Harman US

Frost Dates for Alva, OK

Last spring frost
Apr 10
First fall frost
Oct 28
Growing season
199 days
Hardiness zone
7a

In an average year around Alva, OK, the last spring frost (32°F) is about Apr 10 and the first fall frost is about Oct 28, giving roughly a 199-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 - Alva, OK
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 2 Apr 20 Apr 7
Freeze (32°F) Apr 25 Apr 10 Mar 26
Hard (28°F) Apr 14 Mar 31 Mar 12
Severe (24°F) Apr 5 Mar 18 Feb 28
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 2 Apr 29 Apr 26 Apr 23 Apr 20 Apr 17 Apr 14 Apr 11 Apr 7
32°F Apr 25 Apr 20 Apr 16 Apr 13 Apr 10 Apr 7 Apr 4 Apr 1 Mar 26
28°F Apr 14 Apr 10 Apr 6 Apr 3 Mar 31 Mar 28 Mar 24 Mar 19 Mar 12
24°F Apr 5 Mar 31 Mar 27 Mar 22 Mar 18 Mar 13 Mar 9 Mar 5 Feb 28
20°F Mar 27 Mar 18 Mar 13 Mar 10 Mar 6 Mar 2 Feb 27 Feb 23 Feb 15
16°F Mar 14 Mar 7 Mar 3 Feb 28 Feb 24 Feb 19 Feb 14 Feb 8 Jan 30

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 - Alva, OK
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 4 Oct 18 Oct 31
Freeze (32°F) Oct 14 Oct 28 Nov 10
Hard (28°F) Oct 22 Nov 5 Nov 20
Severe (24°F) Oct 29 Nov 13 Dec 1
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 4 Oct 10 Oct 14 Oct 16 Oct 18 Oct 21 Oct 23 Oct 27 Oct 31
32°F Oct 14 Oct 18 Oct 21 Oct 24 Oct 28 Oct 30 Nov 2 Nov 5 Nov 10
28°F Oct 22 Oct 27 Oct 30 Nov 2 Nov 5 Nov 7 Nov 10 Nov 15 Nov 20
24°F Oct 29 Nov 2 Nov 6 Nov 10 Nov 13 Nov 18 Nov 21 Nov 25 Dec 1
20°F Nov 3 Nov 10 Nov 15 Nov 19 Nov 23 Nov 27 Nov 30 Dec 4 Dec 11
16°F Nov 13 Nov 20 Nov 26 Nov 30 Dec 3 Dec 7 Dec 12 Dec 18 Dec 26

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 1W, Ok, about 5.9 miles away@if(!empty($station['elevation_ft'])), at 1,464 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 Alva, OK?

On average, the last spring frost (32°F) around Alva, OK is about Apr 10. 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 Alva, OK typically arrives about Oct 28. 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 10 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 199 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 73717 Planting calendar → Oklahoma frost dates →

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