Powerco was unable to confirm that the weather was the cause of all the outages, but said it was likely.
Watches and orange warnings were issued on Wednesday night for wind and rain in parts of inland Whanganui, Ruapehu and South Taranaki.
All watches and warnings for those areas were lifted on Thursday morning.
MetService meteorologist Michael Pawley said although the mean wind speed in Whanganui was about 45km/h, gusts were reaching up to 90km/h.
Pawley expected that thunderstorms would ease as the weather system moved east, but Whanganui was still in store for a cold and showery weekend.
Powerco said if people saw downed powerlines, they should stay at least 10m away from the lines and poles, and immediately call 111 or Powerco’s emergency number, 0800 27 27 27.
If customers experienced an outage, they were advised to report it by contacting their retailer or using the report an outage form on Powerco’s website.
Olivia Reid is a multimedia journalist based in Whanganui.