Mesa, AZ 85209 Frost Dates
Mesa, AZ: when does the frost end?
Typically, the last spring freeze lands around 02/01, roughly 157 days out. Fall's first freeze usually shows up around 12/10, roughly 312 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 Mesa, not a forecast for this year.
Stretching the season past the first frost
With roughly 15 weeks until Mesa's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
02/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/01 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 02/28 and only about 1 year in 10 sees frost after that.
Mesa against the rest of the dataset
At roughly 312 frost-free days, Mesa places 3,455 of 40,283 ZIP codes in this dataset. Within AZ, it ranks 227 of 506.
Learn more
Before leaning on 85209's figures: the frost range explains how to read the range around Mesa's dates instead of trusting one, while local microclimates explains what one yard in Mesa can differ from the 85209 normal.