Extensive damage to the electricity network across the lower North Coast (including Greater Taree) and the Upper Hunter has slowed power restoration efforts today (Monday), according to Essential Energy's regional manager, Brendon Neyland.

Widespread damage occurred when a large storm front moved through the area on Sunday afternoon.

The damage included trees across powerlines, broken poles and pole cross-arms and lightning strikes to equipment.

Worst hit were Dungog, Stroud, Gloucester, Bulahdelah, Nabiac and surrounding areas up to and around Taree, including Wingham and the coastal strip.

As of 2.30pm Monday, around 7200 customers remain without power, down from a maximum of 36,000 at the height of the storms.

Essential Energy has called in additional crews from both inside and outside the region to assist local depots.

Mr Neyland said it was clear a large number of customers would remain without power tonight.

"Patrols are finding multiple areas of damage to some of our high voltage powerlines, which is slowing progress," Brendon said.

"Additionally, there is also considerable damage to the low voltage network including service lines and fuses that will need to be repaired before power to all individual premises can be restored."

"Our crews will continue to work as quickly as safety allows to restore supply."