New Rockford, ND 58356 Frost Dates
Frost dates for New Rockford, ND, ZIP 58356
The last spring frost here typically falls around 05/12, about 257 days from today. The first fall frost typically arrives around 09/27, about 137 frost-free days later.
Zone 4a (-30 to -25°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for New Rockford, not a forecast for this year.
What to do before the first frost
Zone 4a around New Rockford has about 4 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.
Why 05/12 isn't a guarantee
05/12 is the middle of 30 years of NOAA records, not a promise. Plant by 04/30 and you're betting against frost in roughly 9 years out of 10. 05/25 is the safer bet, historically only a 1-in-10 chance of frost that late.
How New Rockford compares
At roughly 137 frost-free days, New Rockford places 37,525 of 40,283 ZIP codes in this dataset. Within ND, it ranks 210 of 405.
Learn more
the frost range explains how to read the range around New Rockford's dates instead of trusting one, and local microclimates explains what one yard in New Rockford can differ from the 58356 normal.