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Frost Dates for Minot AFB, ND

Last spring frost
May 10
First fall frost
Oct 1
Growing season
144 days
Hardiness zone
4a

In an average year around Minot AFB, ND, the last spring frost (32°F) is about May 10 and the first fall frost is about Oct 1, giving roughly a 144-day growing season. To be safe most years, wait until Apr 27 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 - Minot AFB, ND
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 31 May 19 May 6
Freeze (32°F) May 22 May 10 Apr 27
Hard (28°F) May 14 Apr 30 Apr 15
Severe (24°F) May 5 Apr 19 Apr 5
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 31 May 27 May 24 May 22 May 19 May 16 May 14 May 11 May 6
32°F May 22 May 18 May 15 May 13 May 10 May 7 May 4 May 1 Apr 27
28°F May 14 May 9 May 6 May 3 Apr 30 Apr 28 Apr 24 Apr 19 Apr 15
24°F May 5 Apr 30 Apr 25 Apr 22 Apr 19 Apr 16 Apr 13 Apr 9 Apr 5
20°F Apr 25 Apr 20 Apr 16 Apr 13 Apr 10 Apr 7 Apr 5 Apr 2 Mar 29
16°F Apr 17 Apr 12 Apr 9 Apr 6 Apr 4 Apr 1 Mar 30 Mar 26 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 - Minot AFB, ND
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 11 Sep 22 Oct 4
Freeze (32°F) Sep 19 Oct 1 Oct 14
Hard (28°F) Sep 27 Oct 10 Oct 23
Severe (24°F) Oct 6 Oct 20 Nov 1
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 11 Sep 15 Sep 18 Sep 20 Sep 22 Sep 25 Sep 27 Sep 30 Oct 4
32°F Sep 19 Sep 23 Sep 27 Sep 29 Oct 1 Oct 3 Oct 6 Oct 9 Oct 14
28°F Sep 27 Oct 1 Oct 4 Oct 7 Oct 10 Oct 13 Oct 15 Oct 19 Oct 23
24°F Oct 6 Oct 10 Oct 14 Oct 17 Oct 20 Oct 23 Oct 25 Oct 28 Nov 1
20°F Oct 13 Oct 18 Oct 22 Oct 25 Oct 28 Oct 31 Nov 2 Nov 5 Nov 11
16°F Oct 22 Oct 27 Oct 30 Nov 1 Nov 4 Nov 7 Nov 10 Nov 14 Nov 20

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: Minot Intl Ap, Nd, about 11.2 miles away@if(!empty($station['elevation_ft'])), at 1,665 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
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 Minot AFB, ND?

On average, the last spring frost (32°F) around Minot AFB, ND is about May 10. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 27.

When is the first frost in the fall?

The first fall frost around Minot AFB, ND 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 10 on average, or Apr 27 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 144 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 58704 Planting calendar → North Dakota frost dates →

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