Last Frost Day

Frost history / Altamont, UT

Altamont, UT: frost dates by year

Last spring and first fall frost at NOAA station USC00420074, 1953 to 2025, measured from daily minimum temperatures.

Elevation 6,456 ft, 40.367, -110.299. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 30Sep 22
EarliestMay 4 (2013)Aug 17 (1960)
LatestJun 30 (2020)Oct 28 (2015)
Trendlittle change (less than half a day per decade)1.1 days later per decade
Years with data6767

At 28°F (hard freeze) the median last spring date is May 14 and the median first fall date is Oct 1.

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 1419601970198019902000201020201954: Jun 71955: Jun 31956: May 151957: May 221958: May 131959: May 211960: Jun 211961: May 171962: Jun 81963: May 131964: May 101967: May 151968: Jun 301969: May 91970: May 311972: May 301973: Jun 201974: Jun 91975: Jun 251976: Jun 151977: May 211978: Jun 11979: Jun 91980: May 271981: Jun 151982: Jun 91983: May 221984: Jun 111985: Jun 261986: May 231987: May 301988: May 311989: Jun 211990: Jun 21991: May 191992: Jun 11993: Jun 251994: May 211995: Jun 101996: May 211997: May 271998: Jun 181999: Jun 52002: Jun 102003: May 202004: May 262005: Jun 82006: May 302007: Jun 82008: Jun 92009: May 102010: May 302011: Jun 102012: May 282013: May 42014: May 152015: May 172016: May 232017: May 222018: May 132019: Jun 232020: Jun 302021: Jun 122022: Jun 152023: May 112024: May 262025: May 20

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201953: Sep 31954: Sep 301955: Sep 271956: Sep 221957: Sep 141958: Sep 261959: Sep 231960: Aug 171961: Sep 31962: Sep 91963: Oct 141966: Oct 41967: Sep 131968: Sep 151969: Oct 31970: Sep 151971: Sep 171972: Oct 211973: Sep 21974: Sep 121975: Sep 191976: Oct 41977: Sep 191978: Sep 121979: Oct 91980: Sep 221981: Sep 261982: Sep 141983: Sep 201984: Sep 151985: Sep 231986: Sep 261987: Oct 161988: Sep 121989: Sep 131990: Oct 81991: Sep 151992: Aug 261993: Sep 141995: Sep 221996: Sep 181997: Oct 91998: Oct 42001: Sep 82002: Oct 42003: Sep 182004: Sep 152005: Oct 52006: Sep 172007: Sep 252008: Oct 112009: Sep 222010: Oct 262011: Oct 72012: Oct 42013: Sep 282014: Sep 122015: Oct 282017: Sep 242018: Sep 252019: Sep 212020: Sep 12021: Sep 202022: Oct 122023: Sep 62024: Aug 292025: Oct 6

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
2025May 20Oct 6May 20Oct 18
2024May 26Aug 29May 24Oct 31
2023May 11Sep 6May 8Oct 14
2022Jun 15Oct 12May 31Oct 14
2021Jun 12Sep 20May 22Sep 21
2020Jun 30Sep 1Jun 30Sep 9
2019Jun 23Sep 21May 3Sep 21
2018May 13Sep 25Apr 26Sep 25
2017May 22Sep 24May 20Sep 25
2016May 23no dataMay 11no data
2015May 17Oct 28May 11Oct 28
2014May 15Sep 12May 14Oct 13
2013May 4Sep 28May 3Sep 28
2012May 28Oct 4May 6Oct 4
2011Jun 10Oct 7May 5Oct 27
2010May 30Oct 26May 25Oct 26
2009May 10Sep 22May 10Oct 1
2008Jun 9Oct 11May 14Oct 12
2007Jun 8Sep 25May 23Sep 25
2006May 30Sep 17May 29Sep 17
2005Jun 8Oct 5Apr 30Oct 5
2004May 26Sep 15May 12Sep 22
2003May 20Sep 18May 6Sep 18
2002Jun 10Oct 4May 10Oct 12
2001no dataSep 8no dataOct 5
1999Jun 5no dataMay 18no data
1998Jun 18Oct 4Apr 20Oct 4
1997May 27Oct 9May 4Oct 12
1996May 21Sep 18May 21Sep 20
1995Jun 10Sep 22May 14Sep 23
1994May 21no dataApr 30no data
1993Jun 25Sep 14May 9Oct 10
1992Jun 1Aug 26May 10Aug 26
1991May 19Sep 15May 12Sep 15
1990Jun 2Oct 8Jun 2Oct 8
1989Jun 21Sep 13May 26Oct 18
1988May 31Sep 12May 31Sep 19
1987May 30Oct 16May 4Oct 16
1986May 23Sep 26May 23Oct 1
1985Jun 26Sep 23May 14Sep 23
1984Jun 11Sep 15Jun 9Sep 25
1983May 22Sep 20May 15Sep 20
1982Jun 9Sep 14Apr 23Oct 2
1981Jun 15Sep 26May 14Oct 14
1980May 27Sep 22May 26Oct 15
1979Jun 9Oct 9Jun 9Oct 21
1978Jun 1Sep 12May 31Sep 19
1977May 21Sep 19May 21Oct 1
1976Jun 15Oct 4Jun 14Oct 7
1975Jun 25Sep 19May 7Oct 9
1974Jun 9Sep 12May 21Sep 13
1973Jun 20Sep 2Jun 19Sep 26
1972May 30Oct 21May 30Oct 24
1971no dataSep 17no dataSep 18
1970May 31Sep 15May 16Sep 23
1969May 9Oct 3May 8Oct 3
1968Jun 30Sep 15Jun 30Sep 21
1967May 15Sep 13May 15Sep 13
1966no dataOct 4no dataOct 14
1964May 10no dataMay 9no data
1963May 13Oct 14May 13Nov 1
1962Jun 8Sep 9May 16Sep 9
1961May 17Sep 3May 14Sep 24
1960Jun 21Aug 17May 24Oct 11
1959May 21Sep 23May 21Sep 23
1958May 13Sep 26Apr 29Sep 26
1957May 22Sep 14Apr 28Sep 21
1956May 15Sep 22May 14Oct 13
1955Jun 3Sep 27May 28Oct 6
1954Jun 7Sep 30Jun 2Oct 14
1953no dataSep 3no dataSep 3

"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.