San Bernardino Weather & Climate: Best Time to Visit

In San Bernardino, temperatures differ significantly between summer and winter months. Average maximum daytime temperatures range from a pleasant 18°C (64°F) in July, the warmest time of the year, to a very cold -3°C (27°F) during cooler months like January.

At night, you can expect temperatures ranging from 8°C (46°F) in July to around -11°C (12°F) during January.

Check out our detailed temperature page for more information.

Temperature ranges by month

San Bernardino experiences significant rain/snowfall throughout the year, averaging 1593 mm (63 in) of precipitation annually. Significant seasonal changes in precipitation occur throughout the year. In the wettest month, June it receives heavy rainfall, averaging 174 mm (6.9 in) of precipitation, recorded across 19 rainy days. In contrast, the driest month February brings less snowfall, with 77 mm (3 in) over 15 snowy days. For more details, please visit our San Bernardino Precipitation page.

The mean monthly precipitation over the year, including rain, hail, and snow

The average number of days each month with precipitation

Seasonal changes in sunshine hours are quite dramatic in San Bernardino. While July receives considerable daily sunshine with up to 6.5 hours, December marks the darkest time of the year, where sunshine is scarce with only 2.4 hours of sunlight per day.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Daily hours of sunshine

Daily percentage of sunshine

The relative humidity is high throughout the year in San Bernardino.

The city experiences its highest humidity in September, reaching 75%. In April, the humidity drops to its lowest level at 66%. What does this mean? Read our detailed page on humidity levels for further details.

Relative humidity over the year