Plentywood, MT 59211 Frost Dates
Frost dates for Plentywood, MT, ZIP 59211
Around 05/25 is the usual last spring frost, about 270 days away. The first fall frost typically arrives around 09/14, about 111 frost-free days later.
Plentywood 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 Plentywood has about 2 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.
The actual range around Plentywood's last frost
05/25 is the middle of 30 years of NOAA records, not a promise. Plant by 05/13 and you're betting against frost in roughly 9 years out of 10. 06/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Plentywood compares
About 111 days separate Plentywood's last and first frost, putting it 39,465 of 40,283 ZIP codes nationally. Within MT, it ranks 273 of 392.
Learn more
the frost range explains how to read the range around Plentywood's dates instead of trusting one, and local microclimates explains what one yard in Plentywood can differ from the 59211 normal.