February 15, 2025

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

February 15, 2025/ Brennen Perry

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

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.

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.

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

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.

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.

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.

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!

February 14, 2025

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

February 14, 2025/ Brennen Perry

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

February 11, 2025

High Impact Winter Storm on the Way for Southern Ontario Starting Wednesday With Up to 40cm of Snow & Freezing Rain

February 11, 2025/ Brennen Perry

Confidence is growing that Southern Ontario is on track for what could be the most widespread and significant winter storm of the season so far. That said, there hasn’t been much competition in that regard, as most of this winter’s snowfall has come from localized snow squalls. However, a shift in the weather pattern has placed the region in an active storm track, and Mother Nature isn’t wasting any time delivering a disruptive winter storm right in the middle of the week.

Earlier, there was some uncertainty regarding the exact track of the system, which would have influenced snowfall amounts in different areas. However, in the past 24 hours, forecast models have begun to align on a more consistent storm track. Interestingly, the latest data supports what we initially projected, meaning there hasn’t been a major shift in the forecast.

Widespread snowfall accumulations of 20 to 40 cm are expected from Southwestern Ontario through Central Ontario and into the Ottawa Valley between Wednesday and Thursday. In the Golden Horseshoe and Deep Southwestern Ontario, precipitation will likely begin as snow, but there is potential for ice pellets, freezing rain, or even regular rain to mix in. This could limit snowfall totals, especially along the shorelines of Lake Ontario and Lake Erie, where temperatures may hover near the freezing mark.

For the Greater Toronto Area (GTA), the extent of mixing remains a key uncertainty. It could go either way. Right now, we’re forecasting 10 to 20 cm of snow, but if the mixing line stays south, snowfall amounts could surpass expectations, reaching 25 to 30 cm.

In Deep Southwestern Ontario, including Windsor, Chatham, and extending into the Niagara region, models suggest several hours of freezing rain Wednesday evening and overnight. Some localized areas could see ice accretion of 2 to 5 mm, leading to slippery, untreated surfaces and hazardous road conditions.

The storm is expected to arrive Wednesday afternoon, with scattered precipitation moving into Southwestern Ontario between 2 and 4 PM. While most areas will initially see snow, some models are aggressive in bringing freezing rain into Windsor and Chatham by late afternoon.

Before the main storm arrives, lake-effect snow may develop off Lake Ontario, affecting the Burlington and Hamilton corridor Wednesday morning into early afternoon. System snow should reach the GTA just before the evening rush hour, making for a difficult commute.

The latest model data has also increased wind projections, with gusts of 40 to 60 km/h in some areas. Combined with heavy snowfall, this could lead to blowing snow and reduced visibility. Non-essential travel should be avoided starting in the late afternoon, with conditions deteriorating further into the evening.

By mid to late evening, snow will have spread across most of Southern Ontario, including Central and Eastern Ontario. A key feature to monitor will be the movement of the mixing line.

Current data shows a freezing rain corridor stretching from Leamington through Chatham and along the Lake Erie shoreline, with a narrow band of ice pellets from Windsor through just south of London and into Hamilton.

Meanwhile, heavy snow will persist across Sarnia, London, Kitchener, and the GTA. Snowfall rates will intensify after 9–10 PM, increasing from 1–2 cm per hour to 2–4 cm per hour. This will make it challenging for snowplows to keep up.

After midnight, the mixing line may push north into parts of the GTA, bringing ice pellets and freezing rain to locations such as London, Burlington, Mississauga, and Toronto for several hours. However, this transition looks to be confined near the Lake Ontario shoreline, meaning snowfall will likely dominate farther inland.

Freezing rain will continue across Windsor and along the Lake Erie shoreline into the Niagara region, while heavy snow steadily blankets Central and Eastern Ontario overnight.

The system will begin its exit Thursday morning, with snow tapering off in Southwestern Ontario first. However, snow will continue across Central and Eastern Ontario.

In the Niagara region and along the Lake Ontario shoreline, mixing will remain a concern into the early morning hours. However, by 4–6 AM, colder air will push in, flipping precipitation back to snow. Any previously fallen precipitation may refreeze as temperatures drop, creating hazardous road conditions.

Expect treacherous travel conditions on Thursday morning. Roads will be slushy and icy in areas that saw mixing, while heavy snow will make roads impassable further north. Widespread school bus cancellations and school closures are likely.

