December weather in Index, WA
The average temperature in Index in December is 36.2°F (31.6°F–40.8°F). Average precipitation: 14.56 inches. Average snowfall is 17.0 inches.
December is a winter month in Index, and is cooler than the annual average of 49.8°F. Daily temperatures swing about 9.2°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
40.8°F
Avg Low
31.6°F
Precipitation
14.56 in
Snow
17.0 in
December records in Index
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 60.1°F (2002) | 15.1°F (1985) | 3.77 in (1977) |
| December 2 | 60.1°F (2002) | 21.0°F (1985) | 5.24 in (1975) |
| December 3 | 55.9°F (1977) | 23.0°F (2014) | 7.54 in (1982) |
| December 4 | 54.0°F (1975) | 0.0°F (1995) | 5.71 in (1989) |
| December 5 | 54.0°F (1991) | 16.0°F (1972) | 3.02 in (1991) |
| December 6 | 55.0°F (2020) | 15.1°F (1972) | 2.98 in (1970) |
| December 7 | 52.0°F (2017) | 3.0°F (1972) | 1.76 in (2012) |
| December 8 | 52.0°F (2017) | 1.0°F (1972) | 2.73 in (2015) |
| December 9 | 55.0°F (2015) | 6.1°F (1972) | 5.61 in (2015) |
| December 10 | 57.0°F (2014) | 10.9°F (1972) | 3.01 in (1977) |
| December 11 | 51.1°F (2014) | 10.9°F (1972) | 3.71 in (2004) |
| December 12 | 52.0°F (2014) | 12.9°F (1972) | 5.90 in (2010) |
| December 13 | 55.0°F (1988) | 7.0°F (1972) | 2.90 in (2001) |
| December 14 | 55.0°F (1977) | 21.0°F (1972) | 3.79 in (1979) |
| December 15 | 51.1°F (1979) | 19.0°F (2008) | 3.54 in (1979) |
| December 16 | 51.1°F (1999) | 14.0°F (2008) | 4.49 in (1997) |
| December 17 | 53.1°F (2004) | 17.1°F (2008) | 3.49 in (1979) |
| December 18 | 48.9°F (2004) | 14.0°F (1984) | 2.83 in (2017) |
| December 19 | 55.9°F (2004) | 8.1°F (2008) | 2.11 in (1994) |
| December 20 | 52.0°F (2003) | 3.9°F (1990) | 6.20 in (2019) |
| December 21 | 54.0°F (1972) | 1.0°F (1990) | 3.71 in (1974) |
| December 22 | 53.1°F (1980) | 3.9°F (1983) | 2.12 in (1992) |
| December 23 | 50.0°F (1999) | 1.0°F (1983) | 2.05 in (1972) |
| December 24 | 48.0°F (2003) | 10.0°F (1983) | 2.89 in (2005) |
| December 25 | 55.9°F (1980) | 19.0°F (1987) | 2.99 in (1980) |
| December 26 | 57.9°F (1980) | 19.9°F (1970) | 3.62 in (1972) |
| December 27 | 57.0°F (1999) | 16.0°F (2021) | 2.39 in (1994) |
| December 28 | 54.0°F (1997) | 10.9°F (1978) | 2.70 in (2011) |
| December 29 | 53.1°F (1998) | 6.1°F (1990) | 5.39 in (1998) |
| December 30 | 50.0°F (1980) | 3.0°F (1978) | 2.80 in (2018) |
| December 31 | 48.9°F (1980) | 7.0°F (1978) | 2.31 in (1996) |