Ekalaka, MT 59354 Frost Dates
59354, near Ekalaka, MT: the frost window
The last spring frost here typically falls around 05/20, about 265 days from today. Fall's first freeze usually shows up around 09/23, roughly 126 days after the last spring frost.
Zone 4b (-25 to -20°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 Ekalaka, not a forecast for this year.
Stretching the season past the first frost
Ekalaka's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/20 isn't a guarantee
05/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/07 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/01 and only about 1 year in 10 sees frost after that.
Ekalaka against the rest of the dataset
At roughly 126 frost-free days, Ekalaka places 38,714 of 40,283 ZIP codes in this dataset. Within MT, it ranks 165 of 392.
Learn more
Two guides worth reading on 59354: zone vs. frost date, on why Zone 4b and Ekalaka's frost date answer different questions, and the frost range, on how to read the range around Ekalaka's dates instead of trusting one.