Fargo, North Dakota, United States

Frost dates for Fargo

The full distribution rather than a single date. Every figure below is a percentile of 30 years of daily minimum temperatures at this location, expressed as the date it fell on.

Median last spring frost

9 May

Half of years are later than this. Not a planting date.

Median first autumn frost

8 October

The far end of the outdoor season.

Frost-free season

152 days

Between those two dates in a median year.

Last and first frost by severity

Read a row as: in this fraction of years, the last frost of spring had already happened by this date. The 90% column is the cautious planting date; the 10% column is the gamble.

Light frost — nights at or below 0°C (32°F). Air temperature reaches freezing. Kills basil, beans and unhardened tomatoes; hardy crops shrug it off.
Frost 1 year in 10 Median 9 years in 10 Earliest Latest
Last of spring 18 Apr 9 May 16 May 10 Apr 21 May
First of autumn 25 Sep 8 Oct 17 Oct 20 Sep 22 Oct
Frost-free days 182 152 132 every year on record saw this
Moderate frost — nights at or below -2.2°C (28°F). Damages half-hardy plants and most blossom. This is the threshold that decides a fruit crop.
Frost 1 year in 10 Median 9 years in 10 Earliest Latest
Last of spring 16 Apr 25 Apr 13 May 8 Apr 15 May
First of autumn 4 Oct 14 Oct 28 Oct 30 Sep 3 Nov
Frost-free days 195 172 144 every year on record saw this
Hard frost — nights at or below -4.4°C (24.1°F). Ground freezes and even hardy crops check their growth. Effectively the end of the outdoor year.
Frost 1 year in 10 Median 9 years in 10 Earliest Latest
Last of spring 2 Apr 16 Apr 27 Apr 25 Mar 3 May
First of autumn 14 Oct 28 Oct 13 Nov 10 Oct 22 Nov
Frost-free days 225 195 170 every year on record saw this

Dates in the southern hemisphere are computed on a growing year that starts in July, which is why "last of spring" falls where it should rather than in the middle of the calendar.

Chance of frost, week by week

Jan Mar Apr Jul Sep Oct Dec
Chance of at least one air frost during each week of the year, measured across the full record. The flat stretch in the middle is your frost-free season.

Temperature through the year

J
F
M
A
M
J
J
A
S
O
N
D

Mean monthly temperature across the record. Months shown in blue average at least one air frost.

Monthly means and average number of frost nights.
Month Mean low Mean high Frost nights
January -17.6°C -7.7°C 30.9
February -15°C -4.2°C 27.9
March -6.9°C 4.6°C 27.7
April -0.2°C 13°C 15.6
May 7°C 20.4°C 2.1
June 13.3°C 25.8°C 0
July 16.2°C 29.1°C 0
August 14.9°C 28.3°C 0
September 10°C 23.2°C 0.2
October 2.3°C 13.7°C 10
November -5.2°C 3.7°C 25.8
December -13.1°C -4.7°C 30.9

Turn these dates into a planting calendar →

Nearby

Compare with places close by

Grand Forks Zone 3b 118 km Last frost 10 May First 6 Oct Saint Cloud Zone 4b 250 km Last frost 4 May First 8 Oct

Seasonal context

Rainfall and the growing season in Fargo

June has the highest average precipitation (104 mm); January has the lowest (14 mm). Compare this pattern with the planting windows and your water supply.

Jan 14 mm
Feb 16 mm
Mar 30 mm
Apr 45 mm
May 84 mm
Jun 104 mm
Jul 79 mm
Aug 70 mm
Sep 69 mm
Oct 57 mm
Nov 17 mm
Dec 24 mm

During wetter months, check that beds and containers drain after heavy rain. During drier months, plan how you will keep seeds and new transplants watered. Monthly averages can hide long dry spells and intense storms; they do not show soil moisture, humidity or this week's weather.

Source: NASA POWER, corrected MERRA-2 precipitation, 2001–2020. Values are approximate monthly totals, including the water equivalent of snow, from the nearest 0.5° × 0.625° grid cell. This reference period differs from the temperature record. Rainfall provides context and does not change the calculated planting dates. Method and limitations.

Plan your crops in My Garden