Last Frost Day

Frost history / Rapid City Rgnl Ap, SD

Rapid City Rgnl Ap, SD: frost dates by year

Last spring and first fall frost at NOAA station USW00024090, 1951 to 2024, measured from daily minimum temperatures.

Elevation 3,160 ft, 44.043, -103.054. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 10Sep 28
EarliestApr 5 (1977)Sep 7 (2020)
LatestJun 14 (1969)Oct 27 (1963)
Trend1.1 days later per decadelittle change (less than half a day per decade)
Years with data7474

At 28°F (hard freeze) the median last spring date is Apr 30 and the median first fall date is Oct 10.

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 21952: Apr 141953: May 141954: May 41955: Apr 281956: May 31957: Apr 171958: Apr 301959: May 151960: May 61961: Apr 281962: Apr 171963: May 221964: Apr 191965: May 91966: May 191967: May 121968: May 201969: Jun 141970: May 21971: May 201972: May 71973: May 141974: May 231975: May 11976: May 61977: Apr 51978: Apr 231979: May 111980: May 81981: Apr 141982: May 61983: May 141984: May 281985: May 61986: May 11987: Apr 241988: May 41989: May 61990: May 101991: May 61992: May 261993: May 21994: May 11995: May 241996: May 101997: May 201998: Jun 31999: May 172000: May 132001: May 72002: May 242003: May 202004: May 142005: May 152006: May 102007: Apr 172008: May 112009: May 162010: May 142011: May 162012: May 122013: May 112014: May 152015: May 212016: May 152017: May 42018: Apr 282019: May 222020: May 102021: May 132022: May 242023: May 22024: May 4

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 261952: Oct 51953: Sep 211954: Sep 211955: Oct 221956: Oct 251957: Sep 191958: Sep 251959: Sep 291960: Oct 151961: Sep 251962: Sep 91963: Oct 271964: Sep 261965: Sep 151966: Sep 301967: Sep 271968: Oct 21969: Oct 51970: Sep 131971: Sep 161972: Sep 211973: Sep 171974: Sep 281975: Sep 211976: Sep 281977: Oct 91978: Oct 31979: Oct 101980: Oct 111981: Oct 61982: Oct 71983: Sep 191984: Sep 231985: Sep 191986: Oct 41987: Oct 21988: Sep 201989: Sep 101990: Oct 61991: Sep 171992: Sep 181993: Sep 131994: Oct 221995: Sep 201996: Sep 251997: Oct 91998: Oct 121999: Sep 132000: Sep 232001: Sep 92002: Sep 222003: Oct 12004: Oct 12005: Oct 52006: Sep 192007: Sep 142008: Sep 242009: Sep 282010: Oct 132011: Sep 222012: Sep 232013: Oct 42014: Sep 122015: Oct 152016: Oct 52017: Oct 32018: Oct 32019: Oct 32020: Sep 72021: Oct 122022: Oct 72023: Oct 62024: Oct 15

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 4Oct 15Apr 21Nov 4
2023May 2Oct 6May 1Oct 7
2022May 24Oct 7May 22Oct 18
2021May 13Oct 12Apr 22Oct 14
2020May 10Sep 7May 10Sep 9
2019May 22Oct 3May 10Oct 9
2018Apr 28Oct 3Apr 25Oct 3
2017May 4Oct 3Apr 29Oct 10
2016May 15Oct 5May 14Oct 7
2015May 21Oct 15Apr 23Oct 16
2014May 15Sep 12May 9Oct 28
2013May 11Oct 4May 4Oct 16
2012May 12Sep 23Apr 11Oct 6
2011May 16Sep 22May 3Oct 19
2010May 14Oct 13May 8Oct 27
2009May 16Sep 28May 16Oct 2
2008May 11Sep 24May 11Oct 13
2007Apr 17Sep 14Apr 14Oct 22
2006May 10Sep 19May 5Oct 11
2005May 15Oct 5May 3Oct 22
2004May 14Oct 1May 2Nov 1
2003May 20Oct 1May 20Oct 25
2002May 24Sep 22May 24Oct 12
2001May 7Sep 9Apr 23Oct 5
2000May 13Sep 23May 13Sep 24
1999May 17Sep 13Apr 18Sep 28
1998Jun 3Oct 12May 7Nov 3
1997May 20Oct 9May 3Oct 13
1996May 10Sep 25May 5Oct 17
1995May 24Sep 20Apr 27Sep 21
1994May 1Oct 22May 1Oct 24
1993May 2Sep 13Apr 21Sep 14
1992May 26Sep 18Apr 26Oct 8
1991May 6Sep 17May 6Sep 17
1990May 10Oct 6May 10Oct 7
1989May 6Sep 10May 6Oct 16
1988May 4Sep 20Apr 27Oct 7
1987Apr 24Oct 2Apr 14Oct 10
1986May 1Oct 4Apr 16Oct 11
1985May 6Sep 19Apr 9Sep 23
1984May 28Sep 23May 1Sep 25
1983May 14Sep 19May 12Sep 21
1982May 6Oct 7Apr 22Oct 19
1981Apr 14Oct 6Apr 14Oct 6
1980May 8Oct 11May 8Oct 18
1979May 11Oct 10May 11Oct 22
1978Apr 23Oct 3Apr 13Oct 6
1977Apr 5Oct 9Apr 4Oct 11
1976May 6Sep 28May 2Oct 5
1975May 1Sep 21Apr 30Oct 14
1974May 23Sep 28Apr 16Sep 30
1973May 14Sep 17May 14Oct 10
1972May 7Sep 21Apr 24Sep 25
1971May 20Sep 16Apr 28Oct 27
1970May 2Sep 13Apr 23Oct 7
1969Jun 14Oct 5Apr 28Oct 11
1968May 20Oct 2May 20Oct 3
1967May 12Sep 27May 11Oct 10
1966May 19Sep 30May 13Oct 14
1965May 9Sep 15Apr 6Sep 23
1964Apr 19Sep 26Apr 8Sep 27
1963May 22Oct 27May 22Oct 28
1962Apr 17Sep 9Apr 15Sep 10
1961Apr 28Sep 25Apr 28Sep 30
1960May 6Oct 15Apr 30Oct 18
1959May 15Sep 29Apr 22Sep 30
1958Apr 30Sep 25Apr 29Sep 30
1957Apr 17Sep 19Apr 13Oct 23
1956May 3Oct 25Apr 30Oct 29
1955Apr 28Oct 22Apr 7Oct 23
1954May 4Sep 21May 4Oct 25
1953May 14Sep 21May 13Oct 26
1952Apr 14Oct 5Apr 14Oct 5
1951Jun 2Sep 26Apr 23Sep 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.