Cortez, CO 81330 Frost Dates
Frost dates for Cortez, CO, ZIP 81330
Around 05/06 is the usual last spring frost, about 251 days away. The first fall frost typically arrives around 10/14, about 158 frost-free days later.
The USDA Plant Hardiness Zone Map puts Cortez in Zone 7a (0 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 7a around Cortez 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
05/06 is the middle of 30 years of NOAA records, not a promise. Plant by 04/22 and you're betting against frost in roughly 9 years out of 10. 05/27 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Cortez compares
At roughly 158 frost-free days, Cortez places 32,937 of 40,283 ZIP codes in this dataset. Within CO, it ranks 168 of 624.
Learn more
local microclimates explains what one yard in Cortez can differ from the 81330 normal, and zone vs. frost date explains why Zone 7a and Cortez's frost date answer different questions.