⛈️Severe Thunderstorm Risk, More Freezing Rain, Heavy Rain, Snow, and Strong Wind Gusts on Wednesday in Ontario

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Spring storms are here, and this one is bringing a bit of everything. It will begin Wednesday morning delivering heavy rain, freezing rain, strong wind gusts, severe thunderstorms and snow depending on your location. Southwestern Ontario will see significant rainfall and a severe thunderstorm risk, while parts of central, eastern, the golden horseshoe and northeastern Ontario could face a messy mix of freezing rain, ice pellets, rain, snow and strong wind gusts, again, depending on your location. For those still recovering from last weekend’s ice storm, this storm could certainly add to the challenges. There’s also a risk for substantial snowfall in northwestern Ontario, specially in the Thunder Bay region. Further details on each area below.


⛈️Severe Thunderstorm Risk

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💨🌪️ Hazard(s): Wind, Tornado, Thunderstorms
📍 Location: Extreme southwestern Ontario
Timing: Late Wednesday afternoon and evening.
⚠️ Impact(s): Loose objects may be tossed, possible power outages

🔎 Confidence: Low
💥 Impact: High

A line of severe thunderstorms could cross into the province from Michigan, possibly producing wind gusts up to 100 km/h. A brief tornado is also possible on this line. There is lots of uncertainty in this occurring as ingredients to form these thunderstorms are located well south of the border and will rely on the thunderstorms being able to develop there and reach southwestern Ontario before weakening. Refer to the Wednesday Significant Weather discussion for rainfall information.


🌧️ Heavy Rain, 🧊 Ice, 💨 Strong Wind Gusts, and ❄️ Snow

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📍 Location: Southwestern Ontario

🌧️ Hazard(s): Rain
📍 Location: Southwestern Ontario
Timing: Wednesday morning into Thursday morning
⚠️ Impact(s): Possible flooding in low-lying areas

🔎 Confidence: Moderate
💥 Impact: High

Rain is expected and may be accompanied by thunderstorms. Rainfall amounts up to 60 mm are possible by late Wednesday evening, with additional amounts expected on Thursday. Totals will vary, with areas east of Lake Huron receiving up to 60 mm, while regions near Lake Erie will likely see 10 to 20 mm.


📍 Location: Grey and Bruce Counties east to Peterborough

🧊🌧️ Hazard(s): Ice, Rain
📍 Location: Grey and Bruce Counties east to Peterborough
Timing: Wednesday midday into Thursday morning
⚠️ Impact(s): Possible flooding in low-lying areas, broken tree branches from ice build-up

🔎 Confidence: High
💥 Impact: High

Freezing rain, possibly mixed with ice pellets, is expected to bring 4 to 8 mm of ice accretion on some surfaces, particularly over higher terrain. Rain will follow and may be accompanied by thunderstorms. Rainfall amounts up to 40 mm are possible by late Wednesday evening, with more rain on Thursday.

⚠️ Impacts in this area may be enhanced due to recovery efforts from last weekend’s ice storm.


📍 Location: East of Lake Huron to portions of the Greater Golden Horseshoe

🌧️🧊 Hazard(s): Rain, Ice
📍 Location: East of Lake Huron to portions of the Greater Golden Horseshoe
Timing: Wednesday midday into Thursday morning
⚠️ Impact(s): Possible flooding in low-lying areas, possible icy surfaces on roads and walkways.

🔎 Confidence: Moderate
💥 Impact: High

A brief period of freezing rain is expected Wednesday afternoon, bringing 1 to 2 mm of ice accretion on some surfaces, particularly over higher terrain. Rain will follow and may be accompanied by thunderstorms. Rainfall amounts up to 50 mm are possible by late Wednesday evening, with more rain on Thursday.


📍 Location: Parts of Central, Eastern and Northeastern Ontario

❄️🧊 Hazard(s): Snow, Ice
📍 Location: East of Lake Huron to portions of the Greater Golden Horseshoe
Timing: Wednesday midday into Thursday morning
⚠️ Impact(s): Broken tree branches from ice build-up, possible difficult travel conditions

🔎 Confidence: Moderate
💥 Impact: High

A messy mix of winter precipitation is expected. Snow mixed with ice pellets will develop near midday Wednesday, with up to 5 cm possible before transitioning to freezing rain. A period of freezing rain Wednesday evening could bring 3 to 6 mm of ice accretion, especially over higher terrain.


📍 Location: North shore of Lake Ontario

🧊🌧️ Hazard(s): Ice, Rain
📍 Location: North shore of Lake Ontario
Timing: Wednesday midday into Thursday
⚠️ Impact(s): Possible icy surfaces on roads and walkways, possible flash flooding and water pooling on roads

🔎 Confidence: Moderate
💥 Impact: Low

A brief period of ice pellets or freezing rain is possible Wednesday afternoon. Rain will follow and may be accompanied by thunderstorms. Rainfall amounts up to 20 mm are possible by late Wednesday evening, with additional amounts expected on Thursday.


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📍 Location: Southern portions of Northeastern Ontario and portions of Eastern Ontario

❄️🧊 Hazard(s): Snow, Ice
📍 Location: Southern portions of northeastern Ontario and portions of eastern Ontario
Timing: Beginning midday Wednesday
⚠️ Impact(s): Difficult travel conditions

🔎 Confidence:
💥 Impact:

A messy mix of winter precipitation is expected. Snow mixed with ice pellets will develop Wednesday afternoon, with up to 5 cm possible before transitioning to a brief period of freezing rain.

⚠️ Confidence in ice accretion amounts is low. However, accretion is expected to remain fairly low as the freezing rain transitions to rain Wednesday night.


📍 Location: West of Lake Superior

❄️🌬️ Hazard(s): Snow, Blowing Snow
📍 Location: West of Lake Superior
Timing: Wednesday morning into Thursday morning
⚠️ Impact(s): Difficult travel conditions, reduced visibility, possible road closures

🔎 Confidence:
💥 Impact:

Snowfall amounts up to 25 cm are possible, with locally higher totals over elevated terrain. Gusty winds could lead to local blowing snow, especially near Lake Superior. Additional snowfall is expected Thursday.


📍 Location: Northwestern Ontario and north of Lake Superior

❄️ Hazard(s): Snow
📍 Location: Northwestern Ontario and north of Lake Superior
Timing: Wednesday morning into Thursday morning
⚠️ Impact(s): Difficult travel conditions

🔎 Confidence:
💥 Impact:

Snowfall amounts up to 15 cm are possible, with additional snowfall expected Thursday.


Final Thoughts:

This is shaping up to be a potentially strong system with widespread rain, ice, and snow affecting much of Ontario. Flooding, icy roads, tree damage, and power outages are all possible. For areas still recovering from last weekend’s ice storm, even small amounts of ice could exacerbate existing damage. The severe thunderstorm risk in deep southwestern Ontario is of particular concern as well.

As always, keep an eye our latest updates and prepare for rapidly changing conditions. Stay safe out there, folks!


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

Dangerous Ice Storm Likely This Weekend With Widespread Power Outages Across Parts of Southern Ontario

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Concern is rapidly growing for what is shaping up to be a potentially devastating ice storm this weekend across parts of Central and Eastern Ontario. Prolonged freezing rain, beginning Friday evening, is expected to persist throughout much of the weekend, leading to substantial ice accretion on exposed surfaces.

This storm has the potential to reach ice accumulation levels not seen in years—or even over a decade. With up to 40mm of ice accretion possible, widespread power outages are likely in the hardest-hit regions, including Muskoka, Simcoe County, Kawartha Lakes, Peterborough, and Kingston.

Some of these power outages could last for days or even weeks, especially in more rural areas with dense tree coverage. Trees weighed down by ice are likely to fall, taking power lines with them. Travel conditions will also be significantly impacted, as ice-covered roads become extremely dangerous.

For Northern Ontario, the storm will start as a classic winter system, bringing heavy snowfall to Northeastern Ontario throughout Saturday. A second round of precipitation on Sunday could introduce freezing rain and ice pellets further south, affecting areas like Elliot Lake, Sudbury, and North Bay. Snowfall totals in Northeastern Ontario are expected to range from 20 to 30cm, making travel difficult.

Even the Ottawa Valley will see significant snowfall, with up to 20cm possible, along with a mix of ice pellets. By Sunday, freezing rain could become a concern for the region as temperatures rise and the precipitation type shifts.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

As of Friday afternoon, rain is already moving into Southwestern Ontario. By the evening, precipitation will spread north and east into Central and Eastern Ontario.

Based on the latest data, a band of heavy snow is expected to develop along a corridor stretching from Sudbury through North Bay and into the Ottawa region. To the south, an area of freezing rain will form over the Bruce Peninsula and extend into regions around Lake Simcoe.

ESTIMATED TEMPERATURE - MAP FROM WEATHERBELL

How far south the freezing rain spreads remains uncertain. Model guidance suggests surface temperatures will hover near the freezing mark across Barrie and the Greater Toronto Area (GTA).

Even a fraction of a degree difference could significantly alter how much freezing rain accumulates. If the air remains colder than expected, freezing rain could be more widespread. However, a slightly warmer scenario would push the freezing rain line further north.

Confidence is highest for freezing rain in northern sections of Simcoe County, Kawartha Lakes, and Muskoka. These areas are most likely to remain below freezing for an extended period, allowing heavy ice accretion to build up.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The most intense icing is expected overnight into early Saturday morning. The worst conditions will stretch from Muskoka through Peterborough and into Kingston.

