Boulder, UT 84716 Frost Dates
Frost dates for Boulder, UT, ZIP 84716
Around 05/04 is the usual last spring frost, about 249 days away. The first fall frost typically arrives around 10/14, about 160 frost-free days later.
Boulder sits in USDA Zone 7a (0 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.
What to do before the first frost
Zone 7a around Boulder has about 7 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.
How much risk comes with planting early here
05/04 is the middle of 30 years of NOAA records, not a promise. Plant by 04/20 and you're betting against frost in roughly 9 years out of 10. 05/25 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Boulder compares
At roughly 160 frost-free days, Boulder places 32,519 of 40,283 ZIP codes in this dataset. Within UT, it ranks 157 of 344.
Learn more
the frost range explains how to read the range around Boulder's dates instead of trusting one, and local microclimates explains what one yard in Boulder can differ from the 84716 normal.