Calipatria, CA 92257 Frost Dates
92257, near Calipatria, CA: the frost window
Typically, the last spring freeze lands around 02/20, roughly 176 days out. Fall's first freeze usually shows up around 11/30, roughly 283 days after the last spring frost.
Zone 9b (25 to 30°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 Calipatria, not a forecast for this year.
Stretching the season past the first frost
Calipatria's growing season runs out in roughly 13 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
02/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/19 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/20 and only about 1 year in 10 sees frost after that.
Calipatria against the rest of the dataset
At roughly 283 frost-free days, Calipatria places 4,745 of 40,283 ZIP codes in this dataset. Within CA, it ranks 1,745 of 2,555.
Learn more
Two guides worth reading on 92257: zone vs. frost date, on why Zone 9b and Calipatria's frost date answer different questions, and the frost range, on how to read the range around Calipatria's dates instead of trusting one.