Fairfield, ID 83322 Frost Dates
Fairfield, ID: when does the frost end?
Typically, the last spring freeze lands around 06/08, roughly 284 days out. Fall's first freeze usually shows up around 09/14, roughly 97 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Fairfield in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 2 weeks until Fairfield's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 06/08 isn't a guarantee
06/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/15 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/28 and only about 1 year in 10 sees frost after that.
Fairfield against the rest of the dataset
At roughly 97 frost-free days, Fairfield places 39,783 of 40,283 ZIP codes in this dataset. Within ID, it ranks 254 of 320.
Learn more
Before leaning on 83322's figures: local microclimates explains what one yard in Fairfield can differ from the 83322 normal, while zone vs. frost date explains why Zone 5a and Fairfield's frost date answer different questions.