Frost dates in Sinclair, WY

The average last spring frost in Sinclair is around May 31 and the first fall frost is around September 17. That gives Sinclair an average growing season of about 109 days.

Last spring frost

Early (10% chance after)May 13
Average (50%)May 31
Late (90%)June 17

First fall frost

Early (10%)September 3
Average (50%)September 17
Late (90% chance before)September 26

See the Sinclair planting calendar →