Motorists encountered thick fog heading into the city centre from the North Shore just before 5am, as well as from west of the city on the Northwestern Motorway.
There are overhead signs warning motorists: "Reduced visibility. Take extra care."
Drivers coming from South Auckland can expect a hazy drive in also, with fog increasing nearer the city centre.
Several collisions have been reported around the city this morning, including a two-car crash at a notorious intersection in Onehunga.
Nobody was injured in the 7.40am crash at the corner of Victoria St and Church St but the westbound lane of Church St was blocked and both cars needed to be towed, a police spokeswoman said.
An earlier crash just before the Grafton overbridge is also slowing traffic into the city from the Southern motorway.
It was blocking the right lane, but had been cleared by 6.45am.
The Auckland Airport Operations Centre said at 7.30am that there was no fog at the airport and flights were not affected by it as a result.
WeatherWatch said the thick fog may linger longer this morning - potentially into the 11am hour, according to its NZ Fog Forecaster.
#Auckland: Thick #Fog this morning may linger longer, potentially into the 11am hour according to our new exclusive NZ Fog Forecaster. Please check airport/airline website for flight delays and cancellations.
— WeatherWatch.co.nz (@WeatherWatchNZ) July 24, 2019
SH1 SOUTHBOUND - CRASH - 6:40AM Due to a crash just prior to the Grafton Rd overbridge, the right southbound lane is BLOCKED. Expect delays and pass the scene with care. ^AA pic.twitter.com/fjsDCrz3m6
— Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) July 24, 2019
Good morning from Auckland 🌅
The sunrise amid sea fog makes for an exquisite view.
We've had a warm winter, but that doesn't have any direct bearing on next winter in the U.S. 😉 pic.twitter.com/UBfvIN04W0
The MetService says Aucklanders can expect a fine start to the day - save for the morning fog - before cloud increases in the afternoon with a few showers and easterly winds.
A high of 15C and overnight low of 9C is forecast for the City of Sails.
#Auckland - Good morning, thick #Fog may linger until late morning for some today. Drive safely. If flying please check with airline/airport websites for latest delays and cancellations.