Northland emergency services were on stand-by last night after severe weather warnings forecast the region would be hit by extreme winds and heavy rain.
MetService said a very deep low was expected to bring damaging northwest gales gusting up to 130km/h across Auckland and Northland last night and this morning.
There was also a moderate risk of thunderstorms.
Forecasters warned winds of this strength could damage unsecure structures, trees and powerlines, and make driving conditions hazardous.
The entire country was battered by the weather system and the forecasted rain and gales, with areas such as Waikato and Auckland feeling the force of the storm yesterday afternoon.
"This is a significant weather event for the country, and people are advised to keep up to date with the latest forecasts," MetService said.
TopEnergy project delivery manager Geoff Smith said staff were rostered on around the clock to deal with any outages across the region.
"We get [weather warnings] throughout the year, and this one is being treated like all others. We may take extra precautions such as employing extra staff including tree cutters. We are pretty well covered," he said.
Mr Smith said fallen lines and tree damage would be the most likely things they would encounter. He advised anyone affected by power outages to call the fault-line where a regular update would be logged and available to customers.
Northland can expect showery weather tomorrow as the low trough hangs around just north of Cape Reinga, but a high pressure system is expected to shift over the region later in the day.
MetService warned showers may develop into heavy rain for the Far North later in the week.
The low weather system should have passed by Friday and weekend weather is forecast to be fine and calm.