Ammon, ID 83427 Frost Dates
Ammon, ID: when does the frost end?
Typically, the last spring freeze lands around 06/09, roughly 285 days out. Fall's first freeze usually shows up around 09/11, roughly 93 days after the last spring frost.
Ammon sits in USDA Zone 5b (-15 to -10°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
With roughly 2 weeks until Ammon'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
06/09 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/19 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/26 and only about 1 year in 10 sees frost after that.
Ammon against the rest of the dataset
Ammon's growing season runs about 93 days, ranking 39,863 of 40,283 US ZIP codes measured here, longest to shortest. Within ID, it ranks 262 of 320.
Learn more
Before leaning on 83427's figures: the frost range explains how to read the range around Ammon's dates instead of trusting one, while local microclimates explains what one yard in Ammon can differ from the 83427 normal.