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Frost Dates for Milwaukee, WI

Last spring frost
Apr 19
First fall frost
Oct 29
Growing season
192 days
Hardiness zone
6a

In an average year around Milwaukee, WI, the last spring frost (32°F) is about Apr 19 and the first fall frost is about Oct 29, giving roughly a 192-day growing season. To be safe most years, wait until Apr 6 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Milwaukee, WI
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 15 May 1 Apr 18
Freeze (32°F) May 2 Apr 19 Apr 6
Hard (28°F) Apr 20 Apr 6 Mar 24
Severe (24°F) Apr 9 Mar 28 Mar 11
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 15 May 10 May 7 May 4 May 1 Apr 30 Apr 27 Apr 23 Apr 18
32°F May 2 Apr 29 Apr 25 Apr 22 Apr 19 Apr 16 Apr 13 Apr 9 Apr 6
28°F Apr 20 Apr 15 Apr 11 Apr 9 Apr 6 Apr 4 Apr 2 Mar 30 Mar 24
24°F Apr 9 Apr 5 Apr 2 Mar 31 Mar 28 Mar 25 Mar 21 Mar 17 Mar 11
20°F Mar 30 Mar 27 Mar 23 Mar 19 Mar 16 Mar 14 Mar 10 Mar 7 Mar 2
16°F Mar 23 Mar 18 Mar 14 Mar 11 Mar 8 Mar 5 Mar 3 Feb 27 Feb 22

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Milwaukee, WI
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 5 Oct 18 Oct 30
Freeze (32°F) Oct 15 Oct 29 Nov 10
Hard (28°F) Oct 27 Nov 8 Nov 22
Severe (24°F) Nov 3 Nov 17 Dec 1
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 5 Oct 9 Oct 13 Oct 15 Oct 18 Oct 21 Oct 24 Oct 26 Oct 30
32°F Oct 15 Oct 20 Oct 24 Oct 26 Oct 29 Nov 1 Nov 2 Nov 6 Nov 10
28°F Oct 27 Nov 1 Nov 3 Nov 5 Nov 8 Nov 10 Nov 13 Nov 17 Nov 22
24°F Nov 3 Nov 7 Nov 10 Nov 13 Nov 17 Nov 20 Nov 24 Nov 27 Dec 1
20°F Nov 9 Nov 15 Nov 19 Nov 24 Nov 27 Nov 29 Dec 2 Dec 6 Dec 13
16°F Nov 18 Nov 25 Nov 29 Dec 1 Dec 4 Dec 8 Dec 12 Dec 17 Dec 22

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Milwaukee Mitchell Ap, Wi, about 2 miles away@if(!empty($station['elevation_ft'])), at 670 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

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How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Milwaukee, WI?

On average, the last spring frost (32°F) around Milwaukee, WI is about Apr 19. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 6.

When is the first frost in the fall?

The first fall frost around Milwaukee, WI typically arrives about Oct 29. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 19 on average, or Apr 6 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 192 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 53221 Planting calendar → Wisconsin frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026