Sonora, CA 95311 Frost Dates
Sonora, CA: when does the frost end?
Typically, the last spring freeze lands around 04/22, roughly 237 days out. Fall's first freeze usually shows up around 11/02, roughly 192 days after the last spring frost.
Sonora sits in USDA Zone 8b (15 to 20°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 9 weeks until Sonora's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/22 isn't a guarantee
04/22 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/05 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/14 and only about 1 year in 10 sees frost after that.
Sonora against the rest of the dataset
About 192 days separate Sonora's last and first frost, putting it 20,288 of 40,283 ZIP codes nationally. Within CA, it ranks 2,302 of 2,555.
Learn more
Before leaning on 95311's figures: zone vs. frost date explains why Zone 8b and Sonora's frost date answer different questions, while the frost range explains how to read the range around Sonora's dates instead of trusting one.