Portola, CA 96106 Frost Dates
Portola, CA: when does the frost end?
The last spring frost here typically falls around 06/11, about 287 days from today. Fall's first freeze usually shows up around 09/10, roughly 91 days after the last spring frost.
Portola sits in USDA Zone 7a (0 to 5°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 2 weeks until Portola's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Portola's last frost
06/11 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/25 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 07/02 and only about 1 year in 10 sees frost after that.
Portola against the rest of the dataset
About 91 days separate Portola's last and first frost, putting it 39,899 of 40,283 ZIP codes nationally. Within CA, it ranks 2,533 of 2,555.
Learn more
Before leaning on 96106's figures: zone vs. frost date explains why Zone 7a and Portola's frost date answer different questions, while the frost range explains how to read the range around Portola's dates instead of trusting one.