Extreme Heat Warning

* WHAT...Dangerously hot conditions with heat index values around 105 expected each afternoon.

* WHERE...Central Cook, Northern Cook, and Southern Cook Counties.

* WHEN...Until midnight CDT Thursday Night.

* IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events.

* ADDITIONAL DETAILS...Dangerous heat is now expected to persist through Thursday. Thunderstorms may begin to bring some relief from the heat by Thursday afternoon or evening.