Frost dates in Jefferson, WI

The average last spring frost in Jefferson is around April 27 and the first fall frost is around October 17. That gives Jefferson an average growing season of about 173 days.

Last spring frost

Early (10% chance after)April 17
Average (50%)April 27
Late (90%)May 7

First fall frost

Early (10%)October 8
Average (50%)October 17
Late (90% chance before)October 28

See the Jefferson planting calendar →