January weather in SeaTac, WA
The average temperature in SeaTac in January is 42.8°F (37.7°F–48.0°F). Average precipitation: 5.78 inches. Average snowfall is 1.8 inches.
January is a winter month in SeaTac, and is cooler than the annual average of 53.7°F. Daily temperatures swing about 10.3°F between overnight low and afternoon high. Expect about 19 days with precipitation. Daylight averages about 8h 39m. For travel, January is a wet month.
Avg High
48.0°F
Avg Low
37.7°F
Precipitation
5.78 in
Snow
1.8 in
January records in SeaTac
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| January 1 | 57.9°F (2006) | 10.0°F (1952) | 1.37 in (1964) |
| January 2 | 55.9°F (2003) | 6.1°F (1950) | 1.77 in (2007) |
| January 3 | 62.1°F (2020) | 6.1°F (1950) | 1.01 in (1978) |
| January 4 | 61.0°F (1984) | 14.0°F (1950) | 1.56 in (1967) |
| January 5 | 59.0°F (2023) | 15.1°F (1982) | 1.33 in (2006) |
| January 6 | 57.0°F (2002) | 14.0°F (1982) | 2.00 in (2022) |
| January 7 | 59.0°F (2002) | 19.0°F (1973) | 2.29 in (2009) |
| January 8 | 54.0°F (1953) | 18.0°F (1949) | 1.13 in (1959) |
| January 9 | 55.9°F (2003) | 12.9°F (1949) | 2.83 in (1990) |
| January 10 | 59.0°F (1981) | 12.0°F (1949) | 0.94 in (2006) |
| January 11 | 61.0°F (2019) | 12.0°F (1963) | 1.70 in (2022) |
| January 12 | 59.0°F (1986) | 12.9°F (1963) | 2.33 in (2021) |
| January 13 | 57.9°F (2018) | 10.9°F (1950) | 1.63 in (1970) |
| January 14 | 59.0°F (1968) | 8.1°F (1950) | 1.61 in (1988) |
| January 15 | 64.0°F (2018) | 15.1°F (1950) | 1.68 in (1996) |
| January 16 | 55.9°F (2018) | 12.9°F (1950) | 1.78 in (1958) |
| January 17 | 57.0°F (2019) | 15.1°F (1950) | 2.39 in (2005) |
| January 18 | 60.1°F (2005) | 9.0°F (1950) | 2.98 in (1986) |
| January 19 | 62.1°F (2005) | 18.0°F (1954) | 2.26 in (1967) |
| January 20 | 64.0°F (1981) | 16.0°F (1954) | 1.66 in (1972) |
| January 21 | 62.1°F (1981) | 12.9°F (1962) | 1.64 in (1954) |
| January 22 | 60.1°F (1981) | 19.0°F (1962) | 1.29 in (1953) |
| January 23 | 55.9°F (2001) | 16.0°F (1949) | 1.36 in (1959) |
| January 24 | 57.9°F (1995) | 10.0°F (1950) | 1.36 in (1984) |
| January 25 | 63.0°F (2015) | 7.0°F (1950) | 0.93 in (1993) |
| January 26 | 61.0°F (2015) | 9.0°F (1957) | 1.03 in (1950) |
| January 27 | 57.9°F (1952) | 10.9°F (1957) | 1.61 in (1967) |
| January 28 | 61.0°F (2024) | 7.0°F (1950) | 1.23 in (1960) |
| January 29 | 61.0°F (2024) | 6.1°F (1950) | 1.63 in (2004) |
| January 30 | 61.0°F (2024) | 7.0°F (1950) | 1.00 in (1952) |
| January 31 | 61.0°F (1960) | 0.0°F (1950) | 1.93 in (1987) |