From the National Weather Service:
Hot and humid conditions will combine to produce maximum heat index values ranging from the mid 90s to around 100 Wednesday and Thursday.
Heat- Max heat indices of 95 to around 100 are likely Wednesday and Thursday between noon and 8pm both days for the entire area . Low temperatures will range mostly 75 80, which will not allow for much cooling off at night. Some relief is possible on Friday.
Impacts- There is an increased risk of heat related illness for vulnerable populations with this event.
A Heat Advisory is in effect for Wednesday. The heat advisory will probably need to be extended into Thursday as well.