Central Electric Cooperative is continuing to restore power to its members who have been without electricity since Thursday's winter storm.

As of 5 p.m. Monday, fewer than 4,400 customers were waiting to be restored, down from 7,600 Sunday evening, according to Ken Maleski, manager of communications and public relations for the Parker-based cooperative.

"The largest concentration is in Butler County, spread out all over Butler County," Maleski said late Monday afternoon.

Earlier in the day, Maleski said additional crews arrived and "we expect to make a pretty big dent today, especially in the substations in Venango County."

Central Electric's territory includes Venango, Clarion, Forest, Butler, Armstrong and Mercer counties.

Maleski said Central Electric's Venango County customers suffering power outages were mostly in the areas of Irwin and Clinton townships.

"We have made significant progress today and plan to do so Tuesday, but given the severity of the damage, total restoration of all members is on a day-to-day basis," Maleski said.

Outages were mostly caused by tree damage, given the sudden accumulation of heavy snow and ice Thursday. Maleski said downed trees caused numerous broken utility poles, which take four to five hours each to repair or replace.

Crews are required to check every section of line to ensure that it is safe to re-supply power.

"Before we re-energize a line, we want to make sure we have no downed wires on anybody's property, so that nobody gets injured," Maleski said.

Another reason for the delay in full restoration, Maleski said, was a supplier's loss of power to nine substations, which weren't reactivated until Sunday evening.

While Maleski made no promises on when all customers would be restored to service, crews continue to work around the clock with tree-trimming contractors attached to each crew.

Central Electric released a list of the following warming centers available in Butler County:

Herman fire hall at 789 Herman Road in Butler, Clay Township municipal building at 1115 Euclid School Road in Butler, Harrisville fire hall at 313 East Mercer St. in Harrisville and Bruin fire hall at 100 Firehouse Drive in Bruin.