20-40 cm of snow set to blast parts of Ontario just days away from spring
Heavy snow will stretch across northeastern Ontario through Thursday, while the south gets another taste of pleasant spring temperatures into the teens. The dividing line between winter and spring is a bold one
The fierce battle between winter and spring will be a very apparent one across Ontario this week, as parts of the north brace for 20-40 cm of snow, while the south basks in more mild and pleasant temperatures.
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Winter storm watches are already in effect across northern Ontario, with dangerous travel expected amid heavy snow and powerful winds.
"Avoid travel if possible," says Environment and Climate Change Canada (ECCC) in the weather alert posted early Tuesday.
The storm is set to intensify Wednesday afternoon, with delays and cancellations a near guarantee.
Be sure to check highway conditions and local weather alerts before heading out this week.
Wednesday and Thursday: Heavy snow blasts through northeastern Ontario, travel not recommended
A Colorado low will pull up ample moisture from the Gulf of Mexico as it travels over the Great Lakes on Wednesday afternoon.
A mass of cold air sitting over northern Ontario will fight back against the low, with the cold, northwesterly winds wrapping around it to create a band of heavy snow over the northeast.
Snow will start early on Wednesday, picking up in intensity throughout the day until we see peak and intense snowfall rates of 3-5 cm per hour by Wednesday night.
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Winds will also whip up to 40-60 km/h, resulting in reduced visibility and blowing snow along the highways. Highway 17 will be at the greatest risk of impacts.
Wawa, Chapleau, Timmins, and Kapuskasing are currently forecast to see the heaviest snowfall totals, with 20-40 cm of wet snow possible.
Meanwhile, Sault Ste. Marie will be the dividing line between heavy rains and heavy snow, with this event starting as rain on Wednesday and transitioning to snow by Thursday. That will create a messy situation throughout the city as wet roads quickly turn to slippery slush.
Did you say 20°C? Warm air mass prevails over southern and eastern Ontario
At the same time, we'll see the typical spring-like weather continue in southern and eastern Ontario, with warm temperatures into the mid- to high teens prevailing from Ottawa to Windsor through Wednesday.
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We could possibly even see the return of the 20-degree weather for some communities in the southwest.
Conditions will remain dry until a cold front triggers rain, and possibly some thunder, on Thursday.
Changeable temperatures are expected to tip to the cold side of normal for the end of March, and continue through the first half of April, as well. We will have to closely watch the track of systems during the final week of March, as the overall pattern would support some early-spring snow.
Stay with The Weather Network for more forecast information and updates on your weather across Ontario.