Sunnyvale (CA) Weather and Climate: A Comprehensive Guide
The climate in Sunnyvale is marked by big temperature swings throughout the year.
Temperatures range from warm during the warmest months
to mild in the cooler months.
The city tends toward drier weather patterns.
Now, let’s explore all the climate details to give you a full picture.
Average maximum day and minimum night temperature
In Sunnyvale, temperatures differ significantly between summer and winter months. Typically, average maximum daytime temperatures range from a comfortable 27°C in September to a moderate 15°C in the coolest month, January.
Nights are cooler, with lows often dropping to around 5°C during the colder months. Check out our detailed temperature page for more information.Temperature ranges by month
Precipitation and rainy days
Sunnyvale tends toward drier weather patterns, receiving approximately 323 mm of rain per year. The climate in Sunnyvale shows significant variation throughout the year. Expect moderate rainfall in December, with an average of 70 mm of precipitation over 11 rainy days. In contrast, July offers drier and sunnier days, with around 0 mm of rainfall over 0 rainy days. For more details, please visit our Sunnyvale Precipitation page.The mean monthly precipitation over the year, including rain, hail and snow
The average number of days each month with precipitation
Sunshine over the year
For those who appreciate different seasons, Sunnyvale serves as an ideal destination. Expect longer, more sun-filled days in May with an average of 10.8 hours of sunshine daily, and embrace the darker days in December, offering only 5.3 hours of daily sunlight. Visit our detailed sunshine hours page for more information.Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Average humidity
The relative humidity is high throughout the year in Sunnyvale.
The city experiences its highest humidity in January, reaching 80%. In June, the humidity drops to its lowest level at 71%. Explore our detailed page on humidity levels for further details.
Relative humidity over the year
broken clouds and no rain partly cloudy and rain broken clouds and no rainForecast for Sunnyvale (CA)
2 m/s
3 m/s
2 m/s
The best time of year to visit Sunnyvale in the United States of America
During the months of April, May, June and October you are most likely to experience good weather with pleasant average temperatures that fall between 20°C and 26°C.Other facts from our historical weather data:
The hottest season / summer takes place in June, July, August and September.
Yes, the months of May, June, July, August, September and October are very dry.
September has an average maximum temperature of 27°C and is the warmest month of the year.
The coldest month is January with an average maximum temperature of 15°C.
December tops the wettest month list with 70 mm of rainfall.
July is the driest month with 0 mm of precipitation.
May is the sunniest month with an average of 324 hours of sunshine.
No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.
