Average annual temperature is 21.8 °C
Absolute maximum temperature: 41.8 °C
Absolute minimum temperature: -1.5 °C
Number of sunny days: 174 days
Number of rainy days: 191 days
Look at detailed online map of San Marcos
* Weather data for San Marcos 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) | 26.8 | 30.3 | 33.0 | 34.3 | 32.6 | 39.2 | 39.5 | 41.8 | 39.2 | 34.7 | 27.9 | 25.0 |
| Average daytime temperature (°C) | 19.2 | 20.1 | 25.4 | 25.7 | 28.6 | 34.9 | 36.9 | 39.3 | 35.3 | 27.8 | 19.9 | 19.5 |
| Average temperature (°C) | 13.8 | 13.4 | 18.7 | 19.4 | 23.2 | 28.6 | 30.9 | 32.6 | 29.5 | 22.3 | 15.1 | 13.6 |
| Average night temperature (°C) | 9.5 | 9.1 | 14.1 | 14.8 | 19.0 | 23.2 | 25.1 | 26.0 | 24.1 | 17.8 | 11.5 | 9.2 |
| Absolute minimum temperature (°C) | -1.5 | -0.9 | 5.6 | 9.4 | 13.9 | 18.6 | 22.9 | 23.8 | 21.7 | 5.3 | 4.3 | 2.7 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 10.0 | 11.0 | 12.0 | 13.0 | 13.0 | 14.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 10.0 |
| Daylight mean duration (h) | 10.5 | 11.1 | 12.0 | 12.9 | 13.7 | 14.0 | 13.9 | 13.2 | 12.3 | 11.4 | 10.7 | 10.3 |
| 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) | 7.1 | 7.5 | 6.8 | 7.5 | 8.7 | 11.5 | 12.1 | 12.0 | 10.4 | 8.2 | 6.0 | 7.4 |
| Precipitation (mm) | 75 | 65 | 78 | 215 | 191 | 39 | 15 | 3 | 45 | 145 | 58 | 57 |
| Sunny days | 18 | 15 | 8 | 7 | 2 | 13 | 21 | 25 | 14 | 15 | 16 | 20 |
| Rainy days | 13 | 13 | 23 | 23 | 29 | 17 | 10 | 6 | 16 | 16 | 14 | 11 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit San Marcos during the most sunny months:
The largest precipitation sum in San Marcos is at