The National Weather Service in Chicago issued a High Wind Warning that will remain in effect until 5 p.m. Wednesday.
A high wind warning means a "hazardous high wind event" is expected or occurring, the NWS said.
A wind advisory was issued by the National Weather Service for the entire metro Chicago area and parts of northwest Indiana earlier in the day.
The advisory went into effect at 9 a.m. and will remain until 6 p.m., warning of powerful winds that will gain speed throughout the day, gusting up to 55 mph.
Willis Tower's Skydeck was closed Wednesday morning ahead of the anticipated weather. The popular attraction was scheduled to be open until 8 p.m., but was shut down for the day just before 9 a.m.
"The Skydeck is closed currently due to high winds," the venue announced on its Twitter page. "Please check back for updates."
Driving may also become difficult due to the strong winds, the National Weather Service warned, especially for high-profile vehicles.
The NWS urged commuters to use extra caution as loose objects will also likely be blown around.
Wednesday will be mostly sunny and cooler than recent days. Highs will be in the mid 40s to low 50s north of I-88, and slightly warmer south of I-88, reaching 50 to 55 degrees.
Sunny skies give way to partial cloud cover in the evening as conditions turn colder and temperatures fall into the upper 20s inland and mid 30s in the city and across Northwest Indiana. Winds ease early before shifting north overnight, traveling at an expected 5 to 15 mph.