* WHAT...Heat index values from 105 to 110 each afternoon and overnight lows from the mid 70s to lower 80s expected.
* WHERE...Portions of northwest and west central Arkansas and east central, northeast, and southeast Oklahoma.
* WHEN...Until 8 PM CDT Friday.
* IMPACTS...Heat related illnesses are possible especially impacting those not acclimated to the conditions or those performing strenuous activities.