Developing Flood Event — Torrential rain continues to fall over Central Plateau this evening and shows no signs of easing soon says WeatherWatch.co.nz.
The rain set in overnight and has not eased for some areas through central parts of the North Island all day, however has started to ease in Northland and this evening Auckland and Taranaki.
Head weather analyst Philip Duncan says the bulk of the rain is falling central areas – and being the high point of the North Island this means significant run off to the north and south waterways. “If you think of the Central Plateau it’s a bit like the roof of your house – the rain will fall over it and then run down either side, in this case to the north or south. So we’re going to see significant runoff into both the Waikato River, flowing northwards into Waikato – and the Whanganui River, flowing southwards into Wanganui city”.
WeatherWatch.co.nz says both rivers will continue to rise over the next 12 to 36 hours and residents and farmers along those rivers should be monitoring local council websites for live data and information and special local Civil Defence messages.
“The high that last week worked for us by delivering frosty mornings and blue skies is today working against us by holding up this heavy rain over the North Island” says Mr Duncan.
The Wanganui District Council predicted the Whanganui River would rise to 12.5 metres at midnight, Newstalk ZB reported, and would reach the city by 10am tomorrow.
It could threaten the Kowhai Park stopbanks as well as homes on Anzac Parade.
Meanwhile Civil Defence Waikato warns that today’s expected rain could cause a once-in-20-year flood event.
“Today’s rain is expected to cause flooding of the Waipa River and catchments on the region’s west coast. Farmers are urged to keep up to date on water levels and move stock to higher ground if necessary. We’re not expecting any major disruption as a result of the rain, but people do need to be alert to the potential for flood plains to be inundated, general surface flooding and potential problems with road access due to slips” says Environment Waikato.
Meanwhile a secondary front is now racing up the West Coast bringing more heavy downpours to Hokitika, Westport and Greymouth. It’s expected to ease overnight and not cause too many issues.