More than 100 people evacuated in Tasman Region, over half a metre of rain falls in Takaka in past 48 hours, heavy rain shifts to North Island and Marlborough. 

More than 100 people had to be evacuated from their homes overnight as the heavy rain which prompted them to leave continues to drench the Tasman region.

A state of emergency was declared last night as swollen rivers and landslides cut off roads and towns, and heavy rains flooded homes.

Civil Defence said rain has continued overnight in the region, although at a slower rate.

More than 500mm has fallen near Takaka in the past 48 hours.

Two New Zealand Army unimogs have been brought in to help access residents stranded by floodwaters.

Heavy rain, torrential at times, is spreading into much of the northern and western side of the North Island and in Marlborough this morning possibly bringing more flooding, predicts WeatherWatch.co.nz.

The national weather news authority says there is now a high risk for surface flooding in Northland, Auckland, northern Waikato, Coromandel Peninsula, Manawatu, Horowhenua, Taranaki, Kapiti, Wellington and Marlborough.

WeatherWatch.co.nz says there is a moderate risk of isolated flash flooding within those regions and a moderate risk for slips and rockfalls.  It advises the public to stay away from small creeks, streams and flood drains across those regions and to avoid beach front cliffs around Auckland due to the high risk of rock falls.

The slow moving airmass is incredibly humid and has potential to create locally explosive downpours which can lead to flash flooding.

“Flash flooding is when a usually small stream, creek or drain turns into a raging torrent within minutes and can be deadly” says head weather analyst Philip Duncan.  “This is expected in isolated pockets right up the western and northern coastlines of both islands”.

Heavy rain eased in some parts of Nelson overnight but could return this morning.

WeatherWatch.co.nz says the heaviest rain will be in north western areas of both islands but most areas across New Zealand will receive rain at some point.  Farmers and gardeners will be mostly delighted with the rain.

“Despite the low being centred just off the Fiordland coastline the front connected to it has strong sub-tropical connections, which is why it’s so warm and humid across many parts of the country”.

The low will actually do a u-turn in the coming 24 hours and start to drift north east, crossing over the Auckland region while dying out over the weekend bringing showers, more rain but a slightly more refreshing change in wind direction.

– WeatherWatch.co.nz and nzherald.co.nz