* WHAT...Dangerously hot and humid conditions with multiple days of heat index values of 100 to 110 expected, along with nighttime lows not falling below the mid to upper 70s.
* WHERE...Portions of northwest and west central Illinois, east central and southeast Iowa, and northeast Missouri.
* WHEN...Until 10 PM CDT Wednesday.
* IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events.
* ADDITIONAL DETAILS...The extreme heat may persist through late week, but thunderstorms and associated clouds may interrupt the heat at times Thursday and Friday.