USDA Hardiness Zone 6a
Frost Dates for 63501 — Kirksville, Missouri
NOAA 1991–2020 normals from Kirksville, MO (970 ft), 2 miles north.
Updated
In Kirksville, the last spring frost (32°F) is around April 21 in half of years and has passed by May 5 in nine years out of ten. The first fall frost comes around October 19, as early as October 2 one year in ten, leaving a typical freeze-free season of 179 days (NOAA, Kirksville, MO).
- Last spring frost
- April 21
- First fall frost
- October 19
- Growing season
- 179 days
- Hardiness zone
- 6a
50% probability
50% probability
freeze-free, 50%
-10 to -5°F (-23.3 to -20.6°C) coldest night
- First snow
- December 7
- Last snow
- March 11
- Winters with snow
- 100%
- Snow per year
- 19"
median, 1991–2020
median, 1991–2020
26 of 26 observed
NOAA normal
Frost risk by date in Kirksville
Half of springs at Kirksville, MO see their last 32°F night by April 21; only one in ten is past it by April 7, and one in ten still has one after May 5. Planting tender crops after April 28 leaves a 30% risk of a frost on them, after May 1 20%, and after May 5 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 80% of the 158 Missouri stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 19 in half of years, as early as October 2 one year in ten, and holds off past October 31 one year in ten. A hard freeze of 28°F follows 10 days later, around October 29; in spring the one-in-ten date for 28°F is April 27, 8 days before the 32°F one. The freeze-free season lasts 179 days in a typical year, shorter than at 92% of the 158 Missouri stations; it reaches 200 days one year in ten and falls short of 159 one year in ten. On average 126 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 May 2, and return around October 7. Severe cold of 16°F or below comes every winter, usually between November 24 and March 11.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 17 | Apr 23 | Apr 27 | Apr 30 | May 2 | May 4 | May 6 | May 9 | May 13 |
| 32°F | Apr 7 | Apr 12 | Apr 15 | Apr 18 | Apr 21 | Apr 25 | Apr 28 | May 1 | May 5 |
| 28°F | Mar 25 | Mar 31 | Apr 4 | Apr 7 | Apr 10 | Apr 14 | Apr 17 | Apr 21 | Apr 27 |
| 24°F | Mar 12 | Mar 18 | Mar 23 | Mar 28 | Mar 31 | Apr 3 | Apr 5 | Apr 9 | Apr 15 |
| 20°F | Mar 3 | Mar 8 | Mar 12 | Mar 16 | Mar 20 | Mar 24 | Mar 28 | Apr 1 | Apr 7 |
| 16°F | Feb 23 | Mar 1 | Mar 5 | Mar 8 | Mar 11 | Mar 14 | Mar 18 | Mar 22 | Mar 29 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 22 | Sep 28 | Oct 1 | Oct 4 | Oct 7 | Oct 11 | Oct 13 | Oct 17 | Oct 21 |
| 32°F | Oct 2 | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 31 |
| 28°F | Oct 15 | Oct 20 | Oct 24 | Oct 26 | Oct 29 | Oct 31 | Nov 2 | Nov 5 | Nov 10 |
| 24°F | Oct 26 | Oct 31 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 22 |
| 20°F | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 17 | Nov 22 | Nov 27 | Dec 2 |
| 16°F | Nov 7 | Nov 12 | Nov 15 | Nov 20 | Nov 24 | Nov 29 | Dec 2 | Dec 6 | Dec 12 |
Freeze probabilities 1991–2020 at Kirksville, MO, 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 63501 →Compare Kirksville with another place →
Weather by month in Kirksville
July is the warmest month at Kirksville, MO, averaging 86°F by day and 66°F at night; January is the coldest at 34°F and 15°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 22% of years.
Warmth for growing adds up to 3,422 growing degree days a year (base 50°F), fewer than at 97% of the 158 Missouri stations. 35% of them (1,191) have built up by the end of June, and July adds the most, 794. Precipitation totals 42.6 inches a year, most in June (5.9") and least in January (1.4"); May to September bring 59% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 34 | 15 | 1.4 | 100% | 29 | 1 |
| Feb | 38 | 19 | 2.0 | 100% | 24 | 6 |
| Mar | 51 | 29 | 2.7 | 100% | 19 | 40 |
| Apr | 62 | 40 | 4.1 | 96% | 6 | 134 |
| May | 72 | 51 | 5.8 | 22% | <1 | 371 |
| Jun | 81 | 61 | 5.9 | 0% | 0 | 640 |
| Jul | 86 | 66 | 4.9 | 0% | 0 | 794 |
| Aug | 84 | 63 | 4.2 | 0% | 0 | 738 |
| Sep | 77 | 54 | 4.2 | 6% | <1 | 473 |
| Oct | 65 | 43 | 3.3 | 90% | 4 | 188 |
| Nov | 51 | 31 | 2.3 | 100% | 17 | 36 |
| Dec | 39 | 21 | 1.8 | 100% | 27 | 3 |
Monthly normals 1991–2020 at Kirksville, MO (970 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, Kirksville Regional Airport, MO, 6 miles south of Kirksville, has a last frost 2 days earlier (April 19), a first frost 1 day earlier (October 18), a season 1 day longer.
When it snows in Kirksville, Missouri
The first measurable snow (0.1 inch or more) in Kirksville usually arrives around December 7, and the last of the season around March 11. Those are the middle dates across the winters of 1991–2020 at Kirksville, MO, 1.6 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 41 days after the last snow.
Planting calendar for 63501
| When | What to do |
|---|---|
| February 10 – February 24 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 24 – March 10 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 24 – April 7 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 21 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 27 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 5 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 19 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 63501 is 2 miles from Kirksville, MO, which stands at 970 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 63501 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°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.