Harman US

Frost Dates for Hopeton, OK

Last spring frost
Apr 11
First fall frost
Oct 26
Growing season
198 days
Hardiness zone
7a

In an average year around Hopeton, OK, the last spring frost (32°F) is about Apr 11 and the first fall frost is about Oct 26, giving roughly a 198-day growing season. To be safe most years, wait until Mar 26 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 - Hopeton, OK
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 4 Apr 22 Apr 7
Freeze (32°F) Apr 26 Apr 11 Mar 26
Hard (28°F) Apr 15 Apr 1 Mar 13
Severe (24°F) Apr 6 Mar 19 Mar 2
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 4 May 1 Apr 28 Apr 24 Apr 22 Apr 19 Apr 16 Apr 12 Apr 7
32°F Apr 26 Apr 22 Apr 18 Apr 14 Apr 11 Apr 8 Apr 5 Apr 2 Mar 26
28°F Apr 15 Apr 10 Apr 7 Apr 4 Apr 1 Mar 28 Mar 24 Mar 20 Mar 13
24°F Apr 6 Apr 1 Mar 28 Mar 23 Mar 19 Mar 15 Mar 12 Mar 7 Mar 2
20°F Mar 25 Mar 18 Mar 14 Mar 10 Mar 7 Mar 4 Mar 1 Feb 25 Feb 18
16°F Mar 13 Mar 7 Mar 4 Mar 1 Feb 27 Feb 23 Feb 18 Feb 11 Feb 2

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 - Hopeton, OK
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 5 Oct 18 Oct 29
Freeze (32°F) Oct 14 Oct 26 Nov 7
Hard (28°F) Oct 20 Nov 3 Nov 16
Severe (24°F) Oct 28 Nov 11 Nov 26
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 5 Oct 10 Oct 14 Oct 16 Oct 18 Oct 20 Oct 22 Oct 25 Oct 29
32°F Oct 14 Oct 18 Oct 21 Oct 24 Oct 26 Oct 28 Oct 31 Nov 3 Nov 7
28°F Oct 20 Oct 25 Oct 29 Nov 1 Nov 3 Nov 5 Nov 9 Nov 12 Nov 16
24°F Oct 28 Nov 1 Nov 5 Nov 8 Nov 11 Nov 14 Nov 17 Nov 20 Nov 26
20°F Nov 3 Nov 8 Nov 13 Nov 16 Nov 19 Nov 24 Nov 28 Dec 2 Dec 9
16°F Nov 12 Nov 19 Nov 24 Nov 28 Dec 1 Dec 5 Dec 11 Dec 18 Dec 28

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: Alva 7Ssw Mesonet, Ok, about 3 miles away@if(!empty($station['elevation_ft'])), at 1,440 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 Hopeton, OK?

On average, the last spring frost (32°F) around Hopeton, OK is about Apr 11. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 26.

When is the first frost in the fall?

The first fall frost around Hopeton, OK typically arrives about Oct 26. 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 11 on average, or Mar 26 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 198 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 73746 Planting calendar → Oklahoma frost dates →

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