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

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

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

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

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

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

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

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

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

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

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

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

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

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

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

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

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

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

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

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

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

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

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

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

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

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

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

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

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

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

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

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

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

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

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

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

See below for our Lake Ontario and Lake Erie forecast.


PREVIOUS FORECAST:

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

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

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

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

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

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

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

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

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

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

Frosty Start Early This Week as Extreme Cold Brings Intense Snow Squalls in Parts of Southern Ontario

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Get ready for a blast of Arctic air across Southern Ontario this week! A surge of polar air will cause temperatures to plummet over the weekend and into early this week.

This extreme cold is also expected to trigger a multi-day snow squall event, which could result in significant snowfall for the usual snowbelt regions.

Dangerous wind chills approaching -30°C by Monday night, combined with intense snowfall rates, will create hazardous travel conditions. The hardest-hit areas are likely to be along the Lake Huron shoreline, including Grey, Bruce, and Huron counties.

Moderate wind gusts of 40-60 km/h could lead to blowing snow, with localized blizzard-like conditions possible. Non-essential travel in these regions should be avoided, as the extreme cold could quickly turn life-threatening if you become stranded.

While exact snowfall totals remain uncertain, the cold temperatures will enhance snowfall ratios, resulting in higher-than-usual snowfall rates for the same amount of moisture. Portions of Grey and Bruce counties along the shoreline could see snowfall accumulations exceeding 50 cm.

Lake Ontario and Lake Erie may also see localized lake-effect snow starting Sunday night and continuing through Tuesday. The Niagara region and Prince Edward County could receive 25-50 cm of snow in some areas, though accumulations will be highly localized.


TIMING

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The event will begin with light snow across Southwestern Ontario and the Golden Horseshoe on Monday evening. Lake enhancement along the Lake Huron shoreline and parts of the Western GTA and Northern Niagara region is expected.

However, it’s unclear how far these snow bands will extend inland, with some models suggesting they’ll remain close to the shoreline.

For example, high-resolution Canadian models show an intense but narrow squall near the Goderich region that doesn’t stretch far inland.

Similarly, a Lake Ontario squall may take an unusual path through Grimsby, St. Catharines, and Niagara-on-the-Lake, staying close to the shoreline.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Overnight Sunday into Monday morning, a more stable wind direction could allow a Lake Huron squall to push farther inland, potentially affecting Kitchener, Hamilton, and Burlington.

These areas could see a few hours of heavy snow during the morning commute.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By late Monday morning, the squall may gradually drift northward, reducing snowfall around Goderich as the wind shifts westerly. The Grey-Bruce region is likely to bear the brunt of the snow squalls at this point.

The Toronto area might see the edge of the squall by late morning, but snow intensity there remains uncertain.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

On Monday evening, a persistent squall is expected to form across the Bruce Peninsula and extend over Georgian Bay into Muskoka.

However, it may struggle to reach far inland, confining the heaviest snow to shoreline areas like Parry Sound, MacTier, and Bala. Bracebridge and Gravenhurst might avoid the worst of the snow—a welcome break after this winter’s relentless storms.

Lake Erie and Lake Ontario squalls will also intensify Monday night, with the Lake Erie squall drifting north into Port Colborne and Fort Erie.

Meanwhile, the Lake Ontario squall could impact southern Prince Edward County. Unfortunately, these squalls are unlikely to shift much overnight, meaning sustained snowfall and high winds could create treacherous conditions.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

As Tuesday morning approaches, the Lake Huron squall may refocus on southern Bruce County, including Owen Sound, Sauble Beach, Kincardine, and Hanover. These areas could face significant snowfall throughout the day.

The Lake Erie squall may drift southward, offering some relief to the Niagara region, though Fort Erie could remain under heavy snow. For Prince Edward County, the Lake Ontario squall may persist through much of Tuesday, delivering relentless snowfall.

A wind shift late Tuesday should end snow squalls off Lakes Erie and Ontario, but activity off Lake Huron may reposition toward the Bruce Peninsula and Muskoka.

Details for snow squall activity beyond Tuesday night will be covered in future updates.


THE BIG CHILL

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The big factor fueling these squalls is the frigid air moving over the relatively warm Great Lakes.

Temperatures could drop to -20°C by Monday night, with wind chills in the -30s for many parts of Southern Ontario, including the southwest.

This dangerous combination of extreme cold and heavy snow could lead to life-threatening conditions if you get stranded outdoors.

That’s why it’s critical to avoid travel during this period and stay home whenever possible.

School bus cancellations are likely on Monday and Tuesday due to both extreme cold and snow squalls.


HOW MUCH TO EXPECT

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As always with snow squalls, their narrow and shifting nature makes forecasting totals challenging. Some areas may see just 1 cm, while others a short distance away could be buried under 50 cm.

Model data suggests that Bruce County will be hardest hit, particularly along the Bruce Peninsula, Port Elgin, Kincardine, and Point Clark, where over 50 cm of snow is possible.

Huron and Grey counties, including Owen Sound, Chatsworth, Hanover, Wingham, and Goderich, could see up to 50 cm in places.

Inland areas like Kitchener and Orangeville may get up to 25 cm, while the Eastern Georgian Bay shoreline, including Muskoka, could see similar totals.

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The Niagara region, especially along its northern and southern edges, may get up to 25 cm of snow between Monday night and Tuesday. In Prince Edward County, localized totals of 50 cm are possible, especially in southern areas.

Kingston could see up to 10 cm, while eastern Ontario and deep southwestern Ontario will likely receive no more than 5 cm.

Stay tuned for updates as high-resolution models refine snowfall predictions.

For now, it’s clear that this storm will bring a mix of extreme cold, heavy snow, and treacherous travel conditions to Southern Ontario. Stay safe and stay prepared!

Arctic Blast Across Canada With Potentially Coldest Air in Years; Dangerous Wind Chills Near -40°C Possible Next Week

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Get ready for a major Arctic chill as some of the coldest air in over a year is set to spread across much of Canada over the next week.

This icy blast will originate in the Arctic and surge into Central and Eastern Canada, causing temperatures to plummet to dangerously low levels. Wind chills could drop to between -30°C and -40°C—or even lower—in several regions by early next week.

This extensive polar plunge will impact much of Canada and even stretch into parts of the United States. Over the next five to seven days, nearly everyone will feel the chill in some capacity.

The Prairies will be the first to experience this frigid air as it arrives late Friday into Saturday. By early next week, the cold will spread eastward into Ontario, Quebec, and Atlantic Canada, blanketing nearly all of the country in sub-zero temperatures. The cold snap is expected to last for a few days, but relief will arrive with more seasonal air by mid to late next week.


SATURDAY

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In Alberta, Saskatchewan, and Manitoba, the cold will start to settle in Friday night and intensify into Saturday morning. Temperatures will plunge below -20°C and could approach -30°C in some areas, even before factoring in the wind chill.

The coldest conditions will hit northern areas like Fort McMurray and Thompson, where wind chills could make it feel like -40°C to -45°C.

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Most of Saskatchewan and Manitoba, excluding Winnipeg, will see wind chills between -35°C and -40°C. Winnipeg and Edmonton will feel slightly less severe, with wind chills in the low to mid -30s, while Calgary will range from -25°C to -30°C.

Northern Ontario will also begin to feel the chill, with wind chills making it feel close to -30°C in places like Thunder Bay by Saturday morning.

Meanwhile, Southern Ontario will enjoy one last relatively mild day on Saturday, with temperatures near the freezing mark. However, the arrival of the Arctic air could bring a flash freeze late Saturday in Northeastern and Southern Ontario. Rapidly dropping temperatures may lead to icy road conditions, so caution is advised.


SUNDAY

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By Sunday morning, the cold air will deepen across the Prairies, bringing wind chills into the -40s for much of Saskatchewan and Manitoba. This includes locations like Edmonton, Fort McMurray, Saskatoon, Regina, and Thompson.

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Winnipeg and Calgary will be slightly less frigid, with wind chills closer to -30°C to -35°C, though colder temperatures are expected by Monday morning.

Ontario will also see temperatures drop sharply by Sunday morning. Northern Ontario will experience bitterly cold air, with actual temperatures between -20°C and -30°C and wind chills closer to -40°C in the northernmost areas.

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Southern Ontario will see temperatures ranging from -10°C to -20°C, with the coldest air in Central and Eastern Ontario. Wind chills in Northern sections of Southern Ontario could approach -30°C, while Southwestern Ontario and the Golden Horseshoe will feel like -20°C to -25°C.

The arrival of Arctic air could also reignite lake-effect snow squalls early next week. Snowbelt regions around Lake Superior, Lake Huron, and Georgian Bay could see heavy snowfall as a result. More details on this will be provided in a separate forecast.


STAYING SAFE IN THE EXTREME COLD

(Forecast continues below)

Extreme cold can pose significant risks to safety and health, especially when wind chill intensifies the freezing temperatures. Even moderate wind speeds can dramatically lower the "feels like" temperature, increasing the risk of frostbite.

When wind chill drops below -27°C, exposed skin can freeze in 30 minutes or less. At extreme levels, such as -40°C or colder, frostbite can occur in as little as 5-10 minutes.

