Several South Island towns have been cut off and multiple flights have been cancelled as torrential rain lashes parts of the country.
High river levels combined with flooding, fallen trees and slips have largely halted travel through the regions, with access to Tākaka, Collingwood and Murchison blocked off in Tasman.
More than 820 people were evacuated from low-lying areas last night, with the majority spending the night in emergency shelters set up in Westport.
It comes as MetService announces an extension to the rare red warning in place through to 3am tomorrow, with more flooding likely.
Waka Kotahi NZTA is urging all motorists in the area to avoid unnecessary travel, particularly through Nelson and Marlborough, with more rain on its way in the coming hours.
A state of emergency has since been issued for Marlborough, with residents of the Lower Terrace in Renwick asked to evacuate their properties and stay with family or friends for the next 24 hours, Marlborough Deputy Mayor Nadine Taylor said today in a statement.
"Our crews are working as hard as they can but these slips and debris will take time to clean up and flood waters take time to subside," spokesperson Tresca Forrester said.
"Please do not drive if you do not have to or delay your journey until later today and check highways then."
For full details on road closures, check the NZTA website.
Meanwhile, at least four flights have been cancelled out of Nelson Airport as of lunchtime today, with a further two services inbound also grounded.
Some flights from Auckland to Whangārei, New Plymouth, Palmerston North, Blenheim and other centres have been cancelled.
There are significant delays on flights and some cancellations into and out of the capital today with high winds causing disruption.