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Frost Dates for Milwaukee, WI

Last spring frost
Apr 26
First fall frost
Oct 22
Growing season
177 days
Hardiness zone
6a

In an average year around Milwaukee, WI, the last spring frost (32°F) is about Apr 26 and the first fall frost is about Oct 22, giving roughly a 177-day growing season. To be safe most years, wait until Apr 12 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 23 May 8 Apr 23
Freeze (32°F) May 12 Apr 26 Apr 12
Hard (28°F) Apr 30 Apr 14 Apr 1
Severe (24°F) Apr 15 Apr 2 Mar 18
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 23 May 18 May 14 May 11 May 8 May 4 May 1 Apr 27 Apr 23
32°F May 12 May 6 May 2 Apr 29 Apr 26 Apr 23 Apr 20 Apr 16 Apr 12
28°F Apr 30 Apr 24 Apr 20 Apr 16 Apr 14 Apr 10 Apr 7 Apr 4 Apr 1
24°F Apr 15 Apr 11 Apr 7 Apr 4 Apr 2 Mar 31 Mar 28 Mar 23 Mar 18
20°F Apr 5 Apr 2 Mar 30 Mar 27 Mar 23 Mar 20 Mar 16 Mar 13 Mar 7
16°F Mar 28 Mar 23 Mar 19 Mar 16 Mar 13 Mar 10 Mar 7 Mar 4 Feb 28

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) Sep 29 Oct 10 Oct 24
Freeze (32°F) Oct 7 Oct 22 Nov 3
Hard (28°F) Oct 19 Nov 1 Nov 14
Severe (24°F) Nov 1 Nov 11 Nov 25
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 29 Oct 2 Oct 5 Oct 8 Oct 10 Oct 13 Oct 16 Oct 19 Oct 24
32°F Oct 7 Oct 12 Oct 16 Oct 19 Oct 22 Oct 25 Oct 28 Oct 31 Nov 3
28°F Oct 19 Oct 24 Oct 28 Oct 31 Nov 1 Nov 4 Nov 7 Nov 10 Nov 14
24°F Nov 1 Nov 3 Nov 6 Nov 9 Nov 11 Nov 14 Nov 17 Nov 20 Nov 25
20°F Nov 7 Nov 12 Nov 15 Nov 18 Nov 20 Nov 23 Nov 26 Nov 30 Dec 5
16°F Nov 13 Nov 18 Nov 22 Nov 26 Nov 29 Dec 1 Dec 4 Dec 9 Dec 15

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: West Allis, Wi, about 3.7 miles away@if(!empty($station['elevation_ft'])), at 723 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 26. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 12.

When is the first frost in the fall?

The first fall frost around Milwaukee, WI typically arrives about Oct 22. 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 26 on average, or Apr 12 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 177 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 53233 Planting calendar → Wisconsin frost dates →

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