Traffic is easing for drivers trying to get onto State Highway 1 from Mangatarata but there were still delays, NZTA says.
Westbound drivers on State Highway 2 were hit with queues before 5pm today - and at 6.30pm it looked like the back-up was starting to slightly clear.
"Congestion westbound on SH2 from Mangatarata to the intersection with SH1 has eased slightly, still delays in area," NZTA tweeted.
There was also spots of congestion on State Highway 25 with holidaymakers heading home from the Coromandel, the agency said.
"SH25 bits of heavy traffic showing at various points along Coromandel. Nothing major, but expect minor delays in patches," NZTA tweeted.
There was a trail of vehicles stuck in traffic from Drury to Takanini, with northbound congested patches also showing up at Rangiriri, Huntly and Cambridge, just after 5pm.
And in the Wellington region, things had not got too dire, NZTA said.
"A short queue for traffic heading southbound into Otaki, but seems to be flowing okay at this stage," the agency tweeted.
Earlier, traffic was becoming heavy near Huntly as motorists headed north, NZTA tweeted.
"Traffic is building northbound in and around Huntly. Please be patient and take breaks if needed. #DontDriveHangry," the agency said.
Wellington commuters were also experiencing delays as early as 1.30pm, it said.
"Holiday traffic starting to head back into Wellington, there is congestion S-Bnd on the Mana Esplanade, expect delays & take extra care," NZTA tweeted.
NZTA Wellington regional performance manager Mark Owen said traffic could add hours to drivers' journeys home.
Significant traffic was expected for commuters coming in to Wellington until about 5.30pm, he said.
The heaviest traffic was expected to be between 1pm and 6pm today.
"There was quite major congestion heading out on Friday and obviously all those people are going to be coming back probably this afternoon ... I think it added about an extra two hours to people's journey as they were heading out.
"It really depends on how many people go away, the weather and all those sorts of factors. It's hard to predict coming back in because the constrictions are different but I think if people can certainly avoid travelling mid to late afternoon, it drops away pretty quickly."
He said there were already reports of heavy traffic coming into Auckland from the south around Huntly as well as from the north - and the queues were expected to build over the next three hours.
"Obviously a lot of people left on Friday and Saturday for the long weekend away and all those people are now heading back into the big city," Mr Owen said.
Drivers should try to delay travel until this evening if possible but, if not, try to stay calm if they found themselves stuck in traffic, he said.
Some passing lanes would be closed in order to keep a single line of cars moving forward in hotspots.
"I really stress that we want people to have patience, there's a lot of people just like them out on the road trying to get home again.
"We just ask that they relax, drive to the conditions depending on the weather, and allow that extra bit of following distance, and not panic and try and get ahead."