Eastern Ontario will hold onto light to moderate snow through the late morning. However, models indicate some potential for mixing in the Kingston, Brockville, and Cornwall areas. This could result in light icing from freezing rain before a final transition back to snow.

Most of Southern Ontario will finally see an end to precipitation Thursday, aside from some lingering lake-effect snow near Lake Huron.

Based on the latest data, the highest snowfall totals will likely be in Central and Eastern Ontario. A widespread 20–40 cm is forecast across Southwestern, Central, and Eastern Ontario. However, totals closer to 40 cm are most probable in Eastern Ontario, including Ottawa, where there’s even a slight chance of locally exceeding 40–50 cm.

Central and Southwestern Ontario, including Grey-Bruce, Kitchener, York Region, Simcoe County, Muskoka, and Peterborough, will likely receive 20–30 cm, with some areas near Lake Simcoe potentially exceeding 30 cm.

The exception will be the Lake Ontario shoreline and the International border, including Kingston, Brockville, and Cornwall. Lower snowfall ratios and a higher risk of mixing could keep totals below 20 cm. However, if mixing remains minimal, this area could exceed forecasts.

The snowfall forecast becomes more uncertain in Deep Southwestern Ontario and the Golden Horseshoe, where multiple factors create a ‘boom or bust’ scenario. The GTA will start with heavy snow, likely reaching 10 cm fairly easily unless there’s a drastic shift in the storm track. The big question is how much more accumulates beyond that.

Some models suggest that if mixing does not occur, parts of the GTA could see 20–30 cm by Thursday morning. However, given the likelihood of overnight mixing, we expect totals to stay below 20 cm, which is why our official forecast remains at 10–20 cm.

London and Sarnia sit on the boundary between significant snow and mixed precipitation. The most probable outcome is 15–20 cm, though an overperformance remains possible.

In Deep Southwestern Ontario and the Niagara region, snowfall amounts will be lower, with less than 10 cm expected. However, these areas will likely see prolonged freezing rain, with the heaviest ice accretion along the Lake Erie shoreline.

Models vary on how intense the freezing rain will be. Some project as much as 10 mm of ice accretion, but this seems unlikely given the presence of mixed precipitation and the relatively short duration of freezing rain. Our official forecast calls for 2–5 mm of ice accretion, though isolated pockets could see 7–10 mm if freezing rain persists longer than expected.

February 11, 2025

Major Winter Storm on Track to Dump Up to 40cm of Snow Across Most of Southern Ontario Starting Wednesday

February 11, 2025/ Brennen Perry

Get your shovels ready, Southern Ontario! What many would consider our first true winter storm of the season is on the horizon. This moisture-laden system is set to arrive Wednesday afternoon, bringing heavy snowfall across a large portion of our region.

There’s still some uncertainty in the exact track, which will determine who sees the heaviest snow, but confidence is growing that much of Southern Ontario will experience significant impacts from this storm. Travel will likely become hazardous Wednesday evening into Thursday morning, and widespread school bus cancellations—and even full school closures—are almost certain on Thursday.

Based on the latest data, the heaviest snowfall is expected to stretch from Southwestern Ontario through Central Ontario and into the Ottawa Valley. Accumulations will likely range between 20 to 40 cm, with some localized pockets potentially exceeding 40 cm by the time the snow tapers off early Thursday afternoon.

The most challenging part of this forecast comes down to a narrow corridor from London through Hamilton, into the Greater Toronto Area (GTA), along the Lake Ontario shoreline, and into extreme Eastern Ontario along the international border. These areas are likely to start off with snow, but depending on the storm’s track, a transition to ice pellets, freezing rain, or even regular rain could occur during the evening and overnight.

The exact snowfall amounts in this corridor remain highly uncertain, as even a fraction of a degree difference in temperature could mean the difference between 5 cm and 30 cm of snow.

The risk of freezing rain also appears significant for areas in deep Southwestern Ontario, including Windsor, Chatham, and communities along the Lake Erie shoreline, where several hours of ice accretion could result in hazardous road conditions and localized power outages.

