Seattle weather in December
Long-run climate averages for Seattle, WA in December, plus what the forecast models say for the days ahead.
In December, Seattle averages 49°F by day and 40°F at night. It is the wettest month of the year here.
December in Seattle averages a daytime high of 49°F and an overnight low of 40°F, which reads as cool for this part of the world. It is among the three coldest months of the year here. It is also the wettest month, so build rain into any plan. Across the whole year Seattle sees roughly 43 inches of precipitation.
Climate averages tell you what to pack. They do not tell you what next Tuesday looks like — for that, see the live Seattle forecast with every model compared and how much they currently agree.
Seattle weather by month
what to expect in Seattle through the yearHere is Seattle's typical weather in each month: the average daytime high and overnight low in °F, how each month feels, and the wettest month marked. Use it to plan any trip to Seattle by season.