Once again, temperature will be the deciding factor. Some areas, such as Barrie and Newmarket, sit right on the edge between freezing rain and regular rain. If cold air lingers longer than anticipated, freezing rain could extend as far south as the northern GTA, as well as higher elevations like the Dundalk Highlands.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Through Saturday morning and afternoon, light to moderate freezing rain or drizzle is expected to persist across portions of Central Ontario, particularly around Lake Simcoe. However, the intensity will decrease compared to the earlier hours.

Further south, rain will continue across Southwestern Ontario and the GTA. This is when we expect the warmest temperatures of the storm. Some areas in Deep Southwestern Ontario, including Windsor, could surge into the 20s, while Central Ontario remains near or below freezing.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

By Saturday evening, another round of heavy precipitation is expected to push into Central Ontario. At the same time, temperatures will steadily drop. Regions that saw rain in the afternoon—including parts of the GTA and Barrie—may transition back to freezing rain.

ESTIMATED TEMPERATURE - MAP FROM WEATHERBELL

Model data suggests that by late Saturday night into Sunday morning, the freezing rain line could shift southwest of the GTA. This could result in several hours of freezing rain across Kitchener, Waterloo, and parts of the Toronto area.

Deep Southwestern Ontario, including Windsor, Sarnia, and London, is expected to remain unaffected, staying well above freezing.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Sunday morning will bring a gradual transition from freezing rain to regular rain across the GTA as temperatures climb above freezing. However, elevated areas northwest of the city, such as Guelph, Orangeville, and Shelburne, could see freezing rain linger for a few extra hours.

For Central Ontario, the freezing rain will continue into early Sunday afternoon as the main area of precipitation slowly shifts north.

By Sunday afternoon, the Ottawa Valley may begin transitioning from snow to ice pellets and then to freezing rain as temperatures rise.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Most of Southern Ontario will warm above the freezing mark by late Sunday, finally pushing the freezing rain threat northward.

However, by Sunday night into Monday morning, the risk of freezing rain will shift to Northeastern Ontario, including Sudbury and North Bay.

Meanwhile, heavy snow and ice pellets will impact more northern regions, such as Wawa and Timmins.

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Predicting exact ice accretion remains challenging, as many factors influence how much ice actually builds up. The amount of freezing rain you experience may vary significantly from nearby areas due to microclimate effects, surface conditions, and temperature fluctuations.

Some high-resolution model runs suggest an extreme scenario with localized pockets of over 50mm—possibly even 75mm—of freezing rain. However, because much of this precipitation will fall in a relatively short timeframe, not all of it will necessarily adhere to surfaces.

Given this, we are forecasting general ice accretion between 25 and 40mm in the hardest-hit areas. This includes the northern tip of the Bruce Peninsula, Muskoka, Orillia, Barrie, Orangeville, Collingwood, Lindsay, Peterborough, Belleville, and Kingston.

If temperatures are slightly colder than expected, some locations could exceed 40mm of ice accretion, particularly where conditions allow for more efficient accumulation.

To put this into perspective, we can use the Sperry-Piltz Ice Accumulation Index (SPIA Index). With forecasted ice accumulations of 25-40mm (1-1.4”), this storm falls into a Category 4 ice event—even before factoring in wind.

While we are not expecting extreme winds, gusts of 40-50km/h (25-30 mph) in some areas could push this storm into Category 5 territory. According to the SPIA Index, a Category 5 ice storm results in:

Catastrophic damage to entire exposed utility systems, including both distribution and transmission networks. Outages could last several weeks in some areas. Shelters needed.

For the Greater Toronto Area (GTA), ice accretion amounts will vary significantly. The biggest factor will be how long cold air remains trapped at the surface.

We currently expect between 10-15mm of ice for northern parts of the GTA, including York, Durham, and Peel regions. Kitchener and Waterloo will likely see between 5-10mm.

Closer to the Lake Ontario shoreline—including downtown Toronto—freezing rain amounts should be lower, around 2-5mm. However, if temperatures are colder than expected, ice accretion in the GTA could be higher, so it’s still best to prepare.

To the north, ice accretion amounts will drop off as freezing rain transitions to ice pellets and snow closer to the Ottawa Valley.

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In terms of snowfall, widespread totals between 20-30cm are expected across much of Northeastern Ontario through Monday. This includes Sudbury, North Bay, Chapleau, Timmins, and Kirkland Lake. Even Thunder Bay could see 10-20cm of snow, mainly earlier in the weekend.

Along the Quebec border, snowfall amounts will range from 10-20cm in areas like the Ottawa Valley and Cornwall. Further southwest, freezing rain and ice pellets will be the dominant concern, leading to lower snowfall totals.

This storm remains highly dynamic, with small temperature fluctuations potentially making a massive difference in what type of precipitation falls. We will continue to monitor the latest data and provide updates as the situation evolves. Stay safe and stay prepared.

Significant Spring Storm Expected to Dump up to 20cm and Possibly Locally Higher Amounts Across the Prairies

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It’s simply not spring in the Prairies without at least one major snowstorm and this year will be no different! A low pressure system will track across the region over the next couple of days, bringing widespread 10-20cm to all three Prairie provinces by the end of the work week. What makes this storm more interesting is that while some areas could see up to 20cm of snow, others could see temperatures approaching 20°C, particularly in Southern Alberta and Southwest Saskatchewan!

The precipitation will begin Wednesday evening as rain across parts of Central Alberta. As the temperatures fall later in the evening, the rain will transition to snow, which will then spread both southward and eastward overnight and into early Thursday morning. A bit of rain will persist along the southern edge of precipitation into the morning, but it will eventually also transition over to snow, with a chance for some brief freezing rain in between.

Model Image showing the location and intensity of snow (Blue), Rain (Green), and Freezing rain (Pink) at 4AM MT Thursday

It’s during the early morning hours of Thursday that the snow will push into Saskatchewan while also starting to intensify across Central Alberta. As the morning continues, the heavy snow will cross into Saskatchewan, spreading southeastward across the province throughout the remainder of the morning and into the early afternoon. The snow will then spread into Southern Manitoba Thursday afternoon with the heavier snow beginning in the evening.

The heavy snow will fall for several hours, leading to rapid accumulation of up to 20cm across the region, with the possibility of pockets where up to 25cm could fall. The band of heavy snow will start to taper off early Friday morning, but light snow is expected to continue throughout the day, with the possibility of periods of heavier snow in both Saskatchewan and Manitoba.

Model Image showing the location and intensity of snow (Blue), Rain (Green), and Freezing rain (Pink) at 6PM CT Thursday

Wind gusts are expected to be up to 60km/h throughout the event and along with the heavy snow, travel may be difficult at times due to blowing snow. This could result in some isolated road closures in the hardest hit areas so make sure to check your local road conditions before going out over the next few days.

Up to 20cm of Additional Snow Expected With Second Storm of the Week

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The week of active weather continues in Maritimes with our second storm arriving late Wednesday, bringing a mixture of rain and snow to the region straight through to the end of the day Thursday.

This new system will move into Western Nova Scotia and Southwest New Brunswick Wednesday evening as mostly rain with a bit of snow. The precipitation with quickly spread eastward throughout the evening and subsequent falling temperatures will signal the beginning of the transition from rain to snow.

Model Image showing the location and intensity of snow (Blue), Rain (Green), and Freezing rain (Pink) at 2AM AT Thursday

After midnight, as the leading edge of the precipitation moves into Prince Edward Island, the snow will start to intensify in New Brunswick and Nova Scotia. The heavier snow will be somewhat scattered across New Brunswick, but it will be both more organized and heavier in Eastern Mainland Nova Scotia, Cape Breton Island and into Kings County, PEI.

The heavier snow is expected to persist through Thursday morning before tapering off in the early afternoon for Nova Scotia. Light snow is expected to continue in New Brunswick and PEI through the afternoon and evening, which will add a few more centimetres to the snowfall totals.

Eastern Nova Scotia, with the heaviest snowfall of the event, can expect up to 20cm by the end of the day Thursday. This will also be the case in eastern Kings County, PEI, while the rest of the Island can expect up to 10cm. Most of New Brunswick will see less than 5cm, but the heavier snowfall overnight, mixed with the lingering light snow throughout Thursday will drive totals up to 10cm in the east and into the Acadian Peninsula.

There’s the possibility of some brief snow on Friday that would only bring a couple of centimetres to the region and a significant storm on Saturday looks like it may stay offshore, but if that changes, we will provide updates!

⚠️ Significant Winter Storm Risk For Ontario This Weekend With Three Days of Freezing Rain Possible 🚨

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It may say spring on the calendar but Ontario could get a rude reminder that winter is not done with us quite yet! ❄️🥶 Environment Canada meteorologists are forecasting the potential for a significant winter storm this weekend that could bringing several days of freezing rain, causing icy roads, tree damage, and possible power outages across much of Southern Ontario.

*To clarify, “Southern” Ontario includes Southwestern, Central, Golden Horseshoe and Eastern regions. From many questions we’ve received, it seems that often ‘Southern Ontario’ is mistaken for ‘Southwestern Ontario’.

Meanwhile, lake effect snow will create hazardous travel conditions midweek, and this potentially significant winter storm could extend the icy mess into Sunday. Confidence remains low on exact snowfall amounts and ice accumulation, but this system looks like could pack a punch—stay prepared and watch for updates!


