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USDA Hardiness Zone 4a

Frost Dates for 58104 — Fargo, North Dakota

NOAA 1991–2020 normals from Fargo 3S, ND (908 ft), 2 miles northeast.

Updated

In Fargo, the last spring frost (32°F) is around May 4 in half of years and has passed by May 18 in nine years out of ten. The first fall frost comes around October 2, as early as September 22 one year in ten, leaving a typical freeze-free season of 151 days (NOAA, Fargo 3S, ND).

Last spring frost
May 4

50% probability

First fall frost
October 2

50% probability

Growing season
151 days

freeze-free, 50%

Hardiness zone
4a

-30 to -25°F (-34.4 to -31.7°C) coldest night

First snow
November 5

median, 1991–2020

Last snow
April 12

median, 1991–2020

Winters with snow
100%

18 of 18 observed

Snow per year
52.7"

NOAA normal

Frost risk by date in Fargo

Half of springs at Fargo 3S, ND see their last 32°F night by May 4; only one in ten is past it by April 21, and one in ten still has one after May 18. Planting tender crops after May 9 leaves a 30% risk of a frost on them, after May 13 20%, and after May 18 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 82% of the 33 North Dakota stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 2 in half of years, as early as September 22 one year in ten, and holds off past October 15 one year in ten. A hard freeze of 28°F follows 10 days later, around October 12; in spring the one-in-ten date for 28°F is May 9, 9 days before the 32°F one. The freeze-free season lasts 151 days in a typical year, longer than at 91% of the 33 North Dakota stations; it reaches 167 days one year in ten and falls short of 133 one year in ten. On average 183 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 9 days longer, to about May 13, and return around September 24. Severe cold of 16°F or below comes every winter, usually between November 9 and April 1.

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

Freeze probabilities 1991–2020 at Fargo 3S, ND, 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 58104 →Compare Fargo with another place →

Compared with the next station

The nearest other station, Moorhead, MN, 7 miles northeast of Fargo, has a last frost 1 day later (May 5), a first frost 1 day later (October 3), a season 1 day shorter.

Frost dates for 56560 (Moorhead) →

When it snows in Fargo, North Dakota

The first measurable snow (0.1 inch or more) in Fargo usually arrives around November 5, and the last of the season around April 12. Those are the middle dates across the winters of 1991–2020 at Moorhead, MN, 6.7 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 22 days after the last snow.

Planting calendar for 58104

What to do and when, from the 50% frost dates for Fargo, North Dakota
WhenWhat to do
February 23 – March 9Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 9 – March 23Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 6 – April 20Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 4 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 10Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 18Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 2 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 58104 is 2 miles from Fargo 3S, ND, which stands at 908 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 58103 (Fargo). The 2023 USDA Plant Hardiness Zone Map lists ZIP 58104 in zone 4a, the band where the coldest night of the year averaged -30 to -25°F (-34.4 to -31.7°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across North Dakota →

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 4a places in North Dakota