People must keep well away from any power lines brought down by the severe weather, Mr Marsh said.
"People need to keep themselves and their children well clear of any damaged network equipment and call emergency services immediately if they see a downed power line."
Trees growing close to overhead lines were a major contributor to power cuts during severe weather, he said.
"In many cases the people who plant trees and allow them to grow into our lines are subsequently affected, along with their neighbours."
Gale force winds gusting over 100km/h knocked over power lines, lifted roofs and brought down trees and garden sheds in Wanganui yesterday.
The wind brought down power lines in Brunswick Rd, and lifted part of the roofs from the BP service station on Taupo Quay, Carters and Chronicle Glass. The Fire Service reported several roofs detaching from houses and a few sheds being blown over.
Power was out for much of the day in parts of Wanganui, Westmere, Fordell, Hunterville, Ratana, Marton, Ohingaiti, Whangaehu, and Turakina Valley.
Conditions are expected to ease today, with MetService forecasting morning showers and easing winds.