CHICAGO, IL (CHICAGO MIDWAY INTERNATIONAL AIRPORT)

Overview:
Situated on the southwestern shores of Lake Michigan, Chicago experiences a wide range of weather that is often influenced by the lake. Lake breezes moderate temperatures during the spring and fall. Summer temperatures are often increased by an Urban Heat Island effect from the large metro area, and heat index values of 100°F or more occur about six days per year on average.

Precipitation is often aided by increased evaporation of water from Lake Michigan. While snowfall is plentiful during the winter months, more than half of the city’s precipitation falls from April through August. Severe weather is not uncommon during the spring and summer mainly due to thunderstorms, while flash flooding is a major concern due to a large number of impervious surfaces in the metro area.

State/ Province ID: IL

Station ID: C00111577

Directory Name: CHICAGO_MIDWAY_AP_3SW__IL_C00111577

Elevation: 189.00m

The resources presented here were developed in cooperation with the Office of the Michigan State Climatologist using data from the National Centers for Environmental Information. For more information regarding our data sources, quality control, and methodology, please see our Historical Climatologies: Quality Control reference guide.

Jump

Temperatures
Precipitation
Back to Top
Back to Station Map

Recent Climate Summary, 1991-2020


Average Temperature	52.1°F11.2°C
Average Low Temperature	44.0°F6.7°C
Average High Temperature	60.2°15.7°C
Days/Year that exceed 90°F	16.1
Days/Year that fall below 32°F	100.2
Lowest Annual Average Temperature	49.6°F9.8°C
Highest Annual Average Temperature	55.4°F13.0°C
Average Annual Total Precipitation	40.9 in103.8 cm
Lowest Annual Precipitation Total	24.6 in62.5 cm
Highest Annual Precipitation Total	53.9 in137.0 cm
Days/Year that exceed 1.25" of Precipitation	5.4

Temperature

Click on the following links to be taken to the corresponding portion of the page.

Monthly Average Temperature
How Temperatures are Changing
- Changes in Average Temperature – Includes a summary table of the average annual and seasonal temperature changes, and time series graphs of how the annual low, average, and high temperatures compare to the long term average plotted for every year on record.
- Cold Temperatures – View time series plots of the number of days per year below 32°F and the number of heating degree days per year to see how cold days are changing.
- Hot Temperatures – View time series plots of the number of days per year above 90°F and the number of cooling degree days per year to see how hot days are changing.
- Growing Season Changes – View a time series of the annual number of days in the freeze-free period.

Monthly Average Temperature

Changes in Average Temperature, 1951-2025.


	°F°C
Annual average temperature	2.81.6
Winter average temperature	4.02.2
Spring average temperature	3.01.7
Summer average temperature	2.21.2
Fall average temperature	2.31.3

Annual High and Low Temperature Departure

Cold Temperatures

¹Heating Degree Days (HDDs) are indexed units, not actual days, that roughly describe the demand to heat a building. HDDs accumulate on days colder than 65°F when heating is required. Every degree below 65°F is added to the annual total for an annual HDD value, which is plotted in the figure.

Hot Temperatures

²Cooling Degree Days (CDDs) are indexed units, not actual days, that roughly describe the demand to cool a building. CDDs accumulate on days warmer than 65°F when cooling is required. Every degree above 65°F is added to the annual total for an annual CDD value, which is plotted in the figure.

Growing Season Changes

Precipitation