Freezing Rain Threatens Icy Sunday Across Saskatchewan & Manitoba

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What previously looked like a possible widespread ice event, according to weather models, has luckily down-scaled and will now only impact a narrow track across parts of Saskatchewan and Manitoba.

A disorganized system will cross into Southeast Saskatchewan from Montana after midnight tonight, travelling northeastward and reaching Manitoba shortly before sunrise. This system will only bring a narrow band of precipitation to the region, but due to the presence of warm air aloft and below freezing temperatures at the surface, this precipitation will fall as freezing rain. The freezing rain will be light and last for several hours, resulting in ice accretion amounts up to 5mm.

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Temperature Profiles and Precipitation Types

By around the lunch hour, the freezing rain will start to taper off and transition over to snow. As the entire system pushes eastward, Southern Manitoba will also start to see some snow moving in from North Dakota Sunday afternoon. The system will become more organized throughout the evening and overnight, leading to the development of additional snow in Central and parts of Northern Manitoba. There is still some uncertainty regarding exact snowfall amounts, but it looks like the southern half of the province can expect 5-15cm of fresh snow by the end of Monday.

'Snow Day' Forecast: Extra Long Weekend for Some Students in Ontario as Squall Likely to Cancel Buses on Friday

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Intense snow squall activity is forecasted to bring a significant amount of snow to parts of the snowbelt region east of Lake Huron and Georgian Bay overnight and into Friday morning.

These squalls are expected to persist through the morning hours, creating hazardous conditions with near-zero visibility on the roads. Given these dangerous travel conditions, it is highly likely that many school boards will opt to cancel buses for Friday. For some areas, this would mark the second snow day in a row, as buses were already canceled on Thursday.

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The highest confidence for school bus cancellations remains in areas like Grey-Bruce, Avon Maitland (Goderich), Simcoe (North), Trillium (Muskoka), and Near North (Parry Sound). With active snow squall warnings in place and the potential for over 50 cm of snow to accumulate overnight, there’s little doubt that buses will be unable to operate safely in these regions. We’re assigning a 90% probability of cancellations in these zones.

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Outside the core snowbelt areas, the situation becomes less certain. For locations such as Listowel, Simcoe (West), and Trillium (Haliburton), we estimate a 75% chance of cancellations. While they are fairly likely, it’s not a guarantee. Regions including the rest of the Avon Maitland District School Board (AMDSB), Wellington, Dufferin, Simcoe (Central), Trillium (Kawartha), and East Parry Sound have a 50% chance of seeing cancellations, as snowfall in these areas is expected to be less intense or more variable.

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For the rest of Southern Ontario, school bus cancellations on Friday are unlikely since the snow squall activity will remain localized to the snowbelt. This means a sharp drop-off in probabilities as you move farther away from the areas most heavily affected.

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.

Widespread Temperatures Below -30°C and Windchills Approaching -45°C Have Prompted More Extreme Cold Warnings

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The extreme cold continues across Saskatchewan and Manitoba overnight tonight and through to tomorrow morning. Unfortunately, it will be colder than this morning, and a much larger area can expect temperatures below -30°C to settle in after midnight and continue until the late morning.

This intense cold poses a risk to everyone, especially young children, the elderly, individuals with chronic illnesses, outdoor workers, and those without adequate shelter. Symptoms of cold exposure, such as shortness of breath, chest pain, muscle pain and weakness, numbness, and colour change in fingers and toes, should be monitored closely.

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The winds are expected be light again, at around 10-15km/h, as the temperatures reach their lowest point. With the even colder air than this morning, these light winds are going to result in windchills that are approaching -45°C. The coldest windchills are expected in the Westman Region, but windchills below -40°C will still be felt over a significant area. As a result, Environment Canada has issued more widespread Extreme Cold Warnings than last night, stretching from Saskatoon and into Northern Ontario.

At these temperatures, frostbite can occur in as little as 30 minutes, and in some areas close to 10 minutes, so it is crucial to cover up when going out and limiting exposure all together. It’s also wise to keep emergency supplies in your vehicle, including extra blankets and jumper cables, in case of an emergency.

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'Snow Day' Forecast: Blizzard Conditions on Thursday Likely to Cancel Many School Buses in Southern Ontario’s Snowbelt

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Snow squalls are forecast to develop late Wednesday and persist into Thursday, bringing substantial snowfall to areas around Lake Huron and Georgian Bay.

Strong wind gusts are expected to accompany the intense snowfall, prompting Environment Canada to issue a rare blizzard warning for parts of Grey, Bruce, and Huron counties. Meanwhile, other regions are under a strongly worded snow squall warning, with predictions of snowfall accumulation potentially reaching up to 80 cm in localized areas.

Given the expected hazardous conditions, it’s highly unlikely that school buses will be able to operate safely in the affected areas on Thursday. As a result, it is anticipated that many school boards will opt to cancel school buses and might even decide to close schools entirely, particularly in regions under a blizzard warning.

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The highest likelihood of a ‘snow day’ applies to the entire Bluewater District School Board (BWDSB), Avon Maitland District School Board (AMDSB) - North Huron, Simcoe County District School Board (North and West weather zones), Trillium Lakelands District School Board (Muskoka region), and Near North District School Board (NNDSB - Parry Sound area).

These areas, which are under snow squall or blizzard warnings, have a greater than 90% chance of bus cancellations.

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Surrounding regions, including the remainder of Avon Maitland District School Board (southern zones), Simcoe County District School Board (Central and South weather zones), Student Transportation Services of Wellington Dufferin (STWDSTS), and Trillium Lakelands District School Board (Kawartha Lakes and Haliburton regions), have a 50–75% chance of snow day cancellations.

Although these areas are still under warnings, they are not expected to experience the most severe conditions. While bus cancellations are still likely, the confidence level isn’t as high as in the core impact zones.

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The probability of cancellations drops significantly outside the snowbelt, as the squalls are expected to remain highly localized. Eastern Ontario may be the only exception outside the snowbelt which has a low chance (10–25%) of cancellations.

While icy road conditions from an overnight freeze following earlier rainfall are possible, it is unlikely to be severe enough to prompt widespread cancellations. However, the possibility cannot be entirely ruled out.

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.

Return of Squalls to Ontario’s Snowbelt This Week With Blizzard Conditions & Over 50cm of Snow Possible

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While the brief break from lake-effect snow earlier this month brought milder air and rain to the snowbelt regions, the respite appears to be short-lived.

Snow squall activity is expected to make a comeback as we approach the end of the week. With multiple days of snow squalls anticipated, we could once again see impressive snowfall totals, rivaling those from earlier this month.

