Last Frost Day

Frost history / Chadron 3SW, NE

Chadron 3SW, NE: frost dates by year

Last spring and first fall frost at NOAA station USC00251575, 1951 to 2025, measured from daily minimum temperatures.

Elevation 3,383 ft, 42.808, -103.053. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 14Sep 23
EarliestApr 15 (1986)Aug 23 (2015)
LatestJun 19 (2024)Oct 26 (1963)
Trend0.8 days later per decade0.5 days earlier per decade
Years with data6662

At 28°F (hard freeze) the median last spring date is May 2 and the median first fall date is Oct 4.

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: May 111953: May 151954: May 81955: May 51956: May 141957: Apr 281958: May 11959: May 231960: May 201961: May 151962: May 21964: May 241965: May 91966: May 241967: May 141968: May 201969: Jun 141970: May 21971: May 71972: May 41973: May 221974: May 311975: May 261976: May 171977: Apr 251978: May 131979: May 111980: May 131981: May 141982: May 71985: May 61986: Apr 151989: May 261990: May 171991: May 61994: Apr 301995: May 171996: May 111997: May 191998: Apr 211999: May 82000: May 132001: May 72002: May 242003: May 202006: May 142007: Jun 82008: May 142009: May 162010: May 142011: May 72012: May 202013: May 62014: May 152015: May 302016: May 182017: May 302018: May 22019: Jun 102020: May 172021: May 132022: May 252023: May 22024: Jun 192025: May 17

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 211952: Sep 151953: Sep 211954: Sep 211955: Sep 251956: Sep 231957: Oct 81958: Sep 211959: Sep 291960: Sep 301961: Sep 131962: Sep 91963: Oct 261964: Sep 201965: Sep 161966: Sep 301967: Sep 261968: Oct 31969: Oct 51970: Sep 131971: Sep 191972: Sep 211973: Sep 171974: Sep 281975: Sep 211976: Sep 91977: Oct 101978: Sep 211979: Oct 41980: Oct 101981: Sep 271984: Sep 241985: Sep 201992: Oct 81994: Oct 231995: Sep 201996: Sep 271997: Oct 121998: Oct 121999: Oct 22000: Sep 232001: Oct 62002: Oct 132003: Sep 302006: Sep 192009: Sep 282010: Sep 32011: Sep 212012: Sep 142013: Sep 202014: Sep 122015: Aug 232016: Sep 102017: Sep 52018: Sep 262019: Oct 32020: Sep 82021: Oct 32022: Oct 82023: Oct 62024: Sep 222025: Sep 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 17Sep 6Apr 23Sep 6
2024Jun 19Sep 22May 4Oct 1
2023May 2Oct 6May 2Oct 6
2022May 25Oct 8May 22Oct 8
2021May 13Oct 3May 4Oct 11
2020May 17Sep 8May 10Sep 10
2019Jun 10Oct 3May 12Oct 3
2018May 2Sep 26Apr 25Sep 26
2017May 30Sep 5May 4Sep 27
2016May 18Sep 10May 17Oct 6
2015May 30Aug 23May 21Oct 16
2014May 15Sep 12May 15Oct 4
2013May 6Sep 20May 6Oct 7
2012May 20Sep 14May 12Oct 6
2011May 7Sep 21May 2Sep 22
2010May 14Sep 3May 14Oct 13
2009May 16Sep 28May 16Sep 28
2008May 14no dataMay 11no data
2007Jun 8no dataMay 24no data
2006May 14Sep 19May 3Sep 19
2003May 20Sep 30Apr 8Oct 26
2002May 24Oct 13May 9Oct 13
2001May 7Oct 6Apr 24Oct 16
2000May 13Sep 23Apr 22Oct 5
1999May 8Oct 2Apr 18Oct 17
1998Apr 21Oct 12Apr 20Nov 4
1997May 19Oct 12Apr 16Oct 25
1996May 11Sep 27Apr 30Oct 18
1995May 17Sep 20Apr 26Sep 21
1994Apr 30Oct 23Apr 30Nov 3
1992no dataOct 8no dataOct 8
1991May 6no dataMay 6no data
1990May 17no dataMay 10no data
1989May 26no dataMay 6no data
1986Apr 15no dataApr 15no data
1985May 6Sep 20May 6Sep 24
1984no dataSep 24no dataSep 25
1982May 7no dataMay 6no data
1981May 14Sep 27Apr 14Oct 6
1980May 13Oct 10Apr 25Oct 10
1979May 11Oct 4May 11Oct 28
1978May 13Sep 21Apr 20Oct 6
1977Apr 25Oct 10Apr 7Oct 11
1976May 17Sep 9May 3Sep 28
1975May 26Sep 21Apr 20Oct 1
1974May 31Sep 28Apr 16Sep 30
1973May 22Sep 17May 14Sep 17
1972May 4Sep 21Apr 24Sep 26
1971May 7Sep 19Apr 28Oct 8
1970May 2Sep 13Apr 30Sep 26
1969Jun 14Oct 5Jun 2Oct 11
1968May 20Oct 3May 11Oct 6
1967May 14Sep 26May 4Sep 27
1966May 24Sep 30May 19Oct 1
1965May 9Sep 16Apr 11Sep 17
1964May 24Sep 20Apr 17Sep 27
1963no dataOct 26no dataOct 27
1962May 2Sep 9May 1Sep 10
1961May 15Sep 13Apr 28Sep 14
1960May 20Sep 30Apr 30Sep 30
1959May 23Sep 29Apr 22Sep 30
1958May 1Sep 21May 1Sep 27
1957Apr 28Oct 8Apr 13Oct 24
1956May 14Sep 23Apr 29Oct 26
1955May 5Sep 25Apr 24Oct 14
1954May 8Sep 21May 4Sep 21
1953May 15Sep 21May 13Oct 4
1952May 11Sep 15Apr 14Sep 22
1951Jun 3Sep 21May 6Sep 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.