📅 Tuesday, March 25, 2025

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📍 Location: Areas east of Lake Huron & Georgian Bay

🌨️ Hazard(s): Snow
📍 Location: Areas east of Lake Huron and Georgian Bay
Timing: Tuesday
⚠️ Impact(s): Hazardous travel conditions, reduced visibility

Confidence: Moderate
Impact: Moderate

🔹 Lake effect snow will develop early Tuesday morning with local snowfall amounts of 5 to 15 cm possible.


📅 Wednesday, March 26, 2025

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📍 Location: Areas east of Lake Huron

🌨️ Hazard(s): Snow
📍 Location: Areas east of Lake Huron
Timing: Wednesday morning
⚠️ Impact(s): Hazardous travel conditions & Reduced visibility

Confidence: Low
Impact Level: Moderate

🔹 The lake effect snow will drift southward Tuesday night into Wednesday morning, with local snowfall amounts of 5 to 15 cm possible. Snow is expected to ease near midday.


⚠️ Friday, March 28, 2025

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📍 Location: Portions of southwestern Ontario and the Greater Golden Horseshoe

🧊 Hazard(s): Ice
📍 Location: Portions of southwestern Ontario and the Greater Golden Horseshoe
Timing: Friday evening
⚠️ Impact(s): Icy surfaces such as roads and walkways

Confidence: Moderate
Impact Level: High

🔹 A prolonged freezing rain event is expected to begin Friday evening, with multiple waves of freezing rain. There is still uncertainty regarding the timing and exact location of the rain/freezing rain boundary. The freezing rain is expected to continue into the weekend for parts of southern, central, and eastern Ontario.


📍 Location: Northeastern, central, and eastern Ontario, as well as eastern portions of the Greater Golden Horseshoe

🌨️ Hazard(s): Snow
📍 Location: Northeastern, central, and eastern Ontario, as well as eastern portions of the Greater Golden Horseshoe
Timing: Friday evening
⚠️ Impact(s): Hazardous travel conditions & snow-covered and slippery roads/walkways

Confidence: Low
Impact Level: Moderate

🔹 Snow will push into the region Friday evening before clearing late Friday night or early Saturday morning. Snowfall amounts remain uncertain.

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📍 Location: Northwestern Ontario and western portions of the North Shore of Lake Superior

🌨️ Hazard(s): Snow
📍 Location: Northwestern Ontario and western portions of the North Shore of Lake Superior
Timing: Friday
⚠️ Impact(s): Hazardous travel conditions & snow-covered and slippery roads/walkways

Confidence: Low
Impact Level: Moderate

🔹 Heavy snowfall is expected Friday morning, persisting through the day before easing Friday evening. The heaviest snowfall areas remain uncertain.


⚠️ Saturday, March 29, 2025

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📍 Location: Most of southern Ontario

Timing: Saturday
🧊 Hazard(s):
Ice
📍 Location: Most of southern Ontario
Timing: Saturday
⚠️ Impact(s):

  • ⚠️ Icy roads and walkways

  • 🌳 Broken tree branches from ice build-up

  • 🔌 Possible utility outages

Confidence: Too low in the extended range to assign a weather threat level
Impact Level: Potentially moderate or greater

🔹 A significant winter storm could bring an extended period of freezing rain, potentially leading to hazardous travel, minor tree damage, and power outages. Stay tuned for updates!


⚠️ Sunday, March 30, 2025

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📍 Location: Most of southern Ontario

🧊 Hazard(s): Ice
📍 Location: Most of southern Ontario
Timing: Sunday
⚠️ Impact(s):

  • ⚠️ Icy roads and walkways

  • 🌳 Broken tree branches from ice build-up

  • 🔌 Possible utility outages

Confidence: Too low in the extended range to assign a weather threat level
Impact Level: Potentially moderate or greater

🔹 A prolonged period of freezing rain is possible. Hazardous travel, tree damage, and power outages could occur. Stay alert for future updates!


Final Thoughts:

A messy mix of snow and freezing rain is set to impact Ontario from Friday through the weekend, bringing travel hazards, icy conditions, and possible power outages. Uncertainty remains in the details but this system has the potential to cause significant impacts—stay tuned for updates!

TLDR; Be prepared for icy conditions, charge your devices, and take caution if you must travel. 🚗💨

Be safe, folks!


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

Spring Storm Looks to Dump Over 10cm of Snow Across Parts of New Brunswick and PEI

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It may be Spring now, but Winter is not giving up without a fight in the Maritimes. Snow will make its return to the region later today and continue into Tuesday morning.

The snow will begin in Western New Brunswick late this afternoon, spreading across the province through the evening. It will also start to snow lightly in Western Nova Scotia in the evening, crossing through to the eastern half of the province and into PEI later in the evening and into the overnight hours.

The snow will be steady and possibly heavy at times across New Brunswick and PEI, which will drive up accumulation totals. The snow, however, will be short-lived in Nova Scotia. After a couple of hours, the snow in Nova Scotia will transition over to rain, with a brief period of ice pellets and freezing rain in between. The majority of the precipitation from this system will end up falling as rain across Nova Scotia, with roughly 10-20mm expected across the province.

The Fundy Coast and both Kings and Queens Counties could see a bit of this mixed precipitation overnight and early Tuesday morning followed by some scattered showers. For the most part, however, both provinces can expect mostly snow over the next 24 hours. The precipitation will start to taper off from west to east during the early morning hours tomorrow and ending across the region by the mid-morning.

Overall, both New Brunswick and PEI can expect over 5cm of snow, with widespread 10-20cm likely across New Brunswick and in Prince County. In Nova Scotia, the transition to rain will limit snowfall totals to less than 5cm, but there is the possibility of more than 5cm falling in the Cape Breton Highlands.

This is just the beginning of what could be an active week for the region and we’re already watching the possibility of another storm hitting late Wednesday.

Spring Snowstorm Could Dump Up to 20cm of Snow on Parts of Southern Ontario to Start the Week

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After an active month of wintry weather across Southern Ontario, March has taken a much calmer turn, bringing spring-like temperatures and even double-digit highs in some areas. However, don’t be fooled by the recent warmth—winter isn’t quite done with us yet. Despite what the calendar says, a surge of colder air will take over for the final days of March, setting the stage for a late-season snowstorm on the horizon.

An organized system is expected to bring heavy snow to parts of Southern Ontario starting late Sunday evening and continuing into Monday. Mixed precipitation will likely limit snowfall accumulation along the Lake Ontario and Lake Erie shorelines. However, further north, particularly around Georgian Bay, lake enhancement could boost totals, with some areas seeing 10-20 cm of snow. This storm could bring the most substantial snowfall in weeks, potentially impacting the Monday morning commute.

In addition to the snow, strong winds will develop on Monday morning and afternoon, with gusts reaching 50 to 70 km/h. This will lead to blowing snow and reduced visibility, especially in areas prone to drifting, such as Grey-Bruce.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The messy weather is set to arrive Sunday evening, with the first bands of precipitation moving into Southwestern Ontario. However, the forecast remains tricky due to overnight warming temperatures. Some areas will start off with wet snow before transitioning to rain, especially near Lake Ontario and Lake Erie.

For Deep Southwestern Ontario, including Windsor, Chatham, Sarnia, and the Niagara region, snowfall will likely be limited as these areas will see mainly rain or a quick changeover from snow to rain after only a few hours. London, Goderich, and Kitchener will see more prolonged snowfall through the overnight hours, though freezing rain and ice pellets may mix in at times.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The heaviest snow is expected to move into Central and Eastern Ontario by the pre-dawn hours of Monday, with several hours of steady snowfall along the leading edge of the system. However, since temperatures will be rising overnight, some of this snow may struggle to accumulate, particularly on road surfaces. Areas near the Lake Ontario shoreline may also see a mix of snow, rain, and ice pellets rather than steady snowfall.

By Monday morning, snow will continue spreading northeast, reaching the Ottawa Valley by sunrise. Given the timing, the snow could create challenging travel conditions during the morning commute, with reduced visibility and slushy roads. School bus cancellations may be possible in rural parts of Central and Eastern Ontario.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

While the widespread snowfall will taper off by late morning or early afternoon, lingering snow is expected around Lake Huron and Georgian Bay, where lake enhancement could lead to heavier localized snowfall. Grey-Bruce, Parry Sound, and North Bay will be among the hardest-hit areas, with additional accumulations into Monday night.

Meanwhile, for Eastern Ontario and the Golden Horseshoe, the bulk of the snow will be finished by midday Monday. However, light lake-effect snow will persist in the snowbelt regions throughout the rest of Monday into Tuesday. Some weak snow squalls could occasionally drift into Eastern Ontario and the Greater Toronto Area (GTA), but accumulation will be minimal outside of the snowbelt zones.

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By the time the system exits Monday evening, the highest snowfall totals will likely be in Bruce Peninsula, northeast Georgian Bay, and Northern Ontario, including Tobermory, Manitoulin Island, Sudbury, Parry Sound, North Bay, and Huntsville. These areas are expected to see 10-20 cm, with locally higher amounts possible.

That said, above-freezing temperatures for several hours on Monday could lead to melting and compacting of the snow, potentially reducing overall accumulations from what falls initially.

For Central Ontario, including Kitchener, Orangeville, Hanover, Owen Sound, Collingwood, Midland, Orillia, Bracebridge, and Bancroft, snowfall totals will generally range between 5-10 cm by Monday evening. However, some areas east of Lake Huron may see slightly higher totals, depending on lake enhancement.

For the Ottawa Valley, Southwestern Ontario, and the Golden Horseshoe away from the lakeshores, accumulations will likely stay under 5 cm. These areas may see a few centimetres of wet snow Sunday night, but overall, nothing significant is expected.

