Messy storm soaks Ontario with wintry cocktail of rain, snow and winds
Blowing snow and frigid temperatures will make a quick comeback across southern Ontario on Thursday, creating hazardous travel conditions, and bitter wind chills after Wednesday's heavy rain and milder weather
Weather warnings and alerts are widespread across Ontario, as a potent Colorado low is bringing everything from significant snow to flooding rains, and powerful winds, with falling temperatures through Thursday. There's even the chance for rumbles of thunder with some heightened instability across the south.
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This could end up being one of the strongest storms on record in March, in terms of low pressure over the Great Lakes.
Because of the amount of rainfall and warming temperatures expected in southern Ontario, there is a raised threat of localized flooding and ice jams as the low makes its way through. Local conservation authorities are on alert for possible river flooding.
Flood watches and warnings are in effect.
Meanwhile, winter storm warnings cover sections of northern Ontario, with heavy snow and reduced visibility expected to impact travel. Drivers are urged to postpone non-essential travel until conditions improve. Impacts from the storm span over 2000 km from Central Canada into the Maritimes.
Stay up-to-date on your local weather alerts, and be sure to check the latest highway conditions before heading out on the roads.
Southern Ontario: Heavy rain picks up, risk of river and overland flooding
Expect Wednesday to be a washout across southern and eastern sections of the province.
A swath of 10-30 mm of rainfall is possible, elevating the localized flood risk with rapid snowmelt, particularly in areas with a considerable snowpack. Ice jams will also be possible in more flood-prone areas, including the Grand River watershed.
Thunder is possible
Southern Ontario, including the Greater Toronto Area (GTA), could even hear a rumble or two with a little more instability and dynamics in place on Wednesday.
The most favourable setup for severe weather, however, will remain far south of the border.
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Quickly falling temperatures with strong winds and blowing snow on Thursday
As the storm exits east out of the province on Thursday, a noticeable drop in temperatures will see rainfall change into blowing snow for parts of southern and eastern Ontario. The rapidly falling temperatures, combined with rain changing to snow, could result in surfaces becoming icy and slippery, as well.
Expect 50-70 km/h wind gusts and bouts of snowfall, which could slow travel Thursday through Thursday afternoon.
The Greater Ottawa Area may also see snowfall during the Thursday evening commute.
Northern Ontario: Travel not recommended as heavy snow pushes through
Northern Ontario remains on the colder side of the low, with winter storm warnings in effect across the region.
The system will dump heavy snowfall and generate blustery winds on Wednesday, leading to treacherous winter weather near Sudbury, North Bay, Sault Ste. Marie and Timmins.
A swath of 10-20+ cm of snow is possible, with hazardous travel expected on Highway 11 and Highway 17. In Timmins, between 20-30 cm of snow could fall.
Blowing snow is then expected on Thursday as the storm exits east, especially for some of the snowbelt regions.
Stay with The Weather Network for all the latest on conditions across Ontario.