Dangerous heat wave expands across the Heartland...
A dangerous combination of heat and humidity continues!
Upper level high pressure will intensify over the middle of the nation. A very hot and humid air mass will drift eastward out of the Plains and into Illinois the next few days, then become nearly stationary. Central Illinois has begun to feel the oppressive heat and humidity early this week. However, even higher heat and humidity levels are expected through the rest of the week. Current indications are that this heat wave will last well into the weekend.
The combination of temperatures in the 90s and dew points in the mid- to upper 70s will produce dangerous heat index values of 105 to 115 degrees from the late-morning hours into early-evening hours each day.