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Colder air will begin to filter into Southern Ontario from the northwest late Wednesday afternoon, dropping temperatures below freezing through the evening. This influx of cold air will trigger the development of lake-effect snow bands, with ideal conditions persisting through Thursday and into Friday.

Current projections suggest two primary zones will bear the brunt of the snow squalls: one east of Lake Huron and the other southeast of Georgian Bay. The Lake Huron squall is expected to impact southern portions of Grey and Bruce counties, including Owen Sound, Chatsworth, and Meaford. Meanwhile, the Georgian Bay squall will likely target central Simcoe County, extending northward into southern Muskoka.

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Snowfall totals in the hardest-hit areas could exceed 50 cm, with the possibility of approaching the staggering 100 cm seen in Bracebridge and Gravenhurst earlier this month. Whether such totals materialize depends on whether any of the snow squall bands remain stationary for extended periods.

To make matters worse, strong winds are expected to develop late Wednesday and persist into Thursday morning. Gusts could reach 60–80 km/h, particularly in Grey-Bruce and Simcoe County, significantly reducing visibility and creating hazardous travel conditions.

Blizzard conditions may develop, and travel is strongly discouraged during this timeframe. School bus cancellations are almost certain along the Lake Huron and Georgian Bay shorelines on Thursday.

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HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The lake-effect snow is expected to begin late Wednesday afternoon, with the first band forming off Lake Huron. Initially driven by northwesterly winds, this band will target areas near Goderich before shifting northward as winds veer to a more westerly direction by evening.

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HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By midnight, the main Lake Huron squall is expected to become stationary, affecting areas from Wiarton southward to Port Elgin, Owen Sound, and Meaford. Simultaneously, snow bands will begin forming off Georgian Bay, initially targeting Wasaga Beach, Midland, and Orillia. These may briefly lift northward Thursday morning, potentially reaching Gravenhurst and Bracebridge.

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HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The most intense conditions are forecast for late Thursday morning into the afternoon. Two main corridors of concern are expected: Owen Sound to Collingwood off Lake Huron, and Wasaga Beach to Orillia off Georgian Bay. Snowfall rates will be exceptionally high, and the squalls could remain locked in place for 6–12 hours, leading to rapid accumulation.

Strong wind gusts during this period could result in blizzard conditions, with near-zero visibility on roads. Road and highway closures are likely in the hardest-hit areas, especially on Thursday.

By late Thursday night, the snow squalls may shift into the Bruce Peninsula and Muskoka regions. While the bands are expected to weaken by Friday morning, lingering activity could still produce scattered flurries before tapering off completely by the afternoon.

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As with previous lake-effect events, it’s important to remember that these snow squalls are highly localized. Narrow bands of snow, often only a few kilometres wide, can result in dramatically different conditions over short distances. One location might see over 50 cm of snow while areas just a few kilometres away remain relatively unscathed.

We currently have high confidence in two zones being hardest hit: southern portions of the Bruce Peninsula, including Owen Sound, Chatsworth, Meaford, and Flesherton, and areas west of Orillia, including Midland and Coldwater. Accumulations in these regions could exceed 50 cm, with totals potentially nearing 100 cm if squalls remain stationary long enough. A more conservative estimate is 50–75 cm.

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A wider swath of Grey-Bruce, including Kincardine, Port Elgin, Hanover, Lion’s Head, and Tobermory, as well as much of Simcoe County and northern portions of Kawartha Lakes, Gravenhurst, and Beaverton, could see 25–50 cm. Not all areas in this zone will hit these totals, as much depends on the placement and movement of the snow bands.

Further south and away from the snowbelt, accumulation decreases rapidly. Barrie itself may largely miss the snow, although it could see up to 25 cm if the bands shift slightly. The Georgian Bay squall may extend inland at times, bringing heavy snow to Lindsay and Peterborough, with 10–20 cm possible in these areas.

For regions in other parts of the snowbelt, including Muskoka, Parry Sound, Haliburton, and parts of Dufferin, Wellington, Perth, and Huron counties, totals are expected to range from 10–20 cm. The Golden Horseshoe, including London, Kitchener, and Guelph, will likely see only light flurries, with less than 5 cm expected.

Extreme Cold Makes Its First Appearance of December With Windchills Dipping Below -40°C

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The extreme cold has returned to the Prairies with temperatures dipping below -20°C across a majority of Saskatchewan and Manitoba, with the exception of the Southwest Corner of Saskatchewan. Temperatures will be lower than -30°C in parts of Central Saskatchewan and into the Parkland Region of Manitoba. The cold Arctic air pushed south throughout the day today and temperatures will continue to fall overnight before reaching their lowest point in the mid-morning.

This intense cold poses a risk to everyone, especially young children, the elderly, individuals with chronic illnesses, outdoor workers, and those without adequate shelter. Symptoms of cold exposure, such as shortness of breath, chest pain, muscle pain and weakness, numbness, and colour change in fingers and toes, should be monitored closely.

Winds overnight tonight are expected be light, at around 10-15km/h. These light winds will easily push the windchill below -40°C, which has prompted Environment Canada to issue Extreme Cold Warnings for parts of both provinces.

At these temperatures, frostbite can occur in as little as 30 minutes so it is crucial to cover up when going out and limiting exposure all together. It’s also wise to keep emergency supplies in your vehicle, including extra blankets and jumper cables, in case of an emergency.

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Rapidly Strengthening Bomb Cyclone Expected to Bring Heavy Rain and Wicked Winds to the Maritimes

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Hang on to your umbrellas! We have an incoming bomb cyclone that is set to not only drench the Maritimes, but bring some intense winds to the region as well. A bomb cyclone is a storm that undergoes rapid intensification, called bombogenesis, that results in a drop in central pressure of at least 24mb over a 24 hour period. A system has begun travelling northward along the American Atlantic Coast and the further north it travels, the stronger it is expected to become under this rapid intensification.

The storm will bring precipitation to the Maritimes in two rounds. It will start off with warm, moisture-laden air being funnelled up from the Gulf along the warm front, leading to temperatures climbing into the double digits. Following a break in the precipitation from the first round, the length of which will be dependent on the distance from the centre of the storm, a second round of rain will move in along the cold front. Behind this cold front, temperatures are expected plummet and will fall below 0°C across New Brunswick, leading to the risk of a flash freeze. Combined, these two rounds of rain will bring a widespread 10-50mm of rain across most of the Maritimes.

