Average annual temperature is 13.2 °C
Absolute maximum temperature: 36.0 °C
Absolute minimum temperature: 0.6 °C
Number of sunny days: 242 days
Number of rainy days: 123 days
Look at detailed online map of San Mateo County
* Weather data for San Mateo County United States is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 17.8 | 20.2 | 20.3 | 28.5 | 29.7 | 29.7 | 35.0 | 34.7 | 28.5 | 36.0 | 26.2 | 21.1 |
| Average daytime temperature (°C) | 13.5 | 14.0 | 13.4 | 17.7 | 18.4 | 20.5 | 26.8 | 27.3 | 23.6 | 25.0 | 19.2 | 16.1 |
| Average temperature (°C) | 9.4 | 8.0 | 8.5 | 11.2 | 12.7 | 14.3 | 18.0 | 18.9 | 16.7 | 16.9 | 12.9 | 11.0 |
| Average night temperature (°C) | 6.3 | 3.8 | 5.0 | 6.6 | 9.1 | 10.4 | 11.7 | 13.7 | 12.1 | 11.6 | 8.3 | 7.6 |
| Absolute minimum temperature (°C) | 1.7 | 0.7 | 0.6 | 2.6 | 5.8 | 7.3 | 9.8 | 11.4 | 8.7 | 5.6 | 3.9 | 3.7 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 14.0 | 14.0 | 14.0 | 12.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 9.9 | 10.8 | 12.0 | 13.2 | 14.2 | 14.7 | 14.5 | 13.6 | 12.4 | 11.2 | 10.2 | 9.6 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 6.2 | 7.8 | 8.0 | 10.9 | 10.7 | 12.2 | 12.8 | 11.9 | 10.8 | 9.4 | 8.2 | 6.2 |
| Precipitation (mm) | 275 | 90 | 242 | 7 | 73 | 0 | 0 | 1 | 5 | 11 | 108 | 150 |
| Sunny days | 11 | 13 | 8 | 22 | 18 | 28 | 30 | 26 | 25 | 26 | 20 | 15 |
| Rainy days | 20 | 15 | 23 | 8 | 13 | 2 | 1 | 5 | 5 | 5 | 10 | 16 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit San Mateo County during the most sunny months:
The largest precipitation sum in San Mateo County is at