December weather in Mountlake Terrace, WA
The average temperature in Mountlake Terrace in December is 41.8°F (37.0°F–46.5°F). Average precipitation: 5.55 inches. Average snowfall is 1.7 inches.
December is a winter month in Mountlake Terrace, and is cooler than the annual average of 53.2°F. Daily temperatures swing about 9.5°F between overnight low and afternoon high. Expect about 20 days with precipitation. Daylight averages about 8h 13m. For travel, December is a wet month.
Avg High
46.5°F
Avg Low
37.0°F
Precipitation
5.55 in
Snow
1.7 in
December records in Mountlake Terrace
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 59.0°F (2008) | 26.2°F (2014) | 1.28 in (1987) |
| December 2 | 57.9°F (1997) | 28.2°F (2014) | 1.48 in (2007) |
| December 3 | 57.9°F (1993) | 27.0°F (1992) | 4.15 in (2007) |
| December 4 | 57.9°F (1989) | 23.0°F (1994) | 1.51 in (2023) |
| December 5 | 59.0°F (2020) | 24.3°F (2013) | 1.88 in (2023) |
| December 6 | 55.0°F (2015) | 24.3°F (2013) | 0.93 in (1987) |
| December 7 | 57.0°F (2025) | 20.1°F (2013) | 0.84 in (2024) |
| December 8 | 57.9°F (2014) | 18.1°F (2013) | 1.51 in (2015) |
| December 9 | 61.0°F (2014) | 17.1°F (2009) | 1.34 in (1987) |
| December 10 | 64.9°F (2014) | 19.0°F (2009) | 1.46 in (1992) |
| December 11 | 57.0°F (2014) | 23.0°F (2009) | 1.23 in (2006) |
| December 12 | 60.1°F (1995) | 25.0°F (2009) | 2.25 in (2010) |
| December 13 | 57.0°F (2010) | 28.0°F (1994) | 0.88 in (2001) |
| December 14 | 57.0°F (2002) | 25.0°F (2008) | 2.17 in (2006) |
| December 15 | 59.0°F (2025) | 23.0°F (2008) | 0.81 in (2025) |
| December 16 | 55.9°F (2025) | 19.9°F (2008) | 1.27 in (2001) |
| December 17 | 54.0°F (1994) | 24.3°F (2016) | 1.25 in (1994) |
| December 18 | 55.9°F (2003) | 23.0°F (1990) | 0.86 in (1990) |
| December 19 | 55.0°F (1994) | 19.0°F (1990) | 1.53 in (1994) |
| December 20 | 57.0°F (2009) | 12.0°F (1990) | 2.64 in (2019) |
| December 21 | 55.9°F (2020) | 10.0°F (1990) | 2.19 in (2020) |
| December 22 | 55.0°F (1995) | 17.1°F (1990) | 0.92 in (2023) |
| December 23 | 57.0°F (2024) | 17.1°F (1990) | 1.09 in (2014) |
| December 24 | 55.9°F (2005) | 25.0°F (1990) | 1.14 in (2022) |
| December 25 | 55.0°F (2005) | 25.0°F (1995) | 1.08 in (2022) |
| December 26 | 55.9°F (2022) | 22.1°F (2021) | 1.35 in (2006) |
| December 27 | 57.0°F (1994) | 17.2°F (2021) | 0.81 in (2022) |
| December 28 | 55.9°F (2023) | 14.0°F (1990) | 0.95 in (1986) |
| December 29 | 64.0°F (2023) | 10.9°F (1990) | 2.67 in (1996) |
| December 30 | 53.1°F (1991) | 23.0°F (1990) | 0.79 in (2005) |
| December 31 | 54.0°F (2019) | 22.1°F (2021) | 1.38 in (1996) |