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New Brunswick

Things in New Brunswick will certainly get messy over the coming days due to this incoming storm. The first wave of precipitation will move into Western New Brunswick around sunrise Wednesday morning. The temperatures will rise with the arrival of the warm front and rain, but there will still be some isolated pockets of cold air near the surface that could persist for several hours, leading to freezing rain. Luckily any ice accretion will quickly melt as temperatures rise.

The rain will continue throughout most of the day and it will start to taper off, from south to north beginning in the evening. Due to its proximity to the centre of the storm, there won’t be a break between to the rounds of precipitation in Northwest New Brunswick. As a result, this is where the highest rainfall amounts of close to 50mm are expected. The rest of the province will start to see this second wave move in from the west overnight. It will lose intensity as it pushes eastward and the heaviest rain will fall over the western half of the province, where 25-50mm of rain is expected overall with the storm and only 10-25mm to the east. This second round won’t last long and will exit the province by the late morning.

There will be a unique problem in New Brunswick that the rest of the Maritimes won’t have to worry about. Some parts of the province have a considerable snowpack over 30cm which will end up melting with temperatures rising into the double digits through the day Wednesday. However, when combined with the amount of incoming precipitation and the ground likely remaining at least partially frozen, standing water and flooding becomes a concern. To make matters worse, the temperatures will drop drastically across most of the province overnight Thursday, to well below the freezing mark, which could lead to a widespread flash freeze.

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Nova Scotia

The scenario across Nova Scotia with this storm will be a little less complicated, in regards to precipitation. The first wave of rain will make its way into Western Nova Scotia in the mid to late morning Wednesday. The rain will be heavy at times across the western half of the Mainland and it will then dissipate across the province through the evening. The second round of rain will then arrive early Thursday morning and is only expected to last 4 hours or so as it crosses the province, before the storm finally makes its way out of the region in the evening. Most of Mainland Nova Scotia and along the South Coast of Cape Breton Island can expect 10-25mm of rain while the rest of the province will see 5-10mm

Prince Edward Island

Prince Edward Island, much like Nova Scotia, has a fairly straightforward forecast with this storm. The first wave of rain will impact the Island starting early Wednesday afternoon and continuing into the evening. Then, the second wave will move in after sunrise on Thursday and cross the Island in the span of 3-4 hours. Rainfall amounts of 10-25mm are likely in Prince and the western half of Queens County and 5-10mm in Kings County and the eastern half of Queens County.

Strong winds will also be a factor with the incoming bomb cyclone. In this model image showing 1:00 AM Thursday, we can get a good look at both the size and structure of the storm, along with the precipitation types and their intensities. What we also see is the projected internal pressure of the storm, in millibars, as well as the lines of equal pressure, in black, known as isobars. Winds are driven by air moving from areas of high pressure to those of low pressure and when isobars are really close in strong storms, as seen in this case, we know that the winds will be quite strong.

The strong winds will start making their way into the Maritimes Wednesday evening and they will peak overnight. The entire region will get hit by sustained winds above 40km/h and gusts over 70km/h, but Western Nova Scotia and Southwest New Brunswick in particular will be hammered by gusts in excess of 100km/h. These will be onshore winds so pounding surf and some coastal flooding are very likely along the Atlantic Coast of Nova Scotia and along the Fundy Coast to the west of St. John starting late Wednesday and continuing through Thursday morning.

'Ice Day' Forecast: Widespread School Bus Cancellations Likely on Tuesday in Central and Eastern Ontario

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Following Monday's freezing rain that brought icy conditions across Central and Eastern Ontario, the risk of freezing drizzle persists through the overnight hours.

Environment Canada has issued widespread freezing drizzle advisories, warning that the slick conditions could extend into early Tuesday morning. With temperatures remaining near or just below the freezing mark overnight, untreated surfaces are expected to stay icy well into the morning.

As a result, it’s likely that many school boards, particularly in rural areas, will opt to cancel school bus services on Tuesday morning due to the hazardous road conditions.

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The highest confidence for cancellations is in rural Eastern Ontario, where freezing drizzle is expected to still be occurring at the time decisions are made. These areas have been given a 90% chance of an “ice day.”

In the City of Ottawa, the likelihood is slightly lower at 75%, as the school board tends to be more conservative with cancellations in urban settings. However, the overnight icing should still be significant enough to prompt cancellations.

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In Central Ontario, the Parry Sound and North Bay region has the highest probability of cancellations at 90%. The school board in this area is typically more weather-sensitive, and the lingering freezing drizzle almost guarantees that buses will be cancelled.

The situation becomes more uncertain for Muskoka, Haliburton, and Kawartha Lakes. Here, the freezing drizzle is expected to taper off shortly after midnight, but icy road conditions are likely to persist into the morning, with temperatures remaining near freezing.

After Monday’s decision to proceed with buses in some areas backfired for Trillium Lakelands—forcing adjustments to afternoon routes—the school board is likely to exercise more caution on Tuesday to avoid similar issues.

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South and west of these regions, the chances of cancellations decrease significantly. Freezing drizzle is expected to end earlier in the evening, and temperatures are forecast to rise overnight, mitigating icy conditions. While cancellations cannot be entirely ruled out—particularly in Simcoe County—most other areas are unlikely to see disruptions to bus services on Tuesday.

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.

'Ice Day' Forecast: Freezing Rain Threatens to Cancel School Buses on Monday in Parts of Southern Ontario

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Freezing rain is forecast to impact parts of Central and Eastern Ontario starting Monday morning and continuing throughout the day.

With Environment Canada issuing freezing rain warnings that highlight potential road hazards on Monday, it is highly likely that many school boards in the affected regions will choose to cancel bus services as a precaution.

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The highest likelihood of an “ice day” is focused on areas northwest of the GTA, particularly in higher elevations, as well as regions around Lake Simcoe and into Eastern Ontario north of the Lake Ontario shoreline.

For school boards in these areas, there is a 75% to 90% chance of bus cancellations. While confidence in cancellations is high, there remains a small possibility that some boards might take a gamble due to the later expected start of the freezing rain. This uncertainty has kept the chances from being universally set at 90%.

The only area where we feel a solid 90% confidence level is the southern portion of the Tri-Board district. Historically, this region has been very proactive in response to any Environment Canada winter weather warnings, so the presence of a freezing rain warning is likely enough to prompt cancellations there.

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Further north, including Muskoka, Haliburton, and the Ottawa Valley, messy weather may not arrive until later in the day. As of now, Environment Canada has not issued freezing rain warnings for these areas, which lowers the likelihood of bus cancellations.

