December weather in Gillette, WY
The average temperature in Gillette in December is 25.9°F (16.1°F–35.8°F). Average precipitation: 0.64 inches. Average snowfall is 8.4 inches.
December is a winter month in Gillette, and is cooler than the annual average of 46.8°F. Daily temperatures swing about 19.7°F between overnight low and afternoon high. Expect about 7 days with precipitation. Daylight averages about 8h 41m. For travel, December is cold.
Avg High
35.8°F
Avg Low
16.1°F
Precipitation
0.64 in
Snow
8.4 in
December records in Gillette
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 72.0°F (2021) | -18.9°F (1985) | 0.52 in (1980) |
| December 2 | 64.9°F (2021) | -24.0°F (1985) | 0.54 in (1982) |
| December 3 | 63.0°F (1941) | -6.0°F (1978) | 0.27 in (1927) |
| December 4 | 64.0°F (1965) | -9.9°F (1972) | 0.40 in (1983) |
| December 5 | 69.1°F (1939) | -26.0°F (1972) | 0.21 in (1978) |
| December 6 | 69.1°F (1939) | -27.0°F (1972) | 0.21 in (1986) |
| December 7 | 60.1°F (2024) | -27.0°F (1972) | 0.28 in (1916) |
| December 8 | 64.9°F (1939) | -27.9°F (1972) | 0.27 in (1926) |
| December 9 | 64.0°F (2020) | -29.0°F (1977) | 0.20 in (1997) |
| December 10 | 66.0°F (1981) | -20.0°F (1932) | 0.60 in (1909) |
| December 11 | 59.0°F (1980) | -22.0°F (1932) | 0.60 in (1909) |
| December 12 | 63.0°F (2014) | -22.0°F (1932) | 0.35 in (1926) |
| December 13 | 60.1°F (2014) | -22.0°F (1926) | 0.75 in (1935) |
| December 14 | 61.0°F (1924) | -23.1°F (1926) | 0.37 in (1996) |
| December 15 | 61.0°F (2025) | -16.1°F (1945) | 0.30 in (1942) |
| December 16 | 61.0°F (1939) | -27.0°F (1964) | 0.44 in (1981) |
| December 17 | 61.0°F (1980) | -31.0°F (1964) | 1.15 in (1908) |
| December 18 | 63.0°F (1979) | -31.0°F (1924) | 0.30 in (1973) |
| December 19 | 59.0°F (1979) | -23.1°F (1990) | 0.40 in (1994) |
| December 20 | 60.1°F (1954) | -29.9°F (1990) | 0.30 in (1905) |
| December 21 | 61.0°F (2024) | -33.0°F (1990) | 0.50 in (1911) |
| December 22 | 60.1°F (1954) | -36.0°F (1990) | 0.50 in (1915) |
| December 23 | 60.1°F (1933) | -29.9°F (1983) | 0.20 in (1939) |
| December 24 | 64.9°F (2025) | -36.9°F (1983) | 0.80 in (1982) |
| December 25 | 62.1°F (2025) | -27.9°F (1983) | 0.30 in (2016) |
| December 26 | 55.0°F (1972) | -26.0°F (1996) | 0.60 in (1943) |
| December 27 | 57.0°F (1980) | -13.0°F (1924) | 0.35 in (2003) |
| December 28 | 55.9°F (2002) | -22.0°F (1990) | 0.33 in (1955) |
| December 29 | 60.1°F (1929) | -35.0°F (1990) | 0.30 in (1922) |
| December 30 | 54.0°F (1929) | -33.0°F (1990) | 0.60 in (1915) |
| December 31 | 52.0°F (1963) | -29.9°F (1927) | 0.62 in (2018) |