The highest day temperature in January 2026 was 34°F. The lowest night temperature was -41°F. The average values for day and night temperatures during January were 3.5°F и -7.7°F respectivly.

The average sea surface temperature in January 2026 for Thunder Bay was 31.7°F. The maximum and minimum values were 31.0°F and 32.6°F respectively.

Most of the days in January are gloomy but you can also expect sunny days.

Precipitation total in January for Thunder Bay is 0.3 in. It makes january the least rainy month of the year.

The average wind speed in January is 8.3 mph.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Thunder Bay in January is 3.5 hours.