First Round of Snow Squalls To Bring Hazardous Conditions This Weekend With Up to 30–50cm of Snow for Grey-Bruce, Parry Sound & Muskoka; 10–20cm of Snow Possible for Niagara and Kingston

After a short warm-up this morning which brought temperatures across Southern Ontario near or slightly above the freezing mark, the cold air has returned pushing temperatures back down to fell below the freezing mark. As a result, we’re already seeing some lake effect snow develop off the Great Lakes this afternoon and the lake effect activity is only expected to further intensify later this evening and lasting into Saturday. With a predominately westerly to southwesterly wind direction, we’ll see the squalls develop off Lake Huron, cutting across the Bruce Peninsula and come inland to affect regions northeast and east of Georgian Bay.

This would put locations including Tobermory, Wiarton, Parry Sound, Britt, Sundridge and Huntsville in the target zone for the most intense squalls. By the end of Saturday, those locations can expect snowfall accumulation between 30-50cm with locally higher amounts. The wind direction is expected to become more westerly throughout the day on Saturday which will likely push the squalls further south stretching from Owen Sound and into Southern Muskoka such as Bracebridge and Gravenhurst.

Strong wind gusts up to 70km/h will also present a challenge due to blowing snow and near-zero visibility so travel will be likely near impossible especially through the Hwy 400 corridor between Port Severn & Sudbury along with the Hwy 11 corridor between Gravenhurst and North Bay. Avoid travel in the affected regions if possible until at least late Saturday when the squalls are expected to weaken somewhat.

When it comes to the potential accumulation, a zone encompassing the Bruce Peninsula and regions along the northeastern Georgian Bay shoreline could see as much as 30-50cm. Although this is dependent on where the squalls set up and if they lock into a particular area for an extended period of time. Further inland and southward into Southern Muskoka, locations such as Saugeen Shores, Owen Sound, Meaford. Port Carling, Bracebridge, Gravenhurst can expected total snowfall accumulation between 20-30cm. Again, the potential is there for some locations to massively underperform or overperform the forecast given how narrow and focused the bands will be. Other regions east of Georgian Bay and Lake Huron can expect between 5-15cm of fresh snowfall accumulation. These squalls may stretch quite far inland and perhaps reaching as far as Quebec so wouldn’t be surprised to see the Pembroke/Petawawa area pick up close to 10cm by the end of Saturday.

Strong snow squalls are also expected to develop off Lake Ontario and Erie starting Friday evening and mainly affecting locations south of the border. However, there are indications that the squalls could start out in Canada with a southwesterly wind direction and clip the southeastern tip of the Niagara region along with Prince Edward County and the Kingston area. Locations such as Port Colborne, Fort Erie, Prince Edward County and Kingston could see several hours of heavy snowfall overnight before the squalls shift south of the border early Saturday morning. The squalls may return periodically throughout Saturday depending on the wind direction. Total snowfall accumulation could range from 10-20cm in the most intense squalls but some locations could easily exceed that should the squalls be further north than expected.

We’ll see the lake effect activity come to an end late Saturday as an approaching system from Michigan temporarily shuts off the lake effect snow machine. This system isn’t expected to bring much in terms of snowfall with maybe at most 5cm during the day on Sunday. More snow squalls will be on the way for the next week starting with another round developing late Sunday and continuing into Monday. Similar snowfall totals are possible for the second round although the exact wind direction is still unclear and looks like it may be more of a westerly to northwesterly flow. This would target parts of Northern Simcoe County (Midland, Orillia etc.) and Southern Muskoka (Bracebridge, Gravenhurst etc.) with the heaviest snowfall. As we’ve mentioned, some parts of snowbelts are on track to see up to 100cm of snow by the end of the week with several waves of intense snow squalls over the next 7 days. Additional forecasts will be posted in the coming days so stay tuned!