Walnut Creek (CA) Weather & Climate: Best Time to Visit

In Walnut Creek, temperatures differ significantly between summer and winter months. Average daytime temperatures reach a comfortable 30°C (86°F) in July. In December, the coolest month of the year, temperatures drop to a moderate 14°C (57°F).

At night, temperatures range from around 14°C (57°F) in July to 4°C (39°F) in December.

Check out our detailed temperature page for more information.

Temperature ranges by month

Walnut Creek tends toward drier weather patterns, receiving approximately 479 mm (19 in) of rain per year. Walnut Creek can be quite wet during December, receiving approximately 102 mm (4 in) of precipitation over 13 rainy days.

In contrast, during the driest month (August), you will experience much drier conditions, with 0.1 mm (0 in) of precipitation spread across 0 rainy days. For more details, please visit our Walnut Creek Precipitation page.

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

The average number of days each month with precipitation

Walnut Creek can be enjoyed more throughout the sunniest month of May under a blue sky, with approximately 10.8 hours of sunshine daily. In contrast, the city experiences much darker days in December, with only 5.3 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 Walnut Creek.

The city experiences its highest humidity in January, reaching 80%. In June, the humidity drops to its lowest level at 71%. What does this mean? Read our detailed page on humidity levels for further details.

Relative humidity over the year