Simi Valley, CA 93063 Frost Dates
93063, near Simi Valley, CA: the frost window
Typically, the last spring freeze lands around 01/24, roughly 149 days out. Fall's first freeze usually shows up around 12/15, roughly 329 days after the last spring frost.
Simi Valley sits in USDA Zone 10a (30 to 35°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
Simi Valley's growing season runs out in roughly 16 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Simi Valley's last frost
01/24 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/05 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.
Simi Valley against the rest of the dataset
At roughly 329 frost-free days, Simi Valley places 3,072 of 40,283 ZIP codes in this dataset. Within CA, it ranks 1,325 of 2,555.
Learn more
Two guides worth reading on 93063: zone vs. frost date, on why Zone 10a and Simi Valley's frost date answer different questions, and the frost range, on how to read the range around Simi Valley's dates instead of trusting one.