Probabilities range from 25% to 50%, with just a 10% chance in the City of Ottawa. Urban cancellations in Ottawa typically require more severe conditions, so the lower chance is consistent with their past responses.

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In contrast, Southwestern Ontario and the GTA are expected to see mainly rain with minimal freezing rain, making school bus cancellations in these regions highly unlikely.

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.

Prolonged Freezing Rain Threatens Icy Start to Week for Parts of Southern Ontario on Monday

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December has kicked off with a cold and snowy start across Southern Ontario, as a significant lake-effect snow squall outbreak blanketed parts of the snowbelt over the past week. This wintry weather was accompanied by the season's first blast of Arctic air, bringing wind chills as low as -20°C.

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However, a shift in the weather pattern is underway, with milder conditions already spreading into Southwestern Ontario, where Sunday saw daytime highs climbing into the mid to upper single digits.

A weather system is expected to arrive early Monday, bringing warmer air aloft, while near-surface temperatures hover around freezing. This setup creates ideal conditions for freezing rain across parts of Central and Eastern Ontario, which, according to the latest data, could last for an extended period.

Freezing rain is expected to begin in the morning hours on Monday, persisting through the afternoon and into the evening. This prolonged event could result in a thin but hazardous layer of ice forming on untreated surfaces such as roads, sidewalks, trees, and power lines, with localized power outages a possibility.

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PRECIPITATION TYPE - MAP FROM WEATHERBELL

The initial bands of precipitation will move into Deep Southwestern Ontario, including Windsor and London, during the pre-dawn hours on Monday. Temperatures in this region will remain several degrees above freezing throughout the day, so precipitation here is expected to fall as rain.

As the system progresses north and east during the morning, it will encounter below-freezing temperatures near the surface in areas like the Dundalk Highlands (including Orangeville and Shelburne) and parts of the Greater Toronto Area (GTA).

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This will result in the development of freezing rain, creating a zone stretching from Orangeville eastward through York Region, along the higher elevations of the Oak Ridges Moraine, and into southern portions of Central and Eastern Ontario.

This band of freezing rain is expected to persist into the early afternoon, with locations such as Barrie, Orillia, Kawartha Lakes, Peterborough, and Belleville likely experiencing the heaviest impacts.

Further north, areas like Muskoka, Bancroft, and the Ottawa Valley are expected to see a mix of wet snow, ice pellets, and freezing rain beginning early Monday afternoon. While significant snowfall accumulation is not expected for Southern Ontario, enough snow could fall to create slushy and slippery road conditions in these areas.

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PRECIPITATION TYPE - MAP FROM WEATHERBELL

Freezing rain will begin to taper off in the south later in the afternoon, though freezing drizzle may linger into the early evening. Temperatures are forecast to rise slowly above freezing later in the evening and overnight, which should help melt any accumulated ice, albeit gradually.

In more northern portions of Central and Eastern Ontario, heavier freezing rain will persist into Monday evening before ending overnight. However, freezing drizzle may continue in the Ottawa Valley into early Tuesday morning, potentially causing icy conditions for the Tuesday morning commute.

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The most significant freezing rain impacts are expected in a narrow corridor extending around Lake Simcoe and eastward along the Lake Ontario shoreline.

Ice accretion of 2 to 5mm is possible in areas such as Orangeville, Newmarket, Collingwood, Barrie, Orillia, Midland, Bracebridge, Lindsay, Peterborough, Oshawa, Belleville, and Kingston.

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For the rest of Central and Eastern Ontario, including the Ottawa Valley, up to 2mm of ice accretion is expected, accompanied by ice pellets and a few centimeters of wet snow.

In the GTA, the greatest impacts from freezing rain will likely occur in the northern and eastern portions of the region. Toronto may experience brief freezing rain during the morning hours, but it is expected to transition quickly to rain, especially closer to the lakeshore.

The Second Storm of the Week Should Finally Bring Nova Scotia's First Decent Snowfall of the Season

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For the second time in a week, more snow is on the way for the Maritimes, with another short-lived Alberta Clipper moving in to finish the weekend. Nova Scotians can once again expect rain with this system, but that won’t happen until after some snow accumulates, making this the first decent amount of snow across most of the province this season.

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New Brunswick

The snow from the Clipper will arrive along the International border before sunrise Sunday morning and cross the province throughout the morning hours. The snow will be light to moderate, leading to a widespread 5-10cm across New Brunswick. Some light rain may mix with the snow along the Fundy Coast so snowfall totals could be limited here. Heavier snow is likely around Miramichi and into the Acadian Peninsula in the early afternoon, with snowfall rates reaching 2cm/hr and resulting in accumulations above 10cm in this area. By the early afternoon, the snow will start to taper off from west to east and ending in the evening.

Nova Scotia

The leading edge of the Clipper will push into Western Nova Scotia at around sunrise on Sunday. The western portions of the Annapolis Valley and South Shore will see this snow switch over to rain after only an hour or two, but as the system pushes further into the province through the morning, the snow will persist longer.

As we progress into the afternoon, the temperatures will rise to above freezing in mainland Nova Scotia, starting along the coasts and moving inland, causing the snow to transition to rain after only a few hours. As a result, snowfall totals will be higher, just above 5cm, in inland portions of the mainland and lesser along coastal areas. This snowfall won’t last and will quickly start to melt with the warmer temperatures and rain following it. The transition from rain to snow won’t occur until the evening in Cape Breton and the impacts of this will be limited overall. As usual, the higher elevations of the Highlands will remain cool, preventing a switch over to rain and resulting in snowfall accumulations above 10cm.

The system will start to make its way out of Nova Scotia starting in the late afternoon, with precipitation ending from west to east until finally exiting the province after midnight early Monday morning.

Prince Edward Island

The snow will reach Prince Edward Island around the lunch hour on Sunday and is expected to last throughout the afternoon before tapering off in the early evening. The snow is expected to be light, resulting in an almost province-wide 5-10cm of fresh accumulation with the exception of eastern King’s County, where temperatures will climb above 0° briefly in the evening and there will be a switch over to rain as the system finishes crossing the Island.

Fast Moving Clipper to Dump Up to 10-20cm of Snow on Parts of Ontario & Quebec This Weekend

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After a week dominated by seemingly endless snow squall activity across the snowbelt regions of Southern and Northern Ontario, the lake-effect snow machine is finally taking a break as we head into the first full weekend of December. However, this pause in squalls doesn’t mean the weather will be quiet for long!

