Northbound travellers at Hexham near Newcastle face delays up to 30 minutes between 9am and 11am from December 26 to 30.
Southbound traffic at Nowra and Batemans Bay could be delayed 20-45 minutes between 11am and 6pm from December 26 to 29. Traffic northbound into Ulladulla and around Jervis Bay is predicted to be busiest from 11am to 1pm between December 26 and 31.
Between December 18 and 23, Coffs Harbour and the Hexham Bridge are expected to be the worst choke points when travelling north.
Generally, travellers heading north or west from Sydney should avoid leaving the city between 9am and 3pm, and also try to time their return outside peak hours.
For those going south, it’s best to leave before 11am or after 6pm and on the return aim to avoid the 9am-3pm window.
NRMA spokesman Peter Khoury said he expects “considerable delays” on major routes out of Sydney but said ongoing road upgrades are making a difference.
“The Pacific Highway has demonstrably gotten better year-on-year with the improvements,” he said. “That will make the whole experience of heading up the North Coast different and definitely safer. It was Australia’s worst road.”
While some people might be tempted to start early to avoid delays, Mr Khoury advised against starting a trip in the middle of the night.
“Don’t do that. Your body clock is telling itself you’re meant to be asleep. It’s one of the quickest ways to get fatigued,” he said.
This holiday period marks the first since the NorthConnex tunnel opened, enabling northbound drivers to bypass suburban Sydney.
“Historically Pennant Hills Road has been a nightmare for people going away on holidays so we’re hoping it’ll be relieved,” Mr Khoury said.
However, the extra cost of the tunnel adds to the toll burden for motorists using the M7, M2 and NorthConnex. A journey from the Southern Highlands to the Central Coast costs $20.19 one way.
University of Sydney transport expert Geoffrey Clifton said despite substantial investment the road network is “never perfect”.
“You clear one pinch point and that moves the congestion further down the road. It’s an ongoing process,” he said.
Dr Clifton said the next step is diversifying the network to increase resilience.
“You’ve got one good highway north [but] what happens if the Pacific Highway is cut off at the Central Coast because of a bushfire nearby? There’s no easy way around that.”
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Josh Dye is a news reporter with The Sydney Morning Herald.