Midvale, ID 83645 Frost Dates
83645, near Midvale, ID: the frost window
Typically, the last spring freeze lands around 05/10, roughly 255 days out. Fall's first freeze usually shows up around 10/02, roughly 145 days after the last spring frost.
Midvale sits in USDA Zone 6a (-10 to -5°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Midvale's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/10 isn't a guarantee
05/10 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/25 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.
Midvale against the rest of the dataset
At roughly 145 frost-free days, Midvale places 36,286 of 40,283 ZIP codes in this dataset. Within ID, it ranks 141 of 320.
Learn more
Two guides worth reading on 83645: local microclimates, on what one yard in Midvale can differ from the 83645 normal, and zone vs. frost date, on why Zone 6a and Midvale's frost date answer different questions.