Spokane (WA) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Spokane, Washington State, United States of America. These values are calculated using 30 years of data (1990–2020) to ensure accuracy. Now, let's break down all the details for a clearer picture.

Spokane typically sees modest rain/snowfall throughout the year, with an average annual precipitation of 456 mm (18 in). The city experiences a distinct dry season during certain months, as illustrated in the graph below.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm (0.01 in))

The seasons in Spokane, bring significant changes in precipitation. The wettest month, December, receives moderate snow/rainfall, with an average of 70 mm (2.8 in) of precipitation. This snow/rainfall is distributed across 15 snowy/rainy days.

December, the wettest month, has a maximum daytime temperature of 2°C (36°F). The city receives 60 hours of sunshine in this period. During the driest month July you can expect a temperature of 30°C (86°F). For more detailed insights into the city's temperatures, visit our Spokane Temperature page.

Spokane's average annual precipitation is 456 mm (18 in). Let's compare this to some popular worldwide tourist destinations:

Seville, Spain, experiences 541 mm (21 in) of rainfall annually, with wet winters and dry summers typical of southern Spain.

In Shanghai, China, the annual average precipitation is 1347 mm (53 in), with a humid subtropical climate.

In Tokyo, Japan, the average annual precipitation is 1528 mm (60 in), with significant summer rains due to typhoon season.

Bangkok, Thailand, experiences a tropical monsoon climate with 1668 mm (66 in) of annual rainfall, with the heaviest precipitation occurring during September and October.

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.

Precipitation has a very strong role in determining the local climate and ecosystem:

• Changing Rainfall Patterns: Global warming causes drastic changes in the patterns of rainfall. Some areas have been experiencing increased frequency and intensity of rainfall, while other areas experience longer dry spells or even droughts.
• Local Impacts: Many regions are experiencing heavier rainfall in the winter months and drier, hotter summers. This affects agriculture, water resources, and ecosystems.

• Mawsynram in India is noted as being the wettest place on earth, with over 11 meters (36 feet) of rain falling every year.
• In contrast, Antofagasta in Chile is among the driest places on the planet, getting less than 0.1mm (0.004 inches) per year, with some years recording virtually no rainfall.
• Nearly 1,650 thunderstorm cells are estimated over the planet at any given time.

For more detailed information about Spokane (WA)'s weather, including sunshine hours, humidity levels, and temperature data, visit our Spokane (WA) Climate page.