Last Frost Day

Frost history / Flagstaff Pulliam Ap, AZ

Flagstaff Pulliam Ap, AZ: frost dates by year

Last spring and first fall frost at NOAA station USW00003103, 1951 to 2024, measured from daily minimum temperatures.

Elevation 7,003 ft, 35.144, -111.666. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianJun 10Sep 23
EarliestApr 30 (2009)Aug 22 (1968)
LatestJul 8 (1955)Oct 18 (2024)
Trend1.8 days earlier per decade1.3 days later per decade
Years with data7374

At 28°F (hard freeze) the median last spring date is May 26 and the median first fall date is Oct 8.

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)

Apr 15Apr 30May 15May 30Jun 14Jun 29Jul 1419601970198019902000201020201951: Jun 121952: Jun 211953: Jun 41954: Jun 111955: Jul 81956: Jun 161957: May 261958: Jun 141959: Jun 11960: May 261961: Jun 11962: Jun 171963: Jun 251964: Jun 201965: Jun 281966: Jun 101967: Jun 151968: Jun 101969: Jun 111970: Jun 151971: Jun 121972: May 271973: Jun 161974: Jun 91975: Jun 261976: Jun 251977: May 271978: Jun 61979: Jun 201980: Jun 151981: May 211982: Jun 91983: Jun 131984: Jun 91985: Jun 41986: May 191987: May 301988: Jun 111989: Jun 11990: Jun 171991: Jun 271992: May 251993: Jun 91995: Jun 211996: Jun 11997: Jun 161998: Jun 181999: Jun 112000: Jun 112001: Jun 152002: May 252003: May 122004: Jun 112005: Jun 292006: May 312007: Jun 82008: Jun 132009: Apr 302010: May 302011: Jun 202012: May 292013: May 242014: May 242015: Jun 42016: May 312017: May 212018: May 272019: Jun 12020: Jun 102021: May 252022: Jun 202023: Jun 242024: May 22

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201951: Sep 131952: Sep 121953: Sep 231954: Sep 211955: Sep 211956: Oct 41957: Sep 191958: Sep 141959: Sep 251960: Sep 231961: Sep 41962: Oct 21963: Sep 211964: Sep 201965: Sep 191966: Oct 81967: Oct 71968: Aug 221969: Oct 11970: Sep 151971: Sep 161972: Sep 201973: Sep 241974: Sep 161975: Sep 241976: Oct 41977: Sep 181978: Sep 191979: Sep 211980: Sep 221981: Oct 141982: Sep 281983: Oct 41984: Sep 291985: Sep 121986: Sep 111987: Sep 141988: Sep 131989: Sep 151990: Sep 291991: Oct 51992: Oct 51993: Sep 141994: Sep 151995: Sep 301996: Sep 201997: Sep 221998: Sep 271999: Sep 42000: Sep 252001: Sep 92002: Oct 32003: Oct 42004: Sep 52005: Sep 152006: Sep 172007: Sep 182008: Oct 62009: Oct 12010: Oct 82011: Oct 72012: Oct 72013: Sep 232014: Sep 292015: Oct 32016: Sep 152017: Sep 232018: Oct 72019: Sep 222020: Sep 102021: Sep 302022: Oct 132023: Oct 32024: Oct 18

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
2024May 22Oct 18May 10Oct 30
2023Jun 24Oct 3Apr 27Oct 13
2022Jun 20Oct 13May 31Oct 24
2021May 25Sep 30May 24Oct 10
2020Jun 10Sep 10May 21Sep 10
2019Jun 1Sep 22May 28Oct 11
2018May 27Oct 7May 4Oct 16
2017May 21Sep 23May 20Sep 24
2016May 31Sep 15May 2Oct 7
2015Jun 4Oct 3May 20Nov 1
2014May 24Sep 29May 24Oct 30
2013May 24Sep 23May 10Sep 28
2012May 29Oct 7May 28Oct 18
2011Jun 20Oct 7Jun 7Oct 7
2010May 30Oct 8May 25Oct 27
2009Apr 30Oct 1Apr 30Oct 1
2008Jun 13Oct 6May 27Oct 6
2007Jun 8Sep 18May 9Sep 30
2006May 31Sep 17May 29Sep 18
2005Jun 29Sep 15May 13Oct 6
2004Jun 11Sep 5May 14Sep 22
2003May 12Oct 4May 12Oct 25
2002May 25Oct 3May 24Oct 4
2001Jun 15Sep 9Jun 15Oct 10
2000Jun 11Sep 25May 19Oct 12
1999Jun 11Sep 4Jun 5Oct 9
1998Jun 18Sep 27Jun 18Oct 1
1997Jun 16Sep 22Jun 15Oct 8
1996Jun 1Sep 20May 25Oct 18
1995Jun 21Sep 30Jun 18Oct 2
1994no dataSep 15no dataOct 6
1993Jun 9Sep 14Jun 7Oct 19
1992May 25Oct 5Apr 23Oct 8
1991Jun 27Oct 5Jun 2Oct 26
1990Jun 17Sep 29May 20Oct 9
1989Jun 1Sep 15May 31Oct 16
1988Jun 11Sep 13May 31Sep 23
1987May 30Sep 14May 29Oct 16
1986May 19Sep 11May 18Oct 4
1985Jun 4Sep 12May 15Sep 12
1984Jun 9Sep 29May 8Oct 14
1983Jun 13Oct 4Jun 3Oct 20
1982Jun 9Sep 28May 16Oct 1
1981May 21Oct 14May 21Oct 14
1980Jun 15Sep 22Jun 2Oct 16
1979Jun 20Sep 21Jun 19Oct 18
1978Jun 6Sep 19May 26Sep 19
1977May 27Sep 18May 20Oct 14
1976Jun 25Oct 4Jun 12Oct 5
1975Jun 26Sep 24Jun 26Oct 1
1974Jun 9Sep 16Jun 9Sep 28
1973Jun 16Sep 24May 3Oct 10
1972May 27Sep 20May 26Oct 22
1971Jun 12Sep 16Jun 6Sep 16
1970Jun 15Sep 15May 8Sep 23
1969Jun 11Oct 1May 3Oct 3
1968Jun 10Aug 22Jun 10Aug 23
1967Jun 15Oct 7May 16Oct 8
1966Jun 10Oct 8May 11Oct 13
1965Jun 28Sep 19Jun 27Sep 21
1964Jun 20Sep 20Jun 11Oct 21
1963Jun 25Sep 21Jun 11Oct 13
1962Jun 17Oct 2May 26Oct 6
1961Jun 1Sep 4Jun 1Sep 4
1960May 26Sep 23May 26Oct 13
1959Jun 1Sep 25May 26Sep 25
1958Jun 14Sep 14May 14Oct 21
1957May 26Sep 19May 24Oct 8
1956Jun 16Oct 4May 21Oct 9
1955Jul 8Sep 21Jun 3Sep 21
1954Jun 11Sep 21Jun 11Oct 16
1953Jun 4Sep 23Jun 2Sep 29
1952Jun 21Sep 12May 17Sep 13
1951Jun 12Sep 13Jun 3Oct 4

"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.