🌡️ Frost & Freeze Dates in Fargo-Moorhead
When's the first frost? When is it safe to plant? The odds from 35 years of Fargo's official weather record - plus tonight's forecast low, so you know whether to cover the tomatoes.
Forecast lows: National Weather Service. Badges use the frost/freeze warning levels of the NWS office in Grand Forks - the National Weather Service office that covers Fargo-Moorhead (below).
This fall: Fargo's first freeze of the season was October 2.
🍂 First fall frost in Fargo
Half of years have had their first freeze by Oct 6. It's come as early as Sep 10 and as late as Oct 24.
| 10% of years by | Median | 90% of years by | |
|---|---|---|---|
| First freeze (32°F) | Sep 20 | Oct 6 | Oct 16 |
| First hard freeze (28°F) | Sep 28 | Oct 14 | Oct 25 |
Chance Fargo has had its first freeze by...
🌱 Last spring frost in Fargo
Half of springs have had their last freeze by May 11 - but in 1 year out of 10, one still sneaks in after May 22. Waiting until after that date is the safer bet for tomatoes and other tender plants.
| 10% of years by | Median | 90% of years by | |
|---|---|---|---|
| Last freeze (32°F) | Apr 24 | May 11 | May 22 |
| Last hard freeze (28°F) | Apr 17 | Apr 28 | May 13 |
How to read these: each "by" column is the date by which it had happened in that share of years - e.g. "90% of years by May 22" means only 1 spring in 10 had a freeze after May 22. Computed from daily lows at Fargo Hector International Airport, 1991-2025. The National Weather Service in Grand Forks lists Fargo's average first fall freeze as Oct 2 and first 28°F as Oct 9 (1991-2020 averages); the medians above use a slightly different stat and a few more recent years, so they land a few days apart.
What the numbers mean
- Frost possible (33-36°F)
- The range where NWS Grand Forks issues a Frost Advisory during the growing season - frost can form on clear, calm nights even above freezing.
- Freeze (32°F or colder)
- NWS Grand Forks' Freeze Warning level. Tender plants (tomatoes, peppers, basil, annuals) are at risk.
- Hard freeze (28°F or colder)
- NWS Grand Forks' Hard Freeze Warning level - cold enough to kill most garden and crop plants and end the growing season.
One caveat, and it's our judgment rather than a measured number: these are the airport's temperatures. Low spots and open yards can run colder on calm nights, and spots near buildings warmer - so treat a forecast of 34-35°F as "cover them" if your garden sits low.
References
- NWS Grand Forks (the National Weather Service office for Fargo-Moorhead) - Watch, Warning, Advisory Criteria (frost/freeze levels)
- NWS Grand Forks - Frost/Freeze Information (official 1991-2020 average freeze dates)
- National Weather Service - Understanding Cold Weather Alerts and glossary: freeze (what freezes do to plants)
- NOAA Regional Climate Centers - ACIS daily data, Fargo Hector International Airport (the freeze-date statistics above)
- National Weather Service - forecast lows for the next few nights