Last Frost Day

Frost history / Prentice #2, WI

Prentice #2, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00476859, 1951 to 2013, measured from daily minimum temperatures.

Elevation 1,540 ft, 45.545, -90.302. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianJun 3Sep 11
EarliestMay 9 (1991)Aug 5 (1957)
LatestJul 31 (1960)Oct 7 (2002)
Trend3.9 days earlier per decade4.6 days later per decade
Years with data5956

At 28°F (hard freeze) the median last spring date is May 19 and the median first fall date is Sep 24.

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)

Apr 30May 15May 30Jun 14Jun 29Jul 14Jul 29Aug 131960197019801990200020101951: May 231952: Jun 11953: Jun 71954: Jun 61955: May 301956: Jun 31957: Jun 71958: Jun 171959: May 241960: Jul 311961: Jun 251962: Jun 121963: Jun 221964: Jul 131965: May 291966: Jun 161967: Jul 51968: May 211969: Jun 201970: Jun 191971: May 281972: Jul 41973: May 301974: Jun 11975: Jun 81976: May 251977: Jun 91978: Jun 81979: Jun 231980: Jun 101981: May 191982: Jun 161983: Jun 11984: May 301985: Jun 31986: Jun 21987: Jun 41988: Jun 91989: Jun 101990: Jun 41991: May 91992: Jun 211993: Jun 51994: Jun 21995: May 181996: May 251997: May 211998: Jun 71999: May 262000: May 202001: May 132002: May 212003: Jun 12004: May 282005: May 162008: May 222009: Jun 62010: May 152013: May 24

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 121960197019801990200020101952: Sep 31953: Sep 71954: Sep 231955: Sep 71956: Aug 201957: Aug 51958: Aug 221959: Sep 111960: Aug 151961: Sep 151962: Aug 171963: Aug 141964: Aug 91965: Aug 291966: Sep 151967: Aug 111968: Aug 271969: Sep 91970: Aug 311971: Sep 151972: Sep 221973: Sep 121974: Aug 301975: Aug 181976: Aug 151977: Aug 181978: Sep 221979: Aug 151980: Sep 171981: Sep 201982: Sep 211983: Sep 131984: Sep 151985: Sep 251986: Aug 281987: Sep 251988: Sep 61989: Sep 121990: Oct 21991: Sep 201992: Sep 191993: Sep 111994: Sep 21995: Sep 81997: Sep 211998: Sep 221999: Sep 212000: Sep 162001: Sep 252002: Oct 72003: Sep 292004: Aug 132008: Aug 252009: Sep 302010: Sep 262012: Sep 19

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

"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.