USDA Hardiness Zone 7b
Frost Dates for 73115 — Del City, Oklahoma
NOAA 1991–2020 normals from Spencer 2ENE Mesonet, OK (1,223 ft), 9 miles northeast.
Updated
In Del City, the last spring frost (32°F) is around April 2 in half of years and has passed by April 18 in nine years out of ten. The first fall frost comes around November 5, as early as October 20 one year in ten, leaving a typical freeze-free season of 217 days (NOAA, Spencer 2ENE Mesonet, OK).
- Last spring frost
- April 2
- First fall frost
- November 5
- Growing season
- 217 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 19
- Last snow
- February 17
- Winters with snow
- 100%
- Snow per year
- 6.7"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Del City
Half of springs at Spencer 2ENE Mesonet, OK see their last 32°F night by April 2; only one in ten is past it by March 12, and one in ten still has one after April 18. Planting tender crops after April 8 leaves a 30% risk of a frost on them, after April 13 20%, and after April 18 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 61% of the 114 Oklahoma stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 5 in half of years, as early as October 20 one year in ten, and holds off past November 20 one year in ten. A hard freeze of 28°F follows 8 days later, around November 13; in spring the one-in-ten date for 28°F is April 6, 12 days before the 32°F one. The freeze-free season lasts 217 days in a typical year, longer than at 70% of the 114 Oklahoma stations; it reaches 243 days one year in ten and falls short of 194 one year in ten. On average 68 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 10 days longer, to about April 12, and return around October 28. Severe cold of 16°F or below comes in 96% of winters, usually between December 24 and February 9.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 26 | Apr 1 | Apr 5 | Apr 9 | Apr 12 | Apr 16 | Apr 20 | Apr 24 | Apr 28 |
| 32°F | Mar 12 | Mar 20 | Mar 25 | Mar 30 | Apr 2 | Apr 5 | Apr 8 | Apr 13 | Apr 18 |
| 28°F | Feb 28 | Mar 5 | Mar 10 | Mar 13 | Mar 17 | Mar 22 | Mar 27 | Apr 1 | Apr 6 |
| 24°F | Feb 16 | Feb 23 | Feb 27 | Mar 1 | Mar 4 | Mar 8 | Mar 12 | Mar 16 | Mar 25 |
| 20°F | Jan 28 | Feb 6 | Feb 14 | Feb 19 | Feb 24 | Feb 28 | Mar 3 | Mar 7 | Mar 12 |
| 16°F96% of yrs | Jan 6 | Jan 21 | Jan 29 | Feb 3 | Feb 9 | Feb 15 | Feb 20 | Feb 26 | Mar 4 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 14 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Oct 30 | Nov 2 | Nov 5 | Nov 10 |
| 32°F | Oct 20 | Oct 26 | Oct 30 | Nov 2 | Nov 5 | Nov 7 | Nov 10 | Nov 14 | Nov 20 |
| 28°F | Oct 30 | Nov 3 | Nov 6 | Nov 9 | Nov 13 | Nov 17 | Nov 21 | Nov 26 | Dec 1 |
| 24°F | Nov 5 | Nov 11 | Nov 16 | Nov 20 | Nov 25 | Nov 30 | Dec 2 | Dec 6 | Dec 13 |
| 20°F | Nov 15 | Nov 23 | Nov 28 | Dec 2 | Dec 6 | Dec 11 | Dec 17 | Dec 23 | Jan 1 |
| 16°F96% of yrs | Nov 30 | Dec 6 | Dec 12 | Dec 18 | Dec 24 | Dec 29 | Jan 4 | Jan 12 | Jan 27 |
Freeze probabilities 1991–2020 at Spencer 2ENE Mesonet, 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 73115 →Compare Del City with another place →
Weather by month in Del City
July is the warmest month at Spencer 2ENE Mesonet, OK, averaging 92°F by day and 72°F at night; January is the coldest at 50°F and 29°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 55% of years.
Warmth for growing adds up to 5,172 growing degree days a year (base 50°F), more than at 57% of the 114 Oklahoma stations. 38% of them (1,975) have built up by the end of June, and July adds the most, 993.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 50 | 29 | 100% | 20 | 23 |
| Feb | 54 | 32 | 100% | 15 | 56 |
| Mar | 63 | 41 | 96% | 6 | 172 |
| Apr | 71 | 49 | 55% | 2 | 326 |
| May | 79 | 59 | 0% | 0 | 581 |
| Jun | 87 | 68 | 0% | 0 | 817 |
| Jul | 92 | 72 | 0% | 0 | 993 |
| Aug | 92 | 70 | 0% | 0 | 957 |
| Sep | 84 | 63 | 0% | 0 | 696 |
| Oct | 73 | 52 | 35% | 1 | 397 |
| Nov | 61 | 40 | 97% | 7 | 126 |
| Dec | 51 | 31 | 100% | 17 | 29 |
Monthly normals 1991–2020 at Spencer 2ENE Mesonet, OK (1,223 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, Oklahoma City Will Rogers Airport, OK, 10 miles west of Del City, has a last frost 2 days later (April 4), a first frost 3 days earlier (November 2), a season 4 days shorter.
When it snows in Del City, Oklahoma
The first measurable snow (0.1 inch or more) in Del City usually arrives around December 19, and the last of the season around February 17. Those are the middle dates across the winters of 1991–2020 at Oklahoma City Will Rogers Airport, OK, 9.6 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 44 days after the last snow.
Planting calendar for 73115
| When | What to do |
|---|---|
| January 22 – February 5 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 5 – February 19 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 5 – March 19 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 2 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 13 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 22 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 5 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 73115 is 9 miles from Spencer 2ENE Mesonet, OK, which stands at 1,223 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 16 other ZIP codes share the station; its figures are presented in full for 73013 (Edmond). The 2023 USDA Plant Hardiness Zone Map lists ZIP 73115 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.