We’re tracking a system originating from the Prairies that is expected to sweep across Ontario and Quebec between Saturday and Sunday. This fast-moving clipper will bring a widespread blast of snow, with accumulations ranging from 10 to 20 cm across Northern Ontario, Central and Eastern Ontario, and parts of Southern Quebec.

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Precipitation associated with this system has already begun moving into Northwestern Ontario from Manitoba and will continue spreading eastward through the overnight hours. Areas near the international border, including Fort Frances, may also see a risk of freezing rain. Light to moderate snow will develop around Lake Superior and into Northeastern Ontario by Saturday morning.

As Saturday progresses, the system’s first snow bands will push southward into parts of Southwestern, Central, and Eastern Ontario by the afternoon. Initially, snowfall is expected to be light but could reach areas within the Golden Horseshoe. A sharp cut-off in precipitation means Deep Southwestern Ontario and regions along the Lake Erie shoreline are likely to see little to no accumulation.

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By Saturday evening, the bulk of the precipitation will concentrate over Central and Eastern Ontario, where moderate to heavy snow will persist through the evening and into the early overnight hours.

Snowfall will taper off in Southwestern Ontario by the early evening and in the Greater Toronto Area by mid-evening. For the rest of Central and Eastern Ontario, snow will likely ease shortly after midnight, though areas closer to the Quebec border could see lingering snowfall into the pre-dawn hours.

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During this time, temperatures in Southern Ontario will gradually rise, pushing many locations above the freezing mark and resulting in a mix of rain and snow. Central and Eastern Ontario, however, are expected to remain cold enough to keep precipitation as all snow.

For Quebec, snowfall is forecasted to begin mid to late Saturday afternoon, with Montreal likely seeing its first snow bands just after dinner. Snow will continue through the overnight hours and is not expected to clear out until late Sunday morning.

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In terms of accumulation, this system is relatively straightforward compared to scenarios involving mixing or lake enhancement. Across Northern Ontario, a general 10 to 15 cm is expected, including areas such as Armstrong, Marathon, Wawa, Timmins, Chapleau, and Kirkland Lake. Isolated locations could see totals closer to 15 to 20 cm.

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Farther south, snowfall totals of 10 to 20 cm are anticipated across much of Central and Eastern Ontario and Southwestern Ontario east of Lake Huron. This includes regions such as Grey-Bruce, Orillia, Muskoka, North Bay, Sudbury, Peterborough, Kingston, and the Ottawa Valley. Similar accumulations are expected in Southern Quebec, including Montreal, where snowfall amounts of 10 to 15 cm are likely, with localized pockets nearing 20 cm.

Meanwhile, lower amounts are expected in areas such as London, Kitchener-Waterloo, the Niagara Region, and the western GTA, where snowfall totals will likely remain around 5 cm or less. Toronto, in particular, may see minimal accumulation due to limited moisture reaching the area as the system concentrates on Central and Eastern Ontario. Deep Southwestern Ontario will likely see only trace amounts.

Messy Weekend Clipper Expected to Bring Widespread 10-20cm of Snow and Risk of Freezing Rain to the Prairies

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It’s going to be a messy weekend across the Prairies with a Clipper expected to bring over 10cm of snow in a swath from Edmonton, through Saskatoon, to Winnipeg. This will be the first considerable snowfall of the season for the Winnipeg area, which has lagged behind the rest of the Prairie provinces by a couple of weeks.

The snow won’t be the only concern from this storm; there will be the risk of freezing rain across the region in pockets where temperatures will climb a degree or two above freezing. On top of the snow and freezing rain, some areas will also see rain from this storm, making for a mixed bag of a weekend!

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Alberta

Our Clipper will start to make its way into Alberta in the Northern Rockies as a disorganized mess of rain, snow, and mixed precipitation mid-morning Saturday. Temperatures are expected to climb above freezing across much of Southern and Central Alberta so as the system pushes eastward into the province through the afternoon, the precipitation should fall as rain.

Things become much more organized in the evening and as temperatures start to fall, most of the rain in Central Alberta will switch over to snow. There will be the risk of brief freezing rain during this transition which could make surfaces quite icy before being covered with snow. With the organization of the storm, snowfall rates will increase and snow accumulations above 10cm should start around Edmonton and continue east-southeastward along the track of the storm.

As the system starts to exit the province early Sunday morning, some precipitation will actually push into Southern Alberta. There will be brief freezing rain along the leading edge, bringing trace ice accretion to Red Deer and eastward, followed by some moderate snowfall that will lead to 5-10cm of snow to the area, including Medicine Hat. The snow will taper off in the west through Sunday morning, but it is expected to linger in the east through the day.

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Saskatchewan

The storm will extend into Saskatchewan starting in the late afternoon or early evening on Saturday. With the temperatures in the single digits, it will start off as a narrow band of rain. As the temperatures fall later in the evening, however, we expect there to be a transition over to freezing rain that will last for several hours as the storm continues its path southeastward. There could be a considerable track of ice accretion of 2-5mm that stretches from Saskatoon through Moosomin and into Southwest Manitoba.

Unfortunately, the freezing rain will eventually transition to snow from west to east overnight, which will cover the frozen ground, making things even more slippery. This snow will be moderate to heavy at times, with snowfall rates up to 2cm per hour, resulting in snowfall totals of 10-20cm over a wide stretch of the province.

During early morning hours of Sunday, snow will start to wrap around from the west, bringing 5-10cm of snow to Southwest and West Central Saskatchewan and lesser amounts along the International border. The snow will start to dissipate Sunday afternoon before ending Monday morning in the southeast corner of the province.

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Manitoba

In a similar fashion to what is expected in Saskatchewan, as the Clipper crosses into Manitoba overnight Saturday, the leading edge will bring freezing rain into the province. This is only expected in the southwest corner of the province and the greatest ice accretion of 2-5mm will be found in an area that includes Virden and Boissevain.

After a few hours of freezing rain, the snow will follow and spread eastward across Manitoba through the morning. The storm will grow in size as the snow wraps around from the west in the early morning and the arrival of heavier snow in the afternoon will lead to a wider area receiving 10-20cm. The storm will start to push into Northern Ontario early Sunday afternoon and the snow will start to taper off overnight before eventually exiting the region by early Monday afternoon.

Widespread wind gusts of 50-70km/h are expected with the Clipper so on top of surfaces being quite icy over a wide area, blowing snow will be a concern As a result, we may see some highway closures throughout the duration of the storm. Road conditions will likely be very poor in the hardest hit areas so please take extra caution when travelling this weekend!

'Snow Day' Forecast: Will London Area Students Ever Go to School? Likely Not Until Next Week!

