Lewiston, UT 84320 Frost Dates
Lewiston, UT: when does the frost end?
The last spring frost here typically falls around 05/17, about 262 days from today. Fall's first freeze usually shows up around 09/18, roughly 121 days after the last spring frost.
Lewiston 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
With roughly 3 weeks until Lewiston'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
05/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/03 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/06 and only about 1 year in 10 sees frost after that.
Lewiston against the rest of the dataset
At roughly 121 frost-free days, Lewiston places 39,010 of 40,283 ZIP codes in this dataset. Within UT, it ranks 285 of 344.
Learn more
Before leaning on 84320's figures: the frost range explains how to read the range around Lewiston's dates instead of trusting one, while local microclimates explains what one yard in Lewiston can differ from the 84320 normal.