Snowfall will intensify across southern Ontario until the pre-dawn hours of Thursday and will then peak through the morning hours for the Ottawa region. The storm that is creating challenging late winter conditions has prompted snowfall warnings across the Greater Toronto Area and winter storm warnings for parts of eastern Ontario including the City of Ottawa. After this system departs the region, a prolonged snow squall event will bring another round of heavy snow and some could see totals exceed 50 cm. Details and timing, below.
- Widespread amounts of 15-20 cm likely across southern Ontario, even heavier totals for central and eastern areas
- Bands of lake-effect snow develop on Thursday persisting into Saturday with the threat for dangerous whiteouts at times
- Keep track of active weather alerts in your area
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THURSDAY: TRICKY MORNING COMMUTE, SNOW PEAKS IN EASTERN REGIONS
The potent Texas low that began tracking through southern Ontario on Wednesday will continue to bring snow across the region on Thursday. The GTA and southwestern regions will see the snow taper off to flurries on Thursday morning while eastern Ontario will see the storm peak throughout the early hours of the day.
Travel could be slow and difficult, especially on roads that have not been cleared during the early hours on Thursday, and flurries could reduce visibilities for motorists.
Most of the GTA and Niagara region will see between 15-20 cm by the time all is said and done, with areas east of Toronto, including Ajax and Oshawa, picking up closer to 20-25 cm.
WINTER STORM WARNINGS IN EFFECT FOR THE EAST
Heavier snowfall amounts are expected for parts of eastern Ontario, Ottawa included, as the snow advances northeastward. Winter storm warnings are currently in effect, with significant impact expected on commute times for Thursday.
Ottawa Mayor Jim Watson has recommended that residents work from home on Thursday to reduce the number of vehicles on the roads, as the significant snowfall will be hazardous for motorists.
Between 20-40 cm could fall into Thursday and there is even the chance for some areas near the Quebec border to exceed 40 cm by the evening.
"Consider postponing non-essential travel until conditions improve," warns Environment Canada. "Rapidly accumulating snow could make travel difficult over some locations."
PLAN AHEAD: EASTERN ONTARIO WILL TAKE THE BRUNT OF THE STORM
THROUGH SATURDAY: PROLONGED AND DANGEROUS SNOW SQUALL EVENT
As the storm and system snow begins to wind down on Thursday, winds will increase with gusts of 60-80 km/h expected, creating extensive blowing and drifting snow. Don't let your guard down, because the winds combined with plunging temperatures will also set up a dangerous multi-day snow squall event.
Narrow bands of lake-effect snow squalls will develop southeast of Lake Huron and Georgian Bay, with the threat for whiteout conditions lasting well into Saturday when snowfall totals could exceed 50+ cm locally.
Bursts of heavier snow and reduced visibility will also extend into parts of the GTA at times on Thursday afternoon and evening and into parts of Friday as well.
"This will bring quick bursts of snow and rapid changes in visibility over short distances," says Weather Network meteorologist Dr. Doug Gillham, adding that this will likely be the most significant lake-effect snow event of the entire season. "This scenario brings the risk for multi-vehicle pile-ups on major highways."
BRACE FOR IMPACT: INTENSE MULTI-DAY SQUALLS TO MAKE FOR DANGEROUS TRAVEL
Check back as we continue to monitor the forecast across Ontario.