Last spring frost
Apr 2
Frost Dates for Blair, OK
First fall frost
Nov 3
Growing season
213 days
Hardiness zone
7b
In an average year around Blair, OK, the last spring frost (32°F) is about Apr 2 and the first fall frost is about Nov 3, giving roughly a 213-day growing season. To be safe most years, wait until Mar 11 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 30 | Apr 14 | Mar 28 |
| Freeze (32°F) | Apr 21 | Apr 2 | Mar 11 |
| Hard (28°F) | Apr 8 | Mar 21 | Feb 28 |
| Severe (24°F) | Mar 30 | Mar 6 | Feb 16 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 30 | Apr 24 | Apr 21 | Apr 17 | Apr 14 | Apr 10 | Apr 7 | Apr 3 | Mar 28 |
| 32°F | Apr 21 | Apr 15 | Apr 10 | Apr 6 | Apr 2 | Mar 30 | Mar 25 | Mar 19 | Mar 11 |
| 28°F | Apr 8 | Apr 3 | Mar 30 | Mar 26 | Mar 21 | Mar 16 | Mar 11 | Mar 5 | Feb 28 |
| 24°F | Mar 30 | Mar 22 | Mar 16 | Mar 10 | Mar 6 | Mar 3 | Feb 28 | Feb 23 | Feb 16 |
| 20°F | Mar 15 | Mar 8 | Mar 3 | Feb 28 | Feb 25 | Feb 20 | Feb 15 | Feb 9 | Jan 31 |
| 16°F | Mar 6 | Mar 1 | Feb 24 | Feb 16 | Feb 10 | Feb 5 | Jan 30 | Jan 23 | Jan 12 |
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 10 | Oct 26 | Nov 7 |
| Freeze (32°F) | Oct 18 | Nov 3 | Nov 18 |
| Hard (28°F) | Oct 25 | Nov 12 | Nov 29 |
| Severe (24°F) | Nov 2 | Nov 22 | Dec 9 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 10 | Oct 17 | Oct 20 | Oct 24 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 7 |
| 32°F | Oct 18 | Oct 24 | Oct 29 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 13 | Nov 18 |
| 28°F | Oct 25 | Nov 1 | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 19 | Nov 24 | Nov 29 |
| 24°F | Nov 2 | Nov 8 | Nov 13 | Nov 18 | Nov 22 | Nov 26 | Nov 29 | Dec 2 | Dec 9 |
| 20°F | Nov 11 | Nov 20 | Nov 25 | Nov 28 | Dec 2 | Dec 5 | Dec 10 | Dec 15 | Dec 23 |
| 16°F | Nov 24 | Dec 1 | Dec 5 | Dec 11 | Dec 17 | Dec 23 | Dec 30 | Jan 4 | Jan 15 |
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: Altus Dam, Ok, about 6.6 miles away@if(!empty($station['elevation_ft'])), at 1,525 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 Blair, OK?
On average, the last spring frost (32°F) around Blair, OK is about Apr 2. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 11.
When is the first frost in the fall?
The first fall frost around Blair, OK typically arrives about Nov 3. 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 2 on average, or Mar 11 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 213 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 73526 Planting calendar → Oklahoma frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026