Average annual temperature is 5.0 °C
Absolute maximum temperature: 29.6 °C
Absolute minimum temperature: -27.7 °C
Number of sunny days: 186 days
Number of rainy days: 134 days
Number of snow days: 45 days
Look at detailed online map of Thunder Bay
* Weather data for Thunder Bay Canada is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 1.6 | 4.7 | 3.5 | 16.5 | 25.9 | 27.4 | 26.8 | 28.2 | 29.6 | 25.6 | 13.5 | 9.1 |
| Average daytime temperature (°C) | -4.7 | -5.1 | -1.0 | 4.8 | 14.5 | 19.4 | 21.0 | 21.6 | 19.0 | 10.8 | 3.5 | 2.0 |
| Average temperature (°C) | -7.7 | -9.1 | -4.7 | 0.8 | 9.2 | 14.9 | 16.6 | 17.4 | 15.3 | 7.8 | 0.0 | -1.0 |
| Average night temperature (°C) | -10.4 | -12.8 | -8.2 | -2.4 | 4.7 | 10.6 | 12.9 | 13.8 | 12.3 | 5.3 | -2.9 | -3.6 |
| Absolute minimum temperature (°C) | -24.9 | -27.7 | -15.7 | -10.0 | -1.4 | 7.1 | 8.4 | 8.8 | 5.5 | -4.6 | -13.8 | -10.7 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 9.0 | 10.0 | 12.0 | 14.0 | 15.0 | 16.0 | 16.0 | 15.0 | 13.0 | 11.0 | 9.0 | 8.0 |
| Daylight mean duration (h) | 8.8 | 10.2 | 11.9 | 13.7 | 15.2 | 16.0 | 15.6 | 14.3 | 12.6 | 10.8 | 9.2 | 8.4 |
| Daylight minimum duration (h) | 8.0 | 9.0 | 11.0 | 12.0 | 14.0 | 15.0 | 15.0 | 13.0 | 11.0 | 9.0 | 8.0 | 8.0 |
| Sunshine mean duration (h) | 4.2 | 6.6 | 7.5 | 7.1 | 10.8 | 11.8 | 12.1 | 10.9 | 8.8 | 5.6 | 4.9 | 3.1 |
| Precipitation (mm) | 28 | 44 | 45 | 137 | 56 | 64 | 77 | 58 | 64 | 59 | 31 | 40 |
| Sunny days | 19 | 15 | 24 | 10 | 19 | 21 | 9 | 13 | 13 | 13 | 16 | 14 |
| Rainy days | 1 | 2 | 1 | 15 | 12 | 9 | 22 | 18 | 17 | 18 | 9 | 10 |
| Snow days | 11 | 11 | 6 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 5 | 7 |
The best time to visit Thunder Bay during the most sunny months:
Months with the longest average daylight duration in Thunder Bay:
The largest precipitation sum in Thunder Bay is at