Tappen, ND 58487 Frost Dates
Frost dates for Tappen, ND, ZIP 58487
Around 05/14 is the usual last spring frost, about 259 days away. The first fall frost typically arrives around 09/27, about 135 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 Tappen, not a forecast for this year.
What to do before the first frost
Zone 4a around Tappen 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.
How much risk comes with planting early here
05/14 is the middle of 30 years of NOAA records, not a promise. Plant by 05/02 and you're betting against frost in roughly 9 years out of 10. 05/26 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Tappen compares
About 135 days separate Tappen's last and first frost, putting it 37,924 of 40,283 ZIP codes nationally. Within ND, it ranks 265 of 405.
Learn more
zone vs. frost date explains why Zone 4a and Tappen's frost date answer different questions, and the frost range explains how to read the range around Tappen's dates instead of trusting one.