Local civil defence and emergency authorities in New Zealand reported earlier today that torrential rain had caused localised flooding in parts of Nelson city and Tasman district. In some areas, over 50cm of rain has fallen in the last 2 days.
The flooding comes during a period of severe weather and storms across the country. Meteorological Service of New Zealand reported over 180 lightning strikes, three of which struck houses, in the Central Otago district of the South Island. Strong waves and rough seas also caused significant problems in the Auckland area.
Nelson Tasman Civil Defence and Emergency Management said in a statement earlier today that the rain had caused extensive surface flooding across the region.
Significant rainfall accumulated in the region’s rivers with the Wairoa River reaching 25 year flood level, Anatoki River reaching 10 year flood level, and the Maitai reaching annual flood level.
Significant flooding was reported in Golden Bay as a result of the overflowing Anatoki. The flooding Wairoa River caused extensive surface flooding around the Brightwater area. Several roads were closed. Flooding was also reported in Ferntown, Waitapu Splash, Upper Takaka and Lindsay’s Bridge.
Meteorological Service of New Zealand recorded 67.8 mm of rain at Nelson airport yesterday, 17 February 2016. The average rainfall total for a typical February is 46 mm. However, civil defence reports say that in localised areas, the rainfall was far more extreme.
Nelson Tasman Civil Defence said that:
“parts of Nelson Tasman were drenched by more than half a metre of rain over the past 48 hours. 528 mm was recorded at the Paradise raingauge in the hills behind Takaka”.
There were no reports of evacuations or injuries. Civil defence authorities are expecting further reports of flood damage now that the worst of the weather has passed and people are better able to assess the situation.
Heavy Rain Warnings 150 mm to 250 mm Possible for Parts of South island
The heavy rain warnings for the Nelson area have since been lifted. However, earlier today a Meteorological Service severe weather warning was in place for the the West Coast of the South Island and in Bay of Plenty and Rotorua. Met Service said;
“A complex low over the Tasman Sea is expected to move east across the South Island today and early tomorrow, bringing heavy rain to the West Coast of the South Island and strong northwesterly winds over the South Island and lower North Island from this afternoon to Friday.
“Heavy rain and thunderstorms are expected about Fiordland, Westland and Buller through to Friday morning, where another 150-250mm could accumulate on top of what has already fallen on the ranges of Westland. Heavy rain is forecast to continue in Bay of Plenty through Friday afternoon, where 150mm could accumulate over a 30 hour period.”