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USDA Hardiness Zone 3b

Frost Dates for 56671 — Red Lake, Minnesota

NOAA 1991–2020 normals from Red Lake Indian Agcy, MN (1,216 ft), 6 miles east.

Updated

In Red Lake, the last spring frost (32°F) is around May 12 in half of years and has passed by May 30 in nine years out of ten. The first fall frost comes around October 4, as early as September 19 one year in ten, leaving a typical freeze-free season of 142 days (NOAA, Red Lake Indian Agcy, MN).

Last spring frost
May 12

50% probability

First fall frost
October 4

50% probability

Growing season
142 days

freeze-free, 50%

Hardiness zone
3b

-35 to -30°F (-37.2 to -34.4°C) coldest night

First snow
November 13

median, 1991–2020

Last snow
April 4

median, 1991–2020

Winters with snow
100%

21 of 21 observed

Snow per year
—

NOAA normal

Frost risk by date in Red Lake

Half of springs at Red Lake Indian Agcy, MN see their last 32°F night by May 12; only one in ten is past it by April 29, and one in ten still has one after May 30. Planting tender crops after May 19 leaves a 30% risk of a frost on them, after May 23 20%, and after May 30 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 92% of the 142 Minnesota stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 4 in half of years, as early as September 19 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 11 days later, around October 15; in spring the one-in-ten date for 28°F is May 19, 11 days before the 32°F one. The freeze-free season lasts 142 days in a typical year, shorter than at 73% of the 142 Minnesota stations; it reaches 164 days one year in ten and falls short of 119 one year in ten. On average 187 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 23, and return around September 24. Severe cold of 16°F or below comes every winter, usually between November 10 and April 7.

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

Freeze probabilities 1991–2020 at Red Lake Indian Agcy, MN, 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 56671 →Compare Red Lake with another place →

Weather by month in Red Lake

July is the warmest month at Red Lake Indian Agcy, MN, averaging 77°F by day and 60°F at night; January is the coldest at 16°F and -3°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 82% of years.

Warmth for growing adds up to 1,958 growing degree days a year (base 50°F), fewer than at 82% of the 142 Minnesota stations. 30% of them (590) have built up by the end of June, and July adds the most, 563. Precipitation totals 22.8 inches a year, most in June (3.6") and least in December (0.4"); May to September bring 67% of it.

Monthly normals 1991–2020 at Red Lake Indian Agcy, MN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan16-31.0100%310
Feb2110.6100%280
Mar34150.8100%292
Apr48291.3100%2121
May62432.982%5170
Jun72543.68%<1397
Jul77603.50%<1563
Aug76572.80%<1512
Sep66482.539%2242
Oct51362.399%1448
Nov34211.1100%273
Dec2160.4100%310

Monthly normals 1991–2020 at Red Lake Indian Agcy, MN (1,216 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, Blackduck, MN, 32 miles southeast of Red Lake, has a last frost 12 days later (May 24), a first frost 17 days earlier (September 17), a season 27 days shorter.

Frost dates for 56630 (Blackduck) →

When it snows in Red Lake, Minnesota

The first measurable snow (0.1 inch or more) in Red Lake usually arrives around November 13, and the last of the season around April 4. Those are the middle dates across the winters of 1991–2020 at Red Lake Indian Agcy, MN, 5.9 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 38 days after the last snow.

Planting calendar for 56671

What to do and when, from the 50% frost dates for Red Lake, Minnesota
WhenWhat to do
March 3 – March 17Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 17 – March 31Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 14 – April 28Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 12 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 12Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 20Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 4 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 56671 is 6 miles from Red Lake Indian Agcy, MN, which stands at 1,216 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 56671 in zone 3b, the band where the coldest night of the year averaged -35 to -30°F (-37.2 to -34.4°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Minnesota →

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.

Other zone 3b places in Minnesota