PITTSBURGH — (WPXI) – Temperatures quickly dropped into the single digits Friday morning and wind chills will head below zero. Wind chills will stay below zero into Christmas day with winds gusting to 50 mph at times Friday night and Saturday. A Wind Chill Watch has been issued for the entire area for Friday night and Saturday as wind chills will approach -20 degrees. Most areas will only see one to three inches of snow total through the day, but with frozen water underneath the snow layer, it will make for very dangerous travel conditions. There are power outages. As of 10:30 am, West Penn Power was reporting more than 900 customers without power countywide. The temperature was near 40-degrees at 3 a.m but quickly dropped causing numerous problems. There were numerous reports of trees and wires down. A tractor-trailer jack-knifed and went off of Interstate 70 westbound just past the Taylorstown exit. The driver was not injured. there were other reports of accidents and fire crews were called out to a reported structure fire in the 600-block of Speers Avenue in Speers Borough just before 9 a.m. Tune to WJPA 95.3FM/1450AM for the very latest.