Last Frost Day

Frost history / Chicago Palwaukee Ap, IL

Chicago Palwaukee Ap, IL: frost dates by year

Last spring and first fall frost at NOAA station USW00004838, 1996 to 2024, measured from daily minimum temperatures.

Elevation 636 ft, 42.121, -87.905. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 22Oct 22
EarliestApr 1 (2017)Oct 1 (2003)
LatestMay 9 (2020)Nov 13 (2022)
Trend1.6 days later per decade7.2 days later per decade
Years with data2828

At 28°F (hard freeze) the median last spring date is Apr 2 and the median first fall date is Nov 8.

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 16Mar 31Apr 15Apr 30May 152000201020201997: Apr 181998: Apr 51999: Apr 192000: Apr 222001: Apr 192002: Apr 232003: Apr 232004: May 32005: May 32006: Apr 262007: Apr 162008: Apr 302009: Apr 172010: Apr 282011: Apr 212012: Apr 242013: Apr 212014: Apr 162015: Apr 242016: Apr 142017: Apr 12018: Apr 292019: Apr 282020: May 92021: Apr 222022: Apr 172023: Apr 272024: Apr 25

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 11Nov 262000201020201996: Oct 111998: Oct 221999: Oct 242000: Oct 72001: Oct 72002: Oct 202003: Oct 12004: Oct 172005: Oct 232006: Oct 122007: Oct 282008: Oct 272009: Oct 102010: Oct 222011: Oct 302012: Oct 82013: Oct 222014: Nov 12015: Oct 172016: Nov 122017: Nov 62018: Oct 132019: Oct 312020: Oct 282021: Nov 22022: Nov 132023: Oct 302024: Oct 17

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
2024Apr 25Oct 17Mar 28Nov 26
2023Apr 27Oct 30Apr 2Oct 30
2022Apr 17Nov 13Mar 29Nov 13
2021Apr 22Nov 2Apr 2Nov 4
2020May 9Oct 28Apr 16Oct 31
2019Apr 28Oct 31Apr 1Oct 31
2018Apr 29Oct 13Apr 8Nov 9
2017Apr 1Nov 6Mar 23Nov 8
2016Apr 14Nov 12Apr 9Nov 20
2015Apr 24Oct 17Mar 29Nov 8
2014Apr 16Nov 1Apr 16Nov 2
2013Apr 21Oct 22Apr 4Nov 8
2012Apr 24Oct 8Mar 5Nov 13
2011Apr 21Oct 30Apr 1Nov 17
2010Apr 28Oct 22Mar 26Nov 6
2009Apr 17Oct 10Mar 30Nov 12
2008Apr 30Oct 27Apr 2Nov 10
2007Apr 16Oct 28Apr 10Nov 15
2006Apr 26Oct 12Apr 9Oct 25
2005May 3Oct 23Mar 28Nov 16
2004May 3Oct 17Apr 5Nov 13
2003Apr 23Oct 1Apr 10Nov 7
2002Apr 23Oct 20Apr 6Nov 1
2001Apr 19Oct 7Apr 18Nov 9
2000Apr 22Oct 7Apr 12Nov 11
1999Apr 19Oct 24Mar 27Oct 24
1998Apr 5Oct 22Mar 24Nov 7
1997Apr 18no dataApr 18no data
1996no dataOct 11no dataOct 11

"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.