Williams, AZ 86018 Frost Dates
When can you plant in Williams, AZ?
Typically, the last spring freeze lands around 06/21, roughly 297 days out. The first fall frost typically arrives around 09/17, about 85 frost-free days later.
Williams sits in USDA Zone 6b (-5 to 0°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.
What to do before the first frost
About 3 weeks of growing season left in Williams before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 06/21 isn't a guarantee
06/21 is the middle of 30 years of NOAA records, not a promise. Plant by 06/09 and you're betting against frost in roughly 9 years out of 10. 07/04 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Williams compares
Williams's growing season runs about 85 days, ranking 39,983 of 40,283 US ZIP codes measured here, longest to shortest. Within AZ, it ranks 506 of 506.
Learn more
the frost range covers how to read the range around Williams's dates instead of trusting one. local microclimates covers what one yard in Williams can differ from the 86018 normal.