Portage, UT 84331 Frost Dates
Frost dates for Portage, UT, ZIP 84331
Typically, the last spring freeze lands around 05/17, roughly 262 days out. The first fall frost typically arrives around 09/24, about 128 frost-free days later.
The USDA Plant Hardiness Zone Map puts Portage in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 6a around Portage has about 4 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Portage's last frost
05/17 is the middle of 30 years of NOAA records, not a promise. Plant by 05/05 and you're betting against frost in roughly 9 years out of 10. 06/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Portage compares
About 128 days separate Portage's last and first frost, putting it 38,576 of 40,283 ZIP codes nationally. Within UT, it ranks 256 of 344.
Learn more
the frost range explains how to read the range around Portage's dates instead of trusting one, and local microclimates explains what one yard in Portage can differ from the 84331 normal.