Chilly air, snow creep into Ontario for the first weekend of spring
Chilly temperatures and a return to snowy conditions will make the first weekend of spring feel more like a stubborn retread of winter
The first weekend of astronomical spring feels like a continuation of the same old pattern across Ontario as an active system scoots across the region.
We’re watching a Montana low tracking in from the Rockies that could bring accumulating snow to much of southern Ontario late Sunday into early Monday.
Beware slick spots if you have to travel during periods of snow, and keep an eye on highway conditions before you head out and about.
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Chilly air dominates this weekend—and beyond
A very chilly airmass by late-March standards has swept across northern Ontario, pushing temperatures down below -30°C in Weagamow Lake on Saturday morning.
This is roughly 15 degrees below seasonal for this time of year.
The heart of the cold will shift into northeastern Ontario by Sunday morning, setting the stage for some messy weather as our system tracks into the region to close out the weekend.
Toronto, Ottawa to see a touch of snow
A period of wet snow is expected to develop late Sunday evening across the Greater Toronto Area (GTA), especially north of the QEW. This includes communities north of the GTA along Highways 401 and 400.
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The heaviest wet snow is expected after midnight. A few centimetres of snow could fall around the GTA where temperatures will hover around the freezing mark. Folks away from Lake Ontario and at higher terrain could see up to 5 cm of snow from this event.
We’ll see a more disorganized system moving into eastern Ontario, including Ottawa, during the overnight hours Sunday into Monday.
Generally, totals of 3-5 cm are on tap for most areas in eastern Ontario through Monday, though locally higher amounts are possible along Highways 7, 41, and 60 near Algonquin—where up to 10 cm is possible.
Cottage country, northeastern Ontario are the snow winners
Cottage country and northeastern Ontario are the places to be if you’re rooting for winter to hold its ground against spring’s slow but steady advance.
Moderate snowfall will develop here through the pre-dawn hours Monday, with periods of heavy snow lingering around Georgian Bay on Monday morning as the low-pressure system lifts northward.
This will be an all-snow event thanks to higher elevations and colder air in place; the heavier and more organized snow will extend up to North Bay.
Accumulations here will come in around 5-10 cm for most areas, with locally higher amounts possible under the heaviest snowfall.
Chilly to end March
Looking ahead, there’s not much good news for warm-weather lovers in the forecast through the end of the month.
Below-seasonal temperatures are expected to hold tight across southern Ontario heading into the final full week of March, potentially lingering into the opening days of April.
Forecasters will closely watch the track of any low-pressure systems, as their associated warm fronts could drag temporary bursts of warm air north of the border.