Lodge Grass, MT 59031 Frost Dates
59031, near Lodge Grass, MT: the frost window
Around 05/13 is the usual last spring frost, about 258 days away. Fall's first freeze usually shows up around 09/29, roughly 135 days after the last spring frost.
Lodge Grass sits in USDA Zone 4b (-25 to -20°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
Lodge Grass's growing season runs out in roughly 5 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 Lodge Grass's last frost
05/13 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/30 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/26 and only about 1 year in 10 sees frost after that.
Lodge Grass against the rest of the dataset
About 135 days separate Lodge Grass's last and first frost, putting it 37,912 of 40,283 ZIP codes nationally. Within MT, it ranks 104 of 392.
Learn more
Two guides worth reading on 59031: zone vs. frost date, on why Zone 4b and Lodge Grass's frost date answer different questions, and the frost range, on how to read the range around Lodge Grass's dates instead of trusting one.