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USDA Hardiness Zone 6a

Frost Dates for 48741 — Kingston, Michigan

NOAA 1991–2020 normals from Caro Wwtp, MI (690 ft), 12 miles northwest.

Updated

In Kingston, the last spring frost (32°F) is around May 7 in half of years and has passed by May 24 in nine years out of ten. The first fall frost comes around October 9, as early as September 25 one year in ten, leaving a typical freeze-free season of 154 days (NOAA, Caro Wwtp, MI).

Last spring frost
May 7

50% probability

First fall frost
October 9

50% probability

Growing season
154 days

freeze-free, 50%

Hardiness zone
6a

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

First snow
November 25

median, 1991–2020

Last snow
April 2

median, 1991–2020

Winters with snow
100%

23 of 23 observed

Snow per year
41.6"

NOAA normal

Frost risk by date in Kingston

Half of springs at Caro Wwtp, MI see their last 32°F night by May 7; only one in ten is past it by April 24, and one in ten still has one after May 24. Planting tender crops after May 15 leaves a 30% risk of a frost on them, after May 19 20%, and after May 24 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 62% of the 172 Michigan stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 9 in half of years, as early as September 25 one year in ten, and holds off past October 26 one year in ten. A hard freeze of 28°F follows 14 days later, around October 23; in spring the one-in-ten date for 28°F is May 15, 9 days before the 32°F one. The freeze-free season lasts 154 days in a typical year, shorter than at 60% of the 172 Michigan stations; it reaches 175 days one year in ten and falls short of 133 one year in ten. On average 152 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 13 days longer, to about May 20, and return around October 1. Severe cold of 16°F or below comes every winter, usually between November 29 and March 25.

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

Freeze probabilities 1991–2020 at Caro Wwtp, MI, 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 48741 →Compare Kingston with another place →

Weather by month in Kingston

July is the warmest month at Caro Wwtp, MI, averaging 82°F by day and 60°F at night; January is the coldest at 29°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 August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 69% of years.

Warmth for growing adds up to 2,488 growing degree days a year (base 50°F), more than at 52% of the 172 Michigan stations. 32% of them (792) have built up by the end of June, and July adds the most, 643. Precipitation totals 34.3 inches a year, most in May (3.7") and least in February (1.6"); May to September bring 50% of it.

Monthly normals 1991–2020 at Caro Wwtp, MI
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan29152.2100%290
Feb32151.6100%270
Mar42231.9100%2611
Apr55343.6100%1554
May68453.769%2236
Jun78553.62%0491
Jul82603.50%0643
Aug80573.30%0578
Sep73503.220%1353
Oct60403.194%7107
Nov46312.5100%1915
Dec35222.1100%271

Monthly normals 1991–2020 at Caro Wwtp, MI (690 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, Cass City 1 SSW, MI, 12 miles north of Kingston, has the same 50% last-frost date, a first frost 1 day later (October 10), a season 2 days shorter.

Frost dates for 48726 (Cass City) →

When it snows in Kingston, Michigan

The first measurable snow (0.1 inch or more) in Kingston usually arrives around November 25, and the last of the season around April 2. Those are the middle dates across the winters of 1991–2020 at Caro Wwtp, MI, 12.1 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 35 days after the last snow.

Planting calendar for 48741

What to do and when, from the 50% frost dates for Kingston, Michigan
WhenWhat to do
February 26 – March 12Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 12 – March 26Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 9 – April 23Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 7 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 17Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 25Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 9 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 48741 is 12 miles from Caro Wwtp, MI, which stands at 690 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 48723 (Caro). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48741 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 Michigan →

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 Michigan