Last Frost Day

Frost history / Chilton, WI

Chilton, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00471568, 1951 to 2025, measured from daily minimum temperatures.

Elevation 840 ft, 44.033, -88.147. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 9Oct 7
EarliestApr 16 (2007)Sep 20 (1956)
LatestJun 2 (1956)Nov 2 (2024)
Trend2.3 days earlier per decade2.4 days later per decade
Years with data7375

At 28°F (hard freeze) the median last spring date is Apr 24 and the median first fall date is Oct 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)

Mar 31Apr 15Apr 30May 15May 30Jun 1419601970198019902000201020201951: May 131952: May 71953: May 151954: May 201955: May 171956: Jun 21957: May 161958: May 231959: Apr 211960: May 131961: May 231962: Apr 201963: May 231964: May 141965: May 291966: May 141967: May 221968: May 101970: May 71971: May 271972: May 91973: May 191974: May 101975: Apr 261976: May 121977: May 101978: May 31979: May 51980: May 91981: May 191982: Apr 281983: May 171984: May 141985: Apr 171986: May 31987: Apr 301988: May 251989: May 91990: May 101991: May 21992: May 241993: May 171994: May 271995: May 11996: May 141997: May 221998: Apr 281999: Apr 242000: Apr 302001: Apr 192002: May 212003: May 42005: Apr 252006: May 62007: Apr 162008: May 282009: Apr 232010: May 102011: May 42012: Apr 302013: May 132014: Apr 232015: Apr 262016: May 152017: May 82018: Apr 302019: Apr 292020: May 132021: Apr 262022: May 42023: Apr 272024: Apr 262025: Apr 17

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 291952: Oct 31953: Oct 71954: Oct 71955: Oct 11956: Sep 201957: Sep 271958: Oct 11959: Oct 191960: Oct 181961: Sep 291962: Sep 291963: Oct 291964: Sep 281965: Sep 271966: Sep 261967: Oct 121968: Oct 51969: Oct 141970: Oct 161971: Nov 11972: Oct 91973: Sep 201974: Sep 221975: Oct 21976: Sep 221977: Oct 71978: Oct 81979: Oct 141980: Oct 31981: Oct 21982: Oct 161983: Sep 241984: Sep 261985: Oct 111986: Oct 101987: Oct 31988: Oct 51989: Sep 231990: Oct 121991: Sep 261992: Sep 231993: Sep 301994: Oct 111995: Sep 231996: Oct 31997: Oct 171998: Oct 221999: Oct 42000: Oct 72001: Oct 72002: Oct 142003: Oct 22004: Oct 52005: Oct 102006: Oct 122007: Oct 282008: Oct 42009: Oct 12010: Oct 42011: Oct 232012: Oct 122013: Oct 222014: Oct 192015: Oct 172016: Oct 142017: Oct 292018: Oct 132019: Oct 252020: Oct 172021: Oct 222022: Oct 192023: Oct 302024: Nov 22025: Oct 24

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

"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.