Bayfield, CO 81303 Frost Dates
81303, near Bayfield, CO: the frost window
Typically, the last spring freeze lands around 06/01, roughly 277 days out. Fall's first freeze usually shows up around 09/27, roughly 116 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Bayfield in Zone 6b (-5 to 0°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Bayfield's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 06/01 isn't a guarantee
06/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/15 and only about 1 year in 10 sees frost after that.
Bayfield against the rest of the dataset
About 116 days separate Bayfield's last and first frost, putting it 39,282 of 40,283 ZIP codes nationally. Within CO, it ranks 478 of 624.
Learn more
Two guides worth reading on 81303: the frost range, on how to read the range around Bayfield's dates instead of trusting one, and local microclimates, on what one yard in Bayfield can differ from the 81303 normal.