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Intense snow squalls have developed off Lake Huron and Georgian Bay on Thursday, delivering significant snowfall to areas southeast of the lakes. This activity is expected to persist through the overnight hours, gradually weakening early Friday morning. However, snowfall totals in the hardest-hit regions are likely to exceed 50 cm by the time the squalls subside.

Given the expected heavy accumulation overnight, it is highly likely that some school boards in the affected regions will decide to keep buses off the roads for yet another day.

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The highest probability of cancellations will again be concentrated along the southeastern shoreline of Lake Huron. This includes the southern portion of the Avon Maitland District School Board (AMDSB) and the Thames Valley District School Board (TVDSB), which covers the City of London.

There is a 90% likelihood of bus cancellations in these areas, as the combination of the existing snowpack and additional overnight snowfall will almost certainly create treacherous travel conditions for the morning commute.

The remainder of the Lake Huron shoreline, including the northern section of the AMDSB, the entire Bluewater District School Board (BWDSB), and the “West” weather zone for the Simcoe County school board, has a 50–75% chance of cancellations.

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For school boards east of Georgian Bay, including the NNDSB (Parry Sound), Trillium Lakelands (Muskoka), and the “North” weather zone for Simcoe County, we have assigned a 50–75% chance of cancellations. Confidence here is slightly lower because the snow squalls in these areas are expected to intensify later in the day.

As mentioned in Environment Canada's snow squall watch, conditions will likely worsen in the afternoon, requiring school boards to make proactive decisions in the morning. This is particularly true for Parry Sound, where the school board has a history of erring on the side of caution when adverse weather is expected.

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Outside the snowbelt regions, the likelihood of a snow day is almost non-existent, as the heavy snow will remain highly localized to areas directly impacted by the squalls.

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.

London Area Could Get Hammered by Intense Snow Squall on Thursday With Locally Up to 50-75cm of Snow

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As the Alberta Clipper that brought widespread snowfall to Southern Ontario exits late Wednesday, snow squalls are set to return to the snowbelt regions. Unfortunately, the areas that were buried earlier this week will once again bear the brunt of this lake effect activity.

Locations just north and west of London appear to be in the bullseye, with the potential for 50 to 75 cm of fresh snowfall accumulation by the end of Thursday.

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Lake effect activity is expected to begin organizing overnight and into early Thursday morning along the southern shorelines of Lake Huron and Georgian Bay. Current forecasts suggest this activity will consolidate into a few well-defined snow squalls by late morning or early afternoon.

The most intense squall is projected to form off the southeastern shoreline of Lake Huron, extending from Port Franks through Strathroy and into the west end of London. Additional streamers could impact areas further inland and along the eastern Lake Huron shoreline, stretching from Kincardine down to Grand Bend.

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A separate squall will develop off Georgian Bay, spanning from Collingwood to Shelburne. Forecast models differ on the intensity of this squall, with some suggesting it could push far inland, potentially reaching parts of the Greater Toronto Area (GTA) just in time for the evening commute.

This scenario could bring a heavy burst of snow to the Hwy 400 corridor between Bradford and Vaughan, possibly extending to Mississauga and even the western parts of Toronto.

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The primary concern with this event is that the squalls are unlikely to shift much throughout the day. Instead, they could remain stationary for over 12 hours, beginning Thursday morning and continuing into the late evening.

As seen in Muskoka over the weekend, stationary squalls can produce extreme snowfall rates of 10–15 cm per hour, quickly overwhelming plowing operations and making travel nearly impossible as highways are buried in snow.

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Travel is strongly discouraged along the Lake Huron shoreline, particularly on Hwy 402 between London and Wyoming, during the day on Thursday and into the evening. Blizzard-like conditions, combined with rapid snowfall accumulation, will create dangerous and potentially life-threatening travel conditions.

The Georgian Bay squall is expected to diminish just after midnight, while the Lake Huron squall will gradually lift north of London during the pre-dawn hours on Friday. Additional lake effect snow is possible east of Lake Huron and Georgian Bay on Friday, though it remains unclear whether it will organize into significant squalls. We will provide updates in a separate forecast if substantial accumulation seems likely.

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The most intense snowfall is expected to target a small area west of London, including Parkhill, Ailsa Craig, and Strathroy, where totals could exceed 50 cm and potentially reach 75 cm. It’s important to note that these higher totals will be very localized, as the squall is forecast to be quite narrow. The exact location of the heaviest accumulation will depend on where the squall sets up.

While the City of London is likely to avoid the worst of the snowfall, it isn’t entirely in the clear. The city’s west end could see totals ranging from 25 to 50 cm. A slight eastward shift in the squall could place London directly in its path, significantly increasing snowfall totals for the area.

Lower amounts are expected in London’s east end, which is likely to see between 10 and 20 cm. St. Thomas could also be affected, with snowfall potentially reaching 20–30 cm depending on how far inland the squall extends.

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Other communities along the southeastern shoreline of Lake Huron, including Grand Bend, Lucan, Exeter, Clinton, and Goderich, are projected to receive 25–50 cm by the time the squalls diminish on Friday morning.

As is typical with snow squalls, snowfall gradients will be extremely sharp, and accumulation will drop off quickly outside the most affected areas. Locations such as Kincardine, Listowel, and Mitchell can expect totals of around 10–20 cm.

The Georgian Bay squall is anticipated to be less intense than its Lake Huron counterpart. Accumulations of 15–25 cm are expected for areas like Collingwood and Shelburne. If the squall extends into parts of the GTA, it could bring a quick 5–10 cm of snow, primarily affecting Brampton, Mississauga, and other areas in the western GTA.

Less than 5cm is expected for the rest of Southern Ontario.

'Snow Day' Forecast: Yet Another Chance of School Bus Cancellations on Thursday in Southwestern Ontario

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Snow continues to linger across Southern Ontario as of Wednesday evening, but it is expected to taper off as the system exits the province overnight. However, snow squalls are forecast to develop along the southeastern shorelines of Lake Huron and Georgian Bay, potentially creating hazardous travel conditions.

Environment Canada has issued widespread snow squall warnings, which could prompt some school boards to keep buses off the roads for yet another day.

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The highest probability of school bus cancellations is along the entire eastern shoreline of Lake Huron, including all regions within the Bluewater District School Board (BWDSB) and the Avon Maitland District School Board (AMDSB). This area is almost certain to experience a “snow day” on Thursday, with poor travel conditions making it difficult to see how buses could safely operate.

