Judith Gap, MT 59453 Frost Dates
When can you plant in Judith Gap, MT?
Around 06/01 is the usual last spring frost, about 277 days away. The first fall frost typically arrives around 09/15, about 104 frost-free days later.
The USDA Plant Hardiness Zone Map puts Judith Gap in Zone 4b (-25 to -20°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
About 3 weeks of growing season left in Judith Gap before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
06/01 is the middle of 30 years of NOAA records, not a promise. Plant by 05/17 and you're betting against frost in roughly 9 years out of 10. 06/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Judith Gap compares
Judith Gap's growing season runs about 104 days, ranking 39,618 of 40,283 US ZIP codes measured here, longest to shortest. Within MT, it ranks 294 of 392.
Learn more
local microclimates covers what one yard in Judith Gap can differ from the 59453 normal. zone vs. frost date covers why Zone 4b and Judith Gap's frost date answer different questions.