Tucson 11 W, AZ: frost dates by year

Last spring and first fall frost at NOAA station USW00053131, 2003 to 2024, measured from daily minimum temperatures.

Elevation 2,733 ft, 32.239, -111.170. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Feb 11	Dec 8
Earliest	Jan 4 (2015)	Nov 23 (2003)
Latest	Mar 20 (2012)	Dec 28 (2018)
Trend	2.8 days later per decade	9.0 days later per decade
Years with data	21, 1 with no freeze	22, 2 with no freeze

At 28°F (hard freeze) the median last spring date is Feb 3 and the median first fall date is Dec 22.

The trend is a straight-line fit through the years with a freeze. A positive spring trend means the last frost now comes later. Short or patchy records give noisy trends.

Chart

Last spring frost (32°F)

First fall frost (32°F)

Dots are single years. The gray line is the median, the green line the fitted trend.

Year by year

Year	Last spring 32°F	First fall 32°F	Last spring 28°F	First fall 28°F
2024	no data	none	no data	none
2023	Mar 2	none	Feb 16	none
2022	Mar 8	Dec 14	Feb 3	none
2021	Jan 10	Dec 18	none	none
2020	Feb 6	Dec 4	Feb 6	none
2019	Mar 14	Dec 17	Feb 20	Dec 29
2018	Feb 25	Dec 28	none	Dec 29
2017	Jan 28	Dec 22	Jan 28	Dec 22
2016	Feb 4	Dec 1	Feb 4	none
2015	Jan 4	Nov 29	Jan 3	Dec 16
2014	Feb 2	Dec 26	none	Dec 27
2013	Feb 26	Dec 6	Jan 16	none
2012	Mar 20	Dec 20	none	none
2011	Feb 28	Dec 5	Feb 5	Dec 6
2010	none	Nov 26	none	Nov 30
2009	Jan 28	Dec 10	none	Dec 25
2008	Feb 7	Dec 21	Jan 18	Dec 27
2007	Mar 1	Dec 15	Jan 22	Dec 22
2006	Mar 13	Nov 30	none	Nov 30
2005	Jan 6	Nov 27	none	Nov 28
2004	Feb 14	Nov 29	Feb 13	Nov 30
2003	Feb 6	Nov 23	none	Dec 28

"none" means the station recorded no freeze at that threshold in that half of the year. "no data" means more than 10% of the season's daily readings were missing. Years with no usable data are left out. See the methodology for the rules, and the ZIP lookup for 1991 to 2020 frost probabilities.