USDA Hardiness Zone 6b
Frost Dates for 66207 — Overland Park, Kansas
NOAA 1991–2020 normals from Olathe 3E, KS (1,055 ft), 8 miles southwest.
Updated
In Overland Park, the last spring frost (32°F) is around April 10 in half of years and has passed by April 24 in nine years out of ten. The first fall frost comes around October 29, as early as October 13 one year in ten, leaving a typical freeze-free season of 202 days (NOAA, Olathe 3E, KS).
- Last spring frost
- April 10
- First fall frost
- October 29
- Growing season
- 202 days
- Hardiness zone
- 6b
50% probability
50% probability
freeze-free, 50%
-5 to 0°F (-20.6 to -17.8°C) coldest night
- First snow
- November 30
- Last snow
- March 13
- Winters with snow
- 100%
- Snow per year
- 13.8"
median, 1991–2020
median, 1991–2020
19 of 19 observed
NOAA normal
Frost risk by date in Overland Park
Half of springs at Olathe 3E, KS see their last 32°F night by April 10; only one in ten is past it by March 27, and one in ten still has one after April 24. Planting tender crops after April 16 leaves a 30% risk of a frost on them, after April 20 20%, and after April 24 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 44% of the 110 Kansas stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 29 in half of years, as early as October 13 one year in ten, and holds off past November 12 one year in ten. A hard freeze of 28°F follows 8 days later, around November 6; in spring the one-in-ten date for 28°F is April 17, 7 days before the 32°F one. The freeze-free season lasts 202 days in a typical year, longer than at 88% of the 110 Kansas stations; it reaches 223 days one year in ten and falls short of 181 one year in ten. On average 98 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 9 days longer, to about April 19, and return around October 20. Severe cold of 16°F or below comes every winter, usually between December 5 and March 2.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 5 | Apr 10 | Apr 14 | Apr 17 | Apr 19 | Apr 22 | Apr 26 | Apr 29 | May 2 |
| 32°F | Mar 27 | Apr 1 | Apr 4 | Apr 7 | Apr 10 | Apr 13 | Apr 16 | Apr 20 | Apr 24 |
| 28°F | Mar 13 | Mar 20 | Mar 24 | Mar 29 | Mar 31 | Apr 3 | Apr 7 | Apr 10 | Apr 17 |
| 24°F | Mar 3 | Mar 8 | Mar 12 | Mar 16 | Mar 20 | Mar 24 | Mar 29 | Mar 31 | Apr 6 |
| 20°F | Feb 23 | Feb 28 | Mar 3 | Mar 7 | Mar 10 | Mar 14 | Mar 19 | Mar 23 | Mar 31 |
| 16°F | Feb 13 | Feb 20 | Feb 25 | Feb 28 | Mar 2 | Mar 5 | Mar 9 | Mar 13 | Mar 18 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 2 | Oct 9 | Oct 14 | Oct 17 | Oct 20 | Oct 22 | Oct 25 | Oct 27 | Oct 31 |
| 32°F | Oct 13 | Oct 19 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 12 |
| 28°F | Oct 23 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 13 | Nov 17 | Nov 25 |
| 24°F | Oct 31 | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 19 | Nov 23 | Nov 28 | Dec 3 |
| 20°F | Nov 6 | Nov 12 | Nov 18 | Nov 22 | Nov 26 | Nov 30 | Dec 3 | Dec 7 | Dec 14 |
| 16°F | Nov 17 | Nov 24 | Nov 28 | Dec 2 | Dec 5 | Dec 9 | Dec 13 | Dec 18 | Dec 24 |
Freeze probabilities 1991–2020 at Olathe 3E, KS, 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 66207 →Compare Overland Park with another place →
Weather by month in Overland Park
July is the warmest month at Olathe 3E, KS, averaging 88°F by day and 69°F at night; January is the coldest at 39°F and 20°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 82% of years.
Warmth for growing adds up to 4,094 growing degree days a year (base 50°F), more than at 50% of the 110 Kansas stations. 36% of them (1,470) have built up by the end of June, and July adds the most, 893. Precipitation totals 41.0 inches a year, most in May (5.3") and least in January (1.3"); May to September bring 59% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 39 | 20 | 1.3 | 100% | 27 | 2 |
| Feb | 44 | 24 | 1.7 | 100% | 20 | 10 |
| Mar | 55 | 34 | 2.5 | 99% | 13 | 69 |
| Apr | 65 | 44 | 4.1 | 82% | 3 | 197 |
| May | 75 | 56 | 5.3 | 0% | 0 | 466 |
| Jun | 84 | 65 | 5.2 | 0% | 0 | 727 |
| Jul | 88 | 69 | 4.8 | 0% | 0 | 893 |
| Aug | 87 | 67 | 4.5 | 0% | 0 | 832 |
| Sep | 79 | 58 | 4.3 | 2% | 0 | 563 |
| Oct | 68 | 47 | 3.1 | 59% | 1 | 264 |
| Nov | 54 | 35 | 2.4 | 100% | 12 | 63 |
| Dec | 43 | 25 | 1.8 | 100% | 23 | 8 |
Monthly normals 1991–2020 at Olathe 3E, KS (1,055 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, Olathe Johnson Co Exec Airport, KS, 9 miles southwest of Overland Park, has a last frost 2 days earlier (April 8), the same first-frost date, a season 2 days longer.
When it snows in Overland Park, Kansas
The first measurable snow (0.1 inch or more) in Overland Park usually arrives around November 30, and the last of the season around March 13. Those are the middle dates across the winters of 1991–2020 at Olathe 3E, KS, 7.8 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 28 days after the last snow.
Planting calendar for 66207
| When | What to do |
|---|---|
| January 30 – February 13 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 13 – February 27 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 13 – March 27 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 10 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 6 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 15 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 29 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 66207 is 8 miles from Olathe 3E, KS, which stands at 1,055 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 13 other ZIP codes share the station; its figures are presented in full for 66062 (Olathe). The 2023 USDA Plant Hardiness Zone Map lists ZIP 66207 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°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.