Jackson, CA 95257 Frost Dates
95257, near Jackson, CA: the frost window
Typically, the last spring freeze lands around 05/07, roughly 252 days out. Fall's first freeze usually shows up around 10/28, roughly 169 days after the last spring frost.
Zone 8b (15 to 20°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 Jackson, not a forecast for this year.
Stretching the season past the first frost
Jackson's growing season runs out in roughly 9 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Jackson's last frost
05/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/31 and only about 1 year in 10 sees frost after that.
Jackson against the rest of the dataset
At roughly 169 frost-free days, Jackson places 29,414 of 40,283 ZIP codes in this dataset. Within CA, it ranks 2,394 of 2,555.
Learn more
Two guides worth reading on 95257: the frost range, on how to read the range around Jackson's dates instead of trusting one, and local microclimates, on what one yard in Jackson can differ from the 95257 normal.