Twin Falls, ID 83301 Frost Dates
83301, near Twin Falls, ID: the frost window
Typically, the last spring freeze lands around 05/09, roughly 254 days out. Fall's first freeze usually shows up around 10/04, roughly 147 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Twin Falls in Zone 6b (-5 to 0°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
Twin Falls'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.
How much risk comes with planting early here
05/09 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 05/28 and only about 1 year in 10 sees frost after that.
Twin Falls against the rest of the dataset
Twin Falls's growing season runs about 147 days, ranking 35,835 of 40,283 US ZIP codes measured here, longest to shortest. Within ID, it ranks 129 of 320.
Learn more
Two guides worth reading on 83301: zone vs. frost date, on why Zone 6b and Twin Falls's frost date answer different questions, and the frost range, on how to read the range around Twin Falls's dates instead of trusting one.