seattle average rainfall
Rain Stats. Filed in Posted on January 25, 2013 12:52 pm by Justin Shaw. 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.elow are two graphs that, together, show Seattleâs yearly precipitation from 1948 to present. The third chart lists Seattleâ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 1950âthe wettest year on record for the city.