Last Frost Day

Frost history / Tucson Intl Ap, AZ

Tucson Intl Ap, AZ: frost dates by year

Last spring and first fall frost at NOAA station USW00023160, 1951 to 2024, measured from daily minimum temperatures.

Elevation 2,549 ft, 32.131, -110.955. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianFeb 27Nov 29
EarliestJan 4 (1993)Oct 27 (2020)
LatestApr 5 (2023)Dec 29 (2018)
Trend3.9 days earlier per decade1.4 days later per decade
Years with data74, 2 with no freeze74, 3 with no freeze

At 28°F (hard freeze) the median last spring date is Feb 3 and the median first fall date is Dec 13.

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)

Dec 16Dec 31Jan 15Jan 30Feb 14Mar 1Mar 16Mar 31Apr 1519601970198019902000201020201951: Mar 191952: Mar 231953: Feb 251954: Mar 131955: Mar 221956: Mar 161957: Jan 221958: Feb 281959: Mar 161960: Mar 171961: Feb 51962: Mar 241963: Mar 51964: Mar 91965: Mar 41966: Mar 51967: Mar 71968: Feb 11969: Mar 161970: Feb 31971: Mar 61972: Feb 81973: Jan 281974: Mar 101975: Mar 291976: Mar 41977: Feb 271978: Feb 201979: Feb 71981: Feb 21982: Mar 61983: Jan 221984: Feb 271985: Mar 41986: Feb 111987: Feb 281988: Mar 131989: Mar 51990: Mar 151991: Jan 311992: Jan 171993: Jan 41994: Feb 11995: Mar 261996: Jan 251997: Feb 221998: Mar 11999: Feb 112000: Jan 92001: Feb 162002: Mar 32003: Feb 102004: Feb 142005: Jan 132006: Mar 132007: Mar 32008: Feb 72009: Feb 142011: Feb 282012: Mar 32013: Feb 282014: Jan 62015: Jan 42016: Feb 52017: Jan 292018: Jan 232019: Feb 242020: Feb 62021: Mar 12022: Feb 182023: Apr 52024: Jan 12

First fall frost (32°F)

Oct 12Oct 27Nov 11Nov 26Dec 11Dec 26Jan 1019601970198019902000201020201951: Dec 81952: Nov 261953: Nov 191954: Dec 171955: Nov 161956: Nov 31957: Nov 231958: Nov 161959: Dec 151960: Nov 281961: Nov 221962: Nov 191963: Dec 131964: Nov 171965: Dec 201966: Nov 271967: Dec 21968: Dec 31969: Dec 61970: Dec 111971: Oct 301972: Nov 11973: Nov 241974: Dec 101975: Nov 291976: Nov 281978: Dec 31979: Nov 201980: Nov 271981: Dec 231982: Dec 31983: Nov 271984: Nov 261985: Nov 151986: Dec 11987: Nov 261988: Nov 191989: Nov 281990: Nov 281991: Dec 21992: Nov 211993: Nov 261994: Nov 201995: Dec 231996: Nov 301997: Dec 111998: Dec 71999: Nov 232000: Nov 182001: Nov 272002: Dec 192003: Nov 232004: Nov 302005: Nov 282006: Nov 302007: Dec 152008: Dec 212009: Dec 42010: Nov 262011: Dec 52012: Dec 112013: Dec 102014: Dec 242015: Nov 292016: Nov 302017: Dec 222018: Dec 292019: Oct 312020: Oct 272021: Dec 182022: Dec 14

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

Year by year

YearLast spring 32°FFirst fall 32°FLast spring 28°FFirst fall 28°F
2024Jan 12nonenonenone
2023Apr 5noneJan 26none
2022Feb 18Dec 14Feb 3none
2021Mar 1Dec 18nonenone
2020Feb 6Oct 27Feb 6none
2019Feb 24Oct 31Jan 3none
2018Jan 23Dec 29noneDec 29
2017Jan 29Dec 22nonenone
2016Feb 5Nov 30nonenone
2015Jan 4Nov 29noneDec 27
2014Jan 6Dec 24nonenone
2013Feb 28Dec 10Jan 16none
2012Mar 3Dec 11nonenone
2011Feb 28Dec 5Feb 4Dec 6
2010noneNov 26noneNov 30
2009Feb 14Dec 4noneDec 26
2008Feb 7Dec 21Jan 18Dec 27
2007Mar 3Dec 15Jan 22Dec 22
2006Mar 13Nov 30Jan 20Nov 30
2005Jan 13Nov 28noneNov 28
2004Feb 14Nov 30noneNov 30
2003Feb 10Nov 23noneDec 28
2002Mar 3Dec 19Mar 3none
2001Feb 16Nov 27noneDec 13
2000Jan 9Nov 18Jan 3none
1999Feb 11Nov 23Feb 11Dec 4
1998Mar 1Dec 7noneDec 8
1997Feb 22Dec 11Feb 7Dec 13
1996Jan 25Nov 30Jan 3Dec 18
1995Mar 26Dec 23nonenone
1994Feb 1Nov 20Feb 1Nov 20
1993Jan 4Nov 26nonenone
1992Jan 17Nov 21Jan 15Nov 25
1991Jan 31Dec 2Jan 30none
1990Mar 15Nov 28Feb 16Dec 22
1989Mar 5Nov 28Jan 12Dec 12
1988Mar 13Nov 19Jan 21Dec 27
1987Feb 28Nov 26Jan 21Dec 15
1986Feb 11Dec 1nonenone
1985Mar 4Nov 15Feb 2Dec 13
1984Feb 27Nov 26Feb 18Nov 27
1983Jan 22Nov 27nonenone
1982Mar 6Dec 3noneDec 25
1981Feb 2Dec 23noneDec 24
1980noneNov 27nonenone
1979Feb 7Nov 20Jan 30Nov 21
1978Feb 20Dec 3noneDec 7
1977Feb 27noneFeb 27none
1976Mar 4Nov 28Jan 5Dec 25
1975Mar 29Nov 29Feb 23Dec 15
1974Mar 10Dec 10Feb 8Dec 23
1973Jan 28Nov 24Jan 21Dec 25
1972Feb 8Nov 1Jan 31Dec 12
1971Mar 6Oct 30Mar 3Oct 30
1970Feb 3Dec 11Feb 3none
1969Mar 16Dec 6Mar 15Dec 31
1968Feb 1Dec 3noneDec 18
1967Mar 7Dec 2Jan 8Dec 10
1966Mar 5Nov 27Mar 4Dec 11
1965Mar 4Dec 20Mar 4none
1964Mar 9Nov 17Feb 22none
1963Mar 5Dec 13Jan 21Dec 14
1962Mar 24Nov 19Mar 14none
1961Feb 5Nov 22nonenone
1960Mar 17Nov 28Feb 25Nov 28
1959Mar 16Dec 15Mar 6Dec 27
1958Feb 28Nov 16Jan 23Nov 17
1957Jan 22Nov 23noneDec 3
1956Mar 16Nov 3Mar 13Nov 3
1955Mar 22Nov 16Mar 22none
1954Mar 13Dec 17noneDec 17
1953Feb 25Nov 19Feb 21Nov 22
1952Mar 23Nov 26Feb 16Dec 24
1951Mar 19Dec 8Mar 4Dec 21

"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.