Drink plenty of fluids, stay out of the sun, and stay in an air-conditioned room. Young children and pets should never be left unattended in vehicles under any circumstances. This is especially true during hot weather when car interiors can reach lethal temperatures in a matter of minutes. LOOK BEFORE YOU LOCK. Monitor the latest forecasts and warnings for updates on this situation.

* WHAT...Oppressive heat with afternoon heat indices near 100 degrees. * WHERE...The Middle Susquehanna Valley and the valleys of south central Pennsylvania. * WHEN...Until 8 PM EDT this evening. * IMPACTS...High temperatures and humidity may cause heat illnesses.