Regions directly along the Lake Ontario and Erie shorelines, as well as Deep Southwestern Ontario, will see little to no snowfall as rain or mixed precipitation will dominate.

Beyond Monday, lake-effect snow will persist into Tuesday, mainly affecting areas around Lake Huron and Georgian Bay, where localized snow squalls could bring a few extra centimetres.

Winter Isn’t Giving up Without a Fight in Parts of Ontario This Week

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Spring may have arrived on the calendar, but winter clearly didn’t get the memo! A late season storm is on the way to remind parts of Ontario that mother nature decides when we’re done with winter. This system will bringing hazardous travel conditions, accumulating snowfall, and blowing snow. Just when you thought it was safe to pack away the snow shovel, winter decides to throw another snowy tantrum to start off the week!


Sunday, March 23, 2025

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Location: North and west of Lake Superior

❄️ Hazard(s): Snow
📍 Location: North and west of Lake Superior
⏳ Timing: Sunday into Monday morning
⚠️ Impact(s): Hazardous travel conditions, reduced visibility, and possible road closures

Confidence: High
📉 Impact: Moderate

A widespread snowfall event will bring accumulations of 15 to 25 cm north and west of Lake Superior. While confidence is high for at least 15 cm, higher terrain areas could see totals closer to 25 cm, though confidence in these higher amounts remains low.

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Location: Northwestern Ontario and north of Lake Superior

❄️ Hazard(s): Snow
📍 Location: Northwestern Ontario and north of Lake Superior
⏳ Timing: Sunday into Monday morning
⚠️ Impact(s): Difficult travel conditions

Confidence: Moderate
📉 Impact: Moderate

Northwestern Ontario and areas northeast toward Lake Nipigon could see 5 to 15 cm of snow. The highest totals, near 10 to 15 cm, are expected close to the Minnesota border and northeastward.


Monday, March 24, 2025

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Location: Northeastern Ontario and parts of southern Ontario

❄️ Hazard(s): Snow
📍 Location: Northeastern Ontario and parts of southern Ontario
⏳ Timing: Monday
⚠️ Impact(s): Difficult travel conditions

Confidence: Moderate
📉 Impact: Moderate

Snow will begin late Sunday night or early Monday morning, with accumulations of 5 to 15 cm expected. However, areas in southern Ontario could see snow transition to rain showers by late morning or early afternoon, creating slushy and messy road conditions. Later in the day, snow will redevelop east of Lake Huron and Georgian Bay.

There is some uncertainty regarding how far south the heavier snow will extend, as the system's track and timing of the changeover to rain remain uncertain.

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Tuesday, March 25, 2025

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Location: Areas east of northern Lake Huron

❄️ Hazard(s): Snow, Blowing Snow
📍 Location: Areas east of northern Lake Huron
⏳ Timing: Tuesday
⚠️ Impact(s): Difficult travel conditions

Confidence: Moderate
📉 Impact: Moderate

Lake effect snow will develop early Tuesday morning, with 5 to 10 cm of snow expected. Gusty winds will create areas of blowing snow, leading to reduced visibility and hazardous travel conditions.

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Final Thoughts:

Winter may be running out of time, but it's making the most of its final days with multiple rounds of accumulating snow and travel impacts. The heaviest snowfall is expected north and west of Lake Superior, with lesser amounts across northwestern and northeastern Ontario. For southern Ontario, uncertainty remains regarding the transition from snow to rain, which could impact accumulation totals.

By Tuesday, lake effect snow and blowing snow east of northern Lake Huron could further worsen travel conditions. Those with travel plans should stay updated on forecasts and prepare for changing road conditions. While spring may be on the calendar, winter isn’t leaving without a fight.

Be safe, folks!


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

The First Day of Spring Won’t Feel Spring-Like in Southern Ontario as Snow Returns on Thursday

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Although we’ve had an early taste of spring across Southern Ontario, the first official day of astronomical spring arrives Thursday morning. But don’t put that shovel away just yet! The mild temperatures we’ve been enjoying are about to be replaced by a surge of colder air over the next 24 hours.

Unfortunately, this means temperatures will drop back into the single digits, and in some cases, below freezing. Along with the cooler temperatures, scattered flurries are expected to develop in parts of Southern Ontario starting Thursday afternoon. While we aren’t anticipating significant accumulation, some areas could see a few slushy centimetres of snow on the roads. This could pose a challenge for those who have switched to summer tires a little too soon.

Looking ahead, it appears this below-seasonal trend will continue through the weekend and into early next week, bringing several chances for snow. Some of these systems could produce notable snowfall accumulation, especially for more northern sections of Central and Eastern Ontario over the weekend.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Right now, a storm system is affecting Northeastern Ontario, with snow expected to continue overnight into Thursday morning. Areas including Sault Ste. Marie, Elliot Lake, and Timmins are on track to see heavy snow, with totals ranging from 20 to 40 cm in the hardest-hit locations.

For the most up-to-date details on the impacts on Northern Ontario, please refer to Environment Canada’s latest alerts by downloading our free weather app here.

Meanwhile, over Southern Ontario, a weakening line of thunderstorms is expected to push through during the pre-dawn hours of Thursday. When you wake up, it may still feel like spring, with temperatures near double digits in the morning. However, don’t be fooled—a sharp drop in temperatures is expected later in the day. If you’re heading out, it’s definitely a day to layer up!

Rainfall amounts will likely be fairly insignificant, with around 5 to 10 mm expected. However, localized areas could see higher amounts if they experience heavier thunderstorms.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

By Thursday afternoon, cold air will begin filtering into western sections of Southern Ontario, leading to a rain-to-snow transition starting as early as 1 to 3 PM for regions near Lake Huron and Georgian Bay.

With temperatures dropping close to the freezing mark and residual moisture from earlier rainfall, icy conditions could develop on untreated surfaces. While it doesn’t look like a true flash freeze, it could still result in hazardous travel conditions Thursday evening and into the overnight hours.

The snow is expected to persist into the evening, with the heaviest precipitation focused on Southwestern and Central Ontario. Areas in Eastern Ontario and around the Golden Horseshoe will likely avoid the transition to snow, as temperatures won’t drop enough before the precipitation exits.

temperature - MAP FROM WEATHERBELL

Friday, the first full day of spring, will start on a chilly note, with most of Southern Ontario waking up to temperatures at or slightly below freezing. This also means a risk of frost, so if you’ve started gardening early, you may want to bring in or cover any sensitive plants.

Factoring in the wind chill, some parts of Central and Eastern Ontario could experience feels-like temperatures in the -10s—a sharp contrast to the 20°C+ highs that many regions enjoyed on Wednesday!

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Despite this blast of colder air, we aren’t expecting significant snowfall accumulation on Thursday, especially compared to what Grey-Bruce and Muskoka have endured this winter.

However, there could still be some travel impacts, with 2 to 4 cm possible in areas including Kincardine, Hanover, Owen Sound, Wiarton, Tobermory, Parry Sound, Huntsville, Sundridge, and North Bay. Due to wet surfaces from earlier rain, some of this snow may melt on contact, leading to lower actual snowfall totals.

Elsewhere across Southwestern Ontario, Central Ontario, and the Ottawa Valley, a few flurries could fall Thursday afternoon into the evening, but accumulation will be minimal—at most 2 cm, and in many cases, it may not even stick to the ground.

This won’t be our last chance for snow in the coming days. We are closely monitoring a weak system that could bring a few centimeters of snow to Southern Ontario on Saturday.

Another system, arriving Sunday night into Monday, could be more significant. Early model data suggests it may bring over 10 cm of snow to parts of the region. However, the exact snowfall amounts will depend on the storm’s track, as it also appears to include freezing rain and mixed precipitation. We’ll be watching this closely and will have more details as we get closer.

First Isolated Severe Thunderstorm Risk of the Season for Parts of Southern Ontario Sunday Afternoon and Evening

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It’s certainly been a while since we’ve had an isolated risk for severe thunderstorm activity in Southern Ontario, but here we are! Welcome to Spring! What we’re expecting is a line of thunderstorms and based on the time I’m writing this (11:11am), it looks like it has already begun to develop over Lake Erie. This line will continue to push to the northeast, affecting the Niagara Region and potentially all the way up to Barrie and parts of Simcoe County.

RADAR IMAGE FROM 11:12 AM EDT - MAP FROM INSTANTWEATHER PRO

Taking a look at the IW Pro app screenshot above, you can see the thunderstorm line beginning to develop over Lake Erie. We’re expecting nickel-size hail (perhaps a bit larger), strong wind gusts, torrential rain and frequent lightning with this line. Additionally, you can see a red outline of a Tornado Watch south of the border that covers areas south of Lake Erie.

An isolated tornado cannot be entirely ruled out with this system slipping past the international border and tracking into Ontario, so we’ll be keeping a very close eye on radar today. If you don’t already have our free app, InstantWeather, today may be a good day to download it so we can notify you of any rotating storms, funnel cloud reports or Environment Canada alerts.

Some models have also shown some very intense wind gusts, potentially exceeding 100km/h, especially in eastern Ontario, so we’re fairly concerned with that potential. Being an early season event, we decided to go with a Marginal (green) risk, but there certainly is a chance these storms could exceed the Slight (yellow) threshold, especially with the wind risk.

MAX WIND GUST FORECAST FROM THE HRRR MODEL - MAP FROM WEATHERBELL

In the image above, we see the HRRR model’s maximum wind gust forecast for Southern Ontario, showing some very strong winds in yellow and orange. This is just one model’s output so it’s not a guarantee. Nonetheless, if wind gusts do reach these levels, even in isolated areas, we could end up seeing some fairly strong wind damage to trees, hydro polls or perhaps even structures.

