Thunder Bay Weather Update – May 18, 2026: Damp Victoria Day with More Rain Tonight

Thunder Bay Weather Update May 18 2026

THUNDER BAY – WEATHER – Thunder Bay is closing out the Victoria Day long weekend under light rain, drizzle, and very humid conditions. The damp pattern continues tonight, with another round of rain moving in after midnight and a risk of freezing rain Tuesday morning.

It is a wet start to the day, so grab your raincoat, umbrella and lets get on with the day.

Current Conditions

Observed at 7:00 AM EDT:

Condition: Light rain
Temperature: 6.9°C
Humidity: 99%
Wind: NE 13 km/h
Pressure: 100.7 kPa and falling
Visibility: 10 km

Today’s Forecast

Rain or drizzle will end near noon, then skies remain cloudy.

High: 12°C
Rainfall: 5 to 10 mm

Tonight and Tuesday

Tonight: Cloudy, with rain beginning after midnight. Low 0°C. Rainfall amount 5 to 10 mm.

Tuesday: Rain ending near noon, then cloudy. There is a risk of freezing rain in the morning. High 6°C.

Tuesday Night: Cloudy with a 30% chance of rain showers or flurries. Low 0°C.

Lake Superior Marine Weather

Conditions on Lake Superior will remain unsettled through Tuesday as rain, drizzle, and cool northeast flow affect the north shore.

Boaters should expect reduced visibility in rain and drizzle, cold air over the water, and choppy conditions at times. Small craft operators should use extra caution, especially near exposed shoreline areas and harbour approaches.

Cold water remains a serious hazard. Wear a lifejacket or flotation gear, dress for immersion conditions, and check the latest marine forecast before heading out.

Midweek Outlook

Wednesday stays cloudy and cool with a high of 8°C. Conditions improve Thursday with sunshine and a high of 16°C, followed by a brighter stretch into the weekend.

What to Wear

Wear waterproof footwear, a rain jacket, and warm layers. Drivers should be alert Tuesday morning for slick roads if freezing rain develops.

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