Phoenix, AZ 85022 Frost Dates
Phoenix, AZ: when does the frost end?
Typically, the last spring freeze lands around 01/08, roughly 133 days out. Fall's first freeze usually shows up around 12/25, roughly 354 days after the last spring frost.
Zone 9b (25 to 30°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Phoenix, not a forecast for this year.
Stretching the season past the first frost
With roughly 17 weeks until Phoenix's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Phoenix's last frost
01/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/16 and only about 1 year in 10 sees frost after that.
Phoenix against the rest of the dataset
At roughly 354 frost-free days, Phoenix places 2,152 of 40,283 ZIP codes in this dataset. Within AZ, it ranks 40 of 506.
Learn more
Before leaning on 85022's figures: local microclimates explains what one yard in Phoenix can differ from the 85022 normal, while zone vs. frost date explains why Zone 9b and Phoenix's frost date answer different questions.