FrostDateCheck

Montpelier, ID 83220 Frost Dates

Montpelier, ID: when does the frost end?

Zone 5a

The last spring frost here typically falls around 06/17, about 293 days from today. Fall's first freeze usually shows up around 09/03, roughly 77 days after the last spring frost.

Zone 5a (-20 to -15°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 Montpelier, not a forecast for this year.

Stretching the season past the first frost

With roughly 1 week until Montpelier's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.

Why 06/17 isn't a guarantee

06/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/31 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 07/04 and only about 1 year in 10 sees frost after that.

Montpelier against the rest of the dataset

At roughly 77 frost-free days, Montpelier places 40,072 of 40,283 ZIP codes in this dataset. Within ID, it ranks 288 of 320.

Learn more

Before leaning on 83220's figures: zone vs. frost date explains why Zone 5a and Montpelier's frost date answer different questions, while the frost range explains how to read the range around Montpelier's dates instead of trusting one.