The storm will begin impacting Southern Ontario on Wednesday afternoon, with the initial bands of snow spreading into deep Southwestern Ontario, including Windsor, Sarnia, Chatham, and London. By the mid-to-late afternoon, snow will have moved into Hamilton, Niagara, and the Greater Toronto Area, just in time for the evening commute.

Steady snowfall will continue through the dinner hour, with snowfall rates gradually increasing as the system spreads further across the region. Central and Eastern Ontario will see snow begin around the dinner hour into the early evening, while the Ottawa Valley may not see the first flakes until mid-to-late evening.

Snow will continue throughout the night across much of the region, with varying intensity. Unlike some past storms, this event isn’t expected to bring extreme snowfall rates, with accumulations of around 2 to 4 cm per hour at most. However, the prolonged nature of this storm, lasting 12 to 16 hours in many areas, will allow totals to build up significantly.

Another key factor in determining final snowfall amounts will be how far north the mixing line extends into Southern Ontario. Earlier model runs suggested a more northern track, which would allow warmer air to push into areas along the Lake Erie and Lake Ontario shorelines, leading to a transition from snow to ice pellets, freezing rain, or rain.

However, more recent model data from Monday evening has trended slightly further south, reducing the risk of mixing for some areas. That said, some models, including the American (NAM) and European models, still show a more northern mixing line, which could bring ice and rain into parts of deep Southwestern Ontario, London, and Hamilton.

If this occurs, Windsor and areas along the Lake Erie shoreline could see several hours of freezing rain, resulting in ice buildup on untreated surfaces, power lines, and roads.

On the other hand, the Canadian (RGEM) model, along with the higher-resolution American NAM 3km model, suggest a more southern storm track, which would keep most of Southern Ontario in the snow zone.

If this scenario plays out, snowfall accumulations could be much higher in places like London, Hamilton, and the Golden Horseshoe, with totals ranging from 20 to 30 cm and minimal mixing.

Some models also indicate the possibility of mixing slightly north of Lake Ontario and along the St. Lawrence River, including Kingston, Brockville, and Cornwall, which could lower snow totals in these areas. However, the latest data suggests this region may stay entirely on the snowy side of the system.

As the storm progresses overnight, those areas that remain on the snow side will continue to see accumulation through early Thursday morning. Snowfall rates could briefly reach 2 to 4 cm per hour in heavier bands but will likely average closer to 1 to 2 cm per hour.

Fortunately, winds won’t be particularly strong, with gusts expected to range from 20 to 40 km/h at most. While some blowing snow is possible, full-blown blizzard conditions are not expected with this storm.

By mid-morning Thursday, high-resolution models suggest a final burst of heavier snow around the Golden Horseshoe, Lake Simcoe, and Eastern Ontario. Snowfall rates could briefly spike to 4 to 6 cm per hour as the back end of the system moves through during the morning rush hour.

Travel conditions will likely be very poor on Thursday morning, and all non-essential travel should be avoided. Widespread school bus cancellations are almost a certainty given these conditions.

A rapid improvement is expected in Southwestern Ontario by late morning, with snowfall tapering off to light flurries. However, it will take time for road crews to clear the heavy snowfall, so road conditions may remain hazardous into the early afternoon.

For Central and Eastern Ontario, snow will linger into the early afternoon before finally winding down around midday for the GTA and Central Ontario and mid-afternoon for the Ottawa Valley.

By the time the storm wraps up, a broad region across Southern Ontario, including the Lake Huron shoreline, Sarnia, Kitchener, Barrie, Muskoka, Peterborough, and the Ottawa Valley, will likely see between 20 and 40 cm of fresh snow. Mixing is unlikely to be a factor in these areas, though there’s always a slight chance of a last-minute shift in the storm track.

The biggest uncertainty lies within a narrow corridor that includes London, Woodstock, Hamilton, Mississauga, Toronto, Belleville, Kingston, Brockville, and Cornwall. This area will likely begin with snow on Wednesday but could see ice pellets, freezing rain, or rain mix in during the late evening and overnight hours, which would reduce total snowfall amounts.

A conservative estimate for this region is at least 10 cm of snow, though some areas, particularly along the northern edge of this zone, could see totals closer to 20 to 30 cm. The current model trends lean toward a slightly more southern storm track, but we are waiting to see if this pattern holds before making final adjustments to the snowfall forecast.

