Ms Pani said there were slow moving queues from Warkworth to the start of the Northern Gateway Toll Road at Orewa.
There was also delays south from Wellsford to the Wayby Road intersection, Ms Pani said.
Two crashes on the Southern Motorway near Takanini caused congestion earlier, and traffic has also been very heavy over the Bombay Hills on to State Highway 2 and at the State Highway 2 and State Highway 26 intersection in north Waikato.
Ms Pani said congestion could be avoided if people delayed their travel until later this afternoon.
Those people travelling north could also choose to use State Highway 16 between northwest Auckland and Wellsford, she said.
Ms Pani also reminded drivers of road works taking place at the Te Atatu interchange on the Northwestern Motorway and on the Auckland Harbour Bridge where two of the eight lanes were closed for re-sealing.
Earlier today northbound traffic was congested on State Highway 1 between Puhoi and Orewa north of Auckland, police said.
The traffic was reported to be bumper to bumper and was travelling very slowly between Puhoi and Hatfields Beach.
Police have urged motorists to be extra careful on the roads during the holiday period and be mindful of heavier traffic.
One person has already died and several others injured as a result of road collisions since the start of official the holiday road toll period.
Holiday road toll: First fatality
Last year's Christmas-New Year road toll was seven, from a total of 193 reported injury crashes. But the official holiday period was three days shorter than this year.
Yesterday a man who was driving a hired car south towards Tauranga died as a result of the collision. An elderly couple also involved in the crash remain in a serious condition in Tauranga Hospital.
The fatality in the Bay of Plenty came as seven people were injured after a campervan and a car crashed on the Athol Five Rivers Highway, between Queenstown and Invercargill, just after 4.15pm yesterday.
Two passengers from the car were taken to Dunedin Hospital with serious injuries, including burns.
On Tuesday a family of four were killed, following a crash between a car and a logging truck - just a day before the start of the official holiday road toll period.
The crash occurred about 1pm, after a north-bound vehicle on State Highway 1 pulled to the left-hand side of the road and attempted to complete a U-turn in front of a north-bound fully-laden logging truck, Northland road policing manager Murray Hodson said.
He said the crash was a result of driver error. Andy Li, 43, Catherine Li, 10, Xingwu Bian, 47 and Ximeng Bian, 8, all from Auckland, died as a result of the crash.
An eight-year-old boy - who had also been travelling in the car - was critically injured, and remained in Auckland's Starship Hospital in a stable condition.