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USDA Hardiness Zone 5a

Frost Dates for 56073 — New Ulm, Minnesota

NOAA 1991–2020 normals from New Ulm 2 SE, MN (890 ft), 2 miles west.

Updated

In New Ulm, the last spring frost (32°F) is around April 29 in half of years and has passed by May 12 in nine years out of ten. The first fall frost comes around October 7, as early as September 22 one year in ten, leaving a typical freeze-free season of 161 days (NOAA, New Ulm 2 SE, MN).

Last spring frost
April 29

50% probability

First fall frost
October 7

50% probability

Growing season
161 days

freeze-free, 50%

Hardiness zone
5a

-20 to -15°F (-28.9 to -26.1°C) coldest night

First snow
November 6

median, 1991–2020

Last snow
April 8

median, 1991–2020

Winters with snow
100%

20 of 20 observed

Snow per year
38.3"

NOAA normal

Frost risk by date in New Ulm

Half of springs at New Ulm 2 SE, MN see their last 32°F night by April 29; only one in ten is past it by April 15, and one in ten still has one after May 12. Planting tender crops after May 4 leaves a 30% risk of a frost on them, after May 7 20%, and after May 12 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 61% of the 142 Minnesota stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 7 in half of years, as early as September 22 one year in ten, and holds off past October 23 one year in ten. A hard freeze of 28°F follows 14 days later, around October 21; in spring the one-in-ten date for 28°F is May 2, 10 days before the 32°F one. The freeze-free season lasts 161 days in a typical year, longer than at 79% of the 142 Minnesota stations; it reaches 180 days one year in ten and falls short of 141 one year in ten. On average 155 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 8 days longer, to about May 7, and return around September 28. Severe cold of 16°F or below comes every winter, usually between November 13 and March 22.

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

Freeze probabilities 1991–2020 at New Ulm 2 SE, 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 56073 →Compare New Ulm with another place →

Weather by month in New Ulm

July is the warmest month at New Ulm 2 SE, MN, averaging 82°F by day and 63°F at night; January is the coldest at 24°F and 7°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 45% of years.

Warmth for growing adds up to 2,767 growing degree days a year (base 50°F), more than at 89% of the 142 Minnesota stations. 34% of them (944) have built up by the end of June, and July adds the most, 693. Precipitation totals 31.1 inches a year, most in June (5.0") and least in January (0.7"); May to September bring 65% of it.

Monthly normals 1991–2020 at New Ulm 2 SE, MN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan2470.7100%310
Feb29110.9100%270
Mar41241.6100%258
Apr57362.9100%1075
May69494.145%1297
Jun79595.00%0564
Jul82634.10%0693
Aug80603.70%0611
Sep73523.327%1389
Oct60392.498%8118
Nov43261.5100%2313
Dec29130.9100%300

Monthly normals 1991–2020 at New Ulm 2 SE, MN (890 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, Gaylord, MN, 21 miles northeast of New Ulm, has a last frost 5 days earlier (April 24), a first frost 8 days later (October 15), a season 9 days longer.

Frost dates for 55307 (Arlington) →

When it snows in New Ulm, Minnesota

The first measurable snow (0.1 inch or more) in New Ulm usually arrives around November 6, and the last of the season around April 8. Those are the middle dates across the winters of 1991–2020 at New Ulm 2 SE, MN, 1.5 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 21 days after the last snow.

Planting calendar for 56073

What to do and when, from the 50% frost dates for New Ulm, Minnesota
WhenWhat to do
February 18 – March 4Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 4 – March 18Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 1 – April 15Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 29 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 15Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 23Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 7 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 56073 is 2 miles from New Ulm 2 SE, MN, which stands at 890 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 56073 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°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.

ZIP codes measured at the same station

Other zone 5a places in Minnesota