Severe wet weather coupled with rising tides had closed roads and seen sandbagging in the upper South Island on Monday night.
A section of State Highway Six between Nelson and Blenheim is closed with slips and water on the road, especially around Pelorus Bridge.
Several vehicles have been stranded by rising waters but all drivers have been assisted by either emergency services or farmers.
In the west, sandbagging has been underway on the main street of Takaka in Golden bay as intense rain continues.
Takaka has been one of the first places to feel the brunt of the low heading in off the Tasman Sea.
Heavy rain and strong winds forced at least one local school to
close early on Monday because of fears about slips and flooding on
the rural school bus routes.
More than 200 millimetres has fallen in the region over the past
two days making driving treacherous.
Heavy rain has fallen in the Westland and Nelson ranges.
People have been advised to watch for rising streams and rivers and surface flooding, especially in Westland, Nelson and northern Marlborough.
Conditions are expected to improve on Tuesday.
By midnight, rain had eased in the Nelson area, with the Maitai River level receding after earlier fears of possible flooding.
A Council spokesman says Maitai Valley Road will remain closed for some time, as will Avon Terrace.
Civil Defence staff will monitor the situation throughout the night.
Police in the Nelson/Blenheim/West Coast area say many roads remain flooded, and debris from trees and rocks is making driving hazardous.
Extreme care is needed while driving anywhere in that region overnight.
Until the waters recede, State Highway Six will remain closed.
Heavy Rain Warning
Areas affected: Westland, Buller, Nelson, Marlborough Sounds, Richmond ranges, headwaters of the Otago and Canterbury lakes and rivers from Lake Wanaka northwards, Mt Taranaki to Mt Ruapehu and eastern ranges of Bay of Plenty.
Strong wind warning
Areas affected: Outer Marlborough Sounds and also the south coast and higher hill tops of Wellington and Exposed areas in Wairarapa.
