Somerton, AZ 85365 Frost Dates
85365, near Somerton, AZ: the frost window
Around 01/08 is the usual last spring frost, about 133 days away. Fall's first freeze usually shows up around 12/28, roughly 362 days after the last spring frost.
Somerton sits in USDA Zone 9a (20 to 25°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
Somerton's growing season runs out in roughly 17 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
01/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/19 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/17 and only about 1 year in 10 sees frost after that.
Somerton against the rest of the dataset
Somerton's growing season runs about 362 days, ranking 2,072 of 40,283 US ZIP codes measured here, longest to shortest. Within AZ, it ranks 24 of 506.
Learn more
Two guides worth reading on 85365: local microclimates, on what one yard in Somerton can differ from the 85365 normal, and zone vs. frost date, on why Zone 9a and Somerton's frost date answer different questions.