Heat Advisory Issued

11:00am Update:  Heat Advisory now issued for Winnebago, Boone, McHenry, Ogle, Lee and DeKalb counties from Noon Friday through Midnight.

The Excessive Heat Watch that had been issued for Stephenson, Jo Daviess, Carroll and Whiteside counties yesterday has been replaced by a Heat Advisory for Friday afternoon and evening.  The Heat Advisory also extends into Wisconsin and covers Green, Rock and Walworth counties. 

A Heat Advisory also extends through the upper Midwest while Excessive Heat Warnings have been issued for sections of Missouri.  While we won't see triple digit heat like our neighbors to the west will, temperatures will rise into the middle, and possibly upper 90s, by Friday afternoon.  Along with the rising temperatures dew points will rise into the low 70s creating a fairly humid atmosphere.  Heat Index values could reach 100° or better during the afternoon.  Even though the rest of northern Illinois isn't under any heat headlines just yet (those counties are handled under a different weather service) it's still going to be very humid out.  The heat will continue through the weekend before we return back to average by the middle of next week.