* WHAT...Afternoon heat index values up to 105 expected. Overnight low temperatures between 73 and 78.
* WHERE...Portions of southwest Iowa and east central and southeast Nebraska.
* WHEN...Until 7 PM CDT Friday.
* IMPACTS...Hot temperatures and high humidity may cause heat illnesses. Several days of excessive heat will add to cumulative heat stress.
* ADDITIONAL DETAILS...The heat advisory may be extended or expanded as the prolonged heatwave continues.