Last Frost Day

Frost history / Monmouth 4NW, IL

Monmouth 4NW, IL: frost dates by year

Last spring and first fall frost at NOAA station USC00115772, 1995 to 2025, measured from daily minimum temperatures.

Elevation 724 ft, 40.936, -90.720. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 21Oct 12
EarliestApr 5 (1998)Sep 15 (2007)
LatestMay 16 (1997)Nov 1 (2021)
Trend0.8 days later per decade4.9 days later per decade
Years with data2627

At 28°F (hard freeze) the median last spring date is Apr 14 and the median first fall date is Oct 20.

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 302000201020201997: May 161998: Apr 51999: Apr 202000: Apr 122001: Apr 182002: Apr 262003: Apr 132007: Apr 152008: Apr 292009: Apr 122010: Apr 92011: May 42012: Apr 212013: Apr 212014: Apr 182015: May 12016: Apr 132017: Apr 72018: Apr 292019: Apr 282020: May 92021: Apr 222022: Apr 262023: Apr 242024: Apr 212025: Apr 9

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 112000201020201995: Sep 221996: Oct 111997: Oct 141998: Oct 221999: Sep 212000: Oct 72001: Oct 62002: Oct 132006: Oct 122007: Sep 152009: Oct 102010: Oct 192011: Oct 12012: Oct 62013: Oct 222014: Oct 52015: Oct 172016: Oct 132017: Oct 282018: Oct 152019: Oct 122020: Oct 162021: Nov 12022: Oct 82023: Oct 102024: 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 9Oct 23Apr 9Nov 2
2024Apr 21Oct 16Mar 28Oct 16
2023Apr 24Oct 10Mar 27Oct 30
2022Apr 26Oct 8Apr 19Oct 8
2021Apr 22Nov 1Apr 22Nov 2
2020May 9Oct 16May 9Oct 16
2019Apr 28Oct 12Apr 15Oct 12
2018Apr 29Oct 15Apr 29Oct 16
2017Apr 7Oct 28Mar 23Oct 29
2016Apr 13Oct 13Apr 12Nov 12
2015May 1Oct 17Apr 23Oct 17
2014Apr 18Oct 5Apr 16Nov 1
2013Apr 21Oct 22Apr 20Oct 23
2012Apr 21Oct 6Apr 11Oct 6
2011May 4Oct 1May 4Oct 21
2010Apr 9Oct 19Mar 30Oct 29
2009Apr 12Oct 10Apr 12Oct 10
2008Apr 29no dataApr 2no data
2007Apr 15Sep 15Apr 15Nov 1
2006no dataOct 12no dataOct 12
2003Apr 13no dataApr 10no data
2002Apr 26Oct 13Apr 26Oct 20
2001Apr 18Oct 6Apr 18Oct 17
2000Apr 12Oct 7Apr 12Oct 7
1999Apr 20Sep 21Mar 27Oct 18
1998Apr 5Oct 22Mar 24Nov 5
1997May 16Oct 14Apr 17Oct 22
1996no dataOct 11no dataOct 19
1995no dataSep 22no dataNov 3

"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.