To protect yourself and your loved ones, limit time spent outdoors during these dangerous conditions. If you must go outside, dress in multiple layers of loose-fitting, insulated clothing.

Make sure to cover all exposed skin with hats, scarves, gloves, and insulated boots. A windproof outer layer is essential to reduce the effects of cold winds.

Pay attention to frostbite warning signs, including numbness, tingling, or a loss of colour in fingers, toes, nose, or ears. If you suspect frostbite, immediately move to a warm location and avoid rubbing the affected area, as this can worsen tissue damage.

Hypothermia is another serious concern; symptoms include shivering, confusion, and slurred speech. Seek medical attention if hypothermia or frostbite is suspected.

For those driving during extreme cold, always keep an emergency kit in your vehicle with essentials such as blankets, extra clothing, food, and water.

Ensure your phone is fully charged, and let someone know your travel plans. Avoid leaving pets outdoors for extended periods, as they are equally susceptible to frostbite and hypothermia.


MONDAY

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The worst of the cold will likely occur Monday morning, especially in the west, with Arctic air entrenched across much of Central and Eastern Canada. Temperatures near or below -30°C will stretch from Alberta to Western Quebec.

Wind chills could make it feel like -40°C or colder across Saskatchewan, Manitoba, Northern Ontario, and parts of Eastern Alberta and Western Quebec. Calgary and Edmonton will escape the worst, but wind chills will still hover around -35°C.

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In Southern Ontario, most areas will see temperatures near -20°C, with Central and Southwestern Ontario experiencing the coldest air. Wind chills will make it feel like -25°C to -35°C, a pattern also expected in Montreal and Quebec City.

Atlantic Canada will begin to feel the polar plunge by Monday morning. Wind chills will drop to around -25°C in Northern New Brunswick, while Prince Edward Island and Nova Scotia will remain slightly milder, with wind chills ranging from -5°C to -15°C.


TUESDAY

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By Tuesday morning, the coldest air will shift further east, bringing some relief to the Prairies. Alberta will see temperatures climb back into the single digits, with wind chills in the teens.

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Eastern Saskatchewan will remain colder, with wind chills near -25°C to -30°C, while western regions warm slightly. Manitoba will also improve, though wind chills will still range from -30°C to -35°C, particularly near the Ontario border.

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Tuesday is likely to be the coldest day for Ontario, as the Arctic air peaks over the province. Northern Ontario will see temperatures between -30°C and -40°C, with wind chills plunging well into the -40s.

Southern Ontario will experience temperatures from -20°C to -30°C, with wind chills making it feel like -35°C to -40°C in Central Ontario and the Ottawa Valley, and -30°C to -35°C elsewhere.

Montreal and Quebec City will endure similarly bitter conditions, with wind chills of -35°C or lower. Central and Western Quebec will feel even colder, with wind chills dropping below -40°C.

Atlantic Canada will also face its coldest morning on Tuesday. Wind chills will range from -35°C in Northern New Brunswick to the -20s in Nova Scotia and Prince Edward Island.


WEDNESDAY

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Wednesday morning will bring one final bitterly cold start for much of Eastern Canada, but signs of improvement will begin to appear.

Southwestern Ontario, including Windsor, Sarnia, and London, could see wind chills near -35°C or even -40°C. Northern Ontario will finally climb above -30°C wind chills for the first time in days, marking the beginning of a warming trend.

Quebec will remain very cold, with wind chills near -40°C in some areas, while Montreal and Quebec City will continue to see wind chills of -35°C.

Atlantic Canada will face another cold morning, with wind chills between -20°C and -35°C.

Most of Eastern Canada will see a reprieve from the extreme cold by Thursday morning. However, this may only be temporary, as long-range models suggest another Arctic surge could arrive late next week into the weekend. Stay tuned for updates.

Intense Snow Squalls Return to Parts of Southern Ontario on Monday; Possible Deep Freeze for Late January

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⬇️ ZOOMED IN MAP CAN BE FOUND FURTHER DOWN ⬇️

The first half of January is almost behind us, and in Southern Ontario, the weather has shifted significantly compared to December. Colder temperatures have dominated, leading to several bouts of snow squall activity off Lake Huron and Georgian Bay. These events have primarily impacted regions southeast of the lakes.

The threat of snow squalls is set to return this week, with the heaviest snow expected east of Lake Huron and Georgian Bay. A predominant westerly flow will target areas such as Parry Sound, Bracebridge, Gravenhurst, and parts of Grey and Bruce counties. This pattern is reminiscent of what we experienced in early December, with heavy snow focused in the snowbelt regions east of Georgian Bay.

Snow squalls are forecasted to develop Monday afternoon and further intensify into the evening and overnight hours. Rapid snowfall accumulation and near-zero visibility are likely, especially late Monday into early Tuesday.

By the time the squall activity tapers off on Tuesday afternoon, some localized areas in the Muskoka and Parry Sound regions could see totals between 25 and 50 cm.

A brief reprieve from lake-effect snow is expected after Tuesday as milder air moves into Southern Ontario. However, another Arctic plunge is anticipated by early next week, potentially bringing some of the coldest air of the season.

Wind chills could make it feel like -30°C or even -40°C, especially in Central and Eastern Ontario!

This upcoming cold snap could also reignite intense lake-effect snow activity, with several rounds of squalls likely to impact the snowbelt regions throughout the rest of January.


BREAKING DOWN THE TIMING OF THE SQUALLS

Before the snow squalls begin Monday, a weak clipper system is forecasted to move across Southern Ontario late Sunday into early Monday morning. While this system will lack significant moisture, it may bring light snowfall of 2 to 5 cm in most areas, with localized pockets potentially reaching up to 5 cm.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

In the wake of the clipper, lake-effect snow is expected to ramp up east of Georgian Bay on Monday afternoon. Initially, the snow may be disorganized, spreading moderate to heavy snowfall across Muskoka and parts of Grey and Bruce counties.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By Monday evening, forecast models indicate the formation of a more organized snow squall. This band is expected to stretch from the Bruce Peninsula across Georgian Bay and inland between MacTier and Parry Sound.

The squall could remain stationary overnight, leading to rapid snowfall accumulation at rates of 5 to 10 cm per hour.

Model projections differ slightly regarding the exact placement of the most intense squall. The American model places the heaviest snow over Parry Sound, Pointe au Baril, Sprucedale, and Burk’s Falls.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Meanwhile, the Canadian model suggests the squall may shift south after midnight, targeting areas such as Port Carling, Rosseau, Port Sydney, and Bracebridge for the heaviest snowfall.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Both models agree that the squall will gradually sink southward by late Tuesday morning, bringing heavy snow to northern Simcoe County, including Midland and Orillia.

However, there is uncertainty about the intensity and duration of the squall as it moves further south into Barrie.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

While Georgian Bay will see the most intense squalls, Lake Huron is also expected to generate less intense snow bands Monday evening into Tuesday morning. These bands could impact Owen Sound, Kincardine, and Hanover, with bursts of heavy snow.

As the wind shifts southward, areas like Goderich and London may briefly experience lake-effect snow Tuesday morning into the afternoon.


WHO COULD GET BURIED IN SNOW

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As is typical with lake-effect snow, snowfall totals will vary widely depending on where the narrow bands persist. The highest accumulations are expected in Parry Sound, Rosseau, Port Carling, Port Sydney, Bracebridge, and Gravenhurst, where 25 to 50 cm of snow is possible by Tuesday afternoon.

In some areas, totals could exceed 50 cm if the squall remains stationary for an extended period.

Surrounding areas such as Midland, Washago, Coboconk, Minden, Huntsville, and Sprucedale may see snowfall totals of 15 to 25 cm.

The Grey-Bruce region, including Kincardine, Port Elgin, Wiarton, Lion’s Head, Tobermory, Owen Sound, Chatsworth, Hanover, and Meaford, is expected to receive 15 to 25 cm, with localized totals of 30 to 40 cm if squalls intensify.

Elsewhere in Central and Southwestern Ontario, snowfall amounts will range from 5 to 15 cm, combining accumulation from the weak clipper system and lake-effect snow. Most areas will see closer to 5 cm, with lake-effect zones reaching 10 to 15 cm.

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


SNOW SQUALL WATCH ISSUED BY ENVIRONMENT CANADA

CURRENT ENVIRONMENT CANADA ALERTS AS OF SUNDAY EVENING

Environment Canada has issued snow squall watches for areas around Lake Huron, Georgian Bay, and Lake Superior.

The highest totals in these watches match our forecast, with 20 to 40 cm expected for Parry Sound and Muskoka and 15 to 25 cm for the Grey-Bruce region.

Northern Ontario, including Sault Ste. Marie and Manitoulin Island could see localized snowfall of 10 to 20 cm from Monday evening into Tuesday morning.


LOOKING AHEAD TO THE REST OF JANUARY

The persistence of lake-effect snow this far into January may seem unusual, but the Great Lakes remain relatively ice-free and warmer than usual due to a mild fall and warm start to winter. This provides ample moisture for snow squalls when Arctic air moves in.