The main risk, timing wise, should begin this afternoon in the Niagara Region, with storms moving northeast from Lake Erie and that risk should continue to spread northeast into the evening hours. Generally, our main concern is for Niagara and areas north and east of Lake Ontario into eastern Ontario. However, we have highlighted parts of Southwestern Ontario, the GTHA, and Central Ontario as well, as we’ve seen some model data suggesting strong wind gusts are possible in those regions, along with hail, torrential rain, isolated flooding, frequent lightning and a small risk of an isolated tornado.

In general, the tornado risk is quite isolated. Having said that, with a potent system south of the border, there is always a chance we could see some tornado activity sneak into Ontario and based on some of the model data we’ve seen over the past couple of days, the risk of a spin-up or two cannot be ruled out.

We do plan on doing a livestream if storms continue to look strong this afternoon and evening so make sure to subscribe to our YouTube channel in order to get notified if and when we go live!

We’ll be posting more updates to our social media pages as well so if you’re on Facebook, you can find us at Ontario Storm Watch. We also have a fantastic storm reporting group on FB with Ontario Storm Reports. And if you’re on X/Twitter, you can find us at @IWeatherON.

More details ASAP and stay safe today, folks!

- Adam

Mid-March Snowfall Will Help Build Back Some Snowpack With 10-20cm Expected Across a Wide Stretch of Alberta & Saskatchewan

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While we’re a little over a week away from the official start of spring, a majority of the snowpack is already gone across parts of Alberta and Saskatchewan. However, winter is still hanging on with more snow incoming over the next couple of days.

This will help to add some much-needed moisture to part of the region, especially since we have seen well below average snowfall since November. Unfortunately for Southern Alberta, the driest part of the Prairies, can expect little to none of this incoming moisture.

The snow will cross through the Rockies and into Alberta at around sunrise on Thursday and spread northeastward deeper into the province throughout the morning and into the afternoon. The snow will intensify starting in the early afternoon and this heavier snowfall will continue straight through overnight. This will lead to a large stretch of Central and Northern Alberta receiving 10-20cm of snow and up to 25cm possible to the north of Lake La Biche and Cold Lake through Friday morning.

Model Image showing the location and intensity of snow (Blue) and Rain (Green) at 4PM MT on Thursday

Light snow will make its way into Northern Saskatchewan early Thursday afternoon, followed by the more intense snowfall beginning in the early evening. This area of heavier snow will cross through Saskatchewan in an almost due easterly path and similar to in Alberta, it will dump 10-20cm across a large stretch of the province and up to 30cm from the Alberta border to almost La Ronge by Friday afternoon.

The arrival of additional moisture from a separate low-pressure system in the US on Friday morning makes the forecast in Central and Southern Saskatchewan a bit more complicated. This appears to be bringing a combination of rain, freezing rain, ice pellets, and snow to most of the southern half of the province throughout the morning as it merges with the system from the west.

There is still some uncertainty regarding the precipitation type and the area that could be impacted by the arrival of the secondary system. Therefore, for this forecast, we are only focusing on the snow coming from Alberta and we will cover this additional precipitation in a separate forecast that will be issued later in the day on Thursday

Model Image showing the location and intensity of snow (Blue), Rain (Green), Freezing rain (pink), and ice pellets (orange) at 2aM MT on Friday

More Freezing Rain & Snow in Store, Potential for Flash Freeze Across the Maritimes on Friday

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The moisture-laden Colorado Low that has brought a mixed bag of precipitation to the Maritimes over the past two days appears to have one last trick up its sleeve. Cold air will flood into the region overnight, transitioning the rain over to snow and bringing some further complications.

In New Brunswick, the rain will start to switch over at around 1-2AM, however there will be a couple of hours of freezing rain in Central and Northern New Brunswick once again before the change over to snow. The heaviest snow is expected to fall in Carleton and Victoria Counties and northward into Madawaska and parts of Restigouche. This region can expect 10-20cm of snow by Saturday morning and the possibility of locally higher amounts, particularly in Madawaska County. Much of the rest of the province will see 5-10cm, with the exception of along the Fundy Coast and into the Southeast and Moncton area, where less than 5cm is anticipated.

Model Image showing the location and intensity of snow (Blue), Rain (Green), Freezing rain (Pink), and Ice pellets (Orange) at 5AM AT Friday

In Western Nova Scotia, the rain will taper off in the early morning hours of Friday, but it will be replaced by snow starting at around 8-9AM. The snow will be light and short-lived for much of the western half of the Mainland, but it will remain fairly steady in the Annapolis Valley through the afternoon and into the evening, leading to 5-10cm by the end of the day.

Across the rest of Mainland Nova Scotia, snowfall will be light and scattered as the band of snow makes its way across the province, leading to up to 5cm. The snow will eventually begin in Cape Breton late Friday evening, where it will continue through to Saturday morning. Most of the Island can expect 5-10cm, with lesser amounts around Sydney and up to 20cm in the Highlands.

The snow in Prince Edward Island, like in most of Nova Scotia, will also be very light and patchy. It will reach the province in the evening and the scattered flurries will continue into Saturday morning, leading to up to 5cm across the Island.

Modelled Temperatures at 9PM Thursday

Modelled Temperatures at 1PM Friday

The drop in temperatures that will cause the transition from rain to snow has another considerable implication. Temperatures are expected to plummet to several degrees below freezing across the region, after climbing into the double digits Thursday, and when combined with the preceding rain and melt-water, most of the Maritimes is under the threat of a flash freeze occurring on Friday.

This potential flash freeze could lead to wet, untreated surfaces quickly becoming icy and making travel hazardous as the temperatures drop across the region. Adding a layer of snow on top of this ice will keep things quite slippery as well.

The winds are expected to pick up on Friday, gusting up to 70km/h through most of the afternoon and then as high as 100km/h beginning in the evening and continuing for most of Saturday. These strong winds will likely reduce visibility due to blowing snow, both during and after the snow has stopped falling, and possibly lead to localized power outages.

Icy Mix, Flash Freeze and Strong Winds Could Bring Travel Disruptions to Ontario on Thursday

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Thursday, March 6, 2025: Winter Weather Hazards For Parts of Ontario

Environment Canada is forecasting a mix of snow, strong winds, and rapidly dropping temperatures for Thursday. Rain will transition to snow across much of the province, with accumulations of 5 to 10 cm expected in several areas. Strong northwest winds could reach up to 80 km/h, leading to widespread blowing snow and dangerous travel conditions, especially southeast of Lake Huron and Georgian Bay. Additionally, a sharp temperature drop will cause any standing water or wet surfaces to freeze quickly, creating hazardous icy conditions. Eastern Ontario and the Greater Golden Horseshoe will see a heightened risk of ice as rain transitions to freezing conditions throughout the day. Travelers should prepare for difficult driving conditions, reduced visibility, and potential road closures. Stay updated on this evolving system as details continue to develop.

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Location: Portions of central Ontario and southern portions of northeastern Ontario

  • Hazard(s): Snow, Blowing Snow, and Ice

  • Timing: Thursday

  • Impact(s): Difficult travel conditions, reduced visibility, and possible road closures.

  • Confidence: High

  • Impact Level: Moderate

Rain will transition to snow early Thursday morning, with snowfall accumulations of 5 to 10 cm expected. Alongside this snowfall, gusty northwest winds will lead to blowing snow in exposed areas. A sharp temperature drop will cause any standing water or wet surfaces to freeze quickly, creating hazardous icy conditions Thursday morning.

Location: Areas southeast of Lake Huron and Georgian Bay

  • Hazard(s): Snow, Blowing Snow, Wind, and Ice

  • Timing: Thursday

  • Impact(s): Difficult travel conditions, reduced visibility, possible road closures, and potential power outages.

  • Confidence: Moderate

  • Impact Level: High

Rain will transition to snow overnight or early Thursday morning, with 5 to 10 cm of accumulation possible. Strong northwest winds up to 80 km/h are expected, causing widespread blowing snow and dangerous whiteout conditions. The sharp temperature drop will also lead to ice formation as wet surfaces quickly freeze Thursday morning.

Location: Portions of eastern Ontario and the Greater Golden Horseshoe

  • Hazard(s): Ice

  • Timing: Thursday

  • Impact(s): Difficult travel conditions due to rapid freezing and ice buildup.

  • Confidence: Moderate

  • Impact Level: Moderate

    Rain will transition to snow Thursday morning or afternoon, accompanied by a sharp drop in temperature. Any standing water or wet surfaces are expected to freeze quickly throughout the day, leading to slick and icy conditions on roads and sidewalks.

Location: Portions of southwestern Ontario and areas northeast of Lake Erie and Lake Ontario

  • Hazard(s): Snow, blowing snow, wind, and ice

  • Timing: Thursday

  • Impact(s): Difficult travel conditions, reduced visibility, and possible road closures. Possible power outages.

  • Confidence: Moderate

  • Impact Level: Moderate

Rain will transition to snow overnight or early Thursday morning, with snowfall accumulations of 2 to 4 cm expected. Strong west or southwest winds, potentially reaching 80 km/h, may cause blowing snow in exposed areas, further reducing visibility. A sharp temperature drop will also lead to icy conditions as standing water or wet surfaces freeze rapidly Thursday morning. Travelers should prepare for hazardous road conditions and potential disruptions.