For Windsor, Chatham, and areas along the Lake Erie shoreline, including Niagara, a mix of snow and freezing rain is expected. Some locations could experience several hours of freezing rain, leading to ice accretion of 4 to 8 mm, which may cause localized power outages. However, if the mixing line remains further south, these areas could still end up seeing significant snowfall, possibly exceeding 20 cm.

The bottom line is that while we have high confidence in a significant winter storm, the local impacts will ultimately depend on the storm’s exact track, which may not become fully clear until just before the system moves in.

A more detailed forecast with refined snowfall and freezing rain estimates will be released late Tuesday as newer model data becomes available.

February 07, 2025

Snowy System Brings Double Digit Snowfall Accumulation to Greater Toronto Area & Southwestern Ontario This Weekend

February 07, 2025/ Brennen Perry

While many parts of Southern Ontario have been hit hard by snow squalls this winter, others have barely seen any accumulation.

The snowbelt regions east of Lake Huron and Georgian Bay have faced relentless lake-effect snow, while areas like Deep Southwestern Ontario, the Golden Horseshoe, and Southeastern Ontario have largely remained outside the squall zones.

The reason? This winter has been dominated by localized snow squalls rather than widespread storms. The extreme cold throughout January kept the storm track well south of the Great Lakes, shielding much of the region from major systems.

Aside from the occasional Alberta Clipper, it’s been relatively quiet. But that’s about to change as we shift into a more active storm track that places Southern Ontario directly in its path.

A moderately strong snowy system is on track to bring steady, accumulating snowfall across a wider area, including the GTA—one of the least snowy regions so far this season. Snow is expected to begin Saturday afternoon, with the heaviest accumulation occurring Saturday evening.

In fact, this system could bring Toronto its largest one-day snowfall of the season. The city’s current highest daily total sits at just 6.6 cm, recorded in early December. But with this storm, a widespread 10-15 cm of snow is looking increasingly likely, with some areas west of Lake Ontario possibly approaching 20 cm due to lake enhancement.

The first snow bands will push into Southern Ontario from the west by mid-afternoon Saturday, with flurries likely developing east of Lake Huron between 2-4 PM before spreading into the GTA around the dinner hour.

At first, the snowfall will be light, but intensity will gradually increase through the late afternoon and early evening as stronger snow bands move in. Windsor and Chatham could see some mixed precipitation, with a chance of freezing rain or drizzle before switching over to snow.

By early evening, snowfall will expand across most of Southern Ontario, bringing steady accumulation.

The heaviest snow is expected west of Lake Ontario, stretching into Kitchener and Goderich, where snowfall rates could reach 1-2 cm per hour.

**ESTIMATED WIND GUST** - MAP FROM WEATHERBELL

Winds gusting 40-50 km/h along the Lake Erie shoreline Saturday evening may not be extreme, but they could still create minor blowing snow when combined with the steady snowfall, making travel conditions tricky.

Snow will continue falling through the evening, gradually spreading toward Eastern Ontario. While Ottawa might see some light snow, accumulation should remain minimal.

The heaviest snow in Eastern Ontario will focus along the Lake Ontario shoreline, including Belleville and Kingston.

As we approach midnight, snow will begin tapering off from west to east, with Lake Huron regions clearing out first. For the GTA, heavier snow may persist a few hours past midnight before gradually weakening.

By early Sunday morning, the system will have moved out of most of Southern Ontario, with only lingering light snow possible in Eastern Ontario.

Recent model trends suggest a stronger system than initially expected, though there remains some uncertainty. Forecasts have bounced between 5-10 cm and 15-25 cm in different model runs.

The current consensus suggests a general 10-15 cm corridor extending from Lake Huron through Kitchener, the Golden Horseshoe, and into the Kingston area, with localized pockets nearing 20 cm.

For areas further north, including Simcoe County, Kawartha Lakes, and Brockville, as well as Sarnia and London, 5-10 cm of snow is expected.

The least snowfall will be in the Ottawa Valley, where less than 5 cm is likely. Deep Southwestern Ontario, including Windsor and Chatham, will see the lowest totals, with 2-5 cm possible, along with the risk of freezing rain.

This will be one of the most widespread snowfalls of the season, especially for regions that have barely seen measurable snow this winter. Stay tuned for further updates as the system approaches.

