Fog restrictions have been lifted at Auckland Airport for the second time today after nearly 50 flights were cancelled or delayed.
Thick fog has caused havoc to travel across the city this morning, disrupting travel in the air, on the water and across the motorway network.
Auckland Airport said 24 flights across New Zealand had been cancelled and another 22 delayed when fog rolled in again.
Fog restrictions were lifted at Auckland Airport just before 7.30am after 25 flights were delayed and cancelled but reimposed just after 8.40am.
They were lifted for a second time at 9.17am.
A Qantas flight from Melbourne, earlier diverted to Wellington, has now landed in Auckland.
Motorists are being warned to take care as the murky conditions cloak the city's streets and motorways, drastically reducing visibility.
The Sky Tower had disappeared from the skyline and Niwa said people could see no further than 100m in some parts of the city.
Ferry services have also been disrupted and Auckland Transport warned people to expect delays heading to work this morning.
A truck breakdown on the Newmarket Viaduct led to an 11km queue for motorists heading to work in the murky conditions.
Auckland Airport warned passengers to expect delays and cancellations this morning.
It advised those flying to check the airport website for latest arrival and departure updates.
This morning harbour ferry services were cancelled and delayed by the thick fog.
Auckland Transport said the 7.20am sailing from Pine Harbour would be replaced by bus and cancelled the 8am service from Auckland.
A 7.30am sailing from Half Moon Bay to downtown Auckland had been delayed by 20 minutes.