Northwestern Ontario September 20 – 22 Weather Forecast

Northwestern Ontario Weather: Morning Fog and Frost Give Way to a Sunny Start to the Week
THUNDER BAY – WEATHER DESK – Sunday, September 20, 2026 – Northwestern Ontario is moving into a quieter stretch of early-autumn weather. Fog, patchy frost and a few areas of drizzle are the main concerns early Sunday, but most communities will become sunny or partly sunny as the morning progresses.
Monday and Tuesday are expected to be mainly sunny and warmer across the region. The coldest