October 6, 2015; 4:42 AM ET
Temperatures will rebound into midweek in Chicago ahead of the next storm system. more >
Classes were canceled at the College of DuPage after a threat forced the evacuation of every building on campus.
Tropical cyclones presented trouble around the world this week, while heavy snow fell in parts of Alaska.
Sinkholes can be man-induced or natural, AccuWeather Meteorologist Jim Andrews said. Weather extremes such as heavy rains or drought can lead to sinkhole development.
Short-Range Weather forecast overview for the North Central United States
The summerlike temperatures that continued well beyond August will result in the warmest September on record for many locations across the Midwest and the Northeast.