Hottest (avg)
#12 / 12
Seattle in December
December weather, climate averages, and packing tips.
Avg High
Avg Low
Rain
Daylight 8h
What to expect
As winter continues, December brings, where temperatures are dropping quickly. Daytime highs average 7°C / 44°F, dropping to 2°C / 35°F at night.
Skies are often overcast, and you should be prepared for regular rainfall (approx. 20 wet days). With only around 8.5 hours of daylight, the sun sets early, so plan outdoor activities for the morning or midday.
December in context
How it compares to the rest of the year in Seattle.
Wettest (avg)
#2 / 12
Daylight Hours
#12 / 12
Windiest (avg)
#2 / 12
Highest UV
#12 / 12
Most Humid
#3 / 12
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight
- 8.5 hours
- UV index (max)
- 2
- Typical sun hours
- 07:49 – 16:19
Rain & Snow
- Total
-
- Rainy days
- 20
- Cloud cover
- 78%
- Snowfall
-
Humidity & Wind
- Humidity (avg)
- 84%
- Wind (avg)
-
- Wind (max gusts)
-
Frequently asked questions
Is December a good time to visit Seattle?
Typical December days in Seattle reach highs of 7°C (45°F) with nights around 2°C (36°F). It usually feels chilly by day and very cold after dark. It is among the wetter months, so it is wise to have some indoor backup plans or flexible activities.
What are temperatures like in December?
In December, you can usually expect highs of 7°C (45°F) and lows near 2°C (36°F). That means chilly days and very cold nights, so pack layers you can add or remove.
How much does it rain in December?
Rainfall in December averages 183 mm (7.2 in) across roughly 20 days. Overall it is a very wet time of year, so a light rain jacket and waterproof shoes are very handy.
How many hours of daylight are there in December?
You can expect about 8 hours of daylight in December. Sunrise is typically around 07:49 and sunset near 16:19. Daylight is quite limited, and it can feel like a short-day season.
How strong is the sun in December?
UV levels are usually low (around 2), so standard sun protection is enough.
Is it windy in December?
In December, average wind speeds are around 11 km/h (7 mph), with gusts on the windiest days reaching about 63 km/h (39 mph). On the ground, it is it is a notably windy place, and strong gusts are fairly common.