Sunnyvale (CA) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Sunnyvale (CA). The numbers are calculated over a 30-year period to provide a reliable average. Now, let’s explore all the details to give you a full picture.

Sunnyvale tends toward drier weather patterns, receiving approximately 323 mm of rain per year.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm)

The seasons in Sunnyvale, bring significant changes in precipitation. The wettest month, December, receives moderate rainfall, with an average of 70 mm of precipitation.

This rainfall is distributed across 11 rainy days. In contrast, the driest month, July, experiences much less rainfall, totaling 0 mm over 0 rainy days. These distinct seasonal differences provide diverse experiences throughout the year.

December, the city’s wettest month, has a maximum daytime temperature of 15°C and receives 160 hours of sunshine. During the driest month July you can expect a temperature of 26°C. For more detailed insights into the city’s temperatures, visit our Sunnyvale Temperature page.

Annual Precipitation in the United States of America

The map below shows the annual precipitation across the United States of America. You can also select the different months in case you are interested in a specific month.

Amsterdam Precipitation Compared World Wide

Sunnyvale’s average annual precipitation is 323 mm. Let’s compare this to some popular worldwide tourist destinations:

Seville, Spain, experiences 541 mm of rainfall annually, with wet winters and dry summers typical of southern Spain.

In Shanghai, China, the annual average precipitation is 1347 mm, with a humid subtropical climate.

Perth, Australia, receives 565 mm of rainfall annually, mostly during the winter months.

Ho Chi Minh City, Vietnam, receives 1955 mm of annual rainfall, with a pronounced wet season from May to November, typical of its tropical monsoon climate.

How is Precipitation Measured?

Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.

Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.

Interesting weather facts

• The U.S. has a significant number of thunderstorms every year, with over 14.6 million taking place across the world annually.
• Approximately 70% of lightning bolts strike land rather than oceans.
• A storm named John was the longest-lasting Pacific tropical storm, continuing for 31 days. As it crossed the dateline twice, it changed status from a hurricane to a typhoon and back to a hurricane.

For more detailed information about Sunnyvale (CA)’s weather, including sunshine hours, humidity levels, and temperature data, visit our Sunnyvale (CA) Climate page.