Bow Mar, CO 80235 Frost Dates
80235, near Bow Mar, CO: the frost window
The last spring frost here typically falls around 05/02, about 247 days from today. Fall's first freeze usually shows up around 10/11, roughly 160 days after the last spring frost.
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 Bow Mar, not a forecast for this year.
Stretching the season past the first frost
Bow Mar's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/02 isn't a guarantee
05/02 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/20 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/17 and only about 1 year in 10 sees frost after that.
Bow Mar against the rest of the dataset
At roughly 160 frost-free days, Bow Mar places 32,453 of 40,283 ZIP codes in this dataset. Within CO, it ranks 106 of 624.
Learn more
Two guides worth reading on 80235: zone vs. frost date, on why Zone 6a and Bow Mar's frost date answer different questions, and the frost range, on how to read the range around Bow Mar's dates instead of trusting one.