Thermopolis Weather in December
Average highs run from 41°F on December 1 to 37°F on December 31, and lows from 16°F to 11°F. Normal precipitation for the month is 0.46 in over about 3 wet days.
December day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
December at a glance
- Average high
- 38°F
- Average low
- 12°F
- Precipitation
- 0.46 in
- Snowfall
- 4.5 in
- Record high
- 78°FDec 10, 1939
- Record low
- -38°FDec 18, 1924
- Chance of a freeze
- 100%
- Daylight
- 9 h 10 min to 9 h 00 min
- Cloud cover
- 64%
- Humidity
- 67%
- Dew point
- 15°F
- Wind
- 8.5 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Dec 1 | 41°F | 16°F | 67°F 1995 | -8°F 1908 | 12% | 8% |
| Dec 2 | 40°F | 16°F | 67°F 2021 | -8°F 1908 | 12% | 8% |
| Dec 3 | 40°F | 15°F | 62°F 1958 | -9°F 1928 | 11% | 8% |
| Dec 4 | 40°F | 15°F | 60°F 2007 | -24°F 1909 | 11% | 8% |
| Dec 5 | 39°F | 15°F | 70°F 1939 | -30°F 1909 | 11% | 8% |
| Dec 6 | 39°F | 14°F | 72°F 1939 | -16°F 1909 | 11% | 8% |
| Dec 7 | 39°F | 14°F | 59°F 1939 | -26°F 1909 | 11% | 8% |
| Dec 8 | 38°F | 14°F | 68°F 1940 | -20°F 1932 | 11% | 8% |
| Dec 9 | 38°F | 13°F | 65°F 1939 | -24°F 2009 | 11% | 8% |
| Dec 10 | 38°F | 13°F | 78°F 1939 | -25°F 1932 | 11% | 8% |
| Dec 11 | 38°F | 13°F | 65°F 1939 | -31°F 1932 | 11% | 8% |
| Dec 12 | 38°F | 13°F | 60°F 1939 | -20°F 1949 | 11% | 8% |
| Dec 13 | 37°F | 12°F | 60°F 1933 | -26°F 1926 | 11% | 8% |
| Dec 14 | 37°F | 12°F | 59°F 2021 | -31°F 1926 | 11% | 8% |
| Dec 15 | 37°F | 12°F | 59°F 2025 | -26°F 1926 | 11% | 8% |
| Dec 16 | 37°F | 12°F | 61°F 1962 | -22°F 1914 | 11% | 8% |
| Dec 17 | 37°F | 12°F | 65°F 1939 | -25°F 1924 | 11% | 8% |
| Dec 18 | 37°F | 11°F | 56°F 2024 | -38°F 1924 | 11% | 8% |
| Dec 19 | 37°F | 11°F | 60°F 2025 | -38°F 1924 | 11% | 8% |
| Dec 20 | 37°F | 11°F | 58°F 1957 | -30°F 1924 | 11% | 8% |
| Dec 21 | 36°F | 11°F | 58°F 1994 | -35°F 1990 | 11% | 8% |
| Dec 22 | 36°F | 11°F | 64°F 2025 | -35°F 1990 | 11% | 8% |
| Dec 23 | 36°F | 11°F | 65°F 1933 | -29°F 2022 | 10% | 8% |
| Dec 24 | 36°F | 11°F | 68°F 2025 | -27°F 1924 | 10% | 8% |
| Dec 25 | 36°F | 11°F | 64°F 2025 | -20°F 1962 | 10% | 8% |
| Dec 26 | 36°F | 11°F | 56°F 1959 | -15°F 1948 | 10% | 8% |
| Dec 27 | 36°F | 11°F | 57°F 1955 | -26°F 1916 | 10% | 8% |
| Dec 28 | 36°F | 11°F | 56°F 1999 | -29°F 1916 | 10% | 8% |
| Dec 29 | 36°F | 11°F | 56°F 1999 | -25°F 1990 | 10% | 8% |
| Dec 30 | 37°F | 11°F | 62°F 1933 | -33°F 1990 | 10% | 8% |
| Dec 31 | 37°F | 11°F | 58°F 1996 | -34°F 1923 | 10% | 8% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MST).
- December 1
- sunrise 7:27 AM, sunset 4:37 PM
- December 31
- sunrise 7:46 AM, sunset 4:46 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00488875 (Thermopolis), public domain. Records: NOAA GHCN-Daily, station USC00488875, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.