Holidaymakers should expect delays as they make their last-minute treks to New Year's Eve hotspots.
Motorists travelling on SH1 at Waipu have faced lengthy delays all afternoon after three separate crashes earlier today.
The crashes, which all happened within about half an hour of each other, and at least eight people were injured in the crashes, one critically. All were taken to Northland Base Hospital, St John said.
NZTA said all the crash sites had been cleared shortly before midday. However, according to the agency's holiday hotspots map, the road would still be congested until about 6pm.
The route will be busy again through Warkworth for most of tomorrow because of the Rodeo at A&P Showgrounds. NZTA warned travellers using this stretch of State Highway 1 to "allow extra time for travel".
Traffic on State Highway 1 south of Auckland is said to be free flowing now after peaking about lunchtime today.
However, Aucklanders travelling to the Coromandel or Tauranga probably won't be so lucky. NZTA predicted State Highway 2 would still be busy at Maramarua until about 5pm and between Paeroa and Tauranga until about 6.30pm.
NZTA said it State Highway 2 would be congested in the opposite direction tomorrow. The worst times to travel west between Tauranga and Paeroa would be between 12pm and 4.30pm.
Traffic would start builiding at Maramarua from 1pm tomorrow and the road will continue to be congested for most of the evening.
Wellingtonians escaping the capital on State Highway 2 should start to see traffic easing at Rimutaka Hill from about 5pm.
But the section of State Highway 1 connecting to the capital to Waikanae was expected to be busy in both directions until at least 5.30pm.
Traffic should start easing on State Highway 1 between Blenheim and Nelson eastbound about 4pm and westbound traffic should start easing about half an hour later.
Northbound travellers on State Highway 1 in Canterbury should get a clear run through Waipara from about 4pm. The road should also be flowing well between Ashburton and Christchurch.
There have been no fatal crashes to date today. The holiday road toll remains at 14 this evening after a person was killed in a single-car crash in Northland last night.
Heaviest traffic times
State Highway 1, south of Auckland (Takanini)
Northbound
Jan 3: 12.30pm-4.30pm
Jan 4: 1pm-4pm
State Highway 1, north of Auckland (between Puhoi and Wellsford)
Northbound
Dec 31: 11.3am-3.30pm
Jan 4: 12pm-1.30pm
Southbound
Jan 1: 10am -6pm
Jan 2: 10.30am-8pm
Jan 3: 11am-5pm
Jan 4: 11am-1.30pm
State Highway 2, toward Coromandel, Tauranga (Maramarua)
Eastbound
Dec 31: 11.3am-3.30pm
Jan 4: 12pm-1.30pm
Westbound
Jan 1: 1pm-7pm
Jan 2: 11am-7.30pm
Jan 3:12pm-6.30pm
Jan 4: 12.30pm-3pm
State Highway 1, north of Wellington (Kapiti Coast)
Southbound
Jan 1: 3pm-4pm
Jan 2: 11am-8pm
Jan 3: 11am-7.30pm
Jan 4: 12pm-6pm
Northbound
Dec 31: 9.30am-4pm
Jan 1: 11am-3pm
Jan 2: 10am-3pm
Jan 3: 10am-3.30pm
Jan 4: 10am-12.30pm
State Highway 2, north of Wellington (Rimutaka Hill)
Northbound
Jan 2: 9am-12.30pm
Southbound
Jan 2: 3pm-7pm
Jan 3: 4pm-5.30pm
Source: NZTA