Here's what authorities are advising Aucklanders after the West Auckland tornado and flash flooding.
Severe thunderstorm warnings and watches have now been lifted.
But more bad weather is predicted from midnight, with showers, which may become heavy, and winds reaching 100km/h.
There has been widespread surface flooding on roads and motorways throughout Auckland and motorists are urged to take care or stay off the roads if possible.
The NZ Transport Agency says it has re-opened State Highway 18 (the Hobsonville Motorway) after it was closed when a series of tornados swept through north-west Auckland this afternoon.
Auckland Airport said this evening all scheduled domestic and international flights were still experiencing delays due to "severe storm safety protocols" being in place.
A number of arriving flights were diverted to other airports.
Air New Zealand said it had cancelled 15 domestic services that were scheduled to depart Auckland and eight international departures scheduled through to the early evening have been rescheduled.
Passengers enquiring about individual flights should contact their airline or check the Auckland Airport website .
Public transport: Trains are operating as normal. Ferry services are continuing but the 5.30pm service to West Harbour is to be replaced by a bus.
Bus services are disrupted to Herald Island route 093 and Hobsonville Point routes 092 and 093. Route 130 is suspended. Some other bus services may be delayed.
Auckland Civil Defence is working with emergency services, and closely monitoring the situation in West Auckland where there are reports of fatalities and roof damage following a tornado around lunchtime.
Electricity is off in numerous parts of Auckland including Henderson, Greenhithe, Hobsonville, Riverhead, Meadowbank and St Johns. Vector is the contact point for more information. Vector says if you see lines down, please treat them as live and report the incident on 111.
Police have set up an operational base at Whenuapai near where the worst of the damage is reported.
About 150 homes have been displaced at Whenuapai and many have been deemed uninhabitable or are without power. Two hundred and fifty residents affected have been taken to Whenuapai Air Force Base where they will be looked after, and Auckland Council welfare staff have also gone to assist. Civil Defence is liaising with Whenuapai Airbase and will provide support as required.
The Ministry of Civil Defence and Emergency Management advises that as storms approach you should:
- Take shelter, preferably indoors away from windows;
- Avoid sheltering under trees, if outside;
- Move cars under cover or away from trees;
- Secure any loose objects around your property;
- Check that drains and gutters are clear;
- Be ready to slow down or stop, if driving.
During and after the storm, you should also:
- Beware of fallen trees and power lines;
- Avoid streams and drains as you may be swept away in flash flooding.
Westfield WestCity - Henderson is open and trading. The centre says whilst a handful of stores have been closed while safety checks are carried out following some water damage, it is fortunate that the centre and other amenities and car parks have not been impacted.