The Thames Valley District School Board (TVDSB), covering Middlesex, London, Oxford, and Elgin, also has a strong chance of cancellations, with probabilities ranging from 75% to 90%. The same applies to the Lambton zone of the Lambton Kent District School Board (LKDSB).

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Around Georgian Bay, there is a 75% chance of cancellations for the “West” weather zone of Simcoe County, where snow squall activity is expected to be most intense. The “Central” and “North” weather zones have a 50% chance, as it is less certain whether conditions will be severe enough to lead to cancellations.

To the east of Georgian Bay, the snow is expected to taper off overnight, offering a bit of a reprieve. However, the Parry Sound region still has a 50% chance of cancellations due to the potential for blowing snow, which could create hazardous conditions. This school board also tends to be particularly cautious when it comes to weather-related disruptions.

For the Muskoka region, there is a slight chance of cancellations. If schools do reopen, Thursday would mark the first day back for much of Southern Muskoka since last Thursday.

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For the rest of Southern Ontario, widespread cancellations are not anticipated. However, we have assigned a broad very low to low chance of cancellations across Eastern and Central Ontario, just in case blowing snow results in some unexpected disruptions.

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.

Mix of Wet and Wintry Weather on the Way for the Maritimes, Bringing More than 20cm of Snow to Parts of New Brunswick

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More snow is on its way for New Brunswick and in a similar fashion to last week’s storm, Nova Scotia can once again expect mostly rain with the possibility of a bit of snow mixed in. The incoming system will be a mix of an Alberta clipper coming through Ontario and a secondary low from New England, and it will be another short blast of winter for the region, with the entire event spanning 24 hours.

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Things will start off around midnight tonight as snow from the Clipper pushes its way into New Brunswick. As the snow spreads eastward across the province through the early morning hours, the low from the States will merge with the Clipper, which will funnel even more moisture northward from the Gulf. This secondary source of precipitation will reach Western Nova Scotia in the pre-dawn hours. The merging of these two systems will result in some intensification starting later in the morning, leading to heavier snow and rain across the region.

Nova Scotia

Nova Scotia will once again find itself in the warm sector of this storm, leading to precipitation falling mostly as rain for the duration of this event. However, there is a chance for some snow showers since temperatures will be hovering just above the freezing mark in some areas along the leading edge of the storm. Unfortunately for snow lovers, no real snow accumulation is expected from this storm, with temperatures climbing throughout the day and resulting in any snow transitioning to rain. The exception to this is, once again, in the higher elevations of Cape Breton where temperatures will remain below 0°C until Thursday evening, leading to 5-10cm of snow. Widespread rainfall totals across the rest of the province are expected to be in the 20-40mm range.

New Brunswick

On the other hand, New Brunswick can expect to need the shovels at some point on Thursday. The snow from the Clipper will push its way across the province throughout the early morning, but as the rain reaches Nova Scotia, it will also push into the Fundy Coast area, limiting snowfall accumulation along this stretch. Once the two systems merge and the storm intensifies, snowfall rates could approach 3cm per hour in the afternoon across Central and Northern New Brunswick, leading to widespread snow accumulations above 10cm. In the early and mid-afternoon, warm air will wrap around the backside of the storm, resulting in a transition from snow to rain that will push northeastward into the evening. Temperatures will fall overnight, but the warm air, along with the rain, will result in the melting of some of the fresh snow across most of the province.

Prince Edward Island

The leading edge of the precipitation will reach Prince Edward Island around noon on Thursday, with some light snow that will last for several hours. This will bring up to 5cm of snow across the Island before the warm air moves in and the snow switches over to rain. Similar to New Brunswick, the warm air and rain will melt most, if not all, of the freshly fallen snow across the province throughout the evening.

The storm will start to dissipate in the early afternoon, with the arrival of the warm air in New Brunswick and it will fully exit the region shortly midnight and into Friday morning. There could still be some lingering flurries or pockets of light rain throughout early Friday morning.

'Snow Day' Forecast: Heavy Snow on Wednesday May Cancel Some School Buses in Southern Ontario

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An Alberta Clipper is set to move into Southern Ontario early Wednesday, bringing the potential for 20-30 cm of snow in some areas. Snow squalls will also persist northeast of Georgian Bay, as well as near Lakes Erie and Ontario, during the morning hours.

The anticipated impact on Wednesday morning’s commute, combined with potential disruptions to the afternoon commute, will likely lead some school boards to cancel school buses. While there is still some uncertainty about how widespread these cancellations will be, certain areas have a higher probability of being affected.

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There is a 90% chance of a “snow day” for the Bruce Peninsula and areas northeast of Georgian Bay. This includes the entire Near North District School Board (NNDSB), which is known to be highly cautious regarding weather conditions. The expected snow squalls in these areas are likely to meet the criteria for bus cancellations.

For the rest of Central Ontario, parts of Eastern Ontario, and rural areas of Southwestern Ontario, the probability of school bus cancellations ranges from 50% to 75%. Confidence is slightly lower in these regions because much of the snow is expected to fall after morning cancellation decisions are made. Additionally, Environment Canada has gone with winter travel advisories, which may not carry enough weight for some school boards to cancel buses proactively.

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The likelihood of cancellations increases in areas forecasted to experience snow squalls or where blowing snow advisories are in effect. This includes regions along the shorelines of Lakes Huron, Ontario, and Erie, where reduced visibility and challenging travel conditions are expected.

In contrast, urban school boards in the Greater Toronto Area (GTA) are unlikely to cancel buses, as the forecasted conditions are not expected to meet the higher thresholds typically required for urban cancellations. We’ve assigned a slim 5-10% chance to account for the possibility of an unexpected decision by one of the boards, but this remains highly improbable.

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Similarly, Deep Southwestern Ontario—including Sarnia, Windsor, and Chatham—is unlikely to see school bus cancellations, as these areas are forecasted to receive less than 5 cm of snow from this system. Conditions there are not expected to be severe enough to warrant disruptions.

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.

Alberta Clipper to Bring a Snowy Blast to Southern Ontario on Wednesday With Up to 20cm Possible; Snowbelt Region Could See Up to 50cm

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The snowy landscape across Southern Ontario is quickly transforming as a multi-day snow squall event has blanketed parts of the snowbelt regions with over 100 cm of snow.

While the intense accumulation has primarily impacted areas around Lake Huron and Georgian Bay, the rest of Southern Ontario will soon have their turn as a weather system moves into the region on Wednesday.

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This system-related snowfall will likely combine with lake enhancement and embedded snow squalls, resulting in higher accumulations in the snowbelt areas that are still digging out from the weekend’s relentless snowfall.

