Highland, CA 92346 Frost Dates
Highland, CA: when does the frost end?
Around 01/27 is the usual last spring frost, about 152 days away. Fall's first freeze usually shows up around 12/19, roughly 329 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Highland in Zone 10a (30 to 35°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
With roughly 16 weeks until Highland's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 01/27 isn't a guarantee
01/27 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/21 and only about 1 year in 10 sees frost after that.
Highland against the rest of the dataset
Highland's growing season runs about 329 days, ranking 3,084 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,337 of 2,555.
Learn more
Before leaning on 92346's figures: zone vs. frost date explains why Zone 10a and Highland's frost date answer different questions, while the frost range explains how to read the range around Highland's dates instead of trusting one.