Update: Northeast Pa. placed under a cold weather advisory until Sunday morning – dangerously cold wind chills

"Very cold wind chills as low as 15 to 25 degrees below expected," says the weather service. Understanding cold weather alertsCold weather advisory: Be Aware. A cold weather advisory is issued when seasonably cold air temperatures or wind chill values, but not extremely cold values, are expected or occurring. An extreme cold warning is issued when dangerously cold air temperatures or wind chill values are expected or occurring. An extreme cold watch is issued when dangerously cold air temperatures or wind chill values are possible.