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USDA Hardiness Zone 6a

Frost Dates for 46050 — Kirklin, Indiana

NOAA 1991–2020 normals from Frankfort Disposal, IN (824 ft), 11 miles northwest.

Updated

In Kirklin, the last spring frost (32°F) is around April 21 in half of years and has passed by May 7 in nine years out of ten. The first fall frost comes around October 21, as early as October 6 one year in ten, leaving a typical freeze-free season of 181 days (NOAA, Frankfort Disposal, IN).

Last spring frost
April 21

50% probability

First fall frost
October 21

50% probability

Growing season
181 days

freeze-free, 50%

Hardiness zone
6a

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

First snow
December 1

median, 1991–2020

Last snow
March 10

median, 1991–2020

Winters with snow
100%

30 of 30 observed

Snow per year
24.1"

NOAA normal

Frost risk by date in Kirklin

Half of springs at Frankfort Disposal, IN 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 7. Planting tender crops after April 28 leaves a 30% risk of a frost on them, after May 1 20%, and after May 7 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 35% of the 125 Indiana stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 21 in half of years, as early as October 6 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 11 days later, around November 1; in spring the one-in-ten date for 28°F is April 23, 14 days before the 32°F one. The freeze-free season lasts 181 days in a typical year, shorter than at 50% of the 125 Indiana stations; it reaches 201 days one year in ten and falls short of 160 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 11 days longer, to about May 2, and return around October 10. Severe cold of 16°F or below comes every winter, usually between December 3 and March 7.

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

Freeze probabilities 1991–2020 at Frankfort Disposal, IN, 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 46050 →Compare Kirklin with another place →

Weather by month in Kirklin

July is the warmest month at Frankfort Disposal, IN, averaging 84°F by day and 64°F at night; January is the coldest at 34°F and 19°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 21% of years.

Warmth for growing adds up to 3,326 growing degree days a year (base 50°F), fewer than at 53% of the 125 Indiana stations. 36% of them (1,202) have built up by the end of June, and July adds the most, 732. Precipitation totals 43.4 inches a year, most in June (5.3") and least in February (2.5"); May to September bring 48% of it.

Monthly normals 1991–2020 at Frankfort Disposal, IN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan34193.0100%272
Feb38222.5100%244
Mar50313.1100%1940
Apr62414.196%6140
May73524.421%<1386
Jun81615.30%0630
Jul84644.80%0732
Aug82623.40%0685
Sep77543.13%<1476
Oct65443.387%3190
Nov50333.5100%1537
Dec39242.9100%255

Monthly normals 1991–2020 at Frankfort Disposal, IN (824 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, Tipton 5 SW, IN, 13 miles east of Kirklin, has a last frost 2 days later (April 23), a first frost 4 days earlier (October 17), a season 7 days shorter.

Frost dates for 46072 (Tipton) →

When it snows in Kirklin, Indiana

The first measurable snow (0.1 inch or more) in Kirklin usually arrives around December 1, and the last of the season around March 10. Those are the middle dates across the winters of 1991–2020 at Frankfort Disposal, IN, 10.6 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 42 days after the last snow.

Planting calendar for 46050

What to do and when, from the 50% frost dates for Kirklin, Indiana
WhenWhat to do
February 10 – February 24Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 24 – March 10Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 24 – April 7Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 21 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 29Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 7Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 21 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 46050 is 11 miles from Frankfort Disposal, IN, which stands at 824 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 46041 (Frankfort). The 2023 USDA Plant Hardiness Zone Map lists ZIP 46050 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 Indiana →

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 Indiana