Irvine, CA 92650 Frost Dates
92650, near Irvine, CA: the frost window
Around 01/05 is the usual last spring frost, about 130 days away. Fall's first freeze usually shows up around 12/25, roughly 365 days after the last spring frost.
Zone 10b (35 to 40°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 Irvine, not a forecast for this year.
Stretching the season past the first frost
Irvine's growing season runs out in roughly 17 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
01/05 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/02 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/14 and only about 1 year in 10 sees frost after that.
Irvine against the rest of the dataset
Irvine's growing season runs about 365 days, ranking 258 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 53 of 2,555.
Learn more
Two guides worth reading on 92650: local microclimates, on what one yard in Irvine can differ from the 92650 normal, and zone vs. frost date, on why Zone 10b and Irvine's frost date answer different questions.