When is the last frost in Apache Junction, AZ?

For ZIP code 85178, the average last spring frost (32°F) is February 1, based on NOAA 1991-2020 climate normals for the E Mesa, AZ weather station. There is a 1-in-10 chance of a frost after February 28.

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 22, so tender plants are at risk from that point on.

How long is the growing season in 85178?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 312 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 85178Apache Junction, AZ

The average last spring frost in Apache Junction is February 1 and the average first fall frost is December 10, giving a typical growing season of about 312 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Feb 1
Average first fall frost: Dec 10
Growing season: 312 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)	Jan 31 · Feb 27 · Mar 15	Nov 13 · Nov 30 · Dec 15	276 days	100%
Frost / freeze (32°F)	Jan 1 · Feb 1 · Feb 28	Nov 22 · Dec 10 · Jan 1	312 days	98%
Hard freeze (28°F)	Dec 13 · Jan 11 · Feb 11	Dec 1 · Dec 26 · Jan 28	352 days	70%

Where these dates come from

ZIP code 85178 is matched to the NOAA station E Mesa, AZ, 9.2 km away, at 1,518 ft elevation (178 ft lower than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
E Mesa, AZ (used)	1,518 ft	Feb 1	Dec 10
Apache Junction 5 Ne, AZ	2,070 ft	Feb 11	Dec 10
Stewart Mtn Dam, AZ	1,422 ft	Feb 13	Dec 5
Mormon Flat, AZ	1,705 ft	Jan 29	Dec 24

Frost dates near Apache Junction

Apache Junction, AZ 85120 · last Feb 1, first Dec 10
Mesa, AZ 85209 · last Feb 1, first Dec 10
Higley, AZ 85236 · last Feb 1, first Dec 10
Queen Creek, AZ 85142 · last Feb 1, first Dec 11
Gilbert, AZ 85296 · last Feb 1, first Dec 10
Tortilla Flat, AZ 85190 · last Feb 11, first Dec 10
Gold Canyon, AZ 85118 · last Feb 11, first Dec 10
San Tan Valley, AZ 85140 · last Feb 17, first Nov 29

Frequently asked questions

When is the last frost in Apache Junction, AZ?: For ZIP code 85178, the average last spring frost (32°F) is February 1, based on NOAA 1991-2020 climate normals for the E Mesa, AZ weather station. There is a 1-in-10 chance of a frost after February 28.
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 22, so tender plants are at risk from that point on.
How long is the growing season in 85178?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 312 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.