New Zealand Transport Agency is urging drivers to plan before a safe summer road trip, as several accidents snarled Auckland traffic on Christmas Eve.

It warned that a combination of more cars on the road, tired drivers and people driving on unfamiliar roads can all add up.

NZTA encouraged everyone to check that their car was safe before heading off – and to avoid speeding, drive sober and to watch for signs of fatigue. Also to drive to the conditions, which could change quickly, and to check the weather forecast before leaving home.

As for where the traffic will be ...

There is expected to be a lot more congestion on December 26 – on both the North and the South Island.

Beginning from State Highway 1 in Northland’s Kawakawa, in the Bay of Islands area, it will be busy for an hour from 2pm to 3pm.

And from Kaipara Flats to Pukerito from 9.30am to 1.30pm.

It will also be busy on Auckland’s State Highway 1, from Manukau to Bombay, between 9am and 6pm.

The heaviest period will be from 10am to 11.30am.

And between Pūhoi and Wellsford from 9.30am to 4.30pm, with the heaviest period between 11am and 2.30pm.

In Waikato, it will be slow from Tīrau to Karapiro – once again – between 10am and 6pm.

On State Highway 2, from Pōkeno to Maramarua, it will be busy from 9am to 2pm.

And from 12pm to 1pm between Paeroa and Waihī.

In the Bay of Plenty, it will be busy from 10am to 3.30pm between Tauranga and Katikati on State Highway 2.

As well as on State Highway 29 in Kaimai, west of Tauranga, from 8am to 2.30pm.

In the Manawatū-Whanganui Region, it will be slow between Taihape and Waiouru from 10.30am to 4pm.

The heaviest period will be between 12pm and 3pm.

And from 9.30am to 5.30pm in Ōhau.

In the Wellington Region, it will be busy between Peka Peka and Ōtaki from 10am to 12.30pm, and from 4.30pm to 5.30pm.

In the South Island, it will be slow from 10am to 12pm on Canterbury’s State Highway 1 in Waipara, north of Christchurch.

From 1pm to 2.30pm in Kaikōura.

South of Christchurch, there will be traffic to Ashburton between 8am and 1.30pm.

And from 8am to 2.30pm on State Highway 1 in Timaru.

On State Highway 79 in Geraldine for a short period of time between 12pm and 1pm.

For even less time on State Highway 7 in Lewis Pass – between 12pm and 12.30pm.

And last, but not least, on State Highway 6 in Queenstown from 11am to 3pm.

-RNZ