Periods of rain have returned to the Chicago area, with the second round arriving overnight tonight. Waves of rain with occasional thunderstorms are expected to yield rain totals of 0.75"-1" by mid-morning Tuesday.

After a mild and cloudy evening Sunday, the Chicago area is set to experience a week of rapidly changing weather, including rain, cooler temperatures, and even a chance of wet snow.

The Chicago area typically sees its first trace of snow Oct. 31, Roman said. The area's first measurable snow -- 0.1 of an inch or more -- usually comes Nov. 18, Roman said, and the area's first average snow of one inch or more typically occurs Dec. 7.

Hundreds of mourners attend the funeral of Chicago Police Officer Enrique Martinez. (Credit: WFLD Chicago)