'Ugly' storm to bring rain, gales to Waikato

02:29, Sep 24 2013

A "beast" of a sub-tropical storm is bearing down on Waikato today, bringing with it 130kmh winds. 

A high wind warning for the Coromandel was today extended to Eastern Waikato in general, especially in the lee of the Kaimai Range, meaning residents there also need to be on the alert, says Waikato Civil Defence.

Forecasters are predicting heavy rain, gale-force winds and huge swells will batter the region from the east, making road and ocean conditions treacherous.

The rapidly deepening low started as an area of moist tropical air northeast of the North Island but an upper trough had wound it up into a "pretty mean beast", MetService meteorologist Daniel Corbett said. The "significant" storm was unusual for this time of year and it was "pretty ugly". "For many of those eastern areas, damaging winds will be getting up to 130kmh for places such as Coromandel Peninsula." Some places could receive in excess of 100 millimetres of rain and the orientation of the winds and swell could mean flooding both inland and on the coast, Mr Corbett said.

A storm warning is in force for the Bay of Plenty and Coromandel, with sea swells predicted to reach 4 metres today.

The severe weather watch extends to Waikato, Waitomo, Bay of Plenty, Rotorua, Taumarunui, Taupo and Auckland.


Heavy rain and potentially severe gale southeasterlies are expