December weather in Roslyn, WA
The average temperature in Roslyn in December is 30.1°F (25.0°F–35.2°F). Average precipitation: 7.37 inches.
December is a winter month in Roslyn, and is cooler than the annual average of 45.2°F. Daily temperatures swing about 10.2°F between overnight low and afternoon high. Daylight averages about 8h 17m. For travel, December is a wet month.
Avg High
35.2°F
Avg Low
25.0°F
Precipitation
7.37 in
Daylight
8h 17m
December records in Roslyn
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 57.9°F (2021) | 8.1°F (2014) | 1.68 in (2013) |
| December 2 | 57.9°F (2021) | 12.0°F (2006) | 1.65 in (1932) |
| December 3 | 50.0°F (1932) | 10.0°F (2013) | 0.84 in (2007) |
| December 4 | 48.9°F (1932) | 10.0°F (2013) | 1.57 in (2007) |
| December 5 | 48.0°F (1932) | 7.0°F (2013) | 1.82 in (2023) |
| December 6 | 51.1°F (2008) | 8.1°F (2013) | 1.20 in (1906) |
| December 7 | 54.0°F (2008) | 8.1°F (2009) | 0.74 in (2001) |
| December 8 | 45.0°F (2025) | -4.0°F (2009) | 0.91 in (2025) |
| December 9 | 52.0°F (2025) | -2.0°F (1932) | 4.89 in (2025) |
| December 10 | 48.0°F (2025) | -2.9°F (1932) | 3.31 in (2025) |
| December 11 | 55.9°F (2025) | -6.0°F (1932) | 2.80 in (2025) |
| December 12 | 46.9°F (2014) | -4.0°F (1932) | 1.41 in (2018) |
| December 13 | 48.9°F (2025) | 0.0°F (1932) | 1.94 in (2018) |
| December 14 | 46.0°F (2025) | -0.9°F (1932) | 1.30 in (2001) |
| December 15 | 48.0°F (2013) | 1.0°F (1932) | 1.10 in (1906) |
| December 16 | 52.0°F (2025) | -2.9°F (2008) | 1.50 in (2001) |
| December 17 | 46.0°F (2013) | -2.0°F (2008) | 1.85 in (2025) |
| December 18 | 41.0°F (1934) | 10.0°F (2016) | 1.78 in (2024) |
| December 19 | 46.0°F (2004) | 1.9°F (2008) | 1.99 in (2025) |
| December 20 | 50.0°F (1934) | -6.0°F (2008) | 2.40 in (1934) |
| December 21 | 45.0°F (2014) | 3.0°F (2008) | 2.54 in (2014) |
| December 22 | 48.0°F (2013) | 1.0°F (2022) | 1.28 in (1950) |
| December 23 | 48.0°F (2013) | 1.0°F (2022) | 1.53 in (2005) |
| December 24 | 46.0°F (2004) | 3.9°F (2022) | 1.88 in (2005) |
| December 25 | 46.9°F (2013) | 10.0°F (2022) | 1.00 in (1934) |
| December 26 | 44.1°F (2014) | 12.0°F (2021) | 1.28 in (2007) |
| December 27 | 43.0°F (1932) | 10.0°F (1934) | 1.11 in (2024) |
| December 28 | 50.0°F (2011) | 10.0°F (2021) | 2.23 in (2008) |
| December 29 | 46.9°F (2011) | 9.0°F (2021) | 1.08 in (2011) |
| December 30 | 48.0°F (2018) | 3.9°F (2003) | 1.21 in (2011) |
| December 31 | 46.0°F (2013) | -0.9°F (2010) | 0.83 in (2008) |