Last spring frost
Mar 31
Frost Dates for Wynona, OK
First fall frost
Oct 31
Growing season
212 days
Hardiness zone
7a
In an average year around Wynona, OK, the last spring frost (32°F) is about Mar 31 and the first fall frost is about Oct 31, giving roughly a 212-day growing season. To be safe most years, wait until Mar 12 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Apr 27 | Apr 11 | Mar 28 |
| Freeze (32°F) | Apr 14 | Mar 31 | Mar 12 |
| Hard (28°F) | Apr 6 | Mar 20 | Feb 28 |
| Severe (24°F) | Mar 27 | Mar 8 | Feb 20 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 27 | Apr 22 | Apr 17 | Apr 14 | Apr 11 | Apr 8 | Apr 5 | Mar 31 | Mar 28 |
| 32°F | Apr 14 | Apr 9 | Apr 6 | Apr 3 | Mar 31 | Mar 28 | Mar 25 | Mar 20 | Mar 12 |
| 28°F | Apr 6 | Apr 1 | Mar 28 | Mar 24 | Mar 20 | Mar 16 | Mar 11 | Mar 6 | Feb 28 |
| 24°F | Mar 27 | Mar 20 | Mar 16 | Mar 11 | Mar 8 | Mar 4 | Feb 28 | Feb 25 | Feb 20 |
| 20°F | Mar 16 | Mar 9 | Mar 5 | Mar 2 | Feb 28 | Feb 24 | Feb 21 | Feb 15 | Feb 7 |
| 16°F | Mar 7 | Mar 2 | Feb 26 | Feb 22 | Feb 17 | Feb 13 | Feb 7 | Feb 1 | Jan 26 |
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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 4 | Oct 21 | Nov 3 |
| Freeze (32°F) | Oct 14 | Oct 31 | Nov 13 |
| Hard (28°F) | Oct 24 | Nov 8 | Nov 27 |
| Severe (24°F) | Nov 1 | Nov 18 | Dec 6 |
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 18 | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 3 |
| 32°F | Oct 14 | Oct 21 | Oct 25 | Oct 28 | Oct 31 | Nov 1 | Nov 4 | Nov 8 | Nov 13 |
| 28°F | Oct 24 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 21 | Nov 27 |
| 24°F | Nov 1 | Nov 6 | Nov 10 | Nov 14 | Nov 18 | Nov 23 | Nov 27 | Dec 1 | Dec 6 |
| 20°F | Nov 8 | Nov 15 | Nov 22 | Nov 26 | Dec 1 | Dec 5 | Dec 9 | Dec 14 | Dec 21 |
| 16°F | Nov 21 | Nov 30 | Dec 5 | Dec 10 | Dec 14 | Dec 19 | Dec 23 | Dec 29 | Jan 5 |
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
@endif These dates are computed from the nearest official weather station with long-term records: Barnsdall, Ok, about 9.6 miles away@if(!empty($station['elevation_ft'])), at 770 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
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 Wynona, OK?
On average, the last spring frost (32°F) around Wynona, OK is about Mar 31. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 12.
When is the first frost in the fall?
The first fall frost around Wynona, OK typically arrives about Oct 31. 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 Mar 31 on average, or Mar 12 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 212 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 74084 Planting calendar → Oklahoma frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026