Fortuna, ND 58844 Frost Dates
Frost dates for Fortuna, ND, ZIP 58844
The last spring frost here typically falls around 05/19, about 264 days from today. The first fall frost typically arrives around 09/17, about 121 frost-free days later.
Fortuna sits in USDA Zone 3b (-35 to -30°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 3b around Fortuna has about 3 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
05/19 is the middle of 30 years of NOAA records, not a promise. Plant by 05/08 and you're betting against frost in roughly 9 years out of 10. 05/31 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Fortuna compares
Fortuna's growing season runs about 121 days, ranking 39,064 of 40,283 US ZIP codes measured here, longest to shortest. Within ND, it ranks 390 of 405.
Learn more
zone vs. frost date explains why Zone 3b and Fortuna's frost date answer different questions, and the frost range explains how to read the range around Fortuna's dates instead of trusting one.