ICE COVERAGE MAP AS OF JANUARY 11, 2025 - source: NOAA

Colder weather in recent weeks has helped cool the lakes and increased ice coverage, particularly in shallower areas like Lake Erie and the shorelines of Lake Huron and Georgian Bay.

Ice coverage has risen from 1% at the start of January to over 10% as of January 11.

TEMPERATURE ANOMALY - MAP FROM WEATHERBELL

Looking ahead, a significant Arctic blast is expected during the January 20–24 period, with temperatures 10 to 20 degrees below seasonal norms across much of Southern Canada and the northern U.S.

Southern Ontario could experience lows well below -20°C, potentially nearing -30°C in some areas. Wind chills could make it feel as cold as -35°C to -40°C, particularly in Central and Eastern Ontario.

This intense cold will likely bring additional snow squalls and accelerate ice formation on the Great Lakes. If current trends continue, lake-effect snow activity could diminish significantly by the end of the month as ice coverage increases, shutting off the moisture source for squalls.

For snowbelt residents weary of lake-effect snow, relief may finally be on the horizon!

Widespread Snowfall to End the Week Across Southern Ontario on Friday; Up to 5-10cm Possible

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While 2025 began with heavy snow across parts of Southern Ontario, most of the activity so far has been confined to traditional snowbelt regions. That’s about to change, as a new system is set to bring the first widespread snowfall of the year to much of Southern Ontario starting Friday.

Most of Southwestern, Central, and Eastern Ontario can expect snowfall totals of 5 to 10 cm between Friday afternoon and Saturday morning. However, areas along the Lake Huron shoreline and into the Bruce Peninsula may see enhanced snowfall, with totals reaching 10 to 20 cm due to lake-effect activity and embedded snow squalls.

As the system moves out, additional snowfall is likely over the weekend. Lake-effect snow squalls developing southeast of Lake Huron and Georgian Bay could bring localized accumulations of 20 to 30 cm from Saturday afternoon into Sunday.


SNOWFALL TIMING

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The system-related snowfall will begin spreading into Southwestern Ontario late Friday afternoon, with regions near Lake Huron, including Deep Southwestern Ontario, seeing snow first.

Through the dinner hours, the snow will advance northeast, gradually reaching the Golden Horseshoe and portions of Central Ontario by Friday evening. By midnight, snow will cover most of Southern Ontario, extending into Eastern Ontario.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The most intense period of snowfall is expected overnight Friday into early Saturday morning. While the snow will generally be light, it could lead to several hours of steady accumulation, potentially impacting travel.

Exercise caution if you plan to drive during this time, and remember to adjust your speed to match road conditions.

For areas along the Lake Huron shoreline and into the Bruce Peninsula, lake-enhanced snowfall could intensify during the evening and overnight hours on Friday, resulting in heavier accumulations compared to surrounding areas.

Snowfall from this system will taper off from west to east starting early Saturday morning in Southwestern Ontario, with Eastern Ontario holding onto snow until late morning.

Flurries may linger into Saturday afternoon, especially in some regions.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

As the system exits, lake-effect snow squalls may develop off Lake Huron and Georgian Bay by Saturday afternoon. Forecast models currently show some uncertainty about how organized these squalls will be and whether they will lock into specific areas for prolonged periods.

Higher-resolution models are just coming into range, so a detailed forecast for snow squall activity will be issued on Friday.


HOW MUCH SNOW TO EXPECT

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In terms of totals, most of Southern Ontario will see 4 to 8 cm of snowfall, with slightly higher amounts of up to 10 cm possible in localized areas. This includes the east end of the Greater Toronto Area (GTA), such as Oshawa, and parts of Southwestern Ontario due to minor lake enhancement from Lake Ontario and Lake Huron.

The Golden Horseshoe and Ottawa Valley are expected to see slightly lower snowfall amounts, closer to 3 to 6 cm.

A zone along the Lake Huron shoreline—including Grand Bend, Goderich, Kincardine, and the Bruce Peninsula—could see locally higher accumulations by Sunday afternoon. Current estimates suggest 10 to 15 cm for these areas, with up to 20 cm possible for the Bruce Peninsula.


WEEKEND SNOW SQUALL PREVIEW

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Environment Canada has identified areas near Barrie, Goderich, and London as hotspots for the most intense snow squalls over the weekend.

Here’s Environment Canada’s weekend outlook:


Saturday, January 11, 2025: “Lake effect snow squalls off Lake Huron and Georgian Bay are expected to develop Saturday afternoon. Local snowfall amounts of 10 to 15 cm are possible along with reduced visibility in heavy snow.”
Sunday, January 12, 2025: “Lake effect snow squalls off Lake Huron and Georgian Bay are expected to continue on Sunday. Local snowfall amounts of 10 to 15 cm are possible along with reduced visibility in heavy snow.”

As always, stay tuned for updates, especially if you’re in areas likely to experience lake-effect snow. Stay safe, and plan ahead for winter driving conditions!

Retrograding Storm Returns to the Maritimes, Bringing Up to an Additional 30cm of Snow

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It seems as though the storm from the weekend isn’t quite finished with the Maritimes. There have been scattered flurries across the region throughout the day Tuesday, but more organized bands of snow are on their way.

 

The snow will move into Northern New Brunswick from the north early Wednesday morning and spread southward into the region. By sunrise, the snow will reach Prince County, PEI and then Northern Nova Scotia by the early afternoon. This band of snow will last for up to 12 hours, but the snow will be light and come in bursts, resulting in up to 5cm of accumulation.

 

In the late afternoon and early evening, a second band of snow will push southward into Northern New Brunswick and following the same path as the first. This round will bring another 12 hours of steady snow across the region before starting to dissipate early Thursday morning. There will be pockets of heavier snow in this second wave, which will drive snowfall totals above 10cm in some parts of the Maritimes.

 

The snow will taper off throughout Thursday morning, but in the late morning to early afternoon, one final round of precipitation will move in. This third and final round will arrive after temperatures climb above freezing, resulting in mostly rain falling, but a bit of snow mixed in, across the Maritimes Thursday afternoon and into early Friday morning.

 

From these three rounds of precipitation, we’re looking at widespread snowfall totals of 5-20cm across the Maritimes. There will be areas where the snow will persist into late Thursday morning from the second round of snow, particularly the Annapolis Valley and at higher elevations in Northern New Brunswick. There will also be areas where more snow than rain will fall in the third round, namely the Northumerland Shore and the Cape Breton Highlands. The Highlands will see the most snow, up to 30cm, due to steady and often heavy snowfall over the duration of this event.

Mid-Week Squalls Could Dump Up to 25-50cm of Snow to Parts of Southwestern Ontario by Thursday

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The New Year has certainly started on a frigid note across Ontario, as Arctic air has firmly settled over the region in recent days. These cold temperatures, combined with open lakes, have created the perfect conditions for lake-effect snow. Late last week and into the weekend, parts of the province experienced significant snowfall, with totals southeast of Georgian Bay reaching or exceeding 50 cm.

Over the past 24 hours, the lake-effect machine has largely taken a break, aside from some minor activity south of Lake Huron and Georgian Bay. However, that respite will be short-lived. Beginning Tuesday evening, snow squalls are expected to return with a vengeance as wind directions realign and even colder air moves into the region. These squalls are anticipated to persist through Wednesday and into early Thursday before tapering off.

This round of lake-effect snow will likely target areas that were largely spared during the last event. The focus this time will be on regions southeast of Lake Huron and along the southern shoreline of Georgian Bay. Some of the hardest-hit areas could include London and Collingwood, with snowfall totals potentially ranging from 25 to 50 cm over the next 48 hours.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

As for the timing, models differ slightly on the intensity and precise placement of the squalls. The latest data suggests snow squalls could begin organizing as early as Tuesday evening. The squall off Georgian Bay is expected to impact the Collingwood and Blue Mountain area, stretching inland toward Creemore, Alliston, and Shelburne. It may also affect the Highway 400 corridor just south of Barrie.

Meanwhile, activity off Lake Huron could produce multiple squalls developing between Kincardine and Grand Bend, with bands extending inland in a southeasterly direction. This puts portions of Huron, Perth, and Middlesex counties in the crosshairs.

The Georgian Bay squall appears to be somewhat weaker than its Lake Huron counterpart, likely due to the smaller lake surface area supplying moisture. That said, it is expected to remain relatively stationary through the overnight hours into Wednesday, resulting in steady snowfall accumulation and reduced visibility.

Travel in this area will likely be challenging from Tuesday night into Wednesday, with little improvement expected until the activity begins to subside overnight.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Lake Huron squalls, on the other hand, are expected to shift around more frequently, spreading out snowfall accumulations. By Wednesday morning, the primary squall is forecasted to come ashore around Grand Bend, extending inland toward Lucan, Strathroy, and London.

There is still some uncertainty about whether the squall will directly impact the City of London or remain just northwest. Western parts of the city are likely to see the heaviest snowfall, while eastern areas may receive lighter accumulations.

Scattered snow squalls east of Lake Huron are expected to continue affecting Huron and Perth counties throughout Wednesday. These squalls may vary in intensity, and if one becomes particularly organized and stalls over an area, rapid snowfall accumulation could occur.

