Plentywood, MT 59256 Frost Dates
Plentywood, MT: when does the frost end?
Around 05/25 is the usual last spring frost, about 270 days away. Fall's first freeze usually shows up around 09/14, roughly 111 days after the last spring frost.
Plentywood sits in USDA Zone 4a (-30 to -25°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.
Stretching the season past the first frost
With roughly 2 weeks until Plentywood's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Plentywood's last frost
05/25 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/13 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/08 and only about 1 year in 10 sees frost after that.
Plentywood against the rest of the dataset
About 111 days separate Plentywood's last and first frost, putting it 39,467 of 40,283 ZIP codes nationally. Within MT, it ranks 275 of 392.
Learn more
Before leaning on 59256's figures: the frost range explains how to read the range around Plentywood's dates instead of trusting one, while local microclimates explains what one yard in Plentywood can differ from the 59256 normal.