Last Frost Day

Frost history / Spearfish, SD

Spearfish, SD: frost dates by year

Last spring and first fall frost at NOAA station USC00397882, 1951 to 2025, measured from daily minimum temperatures.

Elevation 3,633 ft, 44.498, -103.872. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 10Oct 2
EarliestApr 11 (2012)Sep 4 (1962)
LatestJun 13 (1969)Oct 27 (2010)
Trend1.3 days earlier per decade1.9 days later per decade
Years with data5961

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

Mar 31Apr 15Apr 30May 15May 30Jun 14Jun 2919601970198019902000201020201951: Jun 41953: May 221954: Jun 21955: Apr 161956: May 31959: Apr 261960: May 111963: May 221964: Jun 21966: May 131967: May 121968: May 201969: Jun 131970: May 141971: May 191972: May 41973: May 141974: May 151975: May 11976: May 71977: Apr 211978: May 81979: May 101980: May 81981: May 191982: May 61984: May 281986: May 11989: May 21990: May 101991: May 51993: Apr 201994: Apr 301995: May 11996: May 101997: May 21998: May 72004: May 142005: May 122006: May 92007: Apr 172008: May 262009: May 132010: May 122011: Apr 302012: Apr 112013: May 22014: May 82015: May 112016: May 142017: Apr 292018: Apr 242019: May 232020: May 122021: May 102022: May 232023: May 12024: May 52025: May 19

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 241952: Oct 21953: Oct 61954: Sep 211955: Sep 231958: Sep 301959: Sep 161960: Sep 221962: Sep 41963: Oct 271964: Sep 271965: Sep 161966: Oct 11967: Sep 271968: Oct 31969: Oct 51970: Sep 131971: Sep 181972: Sep 261973: Sep 151974: Sep 301975: Oct 91976: Sep 271977: Oct 21978: Sep 201979: Oct 131980: Oct 111981: Oct 61982: Oct 61983: Sep 201985: Sep 221989: Sep 111990: Oct 61992: Oct 61993: Sep 121994: Oct 231995: Sep 191996: Oct 161997: Oct 122001: Oct 52003: Oct 252004: Oct 12005: Oct 52006: Sep 192007: Sep 142008: Oct 112009: Oct 62010: Oct 272011: Oct 202012: Oct 42013: Oct 102014: Sep 112015: Oct 162016: Oct 62019: Oct 12020: Sep 82021: Oct 132022: Oct 182023: Oct 62024: Oct 152025: Oct 12

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

"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.