Seattle Climate by Month – Rainy Season, Temperature Averages
Summary
The climate figures for Seattle are averaged from 2016–2025 observations (10 years). Annual rainfall averages about 1,178 mm.
The rainy season runs January–December. The wettest month is December with 183.9 mm across 19 rain days; the driest is July at just 13.6 mm.
The hottest month is August (average high 24.8°C) and the coolest is December (7.7°C).
The most comfortable time to visit Seattle is July — less rain and milder heat.
Monthly averages · 2016–2025
| Monthly averages | High | Low | Rainfall | Rainy season |
|---|---|---|---|---|
| January | 7.9° | 2.6° | 176 mm | 18 |
| February | 7.9° | 2.3° | 125 mm | 15 |
| March | 10.9° | 3.7° | 108 mm | 16 |
| April | 13.8° | 6.1° | 84 mm | 14 |
| May | 17.9° | 9.4° | 55 mm | 11 |
| June | 20.9° | 12.1° | 51 mm | 8 |
| July | 24.6° | 14.5° | 14 mm | 3 |
| August | 24.8° | 15.1° | 26 mm | 5 |
| September | 20.7° | 13.0° | 63 mm | 10 |
| October | 14.9° | 8.8° | 124 mm | 14 |
| November | 10.5° | 5.7° | 169 mm | 18 |
| December | 7.7° | 3.3° | 184 mm | 19 |