South Tucson, AZ 85757 Frost Dates
85757, near South Tucson, AZ: the frost window
The last spring frost here typically falls around 02/05, about 161 days from today. Fall's first freeze usually shows up around 12/09, roughly 307 days after the last spring frost.
South Tucson 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
South Tucson's growing season runs out in roughly 15 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 South Tucson's last frost
02/05 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/02 and only about 1 year in 10 sees frost after that.
South Tucson against the rest of the dataset
About 307 days separate South Tucson's last and first frost, putting it 3,679 of 40,283 ZIP codes nationally. Within AZ, it ranks 240 of 506.
Learn more
Two guides worth reading on 85757: the frost range, on how to read the range around South Tucson's dates instead of trusting one, and local microclimates, on what one yard in South Tucson can differ from the 85757 normal.