February 02, 2025

Willie Is Wrong! February Roars Into Southern Ontario With Up to 10cm of Snow for Central & Eastern Ontario on Monday

February 02, 2025/ Brennen Perry

Wiarton Willie emerged from his burrow on Sunday morning and didn’t see his shadow, predicting an early spring. But as Southern Ontario residents wake up to an active weather pattern, it looks like Mother Nature may have other plans.

A stormy week is ahead, with multiple systems taking aim at the region. The first arrives Monday, bringing a messy mix of heavy snow, freezing rain, and rain. Central and Eastern Ontario will bear the brunt of the snowfall, while areas northwest of the GTA could see prolonged freezing rain.

The most significant concern, however, is a potentially high-impact storm on Thursday. Current model data points to a prolonged freezing rain event for Southwestern Ontario and the Golden Horseshoe, though the exact track remains uncertain. A slight shift north or south could change precipitation types and affected areas.

The first storm system of the week will begin affecting Southern Ontario late Monday morning. Light to moderate snow will spread into Grey-Bruce, Muskoka, Parry Sound, and areas east of Georgian Bay.

At the same time, a light freezing drizzle could develop across parts of the GTA, Kitchener, and London, though it should remain fairly light and not overly impactful. Still, untreated roads and sidewalks could become slick.

By early to mid-afternoon, the storm will intensify, with moderate to heavy snow spreading into Central and Eastern Ontario, including Ottawa, Peterborough, and Barrie.

At the same time, freezing rain may become prolonged in a narrow corridor northwest of the GTA, affecting Shelburne, Orangeville, and northern York Region.

Further south, rain will dominate along the Lake Ontario shoreline and into Southwestern Ontario.

As Monday evening approaches, the storm will begin to taper off from west to east. Snow will transition to flurries in Southwestern Ontario around dinnertime, while Central and Eastern Ontario will see precipitation continue into the evening before ending around midnight.

However, freezing rain may linger longer in higher elevations northwest of the GTA, potentially impacting Guelph and Kitchener.

While this storm won’t produce extreme snowfall rates, widespread accumulation is expected across Central and Eastern Ontario. Most areas from Grey-Bruce through Muskoka, Simcoe County, Peterborough, Kingston, Ottawa, and Cornwall will see 5 to 10 cm of snow.

Localized areas near Georgian Bay could exceed expectations, as lake enhancement may fuel pockets of heavier snow, pushing some totals closer to 15 cm. However, confidence remains low in this scenario, so no forecast upgrades have been made to the 10-20 cm range.

South of these regions, snowfall amounts will drop quickly as precipitation transitions to freezing rain and rain. The northern GTA and Durham Region could see 2-5 cm of accumulation, with icing concerns in a narrow corridor stretching from Kincardine through Orangeville, Newmarket, Oshawa, Belleville, and Kingston.

Freezing rain could be persistent, with most areas seeing around 2 mm of ice accretion.

However, in higher elevations like the Dundalk Highlands, up to 4 mm of ice could accumulate, increasing the risk of localized slick conditions.

As Monday’s system moves out, attention turns to a more significant storm later in the week.

A major winter storm is possible on Thursday, with global weather models consistently highlighting the risk of prolonged freezing rain. Right now, Southwestern Ontario and the Golden Horseshoe appear to be in the bullseye. However, the storm’s track remains uncertain, and even a small shift north or south could drastically alter the precipitation types and affected areas.

A more southerly track would favour a snowstorm for Southern Ontario.
A more northerly track would put Central and Eastern Ontario at risk for significant icing.

Regardless of the final path, Thursday’s storm could bring major disruptions, particularly to the morning commute. Widespread school bus cancellations appear likely based on current data, though details may change as the system evolves.

Stay tuned for updates as we track these storms!

December 22, 2024

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

December 22, 2024/ Brennen Perry

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.

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.

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.

December 07, 2024

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

December 07, 2024/ Brennen Perry

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

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

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

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

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

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

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

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

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

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

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

November 21, 2024

Another Snowstorm Could Dump Up to 30cm of Snow on Saskatchewan & Manitoba This Weekend

November 21, 2024/ Brennen Perry

As residents across parts of Saskatchewan and Manitoba begin digging out from the first significant snowfall of the season, another winter storm is already on the horizon.

