USDA Hardiness Zone 7b
Frost Dates for 73080 — Purcell, Oklahoma
NOAA 1991–2020 normals from Purcell 2 SW, OK (1,120 ft), 2 miles south.
Updated
In Purcell, the last spring frost (32°F) is around April 4 in half of years and has passed by April 24 in nine years out of ten. The first fall frost comes around November 2, as early as October 18 one year in ten, leaving a typical freeze-free season of 210 days (NOAA, Purcell 2 SW, OK).
- Last spring frost
- April 4
- First fall frost
- November 2
- Growing season
- 210 days
- Hardiness zone
- 7b
50% probability
50% probability
freeze-free, 50%
5 to 10°F (-15.0 to -12.2°C) coldest night
- First snow
- December 23
- Last snow
- February 13
- Winters with snow
- 96%
- Snow per year
- 4.1"
median, 1991–2020
median, 1991–2020
23 of 24 observed
NOAA normal
Frost risk by date in Purcell
Half of springs at Purcell 2 SW, OK see their last 32°F night by April 4; only one in ten is past it by March 18, and one in ten still has one after April 24. Planting tender crops after April 11 leaves a 30% risk of a frost on them, after April 18 20%, and after April 24 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 92% of the 114 Oklahoma stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 2 in half of years, as early as October 18 one year in ten, and holds off past November 18 one year in ten. A hard freeze of 28°F follows 9 days later, around November 11; in spring the one-in-ten date for 28°F is April 10, 14 days before the 32°F one. The freeze-free season lasts 210 days in a typical year, shorter than at 50% of the 114 Oklahoma stations; it reaches 234 days one year in ten and falls short of 187 one year in ten. On average 80 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 13 days longer, to about April 17, and return around October 24. Severe cold of 16°F or below comes in 99% of winters, usually between December 16 and February 14.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 31 | Apr 5 | Apr 9 | Apr 13 | Apr 17 | Apr 20 | Apr 24 | Apr 28 | May 4 |
| 32°F | Mar 18 | Mar 25 | Mar 29 | Apr 2 | Apr 4 | Apr 7 | Apr 11 | Apr 18 | Apr 24 |
| 28°F | Mar 3 | Mar 11 | Mar 15 | Mar 20 | Mar 23 | Mar 27 | Mar 31 | Apr 4 | Apr 10 |
| 24°F | Feb 21 | Feb 27 | Mar 2 | Mar 6 | Mar 10 | Mar 14 | Mar 17 | Mar 23 | Mar 30 |
| 20°F | Feb 3 | Feb 11 | Feb 19 | Feb 24 | Feb 28 | Mar 3 | Mar 7 | Mar 12 | Mar 17 |
| 16°F99% of yrs | Jan 20 | Jan 29 | Feb 4 | Feb 9 | Feb 14 | Feb 21 | Feb 27 | Mar 3 | Mar 10 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 8 | Oct 14 | Oct 19 | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 2 | Nov 6 |
| 32°F | Oct 18 | Oct 24 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 7 | Nov 11 | Nov 18 |
| 28°F | Oct 25 | Oct 31 | Nov 4 | Nov 7 | Nov 11 | Nov 14 | Nov 17 | Nov 21 | Nov 27 |
| 24°F | Nov 1 | Nov 7 | Nov 13 | Nov 17 | Nov 21 | Nov 25 | Nov 30 | Dec 3 | Dec 8 |
| 20°F | Nov 10 | Nov 19 | Nov 25 | Nov 29 | Dec 2 | Dec 5 | Dec 10 | Dec 15 | Dec 24 |
| 16°F99% of yrs | Nov 23 | Dec 1 | Dec 5 | Dec 11 | Dec 16 | Dec 22 | Dec 27 | Jan 2 | Jan 13 |
Freeze probabilities 1991–2020 at Purcell 2 SW, OK, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 73080 →Compare Purcell with another place →
Weather by month in Purcell
July is the warmest month at Purcell 2 SW, OK, averaging 94°F by day and 70°F at night; January is the coldest at 52°F and 26°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 62% of years.
Warmth for growing adds up to 5,246 growing degree days a year (base 50°F), more than at 66% of the 114 Oklahoma stations. 38% of them (1,987) have built up by the end of June, and July adds the most, 1,002.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 52 | 26 | 100% | 23 | 15 |
| Feb | 58 | 31 | 100% | 15 | 43 |
| Mar | 66 | 40 | 97% | 10 | 177 |
| Apr | 74 | 48 | 62% | 2 | 334 |
| May | 81 | 57 | 4% | 0 | 589 |
| Jun | 89 | 67 | 0% | 0 | 829 |
| Jul | 94 | 70 | 0% | 0 | 1002 |
| Aug | 94 | 68 | 0% | 0 | 968 |
| Sep | 86 | 62 | 0% | 0 | 709 |
| Oct | 76 | 50 | 41% | 1 | 418 |
| Nov | 63 | 38 | 98% | 10 | 130 |
| Dec | 54 | 30 | 100% | 19 | 31 |
Monthly normals 1991–2020 at Purcell 2 SW, OK (1,120 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Norman 3SSE, OK, 12 miles north of Purcell, has a last frost 1 day earlier (April 3), a first frost 1 day later (November 3), a season 2 days longer.
When it snows in Purcell, Oklahoma
The first measurable snow (0.1 inch or more) in Purcell usually arrives around December 23, and the last of the season around February 13. Those are the middle dates across the winters of 1991–2020 at Norman 3SSE, OK, 11.5 miles away: half of years saw snow earlier, half later. Snow fell in 96% of those winters. The last 32°F night of spring typically comes 50 days after the last snow.
Planting calendar for 73080
| When | What to do |
|---|---|
| January 24 – February 7 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 7 – February 21 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 7 – March 21 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 4 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 10 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 19 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 2 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 73080 is 2 miles from Purcell 2 SW, OK, which stands at 1,120 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 73080 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.