The Tasman District Council is asking people to stay off the roads as the storm battering the country hits the top of the South Island.
The council said a number of roads were already closed across the district, and it was likely that there would be more to come.
Mārahau was currently inaccessible as Riwaka-Sandy Bay Road and Kaiteriteri-Sandy Bay Road are closed due to flooding and rockfall.
MetService has orange heavy rain warnings in place for Tasman northwest of Motueka, the Richmond and Bryant ranges, and the Rai Valley until this afternoon.
Meanwhile, fallen trees have been creating hazards on state highways across the central South Island.
NZ Transport Agency Waka Kotahi (NZTA) has been alerted to several instances since last night where trees were reported to be at least partially blocking highways in Canterbury or on the West Coast. Contractors have been dispatched to clear the trees where required.
Road users are reminded to continue to travel with care while heavy rain and strong winds persist.
Further north, rain was starting to clear out from Northland this morning after it got a battering overnight.
MetService meteorologist Heather Keats told RNZ that Kaitaia, one of the worst-hit regions in Northland, had had more than two and a-half months' worth of rain since Wednesday, while Kerikeri had had one and a-half months' of rain in the same period.
They were able to start returning to their homes by early on Friday afternoon.
Emergency services had also rescued people from a series of flooded vehicles, prompting police to make a special plea for people to heed road closures.
Many roads around the district remain closed, and authorities continue to urge people to stay home and avoid non-essential travel.
While there is some respite to come over the weekend, flood-weary Northlanders are being warned more rain could be on the way within days.
MetService meteorologist Mmathapelo Makgabutlane told RNZ's Midday Report that storm-affected parts of the country would get a chance to dry out tomorrow and early Sunday.
"But then by the latter part of Sunday into Monday we have another low-pressure system that approaches and brings another bout of rain to much of the country," she says.
Makgabutlane says the areas most likely to experience downpours from those thunderstorms will be Northland, the central North Island and the west coast of the South Island.
