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Live forecasts update automatically; written guidance last reviewed 16 June 2026 by the True North Brief Weather Desk. Data from Environment and Climate Change Canada and other national met services via Open-Meteo.
Check Environment Canada’s warnings before heading out: accumulations of 15 cm or more within 12 hours trigger a snowfall warning. Driving conditions become hazardous, so plan for delays or stay home if possible.
What snowfall amounts trigger a warning?
Environment and Climate Change Canada issues a snowfall warning when 15 cm or more is expected in 12 hours (or 20 cm in 24 hours). In some regions, the threshold drops to 10 cm if the snow is heavy, wet, or accompanied by strong winds. The yellow warning snowfall meaning: be alert for reduced visibility and rapidly accumulating snow that can make roads impassable.
Where are snow warnings active today?
As of now, ontario weather warnings today cover large parts of southern and northern Ontario. A southern ontario weather warning today typically affects the Greater Toronto Area, Hamilton, and the Niagara corridor. Northern ontario weather warnings today often span from Sudbury to Thunder Bay, with higher accumulations due to lake-effect bands. For the latest weather warnings snow map, refer to the official sources below. For weather warnings snow tomorrow, forecasts suggest similar bands may persist.
What is the difference between a snowfall warning and a winter storm warning?
A snowfall warning applies only to snow accumulation (≥15 cm in 12 h). A winter storm warning includes additional hazards such as freezing rain, ice pellets, or blizzard conditions.
How long do snow warnings typically last?
Most warnings remain in effect for 6 to 24 hours, matching the passage of the weather system. The warning is lifted once accumulation slows and conditions improve, but roads may stay slippery.
Should I travel during a snow warning?
Travel is strongly discouraged unless essential. Roads become snow-covered and visibility drops suddenly. If you must drive, carry an emergency kit and reduce speed. Check Weather Warnings Canada before departing.