* WHAT...For the Heat Advisory, heat index values up to 107 expected. For the Extreme Heat Warning, dangerously hot conditions with heat index values up to 111 expected.
* WHERE...Portions of west central Arkansas and east central, northeast, and southeast Oklahoma.
* WHEN...For the Heat Advisory, until 8 PM CDT this evening. For the Extreme Heat Warning, from noon to 8 PM CDT Tuesday.
* IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events. Heat related illnesses are possible especially impacting those not acclimated to the conditions or those performing strenuous activities.