* WHAT...For the first Heat Advisory, heat index values up to 106 expected. For the second Heat Advisory, heat index values up to 108 expected. * WHERE...In Arkansas, Southern Crawford, Central and Southern Franklin, and North and Central Sebastian Counties. In Oklahoma, Central and Southern Sequoyah, Muskogee, Okmulgee, Tulsa, Wagoner, Haskell, McIntosh, Northern Le Flore, and Pittsburg Counties. * WHEN...For the first Heat Advisory, until 8 PM CDT this evening. For the second Heat Advisory, from 1 PM to 8 PM CDT Saturday. * IMPACTS...Heat related illnesses are possible especially impacting those not acclimated to the conditions or those performing strenuous activities.