While roadwork on several main highways leading in and out of Hawke's Bay are ongoing, requiring motorists to take extra care and attention, the "take care" advice is also being applied to central Napier.
With the 25th Geon Art Deco Weekend kicking off yesterday, the roads were expected to fill up with more and more older, potentially slower, cars.
"There will also be a greater concentration of out-of-town traffic," a New Zealand Transport Agency spokesman said.
"Extra patience and care will be required."
Motorists are also advised to be aware of a large number of road closures which will take place in the central city, as well as some stretches of Marine Parade, and to observe closure warnings and signs.
Cars found parked unlawfully inside the closed-off areas will be towed.
On the open roads, there are several maintenance sites on State Highway 2 north, between Whirinaki and Tutira, where there may be minor delays.
Delays are also expected on SH2 south, with work sites scattered at various spots between Napier and Dannevirke, while bridge work is being carried out intermittently on the Estuary Bridge at Westshore. Road maintenance is also under way at various sites on SH5, between Esk Valley and Te Pohue, and there are likely to be delays at the Mohaka Bridge, where speed restrictions and stop-go signalling is in place.