Seattle weather in December
Seattle in December averages 5°C (41°F) and 147 mm of rain.
Of the twelve months in Seattle, December is the coldest and the third wettest.
- Average temp
- 5°C (41°F)
3–8°C · 37–46°F
- Rainfall
- 147 mm
Showers likely
- Sunshine
- —
- Wind
- 14 km/h
What is Seattle like in December?
Daytime
Days are cool.
Rain
Some rain is likely; pack for showers.
Evening
Evenings are cooler. A layer helps after sunset.
What should I pack for Seattle in December?
A light rain jacket
About 147 mm falls this month — showers rather than washouts.
A warm mid-layer
Nights drop to around 3°C (37°F).
December compared with November and January
December in Seattle is 2.4°C cooler than November and 13 mm drier than it, which averages 8°C (46°F).
December in Seattle is 0.5°C cooler than January and about as wet as it, which averages 6°C (42°F).
Daylight in Seattle in December
On 15 December the sun is up for 8 hours 27 minutes in Seattle, rising about 07:51 and setting about 16:18 local time.
December ends 12 minutes shorter than it begins, so the last week of the month is a different length of day from the first.
No month in Seattle has less daylight than December.
Where to stay in Seattle
Dates are a starting point for December.
Travel guides for Seattle
What to read before you book.
Seattle weather by month
TemperatureRainfall
How December compares with the rest of the year
December is highlighted. Every other month links to its own page.
| Month | Average | Rainfall |
|---|---|---|
| January | 6°C / 42°F | 147 mm |
| February | 6°C / 43°F | 96 mm |
| March | 8°C / 46°F | 106 mm |
| April | 10°C / 51°F | 81 mm |
| May | 14°C / 57°F | 48 mm |
| June | 16°C / 62°F | 37 mm |
| July | 19°C / 67°F | 15 mm |
| August | 19°C / 67°F | 25 mm |
| September | 17°C / 62°F | 41 mm |
| October | 12°C / 53°F | 99 mm |
| November | 8°C / 46°F | 160 mm |
| December | 5°C / 41°F | 147 mm |
Check another month
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FAQs about Seattle in December
December climate averages for Seattle, 1991–2020.
Seattle averages 5°C (41°F) in December, ranging from about 3°C (37°F) at night to 8°C (46°F) in the afternoon. That is a 1991–2020 average, so an individual week can run either side of it.
Some. About 147 mm falls across December, enough to need a light jacket but not enough to reshape a trip.
No. December averages 5°C (41°F) against 6°C (42°F) in January — 0.5°C cooler.
December is 2.4°C cooler than November, and 13 mm drier.
It is outside the easiest window. The most comfortable stretch here is May to October; December sits outside it, which usually means more heat, more rain, or both — worth it if you would rather have the place to yourself.
This page does not show today's weather. It is a 1991–2020 climate normal from Meteostat — a long-run average of what December is usually like, which is what you want when booking months ahead. For today or the coming week, check a live forecast.
About 8 hours 27 minutes of daylight in mid-December, the least of any month in Seattle.
On 15 December, sunrise is about 07:51 and sunset about 16:18 local time. Both shift across the month — the month ends 12 minutes shorter than it starts.