Snowfall is expected to start in western Saskatchewan as early as Saturday morning, with the worst conditions anticipated over the weekend. By the time the system wraps up on Monday, widespread snow accumulation of 15 to 30 cm is likely.

Although current model data shows good consistency regarding the storm's intensity and track, it’s still over 24 hours away, and some slight adjustments are possible. Be sure to check back on Friday for our updated forecast, which will include more precise snowfall accumulation predictions.

A teaser of what’s to come will arrive on Friday as light snow begins moving into southwestern Saskatchewan during the afternoon. This snowfall isn’t expected to spread far across the province and should mostly fizzle out by Saturday morning. Areas like Maple Creek and Shaunavon could see a few centimeters of accumulation, possibly up to 5 cm.

However, the break in snowfall will be brief, as another wave of precipitation sweeps into the province from Alberta. This system will begin as light snow late Saturday morning, gradually increasing in intensity throughout the afternoon.

By the evening, snowfall will have reached Saskatoon and Regina, with moderate to heavy snow spreading across much of Saskatchewan. The worst conditions are expected overnight into Sunday morning, when snowfall rates will peak.

Blowing snow could also pose a concern, with wind gusts of 40-50 km/h reducing visibility on roads. While conditions aren’t expected to meet blizzard criteria, drivers should anticipate poor travel conditions and potential highway closures beginning Saturday evening, particularly in western Saskatchewan. Road conditions will likely remain hazardous until Sunday afternoon, starting with improvements in the western parts of the province.

By the early hours of Sunday, snowfall will have reached western Manitoba, with its intensity ramping up through the morning. Current forecasts suggest the heaviest snowfall will target central portions of western Manitoba, including the Interlake region.

Brandon is expected to see snow begin late Sunday morning, with light to moderate snowfall continuing throughout the day. Winnipeg will likely see snow begin in the early afternoon, continuing into the evening and overnight hours.

Snowfall will gradually taper off by Monday morning, with lingering flurries in central parts of Saskatchewan and Manitoba.

The storm is expected to lose some intensity as it progresses eastward across the Prairies. This means the highest snowfall totals will likely occur in western and central Saskatchewan. Snowfall amounts of 20-30 cm are expected in these areas by Monday morning, with localized pockets exceeding 30 cm. Locations such as Swift Current, Moose Jaw, Regina, and Kindersley are within this high-impact zone.

For the rest of Saskatchewan, snowfall amounts are forecast to range between 5 and 15 cm, with some areas potentially nearing 20 cm depending on the storm’s exact track. We’ve opted for a general forecast of "up to 20 cm" for now but expect refinements in our final update.

In Manitoba, western regions—including areas already hit hard by the earlier storm this week—can expect 10-15 cm, with isolated totals approaching 20 cm. Areas east of Brandon, including Winnipeg, are forecast to see lighter accumulations of 5-10 cm. Snowfall totals will taper off further north, with minimal impacts expected in northern Manitoba.

**ESTIMATED WIND CHILL ON SATURDAY MORNING** - MAP FROM WEATHERBELL

One significant difference between this storm and the one earlier this week is the temperature. This event will be accompanied by much colder air, meaning it will produce all snow, with no risk of mixed precipitation. Additionally, colder temperatures will result in higher snowfall ratios, so it won’t take much liquid precipitation to produce substantial snowfall amounts.

This colder air also brings added risks for anyone traveling during the storm. Extremely cold wind chills are expected to develop as early as Saturday, with some areas feeling like the -20s across Saskatchewan and into Manitoba. If you get stranded on the roads, staying warm may be difficult, so it’s highly recommended to avoid travel during this storm.

Weather Forecasts & Articles

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

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

High Impact Winter Storm on the Way for Southern Ontario Starting Wednesday With Up to 40cm of Snow & Freezing Rain

Major Winter Storm on Track to Dump Up to 40cm of Snow Across Most of Southern Ontario Starting Wednesday

Snowy System Brings Double Digit Snowfall Accumulation to Greater Toronto Area & Southwestern Ontario This Weekend

Willie Is Wrong! February Roars Into Southern Ontario With Up to 10cm of Snow for Central & Eastern Ontario on Monday

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

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

Another Snowstorm Could Dump Up to 30cm of Snow on Saskatchewan & Manitoba This Weekend

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