Official Extreme Weather Records for Chicago, IL
National Weather Service United States Department of Commerce

Last Updated: 8/25/2023

Temperature (in degrees Fahrenheit)
Highest Temperature 105 degrees on July 24, 1934
Lowest Temperature -27 degrees on January 20, 1985
   
Warmest Month 81.3 degrees in July 1955
Coldest Month 10.1 degrees in January 1977
   
Warmest Season 76.7 degrees in Summer of 2020
Coldest Season 18.3 degrees in Winter of 1903-04
   
Warmest Year 54.5 degrees in 2012
Coldest Year 45.1 degrees in 1875
   
Highest Heat Index

Hourly observations only:

118 degrees on July 13, 1995 and August 24, 2023

Including intra-hour observations (since 1996):

120 degrees on August 24, 2023

   
Lowest Relative Humidity 12% on April 20, 2019
   
Highest Dew Point 83 degrees on July 30, 1999
Lowest Dew Point -40 degrees on January 20, 1985

 

Precipitation (in inches)
Wettest Year 50.86 in 2008
Driest Year 22.22 in 1962
   
Wettest Season 23.48 Summer (Jun – Aug) of 1987
Driest Season 1.60 Winter (Dec – Feb) of 2002 - 2003
   
Wettest Month 17.10 in August 1987
Driest Month 0.01 in September 1979
   
Greatest in 24 Hours 9.35 on August 13th-14th 1987
Greatest Calendar Day 6.86 on July 23, 2011

 

Snowfall (in inches)
Seasonal (Jul – Jun) Greatest 89.7 in 1978 - 1979
Seasonal (Jul – Jun) Least 9.8 in 1920 - 1921
   
Winter (Dec – Feb) Greatest 80.6 in 1978 – 1979
Winter (Dec – Feb) Least 5.7 in 1930 - 1931
   
Greatest Total:  
Month 42.5 in January, 1918
Storm 23.0 on January 26 – 27, 1967
24 Hours 20.0 on February 1-2, 2011
Calendar Day 18.6 on January 2, 1999
Snow Depth 29 inches on January 14, 1979

 

Pressure (in inches of Mercury)
Highest 30.98 on Feb 16, 1989
Lowest 28.70 on March 12, 1923

 

Wind (in mph)
Highest Gust 87 on February 12, 1894
Coldest Wind Chill -82 on December 24, 1983