When is the last frost in Apache Junction, AZ?

For ZIP code 85117, the average last spring frost (32°F) is February 11, based on NOAA 1991-2020 climate normals for the Apache Junction 5 Ne, AZ weather station. There is a 1-in-10 chance of a frost after March 7.

When is the first frost in Apache Junction, AZ?

The average first fall frost (32°F) is December 10. There is a 1-in-10 chance of frost by November 19, so tender plants are at risk from that point on.

How long is the growing season in 85117?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 304 days long.

Are these frost dates a forecast?

No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.

Frost dates for 85117Apache Junction, AZ

The average last spring frost in Apache Junction is February 11 and the average first fall frost is December 10, giving a typical growing season of about 304 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Feb 11
Average first fall frost: Dec 10
Growing season: 304 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
Temperature	Last spring: 90% / 50% / 10% chance	First fall: 10% / 50% / 90% chance	Growing season (50%)	Years with at least one
Light frost (36°F)	Feb 7 · Mar 6 · Apr 1	Nov 7 · Nov 28 · Dec 15	266 days	100%
Frost / freeze (32°F)	Jan 5 · Feb 11 · Mar 7	Nov 19 · Dec 10 · Jan 1	304 days	99%
Hard freeze (28°F)	Dec 12 · Jan 13 · Feb 18	Nov 28 · Dec 22 · Feb 1	344 days	78%

Where these dates come from

ZIP code 85117 is matched to the NOAA station Apache Junction 5 Ne, AZ, 20.7 km away, at 2,070 ft elevation (141 ft lower than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Apache Junction 5 Ne, AZ (used)	2,070 ft	Feb 11	Dec 10
Superior, AZ	2,860 ft	Jan 18	Dec 28
Mormon Flat, AZ	1,705 ft	Jan 29	Dec 24
E Mesa, AZ	1,518 ft	Feb 1	Dec 10

Frost dates near Apache Junction

Gold Canyon, AZ 85118 · last Feb 11, first Dec 10
Apache Junction, AZ 85119 · last Feb 11, first Dec 10
Superior, AZ 85173 · last Jan 18, first Dec 28
Tortilla Flat, AZ 85190 · last Feb 11, first Dec 10
San Tan Valley, AZ 85140 · last Feb 17, first Nov 29
Mesa, AZ 85212 · last Feb 1, first Dec 10
Queen Creek, AZ 85142 · last Feb 1, first Dec 11
Higley, AZ 85236 · last Feb 1, first Dec 10

Frequently asked questions

When is the last frost in Apache Junction, AZ?: For ZIP code 85117, the average last spring frost (32°F) is February 11, based on NOAA 1991-2020 climate normals for the Apache Junction 5 Ne, AZ weather station. There is a 1-in-10 chance of a frost after March 7.
When is the first frost in Apache Junction, AZ?: The average first fall frost (32°F) is December 10. There is a 1-in-10 chance of frost by November 19, so tender plants are at risk from that point on.
How long is the growing season in 85117?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 304 days long.
Are these frost dates a forecast?: No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.