Last Frost Day

Frost history / De Smet, SD

De Smet, SD: frost dates by year

Last spring and first fall frost at NOAA station USC00392302, 1951 to 2025, measured from daily minimum temperatures.

Elevation 1,705 ft, 44.383, -97.550. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 7Oct 3
EarliestApr 6 (1977)Sep 10 (2020)
LatestMay 28 (1965)Oct 28 (1963)
Trend0.6 days earlier per decade1.4 days later per decade
Years with data7375

At 28°F (hard freeze) the median last spring date is Apr 25 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 1419601970198019902000201020201951: Apr 231952: May 111953: May 141954: May 101955: May 81957: May 41958: May 11959: May 151960: May 71961: May 91962: Apr 231963: May 221964: May 121965: May 281966: May 131967: May 201968: May 191969: Apr 291970: May 21971: May 121972: Apr 241973: May 121974: May 151975: Apr 211976: May 71977: Apr 61978: Apr 251979: May 111980: May 91981: May 101982: Apr 271983: May 141984: May 91985: Apr 261986: Apr 221987: Apr 111988: Apr 261989: May 61990: May 91991: May 71992: Apr 271993: Apr 251994: May 141995: Apr 271996: May 111997: May 131998: Apr 171999: Apr 182000: Apr 212001: Apr 232002: May 232004: May 142005: May 152006: Apr 262007: Apr 152008: May 142009: May 162010: May 82011: May 32012: Apr 162013: May 32014: May 162015: Apr 222016: May 142017: May 212018: Apr 282019: May 202020: May 102021: May 112022: Apr 282023: May 32024: Apr 242025: Apr 29

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 241952: Sep 231953: Sep 211954: Sep 221955: Oct 141956: Sep 301957: Sep 201958: Sep 301959: Oct 81960: Oct 191961: Sep 241962: Sep 201963: Oct 281964: Sep 271965: Sep 231966: Oct 11967: Sep 271968: Oct 31969: Oct 81970: Sep 261971: Oct 81972: Sep 261973: Oct 161974: Sep 221975: Oct 101976: Sep 271977: Oct 21978: Oct 71979: Oct 41980: Oct 31981: Oct 21982: Sep 251983: Sep 211984: Sep 251985: Sep 241986: Oct 41987: Oct 71988: Oct 41989: Sep 231990: Sep 231991: Sep 181992: Sep 281993: Oct 21994: Oct 91995: Sep 221996: Oct 31997: Oct 131998: Oct 11999: Oct 12000: Sep 242001: Oct 52002: Oct 72003: Sep 252004: Oct 22005: Oct 62006: Sep 202007: Oct 242008: Oct 162009: Oct 82010: Oct 272011: Oct 182012: Sep 222013: Oct 162014: Oct 42015: Oct 162016: Oct 72017: Oct 102018: Oct 42019: Oct 102020: Sep 102021: Oct 152022: Oct 72023: Oct 72024: Oct 142025: Oct 22

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
2025Apr 29Oct 22Apr 29Oct 22
2024Apr 24Oct 14Apr 24Oct 14
2023May 3Oct 7Apr 25Oct 7
2022Apr 28Oct 7Apr 26Oct 7
2021May 11Oct 15May 11Oct 31
2020May 10Sep 10Apr 22Oct 15
2019May 20Oct 10Apr 14Oct 11
2018Apr 28Oct 4Apr 22Oct 4
2017May 21Oct 10May 2Oct 10
2016May 14Oct 7May 14Oct 13
2015Apr 22Oct 16Apr 22Nov 12
2014May 16Oct 4Apr 17Oct 31
2013May 3Oct 16May 3Oct 24
2012Apr 16Sep 22Apr 11Sep 22
2011May 3Oct 18Apr 18Oct 19
2010May 8Oct 27Apr 8Oct 28
2009May 16Oct 8Apr 11Oct 9
2008May 14Oct 16May 3Oct 16
2007Apr 15Oct 24Apr 13Oct 28
2006Apr 26Sep 20Apr 8Oct 11
2005May 15Oct 6May 3Oct 7
2004May 14Oct 2Apr 13Oct 2
2003no dataSep 25no dataOct 1
2002May 23Oct 7May 23Oct 13
2001Apr 23Oct 5Apr 17Oct 5
2000Apr 21Sep 24Apr 16Oct 6
1999Apr 18Oct 1Apr 18Oct 2
1998Apr 17Oct 1Apr 4Oct 13
1997May 13Oct 13May 13Oct 13
1996May 11Oct 3Apr 27Oct 23
1995Apr 27Sep 22Apr 14Sep 23
1994May 14Oct 9May 3Oct 23
1993Apr 25Oct 2Apr 19Oct 8
1992Apr 27Sep 28Apr 27Sep 28
1991May 7Sep 18May 7Sep 18
1990May 9Sep 23May 9Oct 17
1989May 6Sep 23May 6Sep 23
1988Apr 26Oct 4Apr 26Oct 4
1987Apr 11Oct 7Apr 3Oct 7
1986Apr 22Oct 4Apr 21Oct 12
1985Apr 26Sep 24Apr 9Oct 9
1984May 9Sep 25May 1Sep 26
1983May 14Sep 21Apr 18Sep 21
1982Apr 27Sep 25Apr 20Oct 20
1981May 10Oct 2May 10Oct 22
1980May 9Oct 3May 8Oct 12
1979May 11Oct 4May 3Oct 4
1978Apr 25Oct 7Apr 21Oct 7
1977Apr 6Oct 2Apr 6Oct 6
1976May 7Sep 27May 6Oct 6
1975Apr 21Oct 10Apr 20Oct 25
1974May 15Sep 22May 3Sep 30
1973May 12Oct 16Apr 27Oct 28
1972Apr 24Sep 26Apr 24Oct 17
1971May 12Oct 8Apr 25Oct 28
1970May 2Sep 26Apr 4Oct 10
1969Apr 29Oct 8Apr 28Oct 14
1968May 19Oct 3May 5Oct 4
1967May 20Sep 27May 4Oct 10
1966May 13Oct 1May 9Oct 16
1965May 28Sep 23May 28Sep 24
1964May 12Sep 27Apr 14Oct 9
1963May 22Oct 28May 22Oct 29
1962Apr 23Sep 20Apr 15Oct 23
1961May 9Sep 24May 2Sep 28
1960May 7Oct 19May 7Oct 19
1959May 15Oct 8May 15Oct 9
1958May 1Sep 30Apr 29Sep 30
1957May 4Sep 20Apr 14Oct 18
1956no dataSep 30no dataOct 9
1955May 8Oct 14Apr 7Oct 15
1954May 10Sep 22May 4Oct 27
1953May 14Sep 21May 13Oct 26
1952May 11Sep 23Apr 16Oct 4
1951Apr 23Sep 24Apr 22Sep 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.