The most intense conditions are expected during the day on Wednesday, extending into the evening and overnight hours.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By midnight, the lake-effect activity is expected to become more localized. The Georgian Bay squall will likely retreat closer to the shoreline, while the Lake Huron squalls may consolidate into a narrower band near Grand Bend, extending into the London area.

While this will reduce the overall impact, areas caught under these more focused squalls could experience increased snowfall rates for several hours overnight into early Thursday morning.

By pre-dawn Thursday, the lake-effect activity is anticipated to taper off, with the Georgian Bay squall dissipating before sunrise and the Lake Huron squall following a few hours later.

Snowfall totals from this round of snow squalls will vary widely, as is typical with these events. This forecast is particularly tricky due to discrepancies in model data regarding the intensity of the snow bands, which will significantly affect accumulation.

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Based on the current environment and dynamics, there is potential for 25 to 50 cm of snow in areas such as London, Lucan, Grand Bend, Clinton, and Collingwood. However, these totals are not guaranteed, as exact amounts will depend on where the bands set up.

For London, in particular, snowfall accumulations will likely be heavier in the northwest, while eastern areas may only see totals between 10 and 25 cm.

Surrounding areas like Goderich, Point Clark, Mitchell, Strathroy, and St. Thomas could see localized accumulations of 15 to 25 cm, depending on the positioning of the bands. Similarly, areas southwest of Barrie, including Angus, Alliston, and Beeton, may receive 10 to 20 cm as the Georgian Bay squall extends inland.

Outside these regions, significant snowfall is not expected due to the highly localized nature of lake-effect activity. However, portions of Eastern Ontario near the U.S. border and areas east of Ottawa may see 5 to 10 cm of accumulation on Wednesday due to a separate system lingering over Quebec.

First Major Winter Storm of the Year is Taking Aim at Cape Breton Island With Over 50cm of Snow Possible

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The new year is starting off with a bang in parts of the Maritimes with the arrival of a major winter storm. While Newfoundland will feel the brunt of the storm, Eastern Nova Scotia and Prince Edward Island can expect a significant amount of snow and strong winds throughout the day Sunday and into Monday. The rest of the Maritimes, meanwhile, will experience little to no impacts from the storm.



The storm has been rapidly intensifying during its approach towards Atlantic Canada throughout the day Saturday, meeting the criteria of a bomb cyclone (a drop in internal pressure of at least 24mb in 24 hours).

The western edge of the storm will briefly skim along the far eastern coast of Cape Breton Island early Sunday morning as the storm surges north towards Newfoundland, bringing snow and wind gusts of 70-90km/h. The storm will continue to grow in size as it gains latitude, which will push the snowfall and intense winds deeper into Cape Breton as the morning progresses.



By the mid-morning, the storm is expected to shift and start moving along a more northwesterly track, which will bring the snow and strong winds into Eastern Mainland Nova Scotia, across Prince Edward Island, and briefly to the eastern tip of the Acadian Peninsula. Blowing snow will greatly reduce visibility across the area throughout the day and could even lead to blizzard conditions.

The storm will gradually lose momentum later in the afternoon before completely stalling for several hours in the late evening and overnight. This will result in the impacted areas of PEI and Nova Scotia seeing snow quickly accumulate and the strong winds continuing while also limiting how far westward into the rest of the Maritimes that the snow spreads.

Model run showing Snow (Blue) and Rain (green) at 11pM on Sunday, January 5th



At around sunrise on Monday morning, the storm will start to fall apart, with the snow tapering off and the winds dying down across PEI and Mainland Nova Scotia throughout the morning. By the early afternoon, the only snow falling will be in the Cape Breton Highlands, where it will continue until the late evening.

The Cape Breton Highlands will be the hardest hit area and heavy snow is expected to fall for 24 hours at up to 5cm/hr, leading to over 50cm of accumulation here. This area will also see the strongest wind gusts from the storm, up to 100km/h, making travel very treacherous and possibly resulting in power outages.

Snow Squall Blast Continues This Weekend as Parts of Southern Ontario Could See an Additional 25-50cm of Snow

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The New Year has certainly started on a snowy note for parts of Ontario's snowbelt regions. A multi-day snow squall event is underway around Lake Huron and Georgian Bay, with some areas already receiving over 50 cm of snow. Locations east of Lake Huron, Simcoe County, and parts of Kawartha Lakes have been among the hardest hit so far. While the activity off Georgian Bay weakened somewhat on Friday evening, it's expected to ramp up again by Saturday afternoon and continue through Sunday. Snow squalls will also persist east of Lake Huron Friday night into Sunday, though the bands will shift around multiple times during this period. By the end of the weekend, some areas could see an additional 25 to 50 cm of snow, with localized totals reaching as high as 75 cm. Combined with the snow that has already fallen, totals in the hardest-hit regions could exceed one meter (100 cm). This includes parts of Simcoe County, where 50 to 75 cm of snow has already accumulated over the past two days. As of Friday evening, multiple discrete squalls off Lake Huron are bringing heavy snow to areas stretching from Bayfield to Kincardine and as far inland as Woodstock, Kitchener, and Guelph. This activity is expected to continue through the night, with southern squalls gradually merging northward by early Saturday morning.

The New Year has certainly started on a snowy note for parts of Ontario's snowbelt regions. A multi-day snow squall event is underway around Lake Huron and Georgian Bay, with some areas already receiving over 50 cm of snow. Locations east of Lake Huron, Simcoe County, and parts of Kawartha Lakes have been among the hardest hit so far.

While the activity off Georgian Bay weakened somewhat on Friday evening, it's expected to ramp up again by Saturday afternoon and continue through Sunday. Snow squalls will also persist east of Lake Huron Friday night into Sunday, though the bands will shift around multiple times during this period.

By the end of the weekend, some areas could see an additional 25 to 50 cm of snow, with localized totals reaching as high as 75 cm. Combined with the snow that has already fallen, totals in the hardest-hit regions could exceed one meter (100 cm). This includes parts of Simcoe County, where 50 to 75 cm of snow has already accumulated over the past two days.

As of Friday evening, multiple discrete squalls off Lake Huron are bringing heavy snow to areas stretching from Bayfield to Kincardine and as far inland as Woodstock, Kitchener, and Guelph. This activity is expected to continue through the night, with southern squalls gradually merging northward by early Saturday morning.


HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By Saturday morning, an intense squall is expected to form between Sauble Beach and Kincardine, extending inland to areas such as Hanover, Dundalk, and Orangeville. This band may stretch as far east as the western GTA, including Mississauga and Brampton.

While overall accumulations in the GTA should remain around 5 cm or less, these squalls could still lead to near-zero visibility and hazardous travel conditions due to blowing snow.


HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

For Georgian Bay, lingering lake-effect activity will continue Friday night into Saturday morning, though no significant squalls are expected until later in the day.

By mid to late Saturday afternoon, the Lake Huron squall is expected to shift northward as wind directions change. This will allow it to cross over the southern Bruce Peninsula and connect with Georgian Bay, bringing heavy snowfall to Simcoe County, particularly in the Barrie-Orillia corridor.

This squall may also extend into parts of northern York and Durham regions, as well as the Kawartha Lakes region.

As seen earlier in this event, the squall is expected to lock in place, leading to intense snowfall rates of 5 to 10 cm per hour late Saturday through Sunday. Driving conditions will deteriorate rapidly, and non-essential travel should be avoided due to the potential for road and highway closures.

By late Sunday morning, the Georgian Bay squall is expected to sink southward, bringing an end to the snow for areas southeast of the bay. Moderate to heavy lake-effect snow may persist in parts of Grey and Bruce counties throughout Sunday, with activity finally tapering off overnight into Monday morning.


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The heaviest snowfall totals are expected in areas such as Wiarton, Owen Sound, Kincardine, Hanover, Meaford, Collingwood, Wasaga Beach, Midland, Barrie, Orillia, and Beaverton. These regions could see an additional 25 to 50 cm of snow by the end of the weekend, depending on the squall locations.

Surrounding areas, including Goderich, Woodstock, Stratford, Kitchener, Guelph, Angus, Bradford, Lindsay, and Port Perry, may also see significant snowfall if the squalls align. These areas could receive 15 to 25 cm of snow, though amounts will vary widely due to the localized nature of snow squalls. Our forecast is intentionally broad to account for potential shifts in squall placement.

Snowfall amounts will drop off quickly outside the snowbelt regions. However, parts of the northern and western GTA could see 5 to 10 cm, with isolated amounts up to 15 cm. Even Toronto might get a few centimeters of brief, heavy snow as the bands shift inland.

Eastern and Deep Southwestern Ontario are not expected to see any significant snowfall from this event.

A Brief Skiff of Snow Expected Across Parts of Southern Alberta & Saskatchewan for the First Weekend of the New Year

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It’s been fairly quiet across the Prairies for the past few weeks and that trend has continued so far in the beginning of the new year. As we approach the first weekend of the year, there’s enough snow expected for parts of Southern Alberta and Saskatchewan over the next 24 hours to warrant a forecast.



