When is the last frost in Tucson, AZ?

For ZIP code 85747, the average last spring frost (32°F) is January 26, based on NOAA 1991-2020 climate normals for the Saguaro Np, AZ weather station. There is a 1-in-10 chance of a frost after February 25.

When is the first frost in Tucson, AZ?

The average first fall frost (32°F) is December 16. There is a 1-in-10 chance of frost by November 26, so tender plants are at risk from that point on.

How long is the growing season in 85747?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 326 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 85747Tucson, AZ

The average last spring frost in Tucson is January 26 and the average first fall frost is December 16, giving a typical growing season of about 326 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Jan 26
Average first fall frost: Dec 16
Growing season: 326 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 22 · Feb 22 · Mar 18	Nov 16 · Dec 2 · Dec 18	282 days	100%
Frost / freeze (32°F)	Dec 24 · Jan 26 · Feb 25	Nov 26 · Dec 16 · Jan 17	326 days	93%
Hard freeze (28°F)	Dec 14 · Jan 7 · Feb 9	Dec 9 · Dec 28 · Feb 3	363 days	55%

Where these dates come from

ZIP code 85747 is matched to the NOAA station Saguaro Np, AZ, 9 km away, at 3,080 ft elevation (101 ft higher than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Saguaro Np, AZ (used)	3,080 ft	Jan 26	Dec 16
Tucson Intl Ap, AZ	2,549 ft	Feb 5	Dec 9
Tucson Wfo, AZ	2,435 ft	Jan 20	Dec 17
Tucson Camp Ave Exp, AZ	2,330 ft	Feb 20	Nov 27

Frost dates near Tucson

Vail, AZ 85641 · last Jan 26, first Dec 16
Tucson, AZ 85730 · last Feb 5, first Dec 9
Sahuarita, AZ 85629 · last Feb 25, first Nov 27
Mount Lemmon, AZ 85619 · last Mar 23, first Nov 22
Green Valley, AZ 85614 · last Feb 25, first Nov 27
Benson, AZ 85602 · last Apr 12, first Nov 1
Pomerene, AZ 85627 · last Apr 12, first Nov 1
Sonoita, AZ 85637 · last Apr 18, first Nov 1

Frequently asked questions

When is the last frost in Tucson, AZ?: For ZIP code 85747, the average last spring frost (32°F) is January 26, based on NOAA 1991-2020 climate normals for the Saguaro Np, AZ weather station. There is a 1-in-10 chance of a frost after February 25.
When is the first frost in Tucson, AZ?: The average first fall frost (32°F) is December 16. There is a 1-in-10 chance of frost by November 26, so tender plants are at risk from that point on.
How long is the growing season in 85747?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 326 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.