Friday, March 7, 2025: Snow Squalls & Blowing Snow

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Location: Southeast of Lake Superior, Lake Huron, and Georgian Bay

  • Hazard(s): Snow and blowing snow

  • Timing: Beginning Thursday evening and continuing through Friday

  • Impact(s): Possible difficult travel conditions

  • Confidence: Moderate

  • Impact: Moderate

Lake effect snow is expected to develop Thursday night and persist through Friday, bringing total snowfall amounts of 5 to 10 cm. Gusty winds may lead to areas of blowing snow, particularly in exposed locations, reducing visibility and making travel hazardous. Drivers should prepare for changing road conditions and potential delays.


Final Thoughts:

As this storm system moves through, travel across parts of Ontario will become increasingly difficult on Thursday due to a combination of snow, blowing snow, strong winds, and icy conditions. The transition from rain to snow, along with a sharp temperature drop, will create hazardous roads as wet surfaces quickly freeze. Power outages are also a concern in areas experiencing stronger winds, particularly near Lake Erie and Lake Ontario.

Lake effect snow will add to the challenges on Friday, especially southeast of Lake Superior, Lake Huron, and Georgian Bay, where accumulating snowfall and blowing snow could lead to reduced visibility and treacherous driving conditions. While uncertainty remains regarding exact snowfall totals, the potential for rapid changes in weather conditions warrants extra caution.

If you must travel, plan ahead, check road conditions frequently, and be prepared for sudden deteriorations. Stay tuned for updates as this system develops.

Be safe, folks!


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

Threat of Localized Flooding & Freezing Rain Risk in New Brunswick with the Arrival of a Winter Storm Wednesday

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A Colorado Low is set to move through the Maritimes this week, bringing a mixture of rain, freezing rain, and snow to the region, along with the risk of flooding as temperatures rise.

Brief light snow will begin in Southwestern New Brunswick at around sunrise on Wednesday, spreading northeastward into the province throughout the morning and early afternoon. There is a chance for some freezing drizzle around Saint John mixed with the snow. Meanwhile in Nova Scotia, the precipitation will fall as rain across much of the western half of the province, aside from some light snow expected in Northern Nova Scotia.

Model Image showing the location and intensity of snow (Blue), Rain (Green), Freezing rain (Pink), and Ice pellets (Orange) at 1PM AT Wednesday

By the mid-afternoon, the bulk of the moisture from the system will push eastward into the region, bringing rain to Nova Scotia and Southern New Brunswick while Central and Northern New Brunswick will start to receive snow. The precipitation will reach PEI later in the afternoon as a mix of rain and snow across the Island.

Model Image showing the location and intensity of snow (Blue), Rain (Green), Freezing rain (Pink), and Ice pellets (Orange) at 12AM AT Thursday

Starting in the evening, the warm air and rain will start to push northward, leading to a transition from snow to a few hours of freezing rain across Central and Northern New Brunswick, as well as into PEI and Cape Breton. The freezing rain will continue overnight and into early Thursday morning. Ice accretions of up to 5mm are likely, but buildup will be short-lived as the temperatures will continue to rise and the freezing rain will switch over to rain for the remainder of Thursday.

Ahead of the transition to freezing rain and rain, up to 10cm of snow will fall, with the highest amounts expected in Retigouche County and into the Acadian Peninsula.

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Not only will the fresh snowfall melt with the rain and temperatures climbing into the double digits on Thursday, but a considerable amount of pre-existing snowpack, especially across New Brunswick will also melt. Parts of Central and Northern New Brunswick have over 70cm of snow on the ground as of Tuesday evening and that value is expected to drop to below 50cm in some areas by Friday. Similarly, Moncton and Saint John, where 10-20cm is already on the ground, could see most, if not all, of their snow melt.

This rapid melting of the snow, along with some heavy rain expected later in the day on Thursday, has led to a significant flooding threat across New Brunswick. The ground is still frozen and recent frigid temperatures have led to ice buildup on lakes and rivers, which will limit where the water from the snow melt and rain can go.

The situation in Nova Scotia and into PEI is less widespread with lesser snowpack overall. There are some areas in Nova Scotia that have up to 30cm of snow on the ground that will almost completely melt, namely in the Annapolis Valley and in Cumberland and Colchester Counties. Those in Cape Breton can expect to see some of their snowpack melt, but the Highlands will experience very little change. In Prince Edward Island, on the other hand, next to no snow will remain on the Island come Friday aside from pockets of up to 5cm possibly remaining in Prince and/or Kings Counties.

The modelled depth of snow across Atlantic Canada, in centimetres, as of 8pm Tuesday.

Flooding Risk & Heavy Snow Possible Wednesday For Parts of Ontario Says Environment Canada's Forecast

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A Colorado Low is expected to bring a mix of rain and snow to Ontario on Wednesday, potentially leading to flooding concerns in some areas and hazardous winter weather in others. The exact track of this system remains uncertain, and future updates may bring changes to precipitation amounts and affected areas. Here’s what Environment Canada has mentioned in their forecast:


Southern Ontario: Flooding Risk for Tuesday night - Wednesday, March 5:

Hazard: Rain
Location: East of Lake Huron, central Ontario, and portions of northeastern Ontario
Timing: Tuesday night through Wednesday
Impact: Potential flooding in low-lying areas and possible washouts near rivers, creeks, and culverts.
Confidence: Low
Impact: High

A strong system moving into the province could bring significant rainfall to these regions. The combination of heavy rain and rapid snowmelt in areas with a deep snowpack could lead to localized flooding issues. The exact track of the system remains uncertain, so be sure to stay updated as new information becomes available.

Hazard: Rain
Location: Southwestern, eastern Ontario, and the Golden Horseshoe
Timing: Tuesday night through Wednesday
Impact: Possible flooding in low-lying areas.
Confidence: Low
Impact: Moderate

Rainfall from the same system could cause flooding concerns in urban areas and places with poor drainage. While the overall flood risk is lower than in central and northeastern Ontario, localized issues remain possible due to snowmelt and prolonged rainfall.


Northeastern Ontario: Heavy Snow Possible Wednesday, March 5:

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Environment Canada’s forecast:

Hazard:
Snow
Location: Northeastern Ontario and areas north of Lake Superior
Timing: Wednesday
Impact: Difficult travel conditions, reduced visibility, and possible road closures.
Confidence: Low
Impact: High

While some areas receive heavy rain, northern Ontario will likely see significant snowfall, which could lead to hazardous travel conditions. The heaviest snow is expected in areas north of Lake Superior, but the exact placement of the heaviest bands will depend on the storm’s final track.


Final Thoughts:

There remains significant uncertainty regarding the exact storm track, precipitation types, and total amounts. Future updates may adjust the areas of concern and the severity of the impacts. Residents in flood-prone areas should monitor conditions closely and be prepared for potential flooding. Those in Northeastern Ontario should prepare for heavy snowfall and difficult travel conditions. Stay tuned for further updates as more details become available.


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

Winter Returns to Ontario as End of Week Clipper Brings Widespread 10-20cm of Snow for the Start of March

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The first half of February has been nothing short of active across Ontario, with what felt like an endless stream of snowstorms dumping significant amounts of snow across many areas.

Fortunately, the latter half of the month provided a much-needed break from the active weather pattern. Milder temperatures pushed daytime highs above the freezing mark, leading to a steady melt of the extensive snowpack that had built up over previous weeks.

However, as the saying goes, all good things must come to an end. As we flip the calendar to March, active weather is set to make a comeback. A strong Alberta Clipper is on track to sweep across Northern and Southern Ontario on Friday, bringing widespread snowfall totals of 10 to 20 cm by Saturday.

In addition to the snow, this system will usher in much colder temperatures for the weekend. Wind chills are expected to drop into the -20s across Southern Ontario, while Northern Ontario will see even more bitter conditions, with wind chills dipping into the -30s. This will feel like a drastic change compared to the mild temperatures earlier this week, when parts of Southern Ontario saw highs in the mid to upper single digits.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The first signs of the approaching clipper will be felt in Northwestern Ontario late Thursday night into early Friday morning, as snow spreads in from Central Manitoba.

Locations like Kenora, Dryden, and Thunder Bay will be the first to see snowfall, beginning around midnight and continuing into the early morning hours.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

As the system moves eastward, snow will taper off across Northwestern Ontario by late Friday morning, while the heaviest snowfall shifts to Northeastern Ontario, particularly around Lake Superior and Georgian Bay.

By this time, we’ll also begin to see light snow entering Southwestern Ontario, particularly around Lake Huron, which will become more widespread as the day progresses.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By Friday afternoon, snow will spread into Southern Ontario, becoming more steady across the Greater Toronto Area (GTA).

The heaviest accumulations will likely be concentrated along the Lake Huron and Georgian Bay shorelines, particularly in Grey-Bruce, Muskoka, and Parry Sound. Lake enhancement in these areas could provide an extra boost to snowfall totals.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The worst conditions for Southern Ontario will occur Friday evening, when snowfall rates could reach 2 to 4 cm per hour in the most intense bands. The snow will be widespread, impacting Central and Eastern Ontario, the GTA, and Grey-Bruce.

Additionally, blowing snow may become a significant issue, as wind gusts of 40 to 70 km/h could reduce visibility on the roads.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By midnight, snowfall intensity will begin to gradually diminish, and most areas southwest of Lake Simcoe—including the GTA—should see snow tapering off. However, lake-effect snow east of Lake Huron may continue into the overnight hours.

Meanwhile, light snow will persist overnight across Central and Eastern Ontario, but it is expected to slowly taper off by Saturday morning.

