07/03/2012 11:11 am ET

Chicago Heat Wave: Heat Advisory In Effect Wednesday Amid Triple-Digit Heat Index

As the Chicago area enters into its fourth consecutive day of 90-degree-plus heat Tuesday, the sweltering conditions are only expected to get more balmy Wednesday when the area goes under an excessive heat watch through that evening.

The Chicago Tribune reports that the area is expected to see an eight-day run of 90-degree weather, conditions made even more serious as thousands of people in the city's western suburbs remain without power.

As of early Tuesday, some 48,000 Chicago-area ComEd customers do not have power, according to the Chicago Sun-Times. Initially, some 100,000 area residents were hit by power outages on the heels of a swift-moving storm that blasted through the area Sunday. ComEd has estimated that it could take several days for all the impacted customers to get their lights turned back on.

NBC Chicago reports that more isolated thunderstorms could be on the way Tuesday afternoon. Meanwhile, the mercury could reach 100 degrees on Independence Day -- and more thunderstorms are possible during the afternoon on the holiday.

Relief from the oppressive heat is not expected to arrive until the upcoming weekend, according to the Chicago Weather Center.

Area residents without air conditioning are urged to go to a cooling center -- such as a public library or police station to help them beat the heat.

Some scientists say the widespread heat wave is offering a glimpse into some of the worst effects of global warming.