Frost dates in Prosser, WA

The average last spring frost in Prosser is around May 1 and the first fall frost is around October 13. That gives Prosser an average growing season of about 165 days.

Last spring frost

Early (10% chance after)March 30
Average (50%)May 1
Late (90%)May 23

First fall frost

Early (10%)September 23
Average (50%)October 13
Late (90% chance before)November 2

See the Prosser planting calendar →