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

While we’ve had a break from snow squall activity over the past week, they are expected to return as we close out the week, bringing another round of lake-effect snow to areas around Lake Huron and Georgian Bay.

As the system that brought a messy mix of wintry weather moves out, colder air will briefly settle into Southern Ontario. This drop in temperature, combined with strong westerly to northwesterly winds blowing over the still mostly ice-free lakes, will create the perfect conditions for snow squall development.

Overnight Thursday, shifting winds will likely trigger several narrow bands of heavy snow that will sweep across Southern Ontario before becoming more organized over Lake Huron and Georgian Bay.

While these bands won’t last long—most areas will only see snow for 15 to 30 minutes—they could still create hazardous driving conditions. Strong wind gusts of 70-80 km/h will cause blowing snow, significantly reducing visibility on the roads.

However, for regions within the snowbelt, which have already been hit hard by squalls in recent weeks, this could be another significant snowfall event. Parts of Grey-Bruce and Simcoe County may see totals reaching 15 to 25 cm in the hardest-hit communities by the end of Friday.

**HOURLY SNOWFALL RATE/intensity** - MAP FROM WEATHERBELL

More organized squalls are likely to develop early Friday morning, targeting the Bruce Peninsula and extending into Simcoe County. This narrow but intense band will likely persist throughout much of the day, though it may shift somewhat as winds fluctuate.

Current model data indicates that the heaviest snow will remain focused within the Wiarton-to-Owen Sound corridor in Grey-Bruce and between Orillia and Barrie in Simcoe County. At times, the squall could extend further inland, bringing periods of heavy snow to parts of Kawartha Lakes, Durham, and Peterborough during the morning and afternoon.

By Friday evening, a shift in wind direction will bring a few hours of intense snowfall to parts of Southern Muskoka, including MacTier, Port Carling, Bala, Gravenhurst, and Bracebridge. However, this squall is expected to weaken quickly after midnight as winds subside.

With the snow band moving around throughout the day, widespread extreme accumulations are less likely, but it will allow more regions to see bursts of heavy snowfall at different times.

We’re expecting total snowfall accumulations of 15 to 25 cm across the central Bruce Peninsula, including Wiarton and Lion’s Head, extending into most of Simcoe County.

The City of Barrie is expected to avoid the worst of the snowfall, but if the squall sinks slightly farther south for a few hours, the city could still see around 10-15 cm of accumulation.

For the rest of Grey-Bruce, including Owen Sound, Hanover, and Collingwood, as well as Muskoka, Kawartha Lakes, and Peterborough, snowfall totals will generally range between 5 to 10 cm, though some localized pockets may receive up to 15 cm.

Outside of the snowbelt, snowfall will be minimal, with 2-5 cm expected across the rest of Central Ontario and less than 2 cm for Eastern Ontario and the Golden Horseshoe.

Deep Southwestern Ontario will likely remain snow-free from this round of lake-effect snow.

**PRECIPITATION TYPE** - MAP FROM WEATHERBELL

After the snow squalls, attention will turn to Saturday night, which, at one point, looked like it could bring Southern Ontario its strongest winter storm of the season. However, recent model data now suggests that much of the system’s moisture may stay south of the border, shifting into the U.S. Northeast instead.

If this trend continues, instead of widespread snowfall totals of 10-20 cm, most of Southern Ontario could see just 5 to 10 cm—and even that might be on the high end.

For those hoping for a big winter storm, it looks like luck isn’t on your side this time. That said, we’re still in an active storm track, and the next few weeks will bring more chances for Southern Ontario to get hit with a classic winter storm.