* WHAT...For the Extreme Heat Warning, dangerously hot conditions with heat index values 110 to 115 degrees expected. For the Heat Advisory, heat index values of 105 to 110 degrees expected.
* WHERE...Portions of central, northern, and northwest Oklahoma.
* WHEN...For the Extreme Heat Warning, until 9 PM CDT this evening. For the Heat Advisory, from 11 AM to 9 PM CDT Sunday.
* IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events. Hot temperatures and high humidity may cause heat illnesses.