Plant By Frost

Minnesota

Frost dates for Willmar Wwtp, MN

At this NOAA station the last spring frost (32°F) usually comes by April 30 and the first fall frost around October 7, giving a growing season of about 159 days.

April 30average last spring frost
October 7average first fall frost
JanAprJulOctDec

Frost odds

1 year in 10 the last spring frost is later thanMay 13
Half of years the last spring frost is later thanApril 30
9 years in 10 the last spring frost is later thanApril 16
1 year in 10 the first fall frost is earlier thanSeptember 23
Half of years the first fall frost is earlier thanOctober 7
9 years in 10 the first fall frost is earlier thanOctober 21

A hard freeze (28°F) usually ends by April 19 and returns around October 19.

A light frost (36°F, which can still nip tender plants) usually ends by May 9 and returns around September 29.

Station USC00219004, elevation 335 m. Based on 19 years of 1991 to 2020 records. A garden higher up, in a hollow or far from this station can freeze later in spring.

Check another ZIP

Sources

  1. U.S. Annual/Seasonal Climate Normals, 1991 to 2020 (freeze probability dates by station), NOAA National Centers for Environmental Information, checked 1 November 2026
  2. Annual/Seasonal Normals 1991 to 2020 documentation, NOAA National Centers for Environmental Information, checked 1 November 2026
  3. 2024 Gazetteer Files, ZIP Code Tabulation Areas, US Census Bureau, checked 1 November 2026