- San Bernardino ›
- Weather by month
San Bernardino Weather by Month
Average temperatures, rainfall and humidity for San Bernardino, United States, month by month, built from OpenWeather’s historical records. Use it to see what a typical San Bernardino month looks like before you travel — then check the live San Bernardino forecast for the days ahead.
Warmest month
August
35°C average high
Coolest month
January
7°C average low
Wettest month
February
48 mm of rain
Driest month
June
2 mm of rain
Average temperature and rainfall in San Bernardino by month
Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.
| Month | Avg high | Avg low | Record low / high | Rainfall | Humidity | Wind |
|---|---|---|---|---|---|---|
| January | 19°C | 7°C | -13°C / 29°C | 44 mm | 53% | 7 km/h |
| February | 20°C | 7°C | -8°C / 33°C | 48 mm | 54% | 7 km/h |
| March | 22°C | 8°C | -7°C / 38°C | 37 mm | 57% | 8 km/h |
| April | 24°C | 10°C | -5°C / 35°C | 15 mm | 53% | 9 km/h |
| May | 26°C | 13°C | 1°C / 38°C | 19 mm | 56% | 9 km/h |
| June | 31°C | 16°C | 4°C / 43°C | 2 mm | 50% | 8 km/h |
| July | 35°C | 20°C | 9°C / 45°C | 6 mm | 46% | 8 km/h |
| August | 35°C | 20°C | 8°C / 42°C | 6 mm | 46% | 8 km/h |
| September | 32°C | 18°C | 5°C / 47°C | 9 mm | 49% | 7 km/h |
| October | 28°C | 13°C | -2°C / 40°C | 10 mm | 47% | 7 km/h |
| November | 23°C | 9°C | -6°C / 34°C | 18 mm | 46% | 7 km/h |
| December | 19°C | 7°C | -10°C / 30°C | 48 mm | 54% | 6 km/h |
Best time to visit San Bernardino
The most comfortable time to visit San Bernardino is generally April to May and November, balancing mild daytime temperatures against the driest stretch of the year. The city has a moderate seasonal swing and rain concentrates around February, totalling about 260 mm a year.
Travellers who prefer heat should aim for August, when highs average 35°C. February is the month to avoid if rain would spoil your plans — it averages 48 mm, roughly 29× the rainfall of the driest month (June).
Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the San Bernardino forecast for what is happening now.