LANCASTER – A heat advisory for our region has now been extended until Saturday at 8 p.m. Heat index values of up to 100 degrees are expected. If you must be outside, wear light colored clothing, drink plenty of water to stay hydrated, and take frequent breaks. Hot temperatures and high humidity may cause heat illnesses. Know the signs and symptoms of heat exhaustion and heat stroke. Persons can review heat safety and preparedness information at the website: The heat may be life-threatening to the elderly and those in poor health, particularly due to prolonged exposure without air conditioning. Check on elderly relatives and neighbors to make sure they are kept cool and comfortable. Persons can locate area cooling centers by clicking on the weather banner below..