Rain Stats

Seattle averages 37.49 inches of precipitation a year, with the vast majority falling as rain instead of snow. Official precipitation totals for the city are measured at Sea-Tac Airport, which is actually located south of the Seattle city limits. Regardless, Seattle’s precipitation has been logged there since 1945—with records from 1948 onward now digitized by the National Climatic Data Center. Below are two graphs that, together, show Seattle’s yearly precipitation from 1948 to present. The third chart lists Seattle’s top ten wettest days, with the record-setting rains of Oct. 20, 2003 ranking number one.

55.14 inches of precipitation doused Seattle in 1950—the wettest year on record for the city. Just two years later, however, only a meager 23.78 inches fell—making 1952 the driest year in Seattle’s history.
55.14 inches of precipitation doused Seattle in 1950—the wettest year on record for the city. Just two years later, however, only a meager 23.78 inches fell—making 1952 the driest year in Seattle’s history.

 

In 1996, Seattle topped 50 inches of precipitation for just the third time—good enough for the second-soggiest year on record. By contrast, a mere 25.13 inches was recorded in 1985, making it second only to 1952 in terms of dryness.

 

Seattle had never seen a daily rainfall of 4 inches or more until Oct. 20, 2003, when a torrential 5.02 inches deluged the city--setting a new record for the wettest day in Seattle history. Just four years later, 3.77 inches fell at the height of widespread flooding in Western Washington.
Seattle had never seen a daily rainfall of 4 inches or more until Oct. 20, 2003, when a torrential 5.02 inches deluged the city—setting a new record for the wettest day in Seattle history. Just four years later, 3.77 inches fell at the height of widespread flooding in Western Washington, placing Dec. 3, 2007 second on the list.

Note: Data in all charts from records taken at Sea-Tac Airport.