Heat index possibly up to 105 Monday, advisory warns

The National Weather Service in Chicago is warning of dangerous heat and humidity Monday.

The advisory warns of a heat indexes reaching around 105 during the day Monday, with temperatures reaching the mid-90s. The heat advisory is in effect from 11 a.m. to 7 p.m. in most of the Chicago area.

The advisory applies to counties including Cook, DuPage and Kane counties, and cites Aurora, Elgin and Wheaton.

"The combination of heat and humidity will lead to hazardous conditions, particularly for the elderly and those with pre-existing health conditions," the advisory says.

The heat and humidity could lead to heat illnesses. The service advises drinking plenty of fluids, staying in air-conditioned rooms and staying out of the sun, while checking on relatives and neighbors.

"The Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air-conditioned environments," the service says. "Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency - call 911."

Rain is expected to come through Tuesday to bring cooler days Wednesday and Thursday.