By Thursday morning, some snowbelt regions could see an additional 30-50 cm of snow. Meanwhile, a general 5-15 cm of snow is expected across much of Southern Ontario, including parts of the Greater Toronto Area (GTA), which has experienced minimal snowfall so far this season.

The Alberta clipper responsible for this system began pushing into Northwestern Ontario from Manitoba on Tuesday afternoon. Moderate to heavy snow will continue spreading across Northern Ontario through the evening and overnight.

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In Northern Ontario, we expected the highest snowfall totals to be found east of Lake Superior stretching from Wawa down to Sault Ste. Marie. Snowfall totals of between 30 to 50cm are possible thanks to the system-related snowfall and snow squalls off Lake Superior.

Other areas around the Georgian Bay shoreline extending into Sudbury could be looking at around 20cm of snowfall accumulation. This will also be the case south of Lake Nipigon which could see some lake enhancement between Thunder Bay and Geardton.

The rest of Northeastern Ontario is looking at around 10 to 15cm with locally up to 20cm. Less than 10cm is expected for Northwestern Ontario including Thunder Bay.

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Ahead of the system, lake effect snow has already started to intensify, beginning with Lake Superior on Tuesday afternoon. By Tuesday evening, snow squalls are expected to organize off Lake Huron and Georgian Bay, primarily targeting the Bruce Peninsula and areas northeast of Georgian Bay, such as Parry Sound, Britt, and North Bay. These snow squalls are likely to persist through the night into Wednesday morning.

Additional lake effect snow could develop off Lake Erie and Lake Ontario during the early morning hours of Wednesday, potentially drifting into the southern Niagara region and Prince Edward County. While this activity may cause reduced visibility and locally heavy snowfall, the squalls are not expected to remain stationary for long, limiting overall accumulation.

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As the system reaches Southern Ontario around sunrise on Wednesday, the existing lake effect snow bands are expected to merge with the system’s light to moderate snowfall. This merging could enhance snow totals, particularly off the northern shorelines of Lake Erie and Lake Ontario. Narrow bands of heavy snow could stretch across the Niagara region and into parts of Central and Eastern Ontario, leading to significant variations in snowfall accumulations.

Snow totals will likely vary substantially due to localized banding caused by lake enhancement. Some areas may see only 5 cm, while nearby locations could receive 15-20 cm, depending on where the snow bands develop.

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Another key factor with this system will be strong wind gusts, ranging from 50-70 km/h across Southern Ontario, beginning Wednesday morning and continuing throughout the day. These winds, combined with steady snowfall, could create blowing snow and reduced visibility, making travel hazardous. With this being the first significant snowfall event of the season outside the snowbelt, drivers are urged to exercise caution.

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While the system is expected to exit Southern Ontario by late Wednesday, snow squall activity will persist off Lake Huron and Georgian Bay. An intense squall is projected to develop off Georgian Bay late Wednesday evening, stretching inland toward Midland, Orillia, and Gravenhurst, and continuing into the early hours of Thursday.

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By Thursday morning, shifting winds will push the Georgian Bay squall southward toward Collingwood and Angus. This squall may extend far inland at times, impacting the Highway 400 corridor between Vaughan and Barrie, as well as parts of the northern GTA. Meanwhile, a Lake Huron squall is anticipated to stretch from Goderich through Grand Bend and into the London area.

Significant snowfall could occur on Thursday if these squalls remain stationary for an extended period. Current models suggest they may not weaken until late Thursday night or early Friday morning, potentially producing intense snowfall rates for over 24 hours.

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Regarding snowfall totals, the uneven distribution caused by lake enhancement means localized accumulations will vary widely. The highest confidence lies in regions northeast of Georgian Bay, including Parry Sound, Sundridge, Britt, and North Bay, where 30-50 cm of snow is expected, with localized amounts possibly exceeding those totals due to snow squalls.

Surrounding areas, such as Muskoka and Orillia, could see 20-30 cm of snow by Thursday morning, accounting for system snow, lake enhancement, and snow squall activity. Similarly, areas east of Lake Huron could see totals ranging from 20-30 cm.

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In Central and Eastern Ontario, widespread snowfall is likely to range from 10-15 cm, except for the Ottawa Valley, where accumulations may be closer to 5 cm. Lake enhancement could push some areas along the northern shorelines of Lake Ontario and Prince Edward County closer to 20 cm.

For regions such as Kitchener, Woodstock, Guelph, and Barrie, snowfall totals are projected to reach 10-15 cm. However, variability due to lake enhancement may result in some areas seeing lower amounts. The GTA is expected to receive closer to 5 cm, while the Niagara region could accumulate 5-10 cm, with localized heavier bands of snow influenced by Lake Erie.

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In Deep Southwestern Ontario, snowfall amounts will decrease westward, with London forecasted to receive around 10 cm. Further southwest, including Sarnia, Windsor, and Chatham, totals are expected to remain under 5 cm.

It’s important to note that these totals do not account for the snow squalls expected to impact areas southeast of Lake Huron and Georgian Bay beginning Thursday morning. High-resolution models are still refining the locations of these squalls, but additional accumulations of 30-50 cm are possible in affected areas. Stay tuned for a detailed update in a separate forecast.

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Steep Drop in Temperatures Will Lead to Flash Freeze Risk This Evening and Freezing Rain Into Wednesday

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It’s been a bit of a weather roller coaster across Southern and Central Alberta over the past several days, with snow and frigid Arctic air late last week to single digit temperatures, melting snow and even some rain falling in the Northern Rockies.

Now, temperatures are expected to plummet later this evening, leading to a risk for a flash freeze along with freezing rain across a swath of the province continuing throughout the day tomorrow.

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Warm temperatures across Central and Southern Alberta in the single digits have resulted in the melting of some of the existing snowpack. On top of this, precipitation has already begun to push into the Northern Rockies region of Alberta from British Columbia as a mix of rain and snow this afternoon.

As the precipitation pushes deeper into the province and temperatures quickly fall to just below the freezing mark this evening, not only will the melted snow and slush rapidly freeze, the rain will also transition over to freezing rain, creating very icy conditions. This patch of freezing rain will remain fairly stationary around Grande Prairie into Wednesday morning, leading to ice accretions up to 5mm. At this point, the entire system will begin to push southeastward across the province, bringing light freezing rain along a narrow track throughout the day, adding to the already icy conditions expected from the flash freeze.

To the north of this freezing rain, where temperatures will be slightly cooler, light snow is expected to fall. Snowfall accumulations will also be limited with this system and a widespread 5-10cm is expected.