Last Frost Day

Frost history / Clear Lake, SD

Clear Lake, SD: frost dates by year

Last spring and first fall frost at NOAA station USC00391777, 1955 to 2019, measured from daily minimum temperatures.

Elevation 1,812 ft, 44.758, -96.683. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 10Sep 29
EarliestApr 15 (2007)Sep 10 (1959)
LatestMay 28 (1965)Oct 28 (1963)
Trend1.5 days earlier per decade1.7 days later per decade
Years with data6061

At 28°F (hard freeze) the median last spring date is Apr 29 and the median first fall date is Oct 9.

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 141960197019801990200020101956: May 41957: May 51958: May 231959: May 151960: May 111961: May 31963: May 221964: May 131965: May 281966: May 121967: May 201968: May 181969: Apr 291970: May 21971: May 261972: May 41973: May 161974: May 151975: May 151976: May 71977: Apr 241978: Apr 211979: May 211980: May 141981: May 191982: May 81983: May 251984: May 91986: May 181987: Apr 211988: May 131989: May 71990: May 101991: May 51992: May 51993: Apr 301994: May 61995: Apr 271996: May 131997: May 201998: Apr 172000: Apr 212001: Apr 242002: May 242003: Apr 222004: May 142005: May 152006: Apr 262007: Apr 152008: May 112009: May 102010: May 92011: May 42012: Apr 212013: May 132015: May 192016: May 152017: May 22018: Apr 282019: May 20

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 111960197019801990200020101955: Sep 111956: Sep 141957: Sep 201958: Sep 301959: Sep 101960: Oct 21961: Sep 251962: Sep 201963: Oct 281964: Sep 271965: Sep 231966: Oct 11967: Sep 271968: Oct 31969: Oct 81970: Sep 261971: Sep 171972: Sep 291973: Oct 161974: Sep 221975: Oct 11977: Oct 61978: Oct 71979: Oct 41980: Sep 261981: Oct 21982: Sep 251983: Sep 211984: Sep 251985: Sep 241986: Oct 41987: Oct 21988: Oct 41989: Sep 231990: Sep 231991: Sep 191992: Sep 281993: Sep 151994: Oct 241995: Sep 221996: Oct 31997: Oct 131998: Oct 11999: Oct 12000: Sep 232002: Sep 272003: Sep 252004: Oct 22005: Oct 62006: Sep 202007: Oct 272008: Oct 162009: Oct 92010: Oct 152011: Sep 152012: Sep 222013: Oct 132014: Oct 42015: Oct 162016: Oct 72018: Sep 29

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

"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.