December weather in Dillon, MT
The average temperature in Dillon in December is 22.4°F (13.2°F–31.6°F). Average precipitation: 0.45 inches. Average snowfall is 4.6 inches.
December is a winter month in Dillon, and is cooler than the annual average of 42.8°F. Daily temperatures swing about 18.4°F between overnight low and afternoon high. Expect about 5 days with precipitation. Daylight averages about 8h 34m. For travel, December is cold.
Avg High
31.6°F
Avg Low
13.2°F
Precipitation
0.45 in
Snow
4.6 in
December records in Dillon
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 60.1°F (2021) | -15.0°F (1985) | 0.42 in (1919) |
| December 2 | 62.1°F (2021) | -13.0°F (1919) | 0.45 in (1917) |
| December 3 | 61.0°F (1969) | -9.0°F (1978) | 0.53 in (1998) |
| December 4 | 57.9°F (1939) | -15.0°F (1909) | 0.55 in (1998) |
| December 5 | 64.0°F (1939) | -27.0°F (1972) | 1.00 in (2025) |
| December 6 | 57.9°F (1900) | -24.0°F (1972) | 0.35 in (1982) |
| December 7 | 57.0°F (1939) | -26.0°F (1972) | 0.42 in (1919) |
| December 8 | 57.9°F (1990) | -27.0°F (1919) | 0.34 in (1906) |
| December 9 | 64.9°F (1939) | -32.1°F (1972) | 0.25 in (1997) |
| December 10 | 62.1°F (1939) | -25.1°F (1932) | 0.70 in (1919) |
| December 11 | 57.9°F (2025) | -33.0°F (1932) | 0.45 in (1903) |
| December 12 | 57.9°F (1924) | -20.9°F (1922) | 0.60 in (1925) |
| December 13 | 60.1°F (1924) | -20.9°F (1963) | 0.45 in (1906) |
| December 14 | 59.0°F (2025) | -22.0°F (1922) | 0.50 in (1927) |
| December 15 | 57.9°F (1980) | -25.1°F (2008) | 0.50 in (1921) |
| December 16 | 57.9°F (1939) | -23.1°F (2008) | 0.51 in (1927) |
| December 17 | 57.9°F (1980) | -29.0°F (2016) | 0.25 in (1924) |
| December 18 | 57.0°F (1979) | -33.0°F (1924) | 0.40 in (1903) |
| December 19 | 55.9°F (1917) | -20.0°F (1990) | 0.63 in (1925) |
| December 20 | 52.0°F (1906) | -23.1°F (1990) | 0.40 in (1895) |
| December 21 | 55.0°F (1969) | -34.1°F (1990) | 0.36 in (1941) |
| December 22 | 57.9°F (1933) | -36.9°F (1990) | 0.25 in (1901) |
| December 23 | 52.0°F (1906) | -33.0°F (1983) | 0.97 in (1955) |
| December 24 | 53.1°F (1906) | -35.0°F (1983) | 0.70 in (2019) |
| December 25 | 52.0°F (2025) | -24.0°F (1944) | 0.45 in (1936) |
| December 26 | 63.0°F (1980) | -20.9°F (1916) | 0.55 in (1971) |
| December 27 | 61.0°F (1980) | -20.9°F (1941) | 0.40 in (1934) |
| December 28 | 53.1°F (1956) | -20.9°F (1946) | 0.63 in (1928) |
| December 29 | 53.1°F (1980) | -33.0°F (1978) | 0.29 in (1945) |
| December 30 | 55.0°F (1980) | -32.1°F (1978) | 0.48 in (2010) |
| December 31 | 54.0°F (1980) | -35.0°F (1927) | 0.25 in (1959) |