Thunder Bay Weather Focus – May 21, 2026: Frost Alert, Then Sunshine

Thunder Bay starts Thursday below freezing under mainly sunny skies, with a Yellow Frost Advisory in effect for the city.
Current Conditions
Observed at Thunder Bay Airport at 7:00 AM EDT:
Condition: Mainly sunnyTemperature: -1.7°CWind Chill: -4Wind: WNW 5 km/hHumidity: 91%Pressure: 103.1 kPa and risingVisibility: 32 km
Frost Advisory
Frost is expected this morning, with temperatures near or below freezing. Patchy frost may return tonight into Friday morning. Sensitive plants, trees, and cro