Monthly climate guide
Seattle weather in December
December in Seattle is typically cold, with average daytime highs around 7°C (44°F) and night-time lows near 2°C (35°F). The month usually brings about 172 mm of rain (very wet) and is often cloudy. Daytime highs are 3°C cooler than November and about the same as January.
What stands out in December
- Days and nights are close, only about 5°C apart.
- It's wetter than a typical month in Seattle — roughly 59% more rain than average.
- Seattle is usually about 12°C cooler than Phoenix in December.
- Seasonally, December counts as early winter in Seattle.
December is typically Seattle's coolest month.
Avg high
7°C
44°F
Avg low
2°C
35°F
Rainfall
172 mm
very wet
Humidity
91%
relative
Sky
78%
cloud · often cloudy
Seattle weather by month
Show the monthly averages as a table
| Month | Avg high | Avg low | Rain | Humidity | Cloud cover |
|---|---|---|---|---|---|
| January | 7°C / 45°F | 2°C / 35°F | 169 mm | 90% | 79% |
| February | 8°C / 46°F | 2°C / 35°F | 138 mm | 88% | 78% |
| March | 11°C / 51°F | 3°C / 38°F | 155 mm | 85% | 76% |
| April | 14°C / 56°F | 5°C / 41°F | 107 mm | 82% | 75% |
| May | 18°C / 64°F | 9°C / 47°F | 70 mm | 80% | 69% |
| June | 20°C / 68°F | 11°C / 51°F | 51 mm | 80% | 68% |
| July | 23°C / 73°F | 13°C / 56°F | 20 mm | 78% | 47% |
| August | 24°C / 75°F | 14°C / 56°F | 23 mm | 77% | 46% |
| September | 21°C / 69°F | 11°C / 52°F | 65 mm | 79% | 55% |
| October | 15°C / 60°F | 8°C / 46°F | 142 mm | 85% | 68% |
| November | 10°C / 50°F | 4°C / 39°F | 184 mm | 89% | 76% |
| December | 7°C / 44°F | 2°C / 35°F | 172 mm | 91% | 78% |
What to pack for December
- A proper insulated winter coat
- A hat, scarf and gloves
- A compact umbrella or packable rain jacket
- Water-resistant shoes
Is December a good time to visit Seattle?
Compare the months in the chart above to find your ideal window.
Best time to visit Seattle →Other United States cities in December
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Seattle weather in December. WeatherCompare, 2026 (NASA POWER / ERA5, 2011–2020 monthly averages). https://weathercompare.eu/weather/usa/seattle/december
<a href="https://weathercompare.eu/weather/usa/seattle/december">Seattle weather in December</a> (WeatherCompare)
<iframe src="https://weathercompare.eu/embed/usa/seattle" width="300" height="160" style="border:0;border-radius:12px" loading="lazy" title="Seattle weather in December"></iframe> <p style="font-size:12px"><a href="https://weathercompare.eu/weather/usa/seattle/december">Seattle weather in December</a> – WeatherCompare</p>
Seattle in December: quick answers
Is December a good time to visit Seattle?
December is cool in Seattle, with highs around 7°C. Better for museums and city walks than the beach, and usually quieter.
How warm is Seattle in December?
Average highs are about 7°C (44°F) and average lows about 2°C (35°F), based on 10 years of daily data.
Does it rain a lot in Seattle in December?
Seattle typically gets around 172 mm of rain in December — very wet.
Figures are long-term averages for the area around Seattle (NASA POWER / ERA5, 2011–2020), not a forecast for a specific year. For upcoming days, see the live multi-source forecast.