Jamestown, CO 80314 Frost Dates
When can you plant in Jamestown, CO?
Typically, the last spring freeze lands around 05/06, roughly 251 days out. The first fall frost typically arrives around 10/05, about 151 frost-free days later.
Jamestown 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.
What to do before the first frost
About 5 weeks of growing season left in Jamestown before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Jamestown's last frost
05/06 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 Jamestown compares
About 151 days separate Jamestown's last and first frost, putting it 35,172 of 40,283 ZIP codes nationally. Within CO, it ranks 319 of 624.
Learn more
local microclimates covers what one yard in Jamestown can differ from the 80314 normal. zone vs. frost date covers why Zone 6a and Jamestown's frost date answer different questions.