Fromberg, MT 59026 Frost Dates
Fromberg, MT: when does the frost end?
The last spring frost here typically falls around 05/14, about 259 days from today. Fall's first freeze usually shows up around 09/24, roughly 129 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Fromberg in Zone 5a (-20 to -15°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
With roughly 4 weeks until Fromberg's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/14 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/02 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/30 and only about 1 year in 10 sees frost after that.
Fromberg against the rest of the dataset
At roughly 129 frost-free days, Fromberg places 38,489 of 40,283 ZIP codes in this dataset. Within MT, it ranks 141 of 392.
Learn more
Before leaning on 59026's figures: the frost range explains how to read the range around Fromberg's dates instead of trusting one, while local microclimates explains what one yard in Fromberg can differ from the 59026 normal.