Smithfield, UT 84335 Frost Dates
84335, near Smithfield, UT: the frost window
Typically, the last spring freeze lands around 05/08, roughly 253 days out. Fall's first freeze usually shows up around 10/02, roughly 144 days after the last spring frost.
Smithfield 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
Smithfield'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 05/08 isn't a guarantee
05/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/29 and only about 1 year in 10 sees frost after that.
Smithfield against the rest of the dataset
About 144 days separate Smithfield's last and first frost, putting it 36,340 of 40,283 ZIP codes nationally. Within UT, it ranks 209 of 344.
Learn more
Two guides worth reading on 84335: the frost range, on how to read the range around Smithfield's dates instead of trusting one, and local microclimates, on what one yard in Smithfield can differ from the 84335 normal.