USDA Hardiness Zone 7b
Frost Dates for 73109 — Oklahoma City, Oklahoma
NOAA 1991–2020 normals from Oklahoma City Will Rogers Airport, OK (1,285 ft), 5 miles southwest.
Updated
In Oklahoma City, the last spring frost (32°F) is around April 4 in half of years and has passed by April 20 in nine years out of ten. The first fall frost comes around November 2, as early as October 21 one year in ten, leaving a typical freeze-free season of 213 days (NOAA, Oklahoma City Will Rogers Airport, OK).
- Last spring frost
- April 4
- First fall frost
- November 2
- Growing season
- 213 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 Oklahoma City
Half of springs at Oklahoma City Will Rogers Airport, OK see their last 32°F night by April 4; only one in ten is past it by March 16, and one in ten still has one after April 20. Planting tender crops after April 10 leaves a 30% risk of a frost on them, after April 15 20%, and after April 20 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 2 in half of years, as early as October 21 one year in ten, and holds off past November 17 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 7, 13 days before the 32°F one. The freeze-free season lasts 213 days in a typical year, longer than at 59% of the 114 Oklahoma stations; it reaches 235 days one year in ten and falls short of 191 one year in ten. On average 72 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 11 days longer, to about April 15, and return around October 26. Severe cold of 16°F or below comes in 99% of winters, usually between December 18 and February 14.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 31 | Apr 5 | Apr 9 | Apr 12 | Apr 15 | Apr 18 | Apr 21 | Apr 24 | Apr 30 |
| 32°F | Mar 16 | Mar 22 | Mar 28 | Mar 31 | Apr 4 | Apr 7 | Apr 10 | Apr 15 | Apr 20 |
| 28°F | Mar 3 | Mar 9 | Mar 13 | Mar 17 | Mar 21 | Mar 26 | Mar 30 | Apr 3 | Apr 7 |
| 24°F | Feb 20 | Feb 25 | Mar 1 | Mar 4 | Mar 8 | Mar 12 | Mar 16 | Mar 21 | Mar 29 |
| 20°F | Feb 4 | Feb 13 | Feb 19 | Feb 23 | Feb 28 | Mar 2 | Mar 6 | Mar 10 | Mar 16 |
| 16°F99% of yrs | Jan 16 | Jan 27 | Feb 2 | Feb 8 | Feb 14 | Feb 19 | Feb 25 | Mar 1 | Mar 7 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 12 | Oct 17 | Oct 21 | Oct 23 | Oct 26 | Oct 28 | Oct 31 | Nov 3 | Nov 7 |
| 32°F | Oct 21 | Oct 26 | Oct 29 | Nov 1 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 17 |
| 28°F | Oct 29 | Nov 1 | Nov 4 | Nov 8 | Nov 11 | Nov 15 | Nov 18 | Nov 22 | Nov 27 |
| 24°F | Nov 4 | Nov 9 | Nov 13 | Nov 17 | Nov 21 | Nov 25 | Nov 28 | Dec 2 | Dec 10 |
| 20°F | Nov 13 | Nov 20 | Nov 26 | Nov 29 | Dec 3 | Dec 6 | Dec 12 | Dec 18 | Dec 26 |
| 16°F99% of yrs | Nov 24 | Dec 1 | Dec 6 | Dec 12 | Dec 18 | Dec 23 | Dec 28 | Jan 4 | Jan 14 |
Freeze probabilities 1991–2020 at Oklahoma City Will Rogers Airport, 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 73109 →Compare Oklahoma City with another place →
Weather by month in Oklahoma City
July is the warmest month at Oklahoma City Will Rogers Airport, OK, averaging 93°F by day and 70°F at night; January is the coldest at 49°F and 27°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 59% of years.
Warmth for growing adds up to 4,971 growing degree days a year (base 50°F), fewer than at 75% of the 114 Oklahoma stations. 38% of them (1,871) have built up by the end of June, and July adds the most, 983. Precipitation totals 36.4 inches a year, most in May (5.3") and least in January (1.3"); May to September bring 57% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 49 | 27 | 1.3 | 100% | 22 | 14 |
| Feb | 54 | 31 | 1.4 | 100% | 15 | 39 |
| Mar | 63 | 40 | 2.6 | 98% | 6 | 146 |
| Apr | 71 | 48 | 3.6 | 59% | 1 | 300 |
| May | 79 | 58 | 5.3 | 1% | 0 | 566 |
| Jun | 88 | 66 | 4.5 | 0% | 0 | 805 |
| Jul | 93 | 70 | 3.6 | 0% | 0 | 983 |
| Aug | 92 | 69 | 3.6 | 0% | 0 | 950 |
| Sep | 84 | 62 | 3.7 | 0% | 0 | 681 |
| Oct | 73 | 49 | 3.3 | 39% | 1 | 361 |
| Nov | 61 | 38 | 1.7 | 99% | 8 | 106 |
| Dec | 50 | 30 | 1.8 | 100% | 19 | 20 |
Monthly normals 1991–2020 at Oklahoma City Will Rogers Airport, OK (1,285 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 Post Airport, OK, 10 miles northwest of Oklahoma City, has a last frost 2 days earlier (April 2), a first frost 2 days later (November 4), a season 3 days longer.
When it snows in Oklahoma City, Oklahoma
The first measurable snow (0.1 inch or more) in Oklahoma 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, 5.3 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 46 days after the last snow.
Planting calendar for 73109
| 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 73109 is 5 miles from Oklahoma City Will Rogers Airport, OK, which stands at 1,285 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 73160 (Moore). The 2023 USDA Plant Hardiness Zone Map lists ZIP 73109 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.