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USDA Hardiness Zone 6b

Frost Dates for 66054 — Mc Louth, Kansas

NOAA 1991–2020 normals from Oskaloosa 4 NE, KS (1,109 ft), 5 miles northwest.

Updated

In Mc Louth, the last spring frost (32°F) is around April 16 in half of years and has passed by April 29 in nine years out of ten. The first fall frost comes around October 22, as early as October 5 one year in ten, leaving a typical freeze-free season of 188 days (NOAA, Oskaloosa 4 NE, KS).

Last spring frost
April 16

50% probability

First fall frost
October 22

50% probability

Growing season
188 days

freeze-free, 50%

Hardiness zone
6b

-5 to 0°F (-20.6 to -17.8°C) coldest night

First snow
December 8

median, 1991–2020

Last snow
February 27

median, 1991–2020

Winters with snow
100%

20 of 20 observed

Snow per year
16.4"

NOAA normal

Frost risk by date in Mc Louth

Half of springs at Oskaloosa 4 NE, KS see their last 32°F night by April 16; only one in ten is past it by April 2, and one in ten still has one after April 29. Planting tender crops after April 21 leaves a 30% risk of a frost on them, after April 24 20%, and after April 29 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 65% of the 110 Kansas stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 22 in half of years, as early as October 5 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 10 days later, around November 1; in spring the one-in-ten date for 28°F is April 21, 8 days before the 32°F one. The freeze-free season lasts 188 days in a typical year, shorter than at 48% of the 110 Kansas stations; it reaches 208 days one year in ten and falls short of 169 one year in ten. On average 113 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 25, and return around October 11. Severe cold of 16°F or below comes every winter, usually between November 28 and March 8.

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

Freeze probabilities 1991–2020 at Oskaloosa 4 NE, 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 66054 →Compare Mc Louth with another place →

Weather by month in Mc Louth

July is the warmest month at Oskaloosa 4 NE, KS, averaging 90°F by day and 68°F at night; January is the coldest at 38°F and 18°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month.

Warmth for growing adds up to 4,043 growing degree days a year (base 50°F), fewer than at 60% of the 110 Kansas stations. 36% of them (1,460) have built up by the end of June, and July adds the most, 899. Precipitation totals 38.4 inches a year, most in June (5.4") and least in January (1.0"); May to September bring 61% of it.

Monthly normals 1991–2020 at Oskaloosa 4 NE, KS
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan38181.0100%281
Feb45221.3100%229
Mar56312.5100%1559
Apr66423.592%5189
May76545.38%<1470
Jun85645.40%0733
Jul90684.50%0899
Aug88664.80%0835
Sep80573.45%0552
Oct68442.981%3245
Nov54322.0100%1447
Dec42221.8100%264

Monthly normals 1991–2020 at Oskaloosa 4 NE, KS (1,109 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, Perry Lake, KS, 13 miles southwest of Mc Louth and 152 feet lower, has a last frost 3 days earlier (April 13), a first frost 2 days later (October 24), a season 3 days longer.

Frost dates for 66073 (Perry) →

When it snows in Mc Louth, Kansas

The first measurable snow (0.1 inch or more) in Mc Louth usually arrives around December 8, and the last of the season around February 27. Those are the middle dates across the winters of 1991–2020 at Oskaloosa 4 NE, KS, 4.8 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 48 days after the last snow.

Planting calendar for 66054

What to do and when, from the 50% frost dates for Mc Louth, Kansas
WhenWhat to do
February 5 – February 19Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 19 – March 5Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 19 – April 2Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 16 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 30Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 8Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 22 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 66054 is 5 miles from Oskaloosa 4 NE, KS, which stands at 1,109 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 66066 (Oskaloosa). The 2023 USDA Plant Hardiness Zone Map lists ZIP 66054 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.

Frost dates across Kansas →

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 6b places in Kansas