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Frost Dates for Athens, WI

Last spring frost
May 11
First fall frost
Oct 1
Growing season
141 days
Hardiness zone
4b

In an average year around Athens, WI, the last spring frost (32°F) is about May 11 and the first fall frost is about Oct 1, giving roughly a 141-day growing season. To be safe most years, wait until Apr 29 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 - Athens, WI
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Jun 6 May 23 May 8
Freeze (32°F) May 26 May 11 Apr 29
Hard (28°F) May 15 May 1 Apr 18
Severe (24°F) May 3 Apr 20 Apr 5
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Jun 6 Jun 1 May 29 May 26 May 23 May 20 May 17 May 13 May 8
32°F May 26 May 21 May 18 May 14 May 11 May 8 May 5 May 3 Apr 29
28°F May 15 May 10 May 6 May 3 May 1 Apr 29 Apr 26 Apr 23 Apr 18
24°F May 3 Apr 29 Apr 26 Apr 23 Apr 20 Apr 17 Apr 14 Apr 10 Apr 5
20°F Apr 25 Apr 20 Apr 16 Apr 13 Apr 9 Apr 7 Apr 4 Apr 1 Mar 28
16°F Apr 17 Apr 11 Apr 7 Apr 5 Apr 2 Mar 31 Mar 29 Mar 25 Mar 19

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 - Athens, WI
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 7 Sep 22 Oct 4
Freeze (32°F) Sep 17 Oct 1 Oct 13
Hard (28°F) Sep 27 Oct 11 Oct 25
Severe (24°F) Oct 8 Oct 23 Nov 6
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 7 Sep 13 Sep 16 Sep 19 Sep 22 Sep 25 Sep 28 Oct 1 Oct 4
32°F Sep 17 Sep 22 Sep 26 Sep 28 Oct 1 Oct 4 Oct 6 Oct 9 Oct 13
28°F Sep 27 Oct 1 Oct 5 Oct 8 Oct 11 Oct 14 Oct 17 Oct 20 Oct 25
24°F Oct 8 Oct 13 Oct 16 Oct 20 Oct 23 Oct 26 Oct 30 Nov 1 Nov 6
20°F Oct 19 Oct 25 Oct 29 Nov 1 Nov 3 Nov 5 Nov 9 Nov 12 Nov 16
16°F Nov 1 Nov 3 Nov 6 Nov 9 Nov 13 Nov 15 Nov 17 Nov 21 Nov 25

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: Medford, Wi, about 15.9 miles away@if(!empty($station['elevation_ft'])), at 1,470 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 Athens, WI?

On average, the last spring frost (32°F) around Athens, WI is about May 11. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 29.

When is the first frost in the fall?

The first fall frost around Athens, WI typically arrives about Oct 1. 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 May 11 on average, or Apr 29 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 141 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 54411 Planting calendar → Wisconsin frost dates →

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