Seattle Weather in December
December in Seattle brings low temperatures around 8°C (46°F) during the day, dropping to 2°C (36°F) at night, with quite a bit of rainfall expected, averaging around 143 mm (5.6 in) for the month.
Rainfall in Seattle in December
You can typically expect 20 days of rain this month, averaging around 143 mm (5.6 in). This month brings frequent, heavy showers. Both the number of wet days and the rainfall totals are on the high side.
Temperature in Seattle in December
In December, expect low temperatures in Seattle, with highs of 8°C (46°F) and lows of 2°C (36°F) at night. The month of December belongs to the winter season. Cold conditions persist throughout the day, so warm clothing is important from the moment you head outside. Nights drop to 2°C (36°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet. The coldest month of the year calls for plenty of warm layers. Be sure to pack your winter gear.
Sunshine in Seattle in December
This month sees fewer sunny days, with about 54 hours of sunshine, perfect for those who enjoy cooler temperatures.
Wind Speed in Seattle in December
December sees wind speeds averaging 4 m/s (8 knots). You'll experience variable conditions with moderate winds that create small waves on water and keep branches moving. Conditions range from light winds to moderate breezes throughout the month.If you prefer dry days with pleasant temperatures, December may not be the ideal month to visit Seattle. Our weather planner can help you explore destinations with more pleasant weather conditions.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Seattle's climate page.
Seattle Temperature in December
Min Temperature
2°C (36°F)
Max Temperature
8°C (46°F)
Chance of Rain
66%
Precipitation
143 mm (5.6 in)
Rainy days
20 days
Humidity
80%
Windspeed
4 m/s (8 knots)
Sunshine
54 hours
Percentage Sunshine
20%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Seattle typically stay consistent throughout December, with daily highs averaging around 8°C (46°F). Nights are cold, with lows around 3°C (37°F).
Average temperatures in December
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in December
Historical weather for Seattle in December
Browse day-by-day weather records for Seattle spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Seattle historical weather extremes in December
According to our 49 years of weather records for Seattle, the following extremes were recorded between 1976 and 2025.
- On December 10, 2014, temperatures climbed to 19°C (66°F), marking the warmest December day on record.
- The coldest December day was on December 21, 1990, with a maximum of -7°C (19°F).
- Seattle registered its coldest December night on December 23, 1983, with temperatures dropping to -12°C (10°F).
Best Places in the United States of America in December
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in December →
perfect weather
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unpleasant
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What to Wear in Seattle in December
Cold weather calls for smart layering in December. A thermal base layer makes a huge difference in staying warm. Add a wool sweater or fleece, then a wind-resistant outer jacket. Prepare for significant rainfall with proper waterproof clothing and shoes. Sunglasses aren't essential this month, though you might want them for the occasional bright moment.What To Do in Seattle in December
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Seattle's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed
See the full Seattle climate overview or explore weather in the United States of America.
