Dewey-Humboldt, AZ 86343 Frost Dates
86343, near Dewey-Humboldt, AZ: the frost window
Around 04/05 is the usual last spring frost, about 220 days away. Fall's first freeze usually shows up around 11/17, roughly 221 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Dewey-Humboldt in Zone 8a (10 to 15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Dewey-Humboldt's growing season runs out in roughly 12 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 Dewey-Humboldt's last frost
04/05 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/09 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/24 and only about 1 year in 10 sees frost after that.
Dewey-Humboldt against the rest of the dataset
Dewey-Humboldt's growing season runs about 221 days, ranking 12,505 of 40,283 US ZIP codes measured here, longest to shortest. Within AZ, it ranks 350 of 506.
Learn more
Two guides worth reading on 86343: local microclimates, on what one yard in Dewey-Humboldt can differ from the 86343 normal, and zone vs. frost date, on why Zone 8a and Dewey-Humboldt's frost date answer different questions.