* WHAT...Peak heat indices of 100 to 105 degrees expected Tuesday and Wednesday afternoons.
* WHERE...Portions of northern and central Illinois near and south of I-80, as well as all of northwest Indiana.
* WHEN...For the first Heat Advisory, from noon CDT to 9 PM CDT Tuesday. For the second Heat Advisory, from noon CDT to 9 PM CDT Wednesday.
* IMPACTS...Hot temperatures and high humidity may cause heat illnesses.