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

This page shows the average amount of rainfall per month in Palo Alto (CA). The numbers are calculated over a 30-year period to provide a reliable average. Let’s explore the details in depth to provide you with a complete overview.

With annual rainfall averaging 351 mm, Palo Alto maintains relatively low precipitation levels throughout the seasons.

Monthly Precipitation Levels

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

The climate in Palo Alto shows significant variation throughout the year. Expect 83 mm of precipitation during the wettest month December, distributed over 12 rainy days.

In contrast, July offers drier and sunnier days, with around 0 mm of rainfall over 0 rainy days.

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 Palo Alto 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

Palo Alto’s average annual precipitation is 351 mm. Let’s compare this to some popular worldwide tourist destinations:

Athens, Greece, receives an average annual precipitation of 400 mm, making it one of the drier Mediterranean climates with rainfall mostly in winter.

Beijing, China, receives 560 mm of annual precipitation, concentrated in the summer months.

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

Bangkok, Thailand, experiences a tropical monsoon climate with 1668 mm of annual rainfall, with the heaviest precipitation occurring during September and October.

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

• "Ginger" was the longest-lasting Atlantic tropical storm, which spun around the open ocean for 28 days in 1971.
• The world's largest snowflake was recorded in the Guinness Book of Records, at 38 cm wide and 20 cm thick. The snowflake fell at Fort Keogh, Montana, USA, on 28 January 1887.
• The greatest snowfall recorded was on Mt. Rainier, Washington State, USA—over 31.5 meters fell during the winter of 1972.

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