Heavy rain warnings are in place across the South Island from Thursday evening into the weekend.
In Tasman up to 170 millimetres of rain was expected to fall west of Motueka in the 24 hours from 5pm on Friday.
In Buller, the warning was in place from 1pm Friday to 3pm Saturday, with up to 150mm of rain expected to fall in the ranges and up to 90mm about the coast.
In Westland, the heavy rain was expected to begin on Thursday night from Otira south, with up to 160 mm of rain expected to fall in the ranges and up to 80 mm around the coast.
A second period of heavy rain was likely on Saturday.
MetService said the heavy rain could case streams and rivers to rise rapidly.
"Surface flooding and slips are also possible and driving conditions may be hazardous."
The country "starts to dry" on Monday, Metservice said, with a short stint of fine weather "before the next round of rain reaches New Zealand".
The public was advised to keep up to date with the latest forecasts in case other areas were added to the heavy rain warnings.