Dutton, MT 59468 Frost Dates
59468, near Dutton, MT: the frost window
Around 06/02 is the usual last spring frost, about 278 days away. Fall's first freeze usually shows up around 09/10, roughly 96 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Dutton in Zone 4b (-25 to -20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Dutton's growing season runs out in roughly 2 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Dutton's last frost
06/02 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/21 and only about 1 year in 10 sees frost after that.
Dutton against the rest of the dataset
About 96 days separate Dutton's last and first frost, putting it 39,803 of 40,283 ZIP codes nationally. Within MT, it ranks 328 of 392.
Learn more
Two guides worth reading on 59468: zone vs. frost date, on why Zone 4b and Dutton's frost date answer different questions, and the frost range, on how to read the range around Dutton's dates instead of trusting one.