Olympia (WA) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Olympia (WA). The numbers are calculated over a 30-year period to provide a reliable average. Let's now guide you through the details for a complete overview.

Olympia has a relatively rain/snowy climate with high precipitation levels, averaging 1414 mm of rain/snowfall annually.

Monthly Precipitation Levels

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

The climate in Olympia shows significant variation throughout the year. Expect 248 mm of precipitation during the wettest month November, distributed over 21 rainy days.

In contrast, July offers drier and sunnier days, with around 16 mm of rainfall over 4 rainy days.

November, the city’s wettest month, has a maximum daytime temperature of 11°C. During the driest month July you can expect a temperature of 25°C. For more detailed insights into the city’s temperatures, visit our Olympia 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

Olympia’s average annual precipitation is 1414 mm. Let’s compare this to some popular worldwide tourist destinations:

Chicago, USA, sees an annual precipitation of 1062 mm, with rain and snow contributing to its humid climate.

Meanwhile, Buenos Aires, Argentina, enjoys a humid subtropical climate with 1000 mm of annual rainfall, mostly in the summer.

Adelaide, Australia, enjoys 511 mm of annual precipitation, with dry summers and wet winters.

Mumbai, India, experiences a tropical monsoon climate with 1860 mm of annual rainfall, with the majority of precipitation happening during the monsoon season from June to September.

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 Olympia (WA)’s weather, including sunshine hours, humidity levels, and temperature data, visit our Olympia (WA) Climate page.