Frost dates for 74431Dewar, OK
The average last spring frost in Dewar is April 8 and the average first fall frost is October 28, giving a typical growing season of about 203 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 8
- Average first fall frost
- Oct 28
- Growing season
- 203 days
Safer after Apr 25 (1-in-10 risk)
Possible by Oct 12 (1-in-10 risk)
First frost typically in 3 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Mar 31 · Apr 19 · May 3 | Oct 5 · Oct 20 · Nov 2 | 184 days | 100% |
| Frost / freeze (32°F) | Mar 23 · Apr 8 · Apr 25 | Oct 12 · Oct 28 · Nov 11 | 203 days | 100% |
| Hard freeze (28°F) | Mar 11 · Mar 29 · Apr 15 | Oct 22 · Nov 6 · Nov 23 | 224 days | 100% |
Planting calendar for Dewar
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 8 – May 14 |
| Tomatoes | Transplant outdoors | Apr 24 – Jul 8 |
| Peppers | Start seeds indoors | Mar 8 – Apr 8 |
| Peppers | Transplant outdoors | May 8 – Jun 8 |
| Eggplant | Start seeds indoors | Mar 25 – Apr 23 |
| Eggplant | Transplant outdoors | May 8 – Jun 8 |
| Cucumbers | Sow outdoors | May 8 – Jul 18 |
| Summer squash | Sow outdoors | Apr 24 – Jun 8 |
| Winter squash & pumpkins | Sow outdoors | May 8 – Jun 8 |
| Snap beans | Sow outdoors | Apr 24 – Aug 10 |
| Sweet corn | Sow outdoors | Apr 24 – Jul 8 |
| Watermelon & cantaloupe | Sow outdoors | May 8 – Jun 8 |
| Okra | Sow outdoors | May 1 – May 24 |
| Peas | Sow outdoors (spring) | Mar 8 – Apr 23 |
| Potatoes | Plant outdoors (spring) | Mar 8 – May 8 |
| Onions | Start seeds indoors (spring) | Jan 25 – Feb 21 |
| Onions | Transplant outdoors (spring) | Mar 25 – Apr 23 |
| Broccoli | Start seeds indoors (spring) | Feb 18 – Mar 24 |
| Broccoli | Transplant outdoors (spring) | Mar 25 – Apr 23 |
| Broccoli | Start seeds indoors (fall) | Jun 28 – Jul 8 |
| Broccoli | Transplant outdoors (fall) | Jul 28 – Aug 8 |
| Cabbage | Start seeds indoors (spring) | Feb 8 – Mar 8 |
| Cabbage | Transplant outdoors (spring) | Mar 8 – Apr 8 |
| Cabbage | Start seeds indoors (fall) | Jun 18 – Jul 18 |
| Cabbage | Transplant outdoors (fall) | Jul 18 – Aug 18 |
| Leaf lettuce | Sow outdoors (spring) | Mar 8 – May 24 |
| Leaf lettuce | Sow outdoors (fall) | Jul 18 – Sep 3 |
| Spinach | Sow outdoors (spring) | Mar 1 – Apr 14 |
| Spinach | Sow outdoors (fall) | Aug 4 – Sep 8 |
| Radishes | Sow outdoors (spring) | Mar 8 – Apr 28 |
| Radishes | Sow outdoors (fall) | Jul 18 – Sep 18 |
| Kale | Sow outdoors (spring) | Mar 25 – Apr 14 |
| Kale | Sow outdoors (fall) | Jul 11 – Aug 18 |
| Carrots | Sow outdoors (spring) | Apr 8 – May 24 |
| Carrots | Sow outdoors (fall) | Jun 18 – Aug 3 |
| Garlic | Plant outdoors (fall) | Oct 18 – Nov 18 |
Where these dates come from
ZIP code 74431 is matched to the NOAA station Okmulgee Wtr Wks, OK, 20 km away, at 647 ft elevation (6 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Okmulgee Wtr Wks, OK (used) | 647 ft | Apr 8 | Oct 28 |
| Okemah, OK | 935 ft | Mar 24 | Nov 9 |
| Holdenville 3Ese Mesonet, OK | 918 ft | Mar 29 | Nov 5 |
| Bristow, OK | 830 ft | Apr 9 | Oct 25 |
Frost dates near Dewar
- Henryetta, OK 74437 · last Mar 24, first Nov 9
- Schulter, OK 74460 · last Apr 8, first Oct 28
- Hitchita, OK 74438 · last Apr 2, first Nov 2
- Okmulgee, OK 74447 · last Apr 8, first Oct 28
- Weleetka, OK 74880 · last Mar 24, first Nov 9
- Hanna, OK 74845 · last Mar 31, first Nov 3
- Stidham, OK 74461 · last Apr 2, first Nov 2
- Dustin, OK 74839 · last Mar 24, first Nov 9
Frequently asked questions
- When is the last frost in Dewar, OK?
- For ZIP code 74431, the average last spring frost (32°F) is April 8, based on NOAA 1991-2020 climate normals for the Okmulgee Wtr Wks, OK weather station. There is a 1-in-10 chance of a frost after April 25.
- When is the first frost in Dewar, OK?
- The average first fall frost (32°F) is October 28. There is a 1-in-10 chance of frost by October 12, so tender plants are at risk from that point on.
- How long is the growing season in 74431?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 203 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.