Heavy fog this morning caused traffic disruptions on Auckland's roads and motorways, but did not interfere with flights.
Fog was still heavy over spaghetti junction on the motorway and there are still traffic delays in Auckland, said NZTA spokeswoman Sarah Azam.
"There's really reduced visibility so the message is obviously lights on and watch your following distances.
"And be patient, everybody's in the same boat."
Travel time to the city from Papakura was 90 minutes, Hobsonville was 49 and Oteha was 56.
As well as fog, the Papakura travel time could also be a combination of an earlier accident, Ms Azam said.
The New Zealand Transport Association and Auckland Transport tweeted to warn motorists of traffic delays and remember to put their lights on.
A crash just past Market Road on the Southern Motorway was blocking the right lane, NZTA tweeted just before 8am.
Long queues and heavy fog were reported at Oteha Valley Road around 7.40am, with drivers warned it could take over an hour to reach the city.
Earlier Dominion Road had to be closed briefly following a bus crash.
The city bound side of the Southern Motorway was also temporarily blocked following a crash.
Auckland Transport warned of ferry delays due to fog.