Average annual temperature is 20.5 °C
Absolute maximum temperature: 36.8 °C
Absolute minimum temperature: -0.5 °C
Number of sunny days: 151 days
Number of rainy days: 214 days
Look at detailed online map of San Marcos (historical)
* Weather data for San Marcos (historical) 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) | 23.6 | 28.0 | 28.7 | 28.1 | 33.8 | 35.5 | 34.5 | 36.8 | 33.1 | 30.5 | 28.9 | 23.0 |
| Average daytime temperature (°C) | 19.1 | 22.3 | 23.0 | 25.9 | 28.8 | 30.8 | 32.3 | 33.8 | 30.4 | 26.6 | 21.5 | 18.0 |
| Average temperature (°C) | 13.6 | 16.6 | 17.8 | 20.3 | 22.8 | 25.4 | 27.1 | 28.0 | 24.7 | 20.5 | 15.7 | 13.0 |
| Average night temperature (°C) | 9.4 | 12.6 | 13.5 | 15.8 | 17.7 | 21.2 | 23.6 | 23.8 | 20.4 | 15.6 | 11.3 | 9.2 |
| Absolute minimum temperature (°C) | -0.5 | 2.7 | 1.7 | 9.4 | 11.6 | 17.6 | 21.4 | 22.0 | 16.3 | 8.9 | 1.9 | -0.3 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 10.0 | 11.0 | 12.0 | 13.0 | 13.0 | 14.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 10.0 |
| Daylight mean duration (h) | 10.4 | 11.1 | 12.0 | 12.9 | 13.7 | 14.1 | 13.9 | 13.2 | 12.3 | 11.4 | 10.6 | 10.2 |
| Daylight minimum duration (h) | 10.0 | 10.0 | 11.0 | 12.0 | 13.0 | 13.0 | 13.0 | 12.0 | 11.0 | 11.0 | 10.0 | 10.0 |
| Sunshine mean duration (h) | 7.4 | 8.1 | 9.2 | 9.7 | 11.3 | 10.7 | 10.9 | 11.1 | 9.8 | 9.8 | 7.2 | 6.7 |
| Precipitation (mm) | 136 | 94 | 89 | 114 | 113 | 271 | 223 | 171 | 118 | 45 | 74 | 254 |
| Sunny days | 19 | 16 | 14 | 8 | 10 | 3 | 1 | 1 | 13 | 23 | 22 | 21 |
| Rainy days | 12 | 12 | 17 | 22 | 21 | 27 | 30 | 30 | 17 | 8 | 8 | 10 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The largest precipitation sum in San Marcos (historical) is at