew County District School Board and the Upper Canada District School Board.

For the rest of Southern Ontario, which is largely covered by more urban school boards, cancellations are unlikely. This includes Windsor under the Greater Essex County District School Board, London and Waterloo under the Thames Valley District School Board and Waterloo Region District School Board, the Greater Toronto Area including Toronto, Peel, York, Durham and Halton, the Simcoe Central and Simcoe South zones, and the Ottawa region.

Conditions in these areas are not expected to meet typical cancellation thresholds. Still, we have assigned a small 5 to 10 percent chance to account for the possibility of a few surprise decisions if icy conditions become more impactful than currently expected.

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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.

Southern Ontario: ‘Snow/Ice Day’ Forecast for Thursday, December 18, 2025

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

No major winter weather is expected across Southern Ontario on Thursday, and because of this, widespread school bus cancellations are unlikely.

That said, many areas have seen temperatures climb above freezing during the day on Wednesday, followed by an expected drop back below freezing later tonight and into early Thursday morning. This setup could allow for some localized icy conditions to develop, especially on rural roads.

Because of this possibility, we have assigned a widespread low to very low chance for an “ice day” across parts of Central and Eastern Ontario, as well as higher elevation areas of Southwestern Ontario.

We are not expecting cancellations, but if back roads become icy enough in a few localized spots, a surprise decision cannot be completely ruled out.

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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.

Southern Ontario: ‘Snow/Ice Day’ Forecast for Wednesday, December 17, 2025

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

Patchy freezing drizzle or light freezing rain is expected to develop across portions of Southwestern, Central and Eastern Ontario overnight Tuesday and into Wednesday morning.

While this freezing rain risk is not expected to be particularly impactful or widespread, it could still lead to a thin glaze of ice forming on untreated surfaces. This includes rural roads, sidewalks and vehicles, especially in areas where temperatures hover near the freezing mark through the night.

At this time, conditions are not expected to reach the threshold that would normally prompt widespread school bus cancellations. However, we cannot completely rule it out, especially if Environment Canada issues advisories overnight or if the freezing rain ends up being more widespread than currently forecast.

The most likely region to see an “ice day” is the North Hastings zone within Tri-Board Student Transportation Services. This area has a long history of being particularly cautious, largely due to its extensive network of rural routes where back road conditions can deteriorate quickly, even during relatively minor icing events. We have assigned this region a 25 percent chance to reflect that slightly elevated risk, though the overall lean remains toward buses running without major issues.

Elsewhere across the rural portions of Eastern, Central and Southwestern Ontario, we have assigned a low 5 to 10 percent chance of cancellations. Most school boards are expected to operate normally on Wednesday, but a few localized decisions cannot be ruled out depending on overnight road conditions.

This includes areas covered by Tri-Board, the Renfrew County District School Board, the Upper Canada District School Board, the Kawartha Pine Ridge District School Board, the Trillium Lakelands District School Board, the Near North District School Board, the Simcoe County District School Board, the northern portion of the Durham District School Board, the Upper Grand District School Board, the Bluewater District School Board and the Avon Maitland District School Board.

Outside of these regions, no weather-related school bus cancellations are expected on Wednesday. So for now, it looks like homework remains on the schedule.

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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.