The snow will begin to fall along the American border in Alberta early this evening and it will gradually spread north and eastward overnight and early Saturday morning. It is only going to reach as far north as Calgary and into Southwest Saskatchewan before the system starts to fall apart before sunrise Saturday morning. The snow will gradually taper off throughout the morning and into the early afternoon.

The snow is expected to be light throughout the duration of the event, leading to most of the area receiving 5-10cm of accumulation. As the system falls apart Saturday morning, the snow is expected to linger over parts of Southeast Alberta and Southwest Saskatchewan, resulting in over 10cm of snowfall here.

Snowy Start to 2025 in Ontario’s Snowbelt; Squalls Could Deliver Up to 50cm of Snow by End of Week

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As we kick off the New Year across Ontario, we’re starting off with a blast of cold Arctic air that moved into the region over the past 24 hours. With this chilly air comes the inevitable return of lake-effect snow in the traditional snowbelt areas surrounding Lake Huron, Georgian Bay, and Lake Superior.



Strong snow squalls are anticipated to develop Wednesday evening and are likely to persist through Thursday and into Friday. These squalls are expected to bring intense snowfall rates of 5-10 cm per hour, along with near-zero visibility that will make travel nearly impossible in the hardest-hit areas.

The main focus for this lake effect activity will be in parts of Huron, Perth, Grey, Bruce, and Simcoe counties. Depending on where these narrow snow bands establish, localized accumulations could approach or exceed 50 cm by week’s end, with additional snowfall possible through the weekend as the lake effect machine remains active.



HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Disorganized squalls are expected to begin forming off Lake Huron and Georgian Bay late Wednesday evening or around midnight. According to the latest data, multiple bands could develop off Lake Huron, with one possibly targeting areas south of Owen Sound.

Another band may stretch from Goderich inland towards Stratford and St. Marys, just north of London. However, there remains some uncertainty about where exactly these squalls will set up, which will determine the heaviest snowfall locations.



For Georgian Bay, models show differing timelines. One suggests squall activity could begin just after midnight, while another predicts development near sunrise on Thursday. If squalls form, areas like Wasaga Beach and Barrie could be affected overnight.

Overnight, the bands that do form may shift around and dissipate periodically, spreading snowfall over a broader area. If a squall locks into place unexpectedly, snowfall can accumulate rapidly in a short time.



HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The event is expected to intensify by mid to late Thursday morning as the northern squall off Lake Huron drifts northward, potentially crossing the Bruce Peninsula and reconnecting over Georgian Bay. This setup could lead to a rare "multi-lake connection," allowing the squall to draw moisture from a long stretch of open water.

The result would be heavy snowfall affecting areas such as Owen Sound, Collingwood, Wasaga Beach, and Barrie, with possible extensions into Durham Region and southern Kawartha Lakes.

Another squall off Lake Huron could extend inland into Huron and Perth counties, with potential impacts as far as Kitchener-Waterloo. While intense snowfall could occur, squalls are notoriously narrow, and not all areas will be directly affected.



HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By late Thursday afternoon, snow squalls off Lake Huron may weaken as the wind shifts more westerly, reducing the available lake surface from which the squalls can pull moisture. The Georgian Bay squall, however, could continue intensifying and shift northward, potentially impacting areas like Midland and Orillia while giving Barrie a break.

There remains uncertainty regarding the squall's position, with some models suggesting it may remain south of Orillia. If the squall locks in place overnight, areas such as Simcoe County and southern Kawartha Lakes could see prolonged periods of heavy snow, leading to extremely poor travel conditions, potential road closures, and significant snowfall accumulations.

By late Friday morning, shifting winds are expected to push the Georgian Bay squall southward, potentially dissipating it by midday. However, lake effect activity off Lake Huron may persist southeast of the lake into areas like Kitchener and London through Friday afternoon and evening.



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The hardest-hit regions from this event will likely include Grey-Bruce and southern and central Simcoe County, including Wasaga Beach and Barrie. Snowfall totals in these areas could range from 25 to 50 cm by Friday night.

Some localized spots, particularly between Barrie and Orillia, may see totals exceeding 50 cm, with the potential for as much as 75 to 100 cm. However, model disagreement prevents us from confidently forecasting such extreme totals.

It’s important to note that snow squalls are highly localized phenomena, often only a few kilometres wide. While our forecasts aim to highlight the most likely zones, the reality is that squalls can shift unexpectedly, meaning not every location in a forecasted zone will see the same impacts.



Surrounding areas, including Orillia, Lindsay, Fenelon Falls, and Port Perry, could see localized snowfall of 15-25 cm from the Georgian Bay squall, with totals tapering quickly outside of this zone. Peterborough and areas along the Lake Ontario shoreline between Oshawa and Brighton may see 5-15 cm.

For regions east of Lake Huron, a narrow band from Goderich to Wingham and Listowel could see 25-50 cm of snow, with some extension into Kitchener, where totals may approach 15-20 cm. However, the exact setup will depend on the squall’s inland reach.



Elsewhere, the Golden Horseshoe could see a few centimeters of snow from brief, heavy bursts of lake effect activity, but no significant accumulations are expected. Areas north of Bracebridge, east of Peterborough, and south of Woodstock are likely to see little to no snow.

As always, lake effect snow forecasts carry inherent uncertainty. While many areas may receive less snow than forecasted, those directly in the path of these intense squalls could see the full brunt of the snowfall. Be prepared for rapidly changing conditions, and avoid non-essential travel in the hardest-hit zones.



Snow squalls are also expected to affect regions east and southeast of Lake Superior in Northern Ontario starting Wednesday evening. These squalls will continue to persist throughout the day on Thursday before shifting south of the border.

The Sault Ste. Marie region appears to be in the bullseye and could see localized snowfall totals between 25 to 50cm by the time the snow tapers off late Thursday.

Heavy Snow Could Impact New Year’s Eve Celebrations in Southern Ontario With Up to 10-20cm of Snow

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After a brief return to milder weather accompanied by heavy rain to cap off the final weekend of the year, a snowy blast is on the horizon to kick off the first few days of 2025.

A system is expected to move into Southern Ontario starting Tuesday afternoon, bringing a mix of precipitation that will gradually transition to snow as we ring in the New Year at midnight. For those heading out to celebrate New Year’s Eve, road conditions may become hazardous, particularly later in the evening as temperatures drop below freezing.



Snowfall is expected to continue throughout New Year’s Day on Wednesday, with the heaviest accumulation focused on parts of Central and Eastern Ontario. By the time the snow tapers off late Wednesday, some areas could see snowfall totals nearing 10 to 20 cm in the hardest-hit regions.

In the wake of this system, frigid Arctic air is set to return, dominating the weather pattern for at least the first week of 2025. With the Great Lakes still largely unfrozen, the lake-effect snow machine is expected to roar back to life, potentially resulting in a multi-day snow squall event.

Starting Thursday and continuing into the weekend, some areas in the traditional snowbelt regions near Lake Huron and Georgian Bay could see significant snowfall, with totals approaching 50 cm by the end of the weekend.



PRECIPITATION TYPE - MAP FROM WEATHERBELL

The New Year’s Eve system is forecast to bring the first scattered bands of precipitation into the region from the south and west during the early to mid-afternoon hours on Tuesday. Areas in Deep Southwestern Ontario and near the Lake Erie shoreline will be affected first, with the precipitation gradually spreading across Southern Ontario by the dinner hour.

At this time, most regions are expected to hover near or just above the freezing mark, particularly in the Golden Horseshoe, where temperatures are likely to range between 3 and 5°C. As a result, the precipitation will likely begin as scattered rain or drizzle in many areas.

However, higher elevations northwest of the Greater Toronto Area (GTA) and into Central Ontario may see a mix of rain, ice pellets, and wet snow as temperatures there will be closer to freezing.



PRECIPITATION TYPE - MAP FROM WEATHERBELL

By the evening, the heaviest precipitation is expected to be concentrated east of Lake Huron, extending into Central Ontario. This will increasingly fall as wet snow as temperatures cool. Meanwhile, regions near the shores of Lake Ontario and Lake Erie will see less sustained precipitation, with rain continuing to dominate, especially near the lakeshore.

As the clock strikes midnight to welcome the New Year, heavy snow will continue in Central & Southwestern Ontario, while moderate to heavy rain will likely persist along the Lake Ontario and Lake Erie shorelines, dampening New Year’s Eve celebrations in the GTA and Niagara region.



PRECIPITATION TYPE - MAP FROM WEATHERBELL

Overnight, the precipitation is expected to transition to heavy, wet snow across most areas as colder air moves in behind the system. However, areas close to the Lake Ontario shoreline, including Hamilton, Toronto, and Kingston, may continue to experience rain into the early hours of Wednesday. Wet snow may mix in later in the morning, but periodic rain is likely as temperatures hover near freezing throughout Wednesday afternoon.

Moderate to heavy snow is forecast to persist through Wednesday in Eastern and Central Ontario, tapering off in Southwestern Ontario by the evening. In Eastern Ontario, steady snow could continue past midnight, finally ending early Thursday morning. Some lake-effect snow may develop off Lake Huron and Georgian Bay as early as Thursday morning.



Snowfall totals are challenging to predict for this system due to temperatures hovering close to freezing, which could significantly impact snow accumulation. A slight shift in temperatures could cause the system to overperform or underperform expectations.

