Skip to content

USDA Hardiness Zone 6a

Frost Dates for 64156 — Kansas City, Missouri

NOAA 1991–2020 normals from Smithville Lake, MO (904 ft), 8 miles north.

Updated

In Kansas City, the last spring frost (32°F) is around April 18 in half of years and has passed by May 3 in nine years out of ten. The first fall frost comes around October 20, as early as October 5 one year in ten, leaving a typical freeze-free season of 183 days (NOAA, Smithville Lake, MO).

Last spring frost
April 18

50% probability

First fall frost
October 20

50% probability

Growing season
183 days

freeze-free, 50%

Hardiness zone
6a

-10 to -5°F (-23.3 to -20.6°C) coldest night

First snow
December 9

median, 1991–2020

Last snow
February 23

median, 1991–2020

Winters with snow
100%

26 of 26 observed

Snow per year
—

NOAA normal

Frost risk by date in Kansas City

Half of springs at Smithville Lake, MO see their last 32°F night by April 18; only one in ten is past it by April 4, and one in ten still has one after May 3. Planting tender crops after April 25 leaves a 30% risk of a frost on them, after April 29 20%, and after May 3 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 54% of the 158 Missouri stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 20 in half of years, as early as October 5 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 9 days later, around October 29; in spring the one-in-ten date for 28°F is April 23, 10 days before the 32°F one. The freeze-free season lasts 183 days in a typical year, shorter than at 85% of the 158 Missouri stations; it reaches 202 days one year in ten and falls short of 163 one year in ten. On average 119 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 28, and return around October 10. Severe cold of 16°F or below comes every winter, usually between November 27 and March 6.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 14Apr 18Apr 22Apr 25Apr 28Apr 30May 3May 7May 13
32°FApr 4Apr 8Apr 12Apr 15Apr 18Apr 22Apr 25Apr 29May 3
28°FMar 23Mar 30Apr 2Apr 4Apr 7Apr 10Apr 13Apr 18Apr 23
24°FMar 9Mar 16Mar 21Mar 25Mar 29Apr 1Apr 4Apr 8Apr 14
20°FFeb 28Mar 4Mar 8Mar 12Mar 16Mar 19Mar 23Mar 28Apr 3
16°FFeb 17Feb 24Feb 28Mar 3Mar 6Mar 9Mar 13Mar 18Mar 24
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FSep 25Sep 30Oct 4Oct 7Oct 10Oct 13Oct 16Oct 19Oct 23
32°FOct 5Oct 12Oct 15Oct 18Oct 20Oct 22Oct 25Oct 29Nov 1
28°FOct 15Oct 20Oct 24Oct 26Oct 29Oct 31Nov 2Nov 6Nov 11
24°FOct 22Oct 28Nov 1Nov 3Nov 5Nov 8Nov 12Nov 16Nov 23
20°FNov 1Nov 4Nov 8Nov 13Nov 16Nov 20Nov 24Nov 29Dec 4
16°FNov 7Nov 14Nov 18Nov 23Nov 27Dec 1Dec 3Dec 8Dec 15

Freeze probabilities 1991–2020 at Smithville Lake, 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 64156 →Compare Kansas City with another place →

Weather by month in Kansas City

July is the warmest month at Smithville Lake, MO, averaging 87°F by day and 68°F at night; January is the coldest at 36°F and 16°F. A freezing night is all but certain in every month from November 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 16% of years.

Warmth for growing adds up to 3,705 growing degree days a year (base 50°F), fewer than at 82% of the 158 Missouri stations. 35% of them (1,306) have built up by the end of June, and July adds the most, 838. Precipitation totals 40.3 inches a year, most in May (5.4") and least in January (1.2"); May to September bring 60% of it.

Monthly normals 1991–2020 at Smithville Lake, MO
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan36161.2100%291
Feb42211.4100%246
Mar53312.3100%1651
Apr64413.994%5160
May73535.416%<1408
Jun82635.30%0681
Jul87684.90%0838
Aug85664.40%0790
Sep78564.34%0512
Oct66443.588%4213
Nov53312.1100%1542
Dec42221.6100%263

Monthly normals 1991–2020 at Smithville Lake, MO (904 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, Kearney 3E, MO, 11 miles northeast of Kansas City, has a last frost 1 day later (April 19), a first frost 3 days earlier (October 17), a season 2 days shorter.

Frost dates for 64068 (Liberty) →

When it snows in Kansas City, Missouri

The first measurable snow (0.1 inch or more) in Kansas City usually arrives around December 9, and the last of the season around February 23. Those are the middle dates across the winters of 1991–2020 at Smithville Lake, MO, 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 54 days after the last snow.

Planting calendar for 64156

What to do and when, from the 50% frost dates for Kansas City, Missouri
WhenWhat to do
February 7 – February 21Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 21 – March 7Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 21 – April 4Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 18 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 28Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 6Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 20 onwardPlant 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 64156 is 8 miles from Smithville Lake, MO, which stands at 904 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 64155 (Kansas City). The 2023 USDA Plant Hardiness Zone Map lists ZIP 64156 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.

Frost dates across Missouri →

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.

ZIP codes measured at the same station

Other zone 6a places in Missouri