Hingham, MT 59540 Frost Dates
Frost dates for Hingham, MT, ZIP 59540
Typically, the last spring freeze lands around 05/21, roughly 266 days out. The first fall frost typically arrives around 09/19, about 119 frost-free days later.
The USDA Plant Hardiness Zone Map puts Hingham in Zone 3b (-35 to -30°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 3b around Hingham has about 3 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Hingham's last frost
05/21 is the middle of 30 years of NOAA records, not a promise. Plant by 05/08 and you're betting against frost in roughly 9 years out of 10. 06/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hingham compares
Hingham's growing season runs about 119 days, ranking 39,192 of 40,283 US ZIP codes measured here, longest to shortest. Within MT, it ranks 227 of 392.
Learn more
the frost range explains how to read the range around Hingham's dates instead of trusting one, and local microclimates explains what one yard in Hingham can differ from the 59540 normal.