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In terms of Alberta Clippers, this one appears to be on the stronger side, with a fair amount of moisture to work with. While it will be fast-moving, we are still expecting widespread snowfall totals between 10 to 20 cm across much of Central and Eastern Ontario by Saturday morning.

Some areas could overachieve, with up to 25 cm possible, especially in regions east of Georgian Bay, where lake enhancement could further boost totals.

Further south, including areas like Goderich, Kitchener, Toronto, Peterborough, and Kingston, lower snowfall amounts are expected. While these regions will still see fresh snow, totals will likely range between 5 to 10 cm due to lower snowfall rates compared to areas further north.

For Deep Southwestern Ontario, including London and the Niagara region, snowfall will be minimal, with less than 5 cm expected.

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Across Northern Ontario, a wide swath of the region is on track to receive 10 to 20 cm from this system, including Dryden, Thunder Bay, Sault Ste. Marie, Timmins, Sudbury, and North Bay.

As with the south, there is potential for some areas to overperform, particularly east of Lake Superior, where localized totals of up to 25 cm are possible.

With accumulating snow, strong winds, and plummeting temperatures, this clipper will bring notable impacts heading into the weekend. Stay tuned for further updates as the system approaches!

Quick Blast of Intense Snowfall Could Bring Over 20cm to Parts of Saskatchewan and Manitoba

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February has been a quiet month across the Prairies, as far as active weather is concerned. That has changed though, with the arrival of warmer air in the past few days, which has also brought heavier snowfall back to the region. Now, we are looking at that heavy snow across Saskatchewan and Manitoba for Thursday and Friday.

The snow will begin early Thursday in Northern Saskatchewan and surge southeastward throughout most of the morning, crossing into Manitoba at around 8-9am. The snow will be steady and fairly light for most of the day, falling at up to 2cm/hr, leading to a large swath of over 10cm across both provinces.

In the late afternoon and early evening, the snow will begin to taper off in Saskatchewan while at the same time, intensifying in Central Manitoba. The heavier snow is expected to cross the province throughout the evening and will bring snowfall totals to the higher end of the 10-20cm range, with a strong likelihood of localized pockets of over 20cm, particularly around Flin Flon, The Pas and Norway House. The intensified snowfall will also be associated with some stronger wind gusts of up to 70km/h, which could result in isolated whiteouts due to blowing snow.

As the short-lived system exits the region, the snow will finally taper off in Saskatchewan shortly after midnight on Friday and in Manitoba just before sunrise. The winds are also expected to weaken Friday morning, therefore reducing the blowing snow risk.

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

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

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

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

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

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

Projected Snowfall Totals:

  • Localized amounts near 100 cm are possible in Grey-Bruce, with hotspots likely near Port Elgin, Hanover, Chatsworth, and Flesherton. Not everyone in this zone will see these totals, but some areas will get buried.

  • 25 to 50 cm is likely across the rest of Grey and Bruce counties, extending into northern Huron and Perth counties. This also includes areas along the southeastern shoreline of Georgian Bay, such as Collingwood, Wasaga Beach, and Barrie.

  • 5 to 15 cm could extend into Kitchener, Guelph, Durham, and York as occasional bursts of heavy snow push outside the core snowbelt region.

  • The GTA may see light snow at times but is unlikely to receive more than 5 cm over the next two days.

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

Stay safe and stay warm!

Strongest Snowstorm in Years to Bury Southern Ontario in Up to 50cm of Snow on Sunday

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Brace yourself, Southern Ontario! One of the biggest snowfalls in recent years is on the horizon for many parts of the region—excluding the usual snowbelt areas. This includes major cities like Toronto, Kingston, and Ottawa, which have largely dodged significant snowstorms over the past few years due to milder winters.

That streak ended earlier this week with the first storm in this parade of systems, dropping a widespread 20 cm or more across Southern Ontario. However, that system could pale in comparison to what’s coming next. This stronger storm is likely to bring 30 cm or more to a large portion of the region throughout Sunday.

As of Saturday afternoon, the first round of snow has already arrived, bringing steady snowfall from Southwestern Ontario into the Golden Horseshoe. This initial wave will be just the beginning, with up to 10 to 15 cm expected by the end of the day.

The second and much more intense round of precipitation will begin early Sunday morning as the system taps into tropical Gulf moisture and directs it straight into the Great Lakes region.

By morning and into the afternoon, conditions will deteriorate rapidly, with snowfall rates reaching 4 to 8 cm per hour. When combined with moderately strong wind gusts, this will lead to widespread blowing snow, significantly reduced visibility, and even localized blizzard conditions.

By the time the snow begins to taper off late Sunday, widespread totals of 30 to 50 cm are expected across Central and Eastern Ontario, extending into the Greater Toronto Area. The hardest-hit areas could even exceed 50 cm, particularly in Eastern Ontario, where elevation may enhance accumulation. Meanwhile, locations along the Lake Erie shoreline, including Windsor, Niagara, and Chatham, may see lower snowfall totals due to potential mixing with freezing rain or ice pellets.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

The first round of snow will continue steadily across Southern Ontario through Saturday evening and past midnight, with heavier snowfall targeting the Golden Horseshoe and the southern portions of Central and Eastern Ontario.

At the same time, the second round of snow will be rapidly developing south of the Great Lakes, forming over Indiana, Kentucky, and Ohio. This storm will strengthen quickly as it begins pulling in moisture from the Gulf of Mexico, which is also fueling severe thunderstorms across the southern U.S.

While there may be a brief lull overnight, don’t let it fool you—the worst is still ahead. The heaviest snowfall will begin to push into Southwestern Ontario before sunrise, bringing a rapid increase in snowfall rates from 1 to 2 cm per hour earlier in the night to 2 to 4 cm per hour by the early morning.

As the system intensifies, hourly rates of 4 to 6 cm—potentially even higher in the strongest bands—are expected. Road conditions will deteriorate quickly, with significantly reduced visibility and heavy blowing snow making travel extremely hazardous.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Most areas will remain on the snowy side of this system, but there is some uncertainty regarding how far north a warm layer could push. This could lead to a brief period of ice pellets or freezing rain in areas along the Lake Erie shoreline, including Windsor, Leamington, Chatham, St. Thomas, Tillsonburg, Hamilton, and Niagara Falls.

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While significant freezing rain is not expected, some minor ice accretion of a few millimetres could occur, particularly right along the shoreline.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

By early to mid-morning Sunday, the storm’s intensity will peak across Southwestern Ontario and the GTA, with snowfall rates reaching 4 to 6 cm per hour in many areas. In the strongest bands, these rates could climb even higher, creating whiteout conditions.

Wind gusts of 40 to 60 km/h will further reduce visibility, and there is even the possibility of thundersnow as some of these snow bands intensify.

Meanwhile, areas farther north, including regions around Lake Simcoe, Peterborough, and into the Ottawa Valley, will begin to see snowfall intensities climb to 1 to 2 cm per hour, eventually reaching 5 to 10 cm per hour by the early afternoon

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The later part of Sunday morning after sunrise will see the worst conditions through Southwestern Ontario into the GTA as snowfall rates increase even further towards 4 to 6cm and possibility even higher in the strongest pockets of snow.

This snow will also be accompanied by increasing wind gusts near 40 to 60 km/h leading to blowing snow and blizzard conditions. Don’t be surprised to see some thundersnow during the morning as these bands of snow will be quite strong and could produce some lightning as they move through the region.

Snowfall intensity will also gradually increase through Central and Eastern Ontario with hourly snowfall rates reaching 1-2cm per hour around Lake Simcoe through Peterbough and into the Ottawa Valley.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

As the system continues to push eastward, the most intense snowfall rates will shift into Central and Eastern Ontario. This is when travel will become nearly impossible in these areas as plows struggle to keep up with the rapid accumulation.

For Southwestern Ontario and the GTA, conditions will begin to improve slightly in the afternoon as the heaviest snow moves east. However, steady snowfall of 1 to 3 cm per hour will continue through much of the afternoon, with strong winds still blowing around earlier accumulations and keeping visibility low.

Snow will gradually taper off across Central and Eastern Ontario by Sunday evening, but blowing snow will remain a significant issue overnight. Travel will remain difficult even after the snowfall ends, particularly in areas with open terrain where drifting will be an issue.

By Monday, conditions should improve, but significantly colder air will move in. If possible, clearing snow on Sunday before temperatures drop is strongly recommended, as the snow will become much heavier to shovel once it settles and freezes.

ESTIMATED WIND GUSTS - MAP FROM WEATHERBELL

The strongest wind gusts will be found in Eastern Ontario, peaking during the early to mid-afternoon. Widespread gusts of 50 to 70 km/h are expected, with some areas, particularly around Ottawa and to the east, possibly seeing gusts near 80 km/h.

In comparison, the rest of Southern Ontario, including the Golden Horseshoe, will experience gusts of 40 to 60 km/h, while Southwestern Ontario will likely see gusts under 40 km/h.

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These wind speeds combined with the extreme snowfall rates expected across Eastern Ontario will almost certainly lead to blizzard conditions.

For a storm to meet the official criteria for a blizzard, winds of 40 km/h or greater must cause widespread reductions in visibility to 400 meters or less due to blowing and falling snow for at least four consecutive hours.

Based on current model data, it is highly likely that visibility will remain near zero for at least six hours from late morning to early/mid-afternoon in many parts of Eastern Ontario, surpassing the official blizzard threshold.

While it remains uncertain whether areas such as the GTA, Lake Simcoe, and Muskoka will officially reach blizzard criteria, blowing snow will still cause significant travel disruptions regardless of classification.

