The weather in Thunder Bay in May is very cold with temperatures between 4°C and 12°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Thunder Bay during the month of May. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Please note that Thunder Bay can expect a few days of snow in May.
Our weather forecast can give you a great sense of what weather to expect in Thunder Bay in May 2025.
If you’re planning to visit Thunder Bay in the near future, we highly recommend that you review the 14 day weather forecast for Thunder Bay before you arrive.
Temperatures
12° / 4°
Rainy Days
7
Snowy Days
2
Dry Days
23
Rainfall
96
mm
Sun Hours
9.1
Hrs
