Santa Rosa Weather & Climate: Best Time to Visit

The climate in Santa Rosa remains fairly constant, offering very warm temperatures throughout the year. Average maximum daytime temperatures range from a very warm 33°C (91°F) in May, the warmest time of the year, to a comfortable 29°C (84°F) during cooler months like January.

At night, you can expect temperatures ranging from 26°C (79°F) in May to around 23°C (73°F) during January.

Check out our detailed temperature page for more information.

Temperature ranges by month

Santa Rosa is known for its substantial rainfall, with annual precipitation reaching 2335 mm (92 in). Significant seasonal changes in precipitation occur throughout the year. In the wettest month, July it receives heavy rainfall, averaging 431 mm (17 in) of precipitation, recorded across 19 rainy days. In contrast, the driest month February brings less rainfall, with 39 mm (1.5 in) over 4 rainy days. For more details, please visit our Santa Rosa 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 Santa Rosa. While April receives considerable daily sunshine with up to 8.7 hours, September marks the darkest time of the year, where sunshine is scarce with only 4.4 hours of sunlight per day.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Daily hours of sunshine

The relative humidity is high throughout the year in Santa Rosa.

The city experiences its highest humidity in September, reaching 82%. In April, the humidity drops to its lowest level at 65%. What does this mean? Read our detailed page on humidity levels for further details.

Relative humidity over the year