Regardless of whether your area officially meets blizzard criteria, this storm will create extremely dangerous travel conditions across much of Southern Ontario throughout Sunday.

Roads will become impassable at times, and even major highways will be difficult to navigate. Plows will struggle to keep up with the rapid accumulation, making travel nearly impossible in the worst-hit areas. If you don’t absolutely need to be on the roads, it is strongly advised to stay home.

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By the time the storm ends, the highest snowfall totals will be found across Central and Eastern Ontario, extending into portions of the GTA, with widespread accumulations ranging from 30 to 50 cm. Some areas, particularly in Eastern Ontario near Ottawa and through higher elevations to the west, could exceed 50 cm.

Regions around Lake Simcoe and the northern GTA will likely end up with 30 to 40 cm, though locally higher amounts are possible in areas such as the Dundalk Highlands. The Hamilton region and western GTA may see slightly lower totals, around 20 to 30 cm, due to the potential for ice pellets mixing in at times.

Southwestern Ontario, particularly along the Lake Huron shoreline, will see slightly less snowfall, with totals ranging from 20 to 30 cm. This includes areas such as Sarnia, London, Goderich, Grey-Bruce, Parry Sound, and North Bay. However, if the system strengthens earlier than expected, some of these locations could still exceed 30 cm.

Meanwhile, the lowest totals will be found along the Lake Erie shoreline, including Windsor, Chatham, and the Niagara region, where snowfall will range from 10 to 20 cm.

Looking ahead, colder temperatures are expected to settle into Southern Ontario by Monday. It would be wise to clear as much snow as possible on Sunday before the deep freeze sets in, as the snow will become significantly harder to move once temperatures drop.

Additionally, this colder air may trigger a resurgence of lake-effect snow early next week, which could lead to further significant snowfall accumulations in the typical snowbelt regions around Lake Huron and Georgian Bay. More details on that will come in a separate forecast.

This storm will be a major event, and conditions will be dangerous. If possible, stay home and avoid travel. We will continue to monitor the latest data and provide updates as needed. Stay safe!

Intense Snowstorm Could Bring Blizzard Conditions and Up to 30-60cm of Snow to Southern Ontario This Weekend

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The snowy weather isn’t letting up as yet another winter storm takes aim at Southern Ontario over the Family Day long weekend. This system will arrive in multiple waves, beginning Saturday and continuing through Sunday. By the time it moves out late Sunday, much of Southern Ontario could be buried under as much as 60 cm of snow.

Strong winds will develop throughout Sunday morning into the afternoon, with gusts reaching 50 to 80 km/h in some areas. These powerful winds, combined with heavy snowfall, will create dangerous whiteout conditions and may even reach blizzard criteria. Travel is expected to become difficult as early as Saturday morning, with conditions steadily worsening through the night and into Sunday.

The most hazardous conditions are expected Sunday morning and afternoon, as intense snowfall rates are combined with strong wind gusts, making all non-essential travel extremely dangerous. Highway closures are highly likely in the hardest-hit regions as plows struggle to keep up with rapid snowfall rates, while blowing and drifting snow significantly reduces visibility.

There is still some uncertainty regarding the storm's exact track, which will determine where the heaviest snowfall occurs. Areas along the Lake Erie shoreline and possibly parts of the Golden Horseshoe could see periods of freezing rain or ice pellets by late Sunday morning. While this would create its own hazards, any mixing would also lower overall snowfall totals.

As of now, Eastern and parts of Central Ontario appear to be in line for the highest snowfall amounts. Combined two-day snowfall totals could range from 30 to 60 cm by Sunday night, with 5-10 cm expected on Saturday and an additional 25-50 cm possible on Sunday.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

The storm will get underway Saturday morning as steady snow moves into Deep Southwestern Ontario from Michigan. It will spread into London and the Greater Toronto Area (GTA) by late morning. Some light flurries may reach Central and Eastern Ontario, but the more persistent snowfall will remain south of Lake Simcoe.

At this stage, conditions may not seem too severe, leading to the false impression that the storm has been overhyped. However, don’t be fooled—snowfall rates will gradually increase through the afternoon, reaching 1-2 cm per hour and steadily accumulating.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

By mid-afternoon Saturday, light to moderate snowfall will have spread across most of Southern Ontario. The heaviest snowfall will be concentrated over Southwestern Ontario and the GTA, while Central and Eastern Ontario, including the Ottawa Valley, may only see scattered flurries.

There are indications that parts of Deep Southwestern Ontario—including Windsor, Chatham, and possibly London—may see a transition to ice pellets or freezing rain. Meanwhile, Kitchener, Hamilton, and the GTA should remain primarily snow.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

Heading into the evening, the storm’s moisture supply will intensify as it taps into the Gulf of Mexico, keeping snow steady across Southern Ontario. However, Central and Eastern Ontario may experience more scattered snowfall during this time. The most persistent snow bands are expected to set up along the Windsor-London-Hamilton corridor.

Some mixing could still occur near the Lake Erie shoreline, particularly in Leamington and the southern Niagara region, though it remains uncertain how far inland it may extend. If the mixing line pushes north, areas such as Windsor could also see freezing rain.

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By the end of Saturday, snowfall totals are expected to range from 5 to 10 cm across much of Southern Ontario, with locally higher amounts of up to 15 cm in areas benefiting from lake enhancement like Southwestern Ontario and the Golden Horseshoe.

Eastern Ontario and the Ottawa Valley will see lower totals, between 2 and 5 cm, as the first wave of snow stays focused farther south.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Conditions will deteriorate rapidly overnight Saturday as even more moisture-laden precipitation moves in from Michigan. Snowfall rates will increase during the pre-dawn hours, starting in the southwest around midnight before progressing east and north through the morning.

There remains some disagreement among forecast models regarding the extent of mixing along the Lake Erie shoreline, but there is a possibility of significant ice accretion in parts of Windsor and the Niagara region.

HOURLY SNOWFALL RATE/intensity - MAP FROM WEATHERBELL

By late Sunday morning, the system is expected to intensify rapidly as the low-pressure center tracks south of the Great Lakes. This intensification will result in significantly higher snowfall rates, especially in the GTA, Niagara region, and Central Ontario, including Barrie, Muskoka, and Peterborough.

Snowfall rates could reach 5-10 cm per hour, making it impossible for road crews to keep up. Eastern Ontario and the Ottawa Valley will see steady snow increase throughout Sunday afternoon and into the early evening.

ESTIMATED WIND GUSTS - MAP FROM WEATHERBELL

Adding to the severity of the storm, strong wind gusts of 50-80 km/h will develop through Sunday morning, with the highest gusts expected in Central and Eastern Ontario. These winds, combined with intense snowfall rates, will almost certainly lead to blizzard conditions in some areas.

Visibility will be near zero, with blowing and drifting snow making travel dangerous. All non-essential travel should be avoided on Sunday morning and afternoon, as highway closures are likely in the hardest-hit regions. With snow falling at rates of 5-10 cm per hour, it will be extremely easy to become stranded, as plows will struggle to keep roads passable.

PRECIPITATION TYPE - MAP FROM WEATHERBELL

Despite being less than 48 hours away, there is still some uncertainty in the storm's track and timing. Different forecast models continue to show varying scenarios, which could impact snowfall totals and the extent of mixing.

The short-range American model (HRRR), which provides detailed hourly forecasts, aligns closely with the Canadian and European models. These models suggest a more southern track, keeping the GTA and much of Southern Ontario primarily in the snow zone.

However, another American model (NAM) suggests a more northern track with a later arrival. If this scenario plays out, the mixing line would shift farther north, bringing ice pellets or freezing rain from London to Hamilton and into the GTA. This would reduce snowfall totals in these areas but create hazardous icy conditions.

This model also suggests the mixing could extend along the Lake Ontario shoreline into parts of Southeastern Ontario, including Belleville, Kingston, and Brockville. While this scenario is less likely, it’s still worth monitoring.

Additionally, the NAM model points to a significant icing event for Hamilton and the Niagara region, with potential ice accretion of 10-15 mm. If this happens, localized power outages and tree damage could occur.

The model also suggests that while some forecasts indicate the heaviest snow will arrive early Sunday, this scenario shifts the worst conditions to the afternoon in Southwestern Ontario and the GTA, extending into the evening for Eastern Ontario.

Regardless of the final track, conditions should improve as snow tapers off from west to east late Sunday evening, with lingering snow in Eastern Ontario into early Monday morning. However, lake-effect snow could quickly develop around Lake Huron and Georgian Bay as the system exits.

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By the time this storm is over, a wide swath of Eastern and Central Ontario could see 30-60 cm of fresh snow, including the accumulation from both Saturday and Sunday.

For Southwestern Ontario and the GTA—including Sarnia, London, Kitchener, Hamilton, and Toronto—snowfall totals will likely range from 20-40 cm. However, if mixing occurs on Sunday, snowfall amounts could drop to 15-30 cm or even lower, depending on how extensive the ice pellets or freezing rain become.

The lowest snowfall totals will likely be in Deep Southwestern Ontario and along the Lake Erie shoreline, where freezing rain and ice pellets will reduce overall accumulation. Areas such as Windsor, Leamington, Chatham, St. Thomas, and Niagara Falls could see between 15-30 cm of snow, depending on how much mixing occurs.

We are closely monitoring the latest forecast data and will provide a more detailed breakdown of Sunday’s snowfall totals in an updated forecast on Saturday. Stay tuned for further updates.