Last Frost Day

Frost history / Summit 1 W, SD

Summit 1 W, SD: frost dates by year

Last spring and first fall frost at NOAA station USC00398116, 1957 to 2025, measured from daily minimum temperatures.

Elevation 1,955 ft, 45.304, -97.063. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 16Sep 23
EarliestApr 18 (2007)Aug 31 (1987)
LatestJun 14 (1969)Oct 27 (1963)
Trend0.7 days earlier per decade1.7 days later per decade
Years with data6767

At 28°F (hard freeze) the median last spring date is May 6 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 2919601970198019902000201020201957: May 91958: May 61959: May 221960: May 111961: May 161962: Apr 281963: May 221964: Jun 41965: May 281966: May 131967: May 201968: May 181969: Jun 141970: May 261971: May 261972: May 71973: May 141974: May 241975: May 151976: May 71977: Apr 241978: May 21979: May 201980: May 121983: May 241984: May 261985: Jun 51986: May 181987: Apr 221988: May 161989: Jun 91990: Jun 41991: May 61992: Jun 71993: Jun 11994: May 91995: May 171996: May 121997: May 201998: Jun 71999: May 132000: May 192001: Apr 242002: May 242003: May 202004: May 152005: May 152006: May 122007: Apr 182008: May 212009: May 172010: May 92011: May 32012: May 302013: May 122014: May 162015: May 302016: May 152017: May 212018: May 22019: May 202020: May 152021: May 282022: May 222023: May 32024: Apr 302025: Apr 30

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201957: Sep 161958: Sep 271959: Sep 101960: Oct 21961: Sep 251962: Sep 201963: Oct 271964: Sep 111965: Sep 51966: Oct 91967: Sep 271968: Oct 31969: Oct 81970: Sep 131971: Sep 161972: Sep 211973: Sep 201974: Sep 31975: Sep 121976: Sep 201977: Oct 21978: Oct 71979: Sep 141982: Sep 211983: Sep 211984: Sep 151985: Sep 211986: Sep 71987: Aug 311988: Oct 21989: Sep 231990: Sep 231991: Sep 181992: Sep 221993: Sep 151994: Sep 261995: Sep 201996: Sep 291997: Oct 131998: Sep 221999: Sep 212000: Sep 212001: Sep 242002: Sep 242003: Sep 192004: Sep 282005: Sep 292006: Sep 202007: Sep 122008: Oct 142009: Oct 82010: Oct 152011: Sep 152012: Sep 182013: Oct 132014: Oct 42015: Oct 92016: Sep 142017: Oct 102018: Sep 282019: Oct 102020: Sep 92021: Oct 162022: Sep 282023: Oct 72024: Oct 42025: Oct 8

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

"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.