* WHAT...For the first Heat Advisory, heat index values up to 108. For the second Heat Advisory, heat index values up to 107 expected.
* WHERE...Portions of southwest Oklahoma and northern Texas.
* WHEN...For the first Heat Advisory, until 8 PM CDT this evening. For the second Heat Advisory, from 1 PM to 8 PM CDT Thursday.
* IMPACTS...Hot temperatures and high humidity may cause heat illnesses.