Palo Alto, CA 94304 Frost Dates
Palo Alto, CA: when does the frost end?
Around 02/01 is the usual last spring frost, about 157 days away. Fall's first freeze usually shows up around 12/07, roughly 310 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Palo Alto in Zone 9b (25 to 30°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 14 weeks until Palo Alto's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Palo Alto's last frost
02/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/28 and only about 1 year in 10 sees frost after that.
Palo Alto against the rest of the dataset
About 310 days separate Palo Alto's last and first frost, putting it 3,549 of 40,283 ZIP codes nationally. Within CA, it ranks 1,469 of 2,555.
Learn more
Before leaning on 94304's figures: zone vs. frost date explains why Zone 9b and Palo Alto's frost date answer different questions, while the frost range explains how to read the range around Palo Alto's dates instead of trusting one.