Poway, CA 92138 Frost Dates
92138, near Poway, CA: the frost window
The last spring frost here typically falls around 03/04, about 188 days from today. Fall's first freeze usually shows up around 12/04, roughly 270 days after the last spring frost.
Poway sits in USDA Zone 11a (40 to 45°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
Poway's growing season runs out in roughly 14 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 03/04 isn't a guarantee
03/04 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/29 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/10 and only about 1 year in 10 sees frost after that.
Poway against the rest of the dataset
Poway's growing season runs about 270 days, ranking 5,521 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,941 of 2,555.
Learn more
Two guides worth reading on 92138: the frost range, on how to read the range around Poway's dates instead of trusting one, and local microclimates, on what one yard in Poway can differ from the 92138 normal.