The highest snowfall totals are expected in higher elevations of Central and Eastern Ontario, including Sundridge, Huntsville, Algonquin Park, North Bay, Deep River, and Bancroft. These areas could see between 10 and 20 cm of fresh snow by Thursday morning.



A wide swath of Southern Ontario, including much of Eastern Ontario, the Lake Simcoe region, and parts of Southwestern Ontario, is forecast to receive between 5 and 10 cm of snow. Localized areas may exceed 10 cm and approach 15 cm.

Around 2 to 5 cm of snow is expected for Ottawa, Brockville, Kingston, Belleville, and the northern GTA (away from the shoreline), where mixing will reduce overall snowfall amounts.

Limited accumulation is expected near the shorelines of Lake Ontario and Lake Erie, as well as in Deep Southwestern Ontario, including Windsor and Chatham, where temperatures will likely remain too mild for significant snow accumulation.



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After the system snow, attention will shift to the risk of snow squalls beginning Thursday and lasting several days into the weekend. Snow squalls are highly localized events, often producing intense snowfall within narrow bands only a few kilometres wide which can make it hard to pinpoint exactly who will see the worst conditions.

Current models suggest a dominant northwesterly wind direction for much of this period, historically favouring heavy snowfall in parts of Grey and Bruce counties off Lake Huron. Squalls off Georgian Bay are expected to target Simcoe County (Midland, Orillia, Barrie), Muskoka (Bracebridge, Gravenhurst), and the Kawartha Lakes region.



Locations such as Orillia, Midland, Wasaga Beach, Wingham, Mildmay, Hanover, Chatsworth, Owen Sound, and Flesherton could see up to 50 cm of snow by the end of the weekend. However, not all areas will experience these extreme totals due to the localized nature of snow squalls.

Stay tuned for updates as higher-resolution models provide more precise forecasts. For now, be aware that travel in snowbelt regions could be significantly impacted starting Thursday, with the potential for rapid snowfall accumulation and blowing snow leading to near-zero visibility and possible road closures.

One Last Pre-Holiday Blast of Winter Could Make Travel Difficult in the Maritimes with up to 30cm of Snow

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There’s more snow on the way for the Maritimes following the storm over the weekend. The next system that will hit tomorrow, Christmas Eve, and continue into Christmas morning, will once again negatively impact the holiday travel plans for many across the region.



New Brunswick

The snow will start to push into Western New Brunswick around midnight tonight and spread eastward across the province before sunrise tomorrow. By that point, the snow will already have tapered of in the Northwest, leading to less than 5cm of accumulation in this area. As we progress through the morning, the snow will start to gradually diminish across western parts of Northern and Central New Brunswick as the system tracks southeastward.

Meanwhile, a bit of intensification is expected, leading to much of the province receiving over 10cm of snow by the end of the day. Pockets of particularly heavy snow are likely through the afternoon along the Fundy Coast, with the snow falling at up to 5cm/hr. This is expected to bring snowfall totals to over 20cm for this area, including Saint John, and over 30cm locally in areas of higher elevation.



The system will continue tracking southeastward across the province throughout the afternoon and early evening, at which time the entire system starts to fall apart. This will lead to scattered flurries lingering overnight and the early morning in Southeast New Brunswick.

Prince Edward Island

The snow will start in PEI a couple of hours before sunrise in Prince County, spreading across the rest of the Island throughout the morning and into the early afternoon. By the time the snow reaches the eastern edge of Kings County in the mid to late afternoon, this area will see snowfall for only a few hours before the system starts to break down. As a result, this area can expect less than 5cm of snow while the rest of the Island will receive upwards of 10cm.

There could be some lingering flurries for PEI overnight and into Christmas morning, but these will only add on another centimetre or two to the final snowfall totals.



Model run showing Snow (Blue) and Rain (green) at 4pM on Tuesday December 24th



Nova Scotia

The snow will make its way into both Northern and Western Nova Scotia from the northwest starting in the early morning before sunrise. It will push deeper across the province through the morning and early afternoon, but it is not expected to cross very far into Cape Breton, if at all. Isolated flurries can’t be completely ruled out here so our forecast is for up to 2cm of snow for this area.

The temperatures will rise throughout the day with the arrival of the storm and will climb above freezing in parts of Western Nova Scotia. Those living inland will see temperatures of 1°C, resulting in the buildup of heavier, wet snow. On the other hand, coastal communities in Yarmouth, Shelburne, and Queens Counties are expected to get up to 3°C and the snow will transition to rain, limiting overall snowfall totals to 5-10cm.

In the evening, the system will fall apart, leading to pockets of precipitation occurring across the Mainland for a few hours. Later into the evening and overnight, the snow is expected to persist over Western Nova Scotia and with temperatures remaining a degree or two above freezing, the snow that falls will be very wet and mixed with some rain. This will bring snowfall totals closer to 20cm and locally higher for parts of the Annapolis Valley.



This system is unfortunately very ill-timed and will really impact the plans that many people have to travel and visit family over the next couple of days. Thankfully, most of the snow will be finished by Christmas morning so day-of holiday travel shouldn’t be too tough.

Wind gusts should top out at about 50km/h on Tuesday, with the strongest gusts expected in Southern New Brunswick and Western Nova Scotia so visibility could be limited at times with brief whiteouts, but we won’t be at risk for full blizzard-like conditions.

Since the chances for a White Christmas across the Maritimes seem fairly obvious at this point, with Guysborough County and Southern Cape Breton just hitting the 2cm threshold along with the arrival of even more snow on Christmas Eve, we will not be updating our preliminary White Christmas Forecast. Enjoy your White Christmas everyone!

A Nightmare Before Christmas as Snowstorm Targets Southern Ontario on Monday With Up to 10-20cm of Snow

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Are you dreaming of a White Christmas? Well, it looks like luck is on your side as a snowy system is poised to sweep across Southern Ontario just days before Christmas. However, this snowfall won’t come without consequences, as it is expected to bring a significant amount of snow to some areas and could disrupt holiday travel plans right before Christmas.



Snow is anticipated to start early Monday and persist throughout the day, bringing moderate to heavy snowfall across a wide area of the region. Central and Eastern Ontario are likely to bear the brunt of this storm, with total snowfall amounts ranging from 10 to 20cm expected by early Tuesday morning.

In contrast, Deep Southwestern Ontario and areas along the Lake Ontario shoreline, including the Greater Toronto Area GTA, are expected to experience lesser impacts from this system. This is primarily due to the majority of the precipitation staying further north, and any moisture reaching the south being met with slightly warmer air, resulting in wetter snow and reduced accumulation.



HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

According to the latest data, initial bands of snow are projected to move into the Bruce Peninsula and Georgian Bay areas by mid to late morning on Monday. The snow will then spread eastward, encompassing Eastern Ontario and all regions by early afternoon.

The heaviest snowfall is likely to be concentrated east of Georgian Bay, possibly enhanced by minor lake effects. By late afternoon, snowfall will also begin in Southwestern Ontario, with a chance of some mixing, including ice pellets and wet snow, particularly in Deep Southwestern Ontario around Windsor.



HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The most challenging conditions are expected during the afternoon and evening hours, as steady snow covers much of Southern Ontario. Occasional moderate wind gusts up to 40 km/h may lead to blowing snow and reduced visibility. If travel is necessary during this time, exercise extreme caution, and consider postponing travel until Tuesday when conditions are expected to improve significantly.

Temperatures are forecasted to gradually warm up during the evening, approaching the freezing mark around Lake Ontario and Lake Erie. This may cause existing snow to transition to a mix of wet snow and rain, potentially resulting in lower snowfall totals in these areas.



Light snow will continue past midnight into early Tuesday morning but will diminish in intensity as the night progresses. Western regions should see snow taper off shortly after midnight, while Eastern Ontario may experience lingering snow until late morning.

Overnight, there is concern about rain mixing in along the Golden Horseshoe as temperatures rise further, potentially melting any earlier snow and jeopardizing the chances of a White Christmas in those areas. We will closely monitor this development as it unfolds.



Snowfall accumulation is expected to range from 10-20cm across Central and Eastern Ontario, including areas like Grey-Bruce, Barrie, Orillia, Huntsville, North Bay, and the Ottawa Valley. Some localized spots, particularly east of Georgian Bay and into the Ottawa Valley, could see up to 25cm of snow.

Further south and west, 5-10cm of snow is anticipated east of Lake Huron, extending into the Golden Horseshoe away from the shoreline, including cities like London, Woodstock, Kitchener, Guelph, Mississauga, and Orangeville.



Toronto, Oakville, Burlington, Hamilton, the Niagara region, and Deep Southwestern Ontario, such as Chatham, Sarnia, and Windsor, are expected to receive less than 5cm of snow. Windsor may see minimal snow if the transition to rain occurs earlier than anticipated. There remains a possibility for the GTA to exceed forecasted amounts if cold air persists and prevents mixing.

