Last Frost Day

Frost history / Piper City, IL

Piper City, IL: frost dates by year

Last spring and first fall frost at NOAA station USC00116819, 1969 to 2012, measured from daily minimum temperatures.

Elevation 670 ft, 40.757, -88.183. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 26Oct 12
EarliestApr 5 (1998)Sep 23 (1974)
LatestMay 22 (2002)Nov 3 (1973)
Trend3.5 days earlier per decadelittle change (less than half a day per decade)
Years with data4341

At 28°F (hard freeze) the median last spring date is Apr 11 and the median first fall date is Oct 25.

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 30197019801990200020101969: Apr 301970: May 61971: May 31972: Apr 261973: Apr 171974: May 71975: Apr 211976: May 71977: May 101978: May 31979: May 11980: Apr 261981: May 121982: Apr 281983: May 91984: May 161986: Apr 221987: May 51988: Apr 211989: May 61990: Apr 181991: Apr 211992: May 71993: Apr 211994: Apr 231995: Apr 141996: Apr 181997: Apr 281998: Apr 51999: Apr 252000: Apr 262001: Apr 192002: May 222003: Apr 242004: Apr 152005: May 52006: Apr 112007: Apr 162008: May 12009: Apr 182010: Apr 92011: Apr 82012: Apr 27

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 11197019801990200020101969: Oct 141970: Oct 161971: Nov 11972: Oct 151973: Nov 31974: Sep 231975: Oct 261976: Sep 241977: Oct 131978: Oct 81979: Oct 101980: Oct 51981: Oct 31982: Oct 171984: Sep 291986: Oct 141987: Oct 21988: Oct 41989: Sep 231990: Oct 181991: Oct 151992: Oct 171993: Sep 301994: Oct 111995: Sep 231996: Oct 111997: Oct 151998: Oct 221999: Oct 152000: Oct 72001: Oct 72002: Oct 142003: Oct 22004: Oct 52005: Oct 282006: Oct 122007: Nov 22008: Oct 222009: Oct 112010: Oct 222012: Oct 6

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
2012Apr 27Oct 6Apr 13Nov 1
2011Apr 8no dataApr 8no data
2010Apr 9Oct 22Mar 30Oct 29
2009Apr 18Oct 11Apr 13Nov 12
2008May 1Oct 22Mar 25Oct 28
2007Apr 16Nov 2Apr 11Nov 2
2006Apr 11Oct 12Apr 9Oct 25
2005May 5Oct 28May 5Nov 17
2004Apr 15Oct 5Apr 15Oct 5
2003Apr 24Oct 2Apr 13Oct 2
2002May 22Oct 14Apr 26Oct 14
2001Apr 19Oct 7Apr 17Nov 12
2000Apr 26Oct 7Apr 9Oct 7
1999Apr 25Oct 15Mar 28Oct 24
1998Apr 5Oct 22Mar 24Nov 7
1997Apr 28Oct 15Apr 19Oct 22
1996Apr 18Oct 11Apr 17Oct 31
1995Apr 14Sep 23Apr 6Sep 23
1994Apr 23Oct 11Apr 8Nov 22
1993Apr 21Sep 30Apr 4Oct 31
1992May 7Oct 17Apr 5Oct 19
1991Apr 21Oct 15Apr 1Nov 1
1990Apr 18Oct 18Apr 17Oct 18
1989May 6Sep 23May 6Nov 2
1988Apr 21Oct 4Apr 20Oct 11
1987May 5Oct 2Apr 9Oct 7
1986Apr 22Oct 14Apr 22Nov 2
1984May 16Sep 29Apr 9Nov 2
1983May 9no dataMay 9no data
1982Apr 28Oct 17Apr 11Oct 22
1981May 12Oct 3Mar 23Oct 23
1980Apr 26Oct 5Mar 22Oct 5
1979May 1Oct 10Apr 10Oct 13
1978May 3Oct 8May 3Oct 17
1977May 10Oct 13Apr 29Nov 11
1976May 7Sep 24Apr 13Oct 17
1975Apr 21Oct 26Apr 21Nov 14
1974May 7Sep 23May 7Oct 2
1973Apr 17Nov 3Apr 13Nov 5
1972Apr 26Oct 15Apr 9Oct 19
1971May 3Nov 1May 3Nov 4
1970May 6Oct 16Apr 7Nov 3
1969Apr 30Oct 14Apr 1Oct 23

"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.