Last Frost Day

Frost history / Delta, UT

Delta, UT: frost dates by year

Last spring and first fall frost at NOAA station USW00023162, 1951 to 2024, measured from daily minimum temperatures.

Elevation 4,620 ft, 39.337, -112.586. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 20Sep 25
EarliestApr 15 (1952)Sep 2 (1973)
LatestJun 19 (1973)Oct 28 (1963)
Trend1.1 days later per decadelittle change (less than half a day per decade)
Years with data6468

At 28°F (hard freeze) the median last spring date is May 5 and the median first fall date is Oct 7.

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)

Mar 31Apr 15Apr 30May 15May 30Jun 14Jun 2919601970198019902000201020201951: Jun 31952: Apr 151953: May 131954: May 281955: May 161956: May 151957: Apr 261958: Apr 271959: May 201960: May 221961: May 51962: May 211963: Apr 291964: May 91965: May 111966: May 121967: May 151971: May 191972: May 211973: Jun 191974: May 211975: May 261976: Jun 151978: May 311979: Jun 91980: May 261981: Jun 151982: Jun 61983: May 201984: May 81985: May 141986: May 231987: May 31988: May 81989: May 201990: May 91991: May 191992: May 101993: May 91994: May 81995: May 131996: Apr 301997: May 261998: May 221999: May 172000: May 132001: Jun 142002: Jun 102003: May 212004: Jun 112005: Apr 302007: May 302008: May 132009: May 142010: May 142011: Jun 32012: Jun 102013: May 302018: Apr 212020: Jun 82021: May 242022: May 222023: May 72024: May 22

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 221952: Oct 151953: Oct 31954: Oct 141955: Sep 261956: Sep 221957: Sep 211958: Sep 251959: Sep 281960: Oct 151961: Sep 241962: Oct 141963: Oct 281964: Sep 201965: Sep 171966: Sep 151967: Oct 71970: Sep 151971: Sep 181972: Sep 301973: Sep 21974: Sep 121975: Oct 81976: Oct 41977: Sep 231978: Sep 181979: Oct 211980: Sep 221981: Oct 91982: Oct 21983: Sep 211984: Sep 251985: Sep 231986: Sep 211987: Sep 291988: Sep 121989: Oct 41990: Oct 31991: Oct 51992: Sep 261993: Sep 141994: Oct 191995: Sep 221996: Sep 191997: Oct 111998: Oct 41999: Sep 282000: Sep 242001: Sep 72002: Sep 192003: Sep 142004: Sep 42005: Sep 302006: Sep 172007: Sep 252008: Sep 232009: Sep 222010: Sep 112011: Oct 62012: Oct 42013: Sep 282014: Oct 132017: Sep 252018: Oct 92021: Sep 212022: Oct 142023: Oct 132024: Oct 19

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

"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.