San Francisco Climate by Month – Rainy Season, Temperature Averages
Summary
The climate figures for San Francisco are averaged from 2016–2025 observations (10 years). Annual rainfall averages about 610 mm.
The rainy season runs January–December. The wettest month is December with 132.7 mm across 10 rain days; the driest is July at just 0.3 mm.
The hottest month is September (average high 20.9°C) and the coolest is December (13.5°C).
The most comfortable time to visit San Francisco is July — less rain and milder heat.
Monthly averages · 2016–2025
| Monthly averages | High | Low | Rainfall | Rainy season |
|---|---|---|---|---|
| January | 13.7° | 7.9° | 126 mm | 11 |
| February | 14.6° | 7.9° | 96 mm | 8 |
| March | 14.6° | 9.0° | 103 mm | 11 |
| April | 15.9° | 10.1° | 32 mm | 5 |
| May | 17.2° | 11.3° | 17 mm | 2 |
| June | 18.9° | 12.7° | 1 mm | 0 |
| July | 18.7° | 13.3° | 0 mm | 0 |
| August | 19.7° | 14.2° | 1 mm | 0 |
| September | 20.9° | 14.4° | 4 mm | 1 |
| October | 20.4° | 12.9° | 32 mm | 3 |
| November | 16.5° | 10.1° | 64 mm | 7 |
| December | 13.5° | 8.0° | 133 mm | 10 |