The National Weather Services has issued a severe thunderstorm warning for Hammond, Gary and Calumet City as strong storms move through Lake County.
The warning, issued at 4:11 p.m., will extend through 5:15 p.m. Monday.
The storms are capable of producing quarter-sized hail and winds of up to 60 mph, according to the National Weather Service.
NWS Chicago is advising residents to move inside until the storm has passed.
A special marine warning has also been issued including Lake Michigan shores from Wilmette Harbor to Michigan City. This warning remains in effect until 5:45 p.m., according to NWS.