...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING... * WHAT...The combination of high humidity and air temperatures around the century mark, will result in maximum heat index values between 105 and 109 degrees. * WHERE...Portions of north central and northwest Louisiana, southeast Oklahoma, south central and southwest Arkansas and east and northeast Texas. * WHEN...Today until 7 PM CDT. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses to occur.