LANCASTER – Be prepared for extreme heat for our region. A heat advisory is in effect today from 11 a.m. to 8 p.m. Heat index values of up to 105 degrees are expected. Hot temperatures and high humidity may cause heat-related illnesses. Drink plenty of fluids, stay out of the sun, and stay in air-conditioned areas. Check on elderly relatives and neighbors to make sure they are okay. Monitor people who work outside, exercise or play sports, ensuring frequent breaks. Know the signs and symptoms of heat exhaustion and heat stroke. Anyone overcome by heat should be moved to a cool location. Young children and pets should never be left unattended in vehicles under any circumstances as car interiors can reach lethal temperatures in a matter of minutes in hot weather. Also, be on the alert for the possibility of some strong storms that could cause flash flooding, hail, and localized damaging wind gusts.