Up to 35,000 Aucklanders remain without power and hot water - and Vector warns some customers may have no electricity till Saturday.
Vector says more wind and rain forecast for Auckland tonight could delay the reconnection work.
Vector's outage response crews have restored power to more than half of those customers who were experiencing an outage last night, but more than 690 faults, power outages, and reports of damage on the network still exist throughout the region.
The electricity and gas distribution company said it expects it may take 48 hours to restore power, but the number of customers without power and the number of jobs its staff need to respond to is subject to change considering the possibility of bad weather due to hit Auckland from 5pm tonight.
More than 40 suburbs are still affected by power outages.
"Power is expected to be restored to 80% of that suburb by midnight tonight," Vector said.
"If a customer is experiencing an outage in these suburbs, power is unlikely to be restored before end of day tomorrow or even longer. Those customers should make contingency plans, if they haven't already done so."
A John St, Ponsonby, resident is concerned a tree that fell onto a neighbouring house has not yet been removed.
Narelle Mullins has had no power since Tuesday night.
She was concerned nothing could be done to restore power until the tree, which had fallen into lines, was removed.
"My worry is that the removal of the tree has to be actioned by an authority - and that may take a long time."
MetService meteorologist Stephen Glassey said temperatures today got down to 7.5C at 5.30am.
More strong winds are forecast for the North Island tonight, and a severe thunderstorm watch is in place for Northland, Auckland and Waikato.
Meanwhile, this week's windy weather has added to a busy start to the year for insurance companies.
Insurance Council chief executive Tim Grafton said insurers have already paid out $93 million this year, after a string of major storms.
He said it's too early to know the full cost of the latest storm, but a lot of damage has been reported.
Grafton said people should get emergency work done first, but talk to their insurance company before doing more extensive repairs.
Areas with outages due to be fixed by midnight tonight
• Albany Heights
• Albany North
• Arkles Bay
• Beach Haven
• Browns Bay
• Campbells Bay
• Castor Bay
• Crown Hill
• Fairview Heights
• Forrest Hill
• Long Bay
• Lucas Heights
• Mairangi Bay
• Northcote Point
• Northcote West
• Red Beach
• Snells Beach
• Stanmore Bay
• Te Atatu Peninsula
• Te Atatu South
• Te Hana
• Tindalls Beach
• Torbay Heights
• Unsworth Heights
• Wairau Park
• Western Heights
Areas with outages unlikely to be restored in the next 24 hours
• Bethells Beach
• Dairy Flat
• Dome Forest
• Dome Valley
• Glen Eden
• Green Bay
• Henderson Valley
• Kaipara Flats
• Massey North
• Mt Roskill
• New Lynn
• New Lynn West
• South Head
• Titirangi North
• Titirangi South
Power restoration process
Vector restores power in the following order:
• Network feeders and substations that supply power to large groups of homes or buildings.
• Critical infrastructure and buildings like hospitals, water and sewage plants, and airports.
• Large commercial buildings and industrial plants.
• Residential and individual homes.
• Streetlights and hot water pilot lines.
Vector's advice during ongoing outages
• Stay well clear of fallen power lines or damaged electrical equipment and treat them as live at all times.
• Avoid possible damage to electrical appliances (in the unlikely event there is a power surge when the power is restored) by switching off appliances at the wall.
• Where possible, make plans to stay with friends and family who have power, or make alternative accommodation arrangements.
• Keep a torch and spare batteries handy and ensure you have at least one telephone that does not rely on electricity to operate.
• Ensure an alternative fuel is always available for cooking (e.g. gas for BBQ).