Last Frost Day

Frost history / Lancaster 4 Wsw, WI

Lancaster 4 Wsw, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00474546, 1951 to 2025, measured from daily minimum temperatures.

Elevation 1,040 ft, 42.828, -90.789. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 29Oct 9
EarliestApr 5 (1987)Sep 16 (2011)
LatestMay 29 (1965)Oct 31 (1971)
Trend1.3 days earlier per decade0.7 days later per decade
Years with data7375

At 28°F (hard freeze) the median last spring date is Apr 18 and the median first fall date is Oct 19.

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: Apr 151953: May 131954: May 81955: Apr 71956: May 161957: May 41958: May 51959: Apr 211960: May 91961: May 261962: Apr 201963: May 11964: Apr 151965: May 291966: May 111967: May 221968: Apr 251969: May 121970: May 61971: May 121972: Apr 251975: Apr 221976: May 81977: May 91978: May 61979: Apr 161980: May 71981: May 121982: Apr 271983: May 91984: May 11985: Apr 101986: Apr 231987: Apr 51988: Apr 271989: May 71990: May 101991: Apr 211992: May 61993: Apr 211994: May 11995: Apr 111996: Apr 301997: May 151998: Apr 171999: Apr 242000: Apr 132001: Apr 192002: May 32003: Apr 222004: May 32005: May 42006: Apr 92007: Apr 142008: Apr 152009: Apr 152010: Apr 92011: May 42012: Apr 112013: May 122014: Apr 192015: Apr 272016: May 162017: Apr 282018: Apr 292019: Apr 292020: May 92021: May 112022: Apr 282023: Apr 262024: Apr 242025: Apr 16

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 281952: Oct 31953: Oct 71954: Oct 171955: Oct 161956: Sep 201957: Oct 101958: Oct 11959: Oct 121960: Oct 191961: Sep 281962: Oct 231963: Oct 291964: Sep 281965: Oct 221966: Oct 161967: Sep 291968: Oct 41969: Oct 141970: Oct 101971: Oct 311972: Sep 301973: Oct 301974: Sep 221975: Sep 261976: Sep 221977: Oct 111978: Oct 81979: Oct 71980: Oct 41981: Oct 21982: Oct 161983: Oct 131984: Sep 261985: Sep 281986: Oct 61987: Oct 31988: Oct 41989: Sep 231990: Oct 111991: Sep 201992: Oct 171993: Oct 91994: Oct 101995: Sep 221996: Oct 31997: Oct 141998: Oct 141999: Oct 42000: Oct 62001: Oct 62002: Oct 72003: Sep 292004: Oct 22005: Oct 82006: Oct 122007: Oct 232008: Oct 162009: Oct 102010: Oct 222011: Sep 162012: Oct 102013: Oct 202014: Oct 52015: Oct 172016: Oct 132017: Oct 272018: Oct 122019: Oct 122020: Oct 42021: Oct 232022: Oct 82023: Oct 112024: Oct 162025: Oct 23

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

"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.