Rockvale, CO 81244 Frost Dates
Frost dates for Rockvale, CO, ZIP 81244
Typically, the last spring freeze lands around 05/04, roughly 249 days out. The first fall frost typically arrives around 10/07, about 153 frost-free days later.
Zone 6a (-10 to -5°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Rockvale, not a forecast for this year.
What to do before the first frost
Zone 6a around Rockvale has about 6 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.
Why 05/04 isn't a guarantee
05/04 is the middle of 30 years of NOAA records, not a promise. Plant by 04/24 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Rockvale compares
Rockvale's growing season runs about 153 days, ranking 34,598 of 40,283 US ZIP codes measured here, longest to shortest. Within CO, it ranks 280 of 624.
Learn more
local microclimates explains what one yard in Rockvale can differ from the 81244 normal, and zone vs. frost date explains why Zone 6a and Rockvale's frost date answer different questions.