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Frost Dates for Madison, WI

Last spring frost
Apr 28
First fall frost
Oct 15
Growing season
169 days
Hardiness zone
5b

In an average year around Madison, WI, the last spring frost (32°F) is about Apr 28 and the first fall frost is about Oct 15, giving roughly a 169-day growing season. To be safe most years, wait until Apr 14 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 - Madison, WI
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 22 May 7 Apr 25
Freeze (32°F) May 11 Apr 28 Apr 14
Hard (28°F) May 1 Apr 17 Apr 4
Severe (24°F) Apr 20 Apr 6 Mar 24
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 22 May 17 May 13 May 10 May 7 May 4 May 1 Apr 29 Apr 25
32°F May 11 May 6 May 3 Apr 30 Apr 28 Apr 25 Apr 22 Apr 19 Apr 14
28°F May 1 Apr 26 Apr 22 Apr 20 Apr 17 Apr 14 Apr 11 Apr 7 Apr 4
24°F Apr 20 Apr 15 Apr 12 Apr 9 Apr 6 Apr 4 Apr 2 Mar 31 Mar 24
20°F Apr 12 Apr 7 Apr 4 Apr 2 Mar 31 Mar 27 Mar 23 Mar 19 Mar 14
16°F Apr 3 Mar 31 Mar 27 Mar 24 Mar 21 Mar 18 Mar 15 Mar 11 Mar 6

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 - Madison, WI
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 20 Oct 4 Oct 17
Freeze (32°F) Sep 29 Oct 15 Oct 29
Hard (28°F) Oct 10 Oct 25 Nov 6
Severe (24°F) Oct 21 Nov 2 Nov 18
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 20 Sep 25 Sep 28 Oct 1 Oct 4 Oct 6 Oct 9 Oct 12 Oct 17
32°F Sep 29 Oct 5 Oct 9 Oct 12 Oct 15 Oct 18 Oct 21 Oct 24 Oct 29
28°F Oct 10 Oct 16 Oct 20 Oct 22 Oct 25 Oct 27 Oct 30 Nov 1 Nov 6
24°F Oct 21 Oct 27 Oct 30 Nov 1 Nov 2 Nov 5 Nov 9 Nov 13 Nov 18
20°F Oct 31 Nov 3 Nov 7 Nov 10 Nov 12 Nov 15 Nov 18 Nov 22 Nov 27
16°F Nov 6 Nov 11 Nov 15 Nov 18 Nov 21 Nov 24 Nov 27 Dec 1 Dec 7

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: Charmany Farm, Wi, about 1.5 miles away@if(!empty($station['elevation_ft'])), at 1,046 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 Madison, WI?

On average, the last spring frost (32°F) around Madison, WI is about Apr 28. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 14.

When is the first frost in the fall?

The first fall frost around Madison, WI typically arrives about Oct 15. 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 28 on average, or Apr 14 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 169 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 53719 Planting calendar → Wisconsin frost dates →

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