Brentwood, CA 94505 Frost Dates
Brentwood, CA: when does the frost end?
Typically, the last spring freeze lands around 01/19, roughly 144 days out. Fall's first freeze usually shows up around 12/10, roughly 330 days after the last spring frost.
Brentwood sits in USDA Zone 9b (25 to 30°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 15 weeks until Brentwood's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Brentwood's last frost
01/19 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/25 and only about 1 year in 10 sees frost after that.
Brentwood against the rest of the dataset
About 330 days separate Brentwood's last and first frost, putting it 2,999 of 40,283 ZIP codes nationally. Within CA, it ranks 1,312 of 2,555.
Learn more
Before leaning on 94505's figures: local microclimates explains what one yard in Brentwood can differ from the 94505 normal, while zone vs. frost date explains why Zone 9b and Brentwood's frost date answer different questions.