A Rare Region-Wide White Christmas Appears to be in Store for the Entire Maritimes This Year

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White Christmases are not a common occurrence for the Maritimes, especially for the entire region, since the late fall is typically mild and rainy. They are so rare in some parts of the region that it has been over a decade since one was last experienced. This year has been fairly average up until very recently and with Christmas now only 3 days away, the odds of a White Christmas across the Maritimes is becoming quite clear.



According to Environment Canada, in order for an area to have a White Christmas, there needs to be at least 2cm of snow on the ground as of 7am on Christmas Day. After Saturdays’s Nor’easter, the snowpack across most of the region is at least 5cm deep. The exception to this is in Guysborough County and into Southern Cape Breton Island, where rain and positive temperatures ended up melting some of the snow that had already fallen from the storm. At this point, it looks like this area just barely reaches the 2cm threshold for a White Christmas.

Looking ahead to the next few days, temperatures reaching only a degree or two above freezing in some areas and the arrival of more snow on Christmas Eve will help solidify the chances for a White Christmas across the Maritimes.

Modelled Snow depths, in centimetres, as of Sunday, December 22nd at 8am aT.



New Brunswick

Temperatures across most of the province are expected to remain below freezing between now and Christmas morning so the snow that is already on the ground is here to stay. A system moving in early Tuesday morning will bring snow to the entire province throughout the day. The heaviest snow is expected to fall in Southern New Brunswick and up to 20cm may accumulate. Although temperatures along the Fundy Coast may creep into the single digits on Tuesday with the arrival of this system, it won’t be enough to melt all of the existing and incoming snow. As a result, all of New Brunswick can expect a White Christmas.

Prince Edward Island

Similar to New Brunswick, temperatures across PEI are expected to remain below 0°C until after Christmas morning. Snow will reach the province before sunrise on Christmas Eve and continue into the evening, adding to the existing snowpack and guaranteeing a White Christmas for the entire Island.

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Nova Scotia

The chances for a White Christmas vary slightly across Nova Scotia. Given the shallow depth of the snowpack in parts of Eastern Nova Scotia, chances are high, but not a guarantee and just a little bit of melting could spoil things. Luckily as of now, it appears that any melting might not happen in this area until the afternoon on Christmas Day when temperature rise above the freezing mark.

Snow is expected to move into Western Nova Scotia early Tuesday morning and will cross the province through the remainder of them morning. Although it is expected to be light and fairly brief, the additional snow will be welcome news for those in Eastern Nova Scotia who are hoping for that traditional White Christmas. This extra snowfall keeps the odds of a White Christmas high in the areas of shallow snowpack, barring any major melting that might occur a little ahead of schedule.

The snow will be heavy at times across parts of Western Nova Scotia, leading to over 10cm of accumulation. Temperatures in this area are anticipated to climb into the single digits, particularly along the shorelines, so it’s possible that there will be a transition over to rain, but this isn’t expected to be enough to ruin the chances of a White Christmas. Some weather models are even suggesting that the snow could continue to fall in Western Nova Scotia into Christmas morning, leading to what some consider to be a “true” White Christmas!



Please keep in mind that this is just a preliminary forecast, along with the first look at the incoming snowfall, and this is based on current data. The full forecast for the incoming snow will be posted Monday afternoon/evening and the final White Christmas forecast is coming Christmas Eve morning. Make sure to stay tuned!

A White Christmas is in the Forecast for Most of the Prairies, Odds are Not Good in Southern Alberta

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The second half of November and all through December have been marked by a series of snowstorms and periods of frigid temperatures across the Prairies. With Christmas only four days away, the odds of a White Christmas are becoming clearer.



According to Environment Canada, in order for an area to have a White Christmas, there needs to be at least 2cm of snow on the ground as of 7am on Christmas Day. This is typically an easy threshold to cross in the Prairies and it appears that this year will be no different for most, but not all.

Currently, the snowpack is considerable across the Prairies, at least 10cm deep across a majority of the regions and large swatch where the snow is over 20cm in all three provinces. There are a few pockets where this is the exception, particularly in Southern Alberta where warm temperatures early in the week have resulting in little to no snow on the ground. Looking ahead over the next few days, some warmer air and a mix of rain and freezing rain will decrease the likelihood of a White Christmas for some.



Modelled Snow depths as of Saturday, December 21st at 6am CT.

Manitoba

Northern Manitoba may see some scattered flurries this evening and overnight and again Tuesday morning. Otherwise, there is no other fresh snow expected between now and Wednesday morning. Temperatures will remain below freezing across the province until Christmas morning so no melting of the existing snow is expected. As a result, all of Manitoba can expect a White Christmas.

Saskatchewan

Like Manitoba, Northern Saskatchewan may see scattered flurries over the next few days, but no significant snowfall is expected. There is, however, a threat to White Christmas chances in Southwest Saskatchewan.

Early Sunday morning, temperatures in this area will climb to above freezing and will stay there throughout most of the day. Not only will this melt some of the limited snowpack in the area, a mix of rain and freezing rain will also result in melting. Temperatures are expected to rise once again on both Monday and Tuesday. With no additional snow in the forecast, a White Christmas can not be guaranteed in this area, but it is not completely ruled out.



Alberta

The chances for a White Christmas will vary across Alberta. A large part of Southern Alberta already has less than 5cm of snow on the ground and daily highs in the single digits between now and Christmas significantly impact the chances of a White Christmas here. The relative warmth will also stretch northward, just east of the Rockies over the coming days, but the greater snowpack and temperatures only reaching a degree or two above freezing will keep the hopes for a White Christmas alive.

The only fresh snow in the forecast for the province will be isolated to the Mountains and far Northern Alberta. There’s the chance for some rain to cross through Southern Alberta overnight and through Sunday morning which will further hinder the likelihood of a White Christmas in the area.



Please keep in mind that this is just a preliminary forecast and is based on current data. The forecast will be updated over the coming days, with the final forecast set to be posted on Christmas Eve. Make sure to stay tuned!

It’s a Christmas Miracle! A White Christmas Is Likely for Most of Ontario & Quebec This Year

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The month of December has truly delivered a winter wonderland for much of Ontario and Quebec, especially in the snowbelt regions of Ontario, which have seen significant snowfall from several rounds of snow squalls in recent weeks.

With Christmas just around the corner—less than five days away—the question on everyone’s mind is whether we’ll wake up to a White Christmas or a Green Christmas this year.



For clarity, Environment Canada defines a "White Christmas" as having at least 2 cm of snow on the ground at 7 a.m. Christmas morning. Unfortunately, in recent years, Southern Ontario’s holiday season has often been marked by the Grinch’s meddling, with last year seeing widespread "Grinchmas" conditions.

Currently, the snowpack across much of the region is quite substantial, particularly east of Georgian Bay, into Northern Ontario, and across Quebec. The good news for these areas is that the forecast suggests little to no rain or mild temperatures between now and Christmas, making a White Christmas virtually guaranteed.



However, the story is quite different for southern portions of the region, including Deep Southwestern Ontario and the Golden Horseshoe. These areas haven’t seen much in the way of significant snowfall accumulation this month, and the forecast includes a stretch of above-freezing temperatures on Christmas Eve and Christmas Day.

As a result, the odds of a White Christmas here depend entirely on whether snow can accumulate between now and Christmas morning.

Thankfully, hope isn’t entirely lost! A developing system is expected to move into Southern Ontario early Monday, continuing into Christmas Eve on Tuesday. Recent model updates have been promising for snow lovers, trending toward a stronger system that brings more widespread snowfall.



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Current projections suggest this system could deliver 10–20 cm of snow across Central and Eastern Ontario. However, for those along the Lake Ontario and Lake Erie shorelines, including parts of the GTA and Niagara Region, snowfall amounts may be significantly lower due to temperatures rising above freezing during the day on Monday. This could lead to melting or even a mix with rain, reducing accumulation to just a few centimeters.

With temperatures hovering slightly above freezing through Christmas Eve, it’s uncertain whether any snow from this system will survive until Christmas morning in these areas.



WHITE CHRISTMAS REGIONAL BREAKDOWN

Central Ontario, including Muskoka, Tobermory, Bancroft, and Algonquin Park, has the best odds in Southern Ontario. These areas already boast a healthy snowpack from earlier systems and lake-effect snow, and Monday’s storm will only add to it. Temperatures are expected to remain below freezing, ensuring the snow sticks around. The chance of a White Christmas here is over 90%.

Eastern Ontario and areas near Lake Huron, including the Ottawa Valley and regions around Lake Simcoe, have a slightly lower chance at 75%. Eastern Ontario currently has little snow on the ground, but Monday’s system is expected to change that. Lake Huron’s shoreline, while already snow-covered, will face a brief warm-up Monday into Christmas Eve. While the snow is likely to hold, it isn’t guaranteed.



For areas like Sarnia, London, Kitchener, Guelph, and Belleville, the chance of a White Christmas is more uncertain at 50%. Everything depends on how much snow Monday’s system delivers and whether it can survive the milder temperatures leading into Christmas morning.

In the GTA, including Hamilton and northern parts of Niagara, the odds of a White Christmas are slim with a 25% chance. Without an existing snowpack and with limited accumulation expected from Monday’s storm, above-freezing temperatures are likely to melt any snow that does fall. However, if the storm overperforms or the warm-up is less intense, we could see a last-minute boost in probabilities.



Deep Southwestern Ontario, including Windsor and areas along the Lake Erie shoreline, is the least likely to see a White Christmas, with just a 10% chance. Monday’s system is forecast to bring minimal snow, and the prolonged warm-up will likely ensure a Green Christmas here.



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Northern Ontario offers little drama in this forecast. With widespread snow on the ground and no significant warm-up in sight, the region enjoys a 90%+ chance of a White Christmas across the board.

Much of Quebec also looks set for a picturesque holiday. The exception is the Montreal area, which currently has limited snow on the ground. However, like Eastern Ontario, this should change once Monday’s system moves through.



This forecast remains preliminary and will be updated as we approach Christmas. Our final White Christmas forecast, set to be released on Christmas Eve, will factor in Monday’s storm and provide a clearer picture. If the snow cooperates, expect to see more 90%+ zones on the map. Stay tuned, and let’s hope for a festive, snow-covered holiday!

Pre-Christmas Squalls Could Bring Up to 25-50cm of Snow on Saturday to Parts of Southwestern Ontario

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As we approach the final weekend before Christmas, Southern Ontario is gearing up for the coldest air of the season so far. With the lakes still unfrozen after the unseasonably mild fall, conditions are setting up perfectly for the lake effect snow machine to roar back to life, particularly off Lake Huron.



Lake effect snow squalls are expected to develop as early as Friday evening along the southern shoreline of Lake Huron and persist through much of Saturday. Current indications suggest the heaviest snowfall will target the corridor between Sarnia and Strathroy. By the time the squalls taper off late Saturday, some areas could be buried under 25 to 50 cm of fresh snow.

This snowfall is promising news for those hoping for a White Christmas. With below-freezing temperatures expected to last through Tuesday, the snow should be deep enough to hold on despite a brief warm-up on Christmas Eve into Christmas Day when temperatures may climb above freezing.



HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Based on the latest data, a fairly intense snow squall is anticipated to form around midnight, likely affecting areas between Petrolia and Strathroy. However, the exact location of this band remains uncertain and will determine which areas see the most significant snow. The best bet at this time places the heaviest snow over Port Franks, Lambton Shores, and Kettle Point.

The squall is expected to persist through the overnight hours into early Saturday morning, bringing dangerous travel conditions in the affected regions. Rapidly accumulating snow combined with near-zero visibility will likely lead to road and highway closures. There’s also potential for the squall to extend further inland, possibly reaching areas northeast of Chatham along the Lake Erie shoreline.



Meanwhile, locations along the eastern shoreline of Lake Huron, from Kincardine to Grand Bend, may experience occasional bursts of heavy snow as the squall shifts and clips the shoreline.

By late Saturday morning and into the afternoon, the lake effect activity south of Lake Huron is expected to weaken as the band becomes more spread out and less organized. The squall should gradually diminish and retreat closer to the shoreline by Saturday evening, eventually fizzling out overnight into early Sunday morning.

In addition to the Lake Huron squalls, minor lake effect activity is possible south of Georgian Bay, including areas like Owen Sound, Meaford, and Collingwood. However, this activity is not expected to be as intense, with light to moderate snowfall likely throughout the day on Saturday.



When it comes to snowfall accumulation, variability is the nature of lake effect events. Narrow squalls can lock into a region and dump significant snow over a small area while sparing nearby locations.

We currently expect areas including Warwick, Watford, Forest, and Lambton Shores to receive between 25 to 50 cm of snow by the end of Saturday, with localized totals possibly exceeding 50 cm in some spots, although this is likely an overestimate.

The gradient will be sharp, with Petrolia and Grand Bend potentially seeing 15 to 25 cm. Sarnia and Strathroy, on the outskirts of the main activity, are likely to receive just 2 to 5 cm, although even a slight shift in the squall’s position could put these areas into the heavier snow zone.



Further up the eastern Lake Huron shoreline, locations from Kincardine to Grand Bend could see 5 to 15 cm of snow, with most areas leaning toward the lower end of that range.

South of Georgian Bay, including Owen Sound, Meaford, and Collingwood, snowfall is expected to range between 2 to 5 cm, with localized amounts up to 10 cm possible if the activity becomes more organized.

Elsewhere, the Niagara Region could pick up 2 to 5 cm of snow overnight into early Saturday morning as lingering precipitation from a previous system continues.



For the rest of Southern Ontario, no significant snowfall is expected this weekend. However, we are closely monitoring a potential snowmaker early next week between Monday and Tuesday, which has been trending stronger in recent model data. This system could bring heavy snow to parts of Southern Ontario, maybe sealing the deal on a White Christmas for many. We’ll provide more details on that in a separate forecast.

Nor'easter With Intense Snow Will Hinder Pre-Holiday Travel and Almost Promise a White Christmas in the Maritimes

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It is going to start to look like Christmas across the Maritimes this weekend. The Nor’easter mentioned in yesterday’s preliminary forecast is making its way towards the Maritimes and will reach our shores this evening. While the low pressure center will pass south of Nova Scotia, the storm will bring 20-30cm of snow across some or all of the three Maritimes provinces.



Nova Scotia

Light snow will begin in Western Nova Scotia this evening, around 7-9pm, and spread eastward across the province throughout the remainder of the evening and overnight. The snowfall will quickly intensify, falling at close to 5cm/hr in some areas and continuing for several hours. This period of intense snow will result in widespread snowfall accumulations 20-30cm and possibly even higher locally before sunrise for most of mainland Nova Scotia.

In Guysborough County and into southern parts of Cape Breton Island, the snow will transition to ice pellets for a couple of hours, starting at around 3am as some of the warmer air from the storm pushes northward. This will limit snowfall totals in the area to 10-20cm.



Model run showing Snow (Blue), Rain (green), and Ice Pellets (Orange) at 4AM

The eastern half of the province will see a break in the precipitation before dawn, but the heavy snow will taper to light snow in the west which will continue through the morning. By noon, that snow will start to push eastward, possibly with a bit of light rain preceding it. The snow will start to taper off in Western Nova Scotia in the mid-afternoon and should end for most of the province by the evening. Some stray flurries will linger overnight and into Sunday morning, by they will provide very little additional accumulation.



New Brunswick

The entirety of New Brunswick can expect snow from this Nor’easter, but given its offshore track, the heaviest snow will be in the southeast and totals will decrease going northwest.

The snow will reach the Fundy Coast around midnight tonight and spread northward during the early morning hours. Southeastern New Brunswick can expect some heavy snow for a couple of hours that will quickly drive up accumulations. The snow will begin to taper off after sunrise, starting in the northwest and gradually through to the southeast by Saturday evening. This will bring snowfall totals in the southeast corner of the province above 20cm by the end of the day.

Prince Edward Island

The leading edge of the Nor’easter will cross into PEI shortly after midnight tonight. The snow will be continuous and last straight through to late Saturday evening. The snow will be heavy at times across the Island, falling at up to 2cm/hr and while not as heavy as expected in Nova Scotia, this will be enough to result in over 20cm of snow for the entire province.



Given that this is one of the busiest weekends of the year for travel, this storm will likely result in many headaches across the Maritimes. Heavy snow is already a pain to drive in, but widespread wind gusts up to 60km/h, and locally as high as 80km/h, will lead to blowing snow throughout the day Saturday. Not only will the roads be treacherous, but airports will likely have a handful of delays and cancellations due to the storm. Please give yourselves plenty of extra time if going out on Saturday and if possible, consider postponing any travel until Sunday.

For those who look at this storm as the chance for a White Christmas in over a decade in some places, there’s good news! Temperatures are not expected to climb above freezing until later next week so the snow will stick around.

Dreaming of a White Christmas? Incoming Storm Will Almost Guarantee One for the Maritimes!

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It hasn’t really looked like the holiday season across the Maritimes lately, with grass still visible throughout the region. There’s been very little snowfall in Nova Scotia and PEI and the existing snowpack in New Brunswick melted just last week. A skiff of snow fell across New Brunswick overnight and this morning, but that’s the extent of the snow on the ground for pretty much the entire region. For those in the Christmas spirit though, that’s all about to change.



Starting Friday evening, a Nor’easter will move into the region that is expected to bring considerable heavy snow across most of Nova Scotia and into PEI and Southeastern New Brunswick. Weather models are currently projecting widespread snowfall accumulations of 20-30cm for that particular area and lower totals for the remainder of New Brunswick by Saturday evening.

The amount of snow expected in Guysborough County and much of Cape Breton Island is lower because some mixed precipitation is expected. Where, and how much of, this mixed precipitation falls will be entirely dependent on the track of the storm and there is still a bit of remaining uncertainty in that regard.



While some may be celebrating the likelihood of a White Christmas, the snow will certainly have negative impacts on early holiday travel this weekend. Not only will the heavy snow be a chore to drive in, widespread wind gusts up to 60km/h, and locally as high as 80km/h, will create even more hazardous conditions due to blowing snow. On top of that, there is the possibility of some isolated power outages with the strong winds.

This is only our preliminary look at the storm so check back tomorrow for a more in-depth forecast once the track of the storm becomes a bit clearer.