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USDA Hardiness Zone 6a

Frost Dates for 49030 — Burr Oak, Michigan

NOAA 1991–2020 normals from Lagrange, IN (900 ft), 15 miles south.

Updated

In Burr Oak, the last spring frost (32°F) is around April 26 in half of years and has passed by May 14 in nine years out of ten. The first fall frost comes around October 21, as early as October 5 one year in ten, leaving a typical freeze-free season of 176 days (NOAA, Lagrange, IN).

Last spring frost
April 26

50% probability

First fall frost
October 21

50% probability

Growing season
176 days

freeze-free, 50%

Hardiness zone
6a

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

First snow
November 23

median, 1991–2020

Last snow
March 26

median, 1991–2020

Winters with snow
100%

30 of 30 observed

Snow per year
41.2"

NOAA normal

Frost risk by date in Burr Oak

Half of springs at Lagrange, IN see their last 32°F night by April 26; only one in ten is past it by April 13, and one in ten still has one after May 14. Planting tender crops after May 2 leaves a 30% risk of a frost on them, after May 6 20%, and after May 14 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 81% of the 172 Michigan 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 5 one year in ten, and holds off past November 2 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 30, 14 days before the 32°F one. The freeze-free season lasts 176 days in a typical year, longer than at 90% of the 172 Michigan stations; it reaches 197 days one year in ten and falls short of 154 one year in ten. On average 140 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 May 6, and return around October 8. Severe cold of 16°F or below comes every winter, usually between December 1 and March 15.

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

Freeze probabilities 1991–2020 at Lagrange, 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 49030 →Compare Burr Oak with another place →

Weather by month in Burr Oak

July is the warmest month at Lagrange, IN, averaging 83°F by day and 62°F at night; January is the coldest at 31°F and 17°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 34% of years.

Warmth for growing adds up to 2,935 growing degree days a year (base 50°F), more than at 94% of the 172 Michigan stations. 34% of them (1,011) have built up by the end of June, and July adds the most, 690. Precipitation totals 38.5 inches a year, most in May (4.3") and least in February (1.9"); May to September bring 50% of it.

Monthly normals 1991–2020 at Lagrange, IN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan31172.7100%291
Feb34181.9100%251
Mar45272.5100%2424
Apr59383.699%1098
May70494.334%1320
Jun80584.10%0569
Jul83623.40%0690
Aug81604.20%0637
Sep75533.13%<1421
Oct62433.484%6150
Nov48313.0100%1824
Dec36232.3100%272

Monthly normals 1991–2020 at Lagrange, IN (900 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, Three Rivers, MI, 17 miles west of Burr Oak, has a last frost 4 days later (April 30), a first frost 4 days earlier (October 17), a season 6 days shorter.

Frost dates for 49093 (Three Rivers) →

When it snows in Burr Oak, Michigan

The first measurable snow (0.1 inch or more) in Burr Oak usually arrives around November 23, and the last of the season around March 26. Those are the middle dates across the winters of 1991–2020 at Three Rivers, MI, 16.7 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 31 days after the last snow.

Planting calendar for 49030

What to do and when, from the 50% frost dates for Burr Oak, Michigan
WhenWhat to do
February 15 – March 1Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 1 – March 15Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 29 – April 12Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 26 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 49030 is 15 miles from Lagrange, IN, which stands at 900 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station; its figures are presented in full for 49091 (Sturgis). The 2023 USDA Plant Hardiness Zone Map lists ZIP 49030 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