Thunder Bay Weather in December
Average highs run from -3°C on December 1 to -9°C on December 31, and lows from -10°C to -17°C. Normal precipitation for the month is 31 mm over about 9 wet days.
December day by day
The normal high and low for each date, in °C.
- Normal low
- Normal high
- Reanalysis extreme high
- Reanalysis extreme low
December at a glance
- Average high
- -6°C
- Average low
- -14°C
- Precipitation
- 31 mm
- Reanalysis high
- 5°CDec 3, 2012
- Reanalysis low
- -35°CDec 31, 2013
- Daylight
- 8 h 38 min to 8 h 24 min
- Cloud cover
- 71%
- Humidity
- 93%
- Dew point
- -11°C
- Wind
- 11.9 km/h
Every day of the month
A wet day has at least 1 mm of precipitation in the reanalysis.
| Date | Normal high | Normal low | Reanalysis high | Reanalysis low | Chance wet |
|---|---|---|---|---|---|
| Dec 1 | -3°C | -10°C | 4°C 1998 | -21°C 1991 | 27% |
| Dec 2 | -3°C | -10°C | 4°C 2017 | -26°C 1991 | 26% |
| Dec 3 | -4°C | -11°C | 5°C 2012 | -20°C 2005 | 26% |
| Dec 4 | -4°C | -11°C | 3°C 2015 | -26°C 1991 | 26% |
| Dec 5 | -4°C | -11°C | 4°C 2015 | -27°C 1991 | 24% |
| Dec 6 | -4°C | -12°C | 5°C 2015 | -20°C 2008 | 24% |
| Dec 7 | -5°C | -12°C | 2°C 1999 | -21°C 1995 | 24% |
| Dec 8 | -5°C | -12°C | 5°C 2015 | -24°C 2013 | 25% |
| Dec 9 | -5°C | -12°C | 4°C 2020 | -23°C 2007 | 25% |
| Dec 10 | -5°C | -13°C | 3°C 2015 | -25°C 1995 | 26% |
| Dec 11 | -5°C | -13°C | 3°C 2002 | -29°C 1995 | 25% |
| Dec 12 | -6°C | -13°C | 3°C 1999 | -29°C 1995 | 24% |
| Dec 13 | -6°C | -13°C | 2°C 2002 | -28°C 2013 | 23% |
| Dec 14 | -6°C | -13°C | 4°C 1998 | -28°C 2010 | 22% |
| Dec 15 | -6°C | -13°C | 3°C 1997 | -25°C 2013 | 24% |
| Dec 16 | -6°C | -13°C | 2°C 2001 | -29°C 2008 | 24% |
| Dec 17 | -6°C | -14°C | 2°C 2001 | -24°C 2016 | 23% |
| Dec 18 | -6°C | -14°C | 2°C 1997 | -28°C 2016 | 22% |
| Dec 19 | -6°C | -14°C | 2°C 2018 | -30°C 2004 | 23% |
| Dec 20 | -7°C | -14°C | 2°C 1994 | -26°C 2008 | 24% |
| Dec 21 | -7°C | -15°C | 3°C 1994 | -23°C 2008 | 25% |
| Dec 22 | -7°C | -15°C | 3°C 1994 | -27°C 2004 | 24% |
| Dec 23 | -7°C | -15°C | 3°C 1994 | -30°C 2004 | 24% |
| Dec 24 | -8°C | -15°C | 2°C 1994 | -31°C 2004 | 25% |
| Dec 25 | -8°C | -16°C | 3°C 1999 | -31°C 1993 | 25% |
| Dec 26 | -8°C | -16°C | 3°C 1994 | -34°C 1993 | 25% |
| Dec 27 | -8°C | -16°C | 1°C 2003 | -31°C 1993 | 27% |
| Dec 28 | -8°C | -16°C | 2°C 2003 | -29°C 1993 | 27% |
| Dec 29 | -9°C | -17°C | 0°C 2010 | -30°C 2013 | 26% |
| Dec 30 | -9°C | -17°C | 1°C 2010 | -33°C 2013 | 25% |
| Dec 31 | -9°C | -17°C | 1°C 2006 | -35°C 2013 | 24% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (EST).
- December 1
- sunrise 8:27 AM, sunset 5:05 PM
- December 31
- sunrise 8:48 AM, sunset 5:12 PM
Other months
Sources
Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.