Thousands of Far North homes, farms and businesses that lost power in Tuesday's storm are expected to have it restored today, Radio New Zealand reports.
But more than 4000 are expected to still be without electricity tonight and it's likely some may not be back on line until the weekend.
The storm brought hurricane-force winds that snapped concrete power poles and felled massive trees from Cape Reinga to Kaiwaka.
Top Energy said repair crews were in effect having to re-build parts of the network, though it was hoping to restore supply to about 7000 of its customers today.
In the Auckland region, just under 2000 Vector customers remained without power, down from almost 17,000 at the height of the storm.
MetService said further moderate or heavy rain is expected in northern and eastern parts of Northland and could lead to more flooding and slips in already sodden areas. Gale-force winds were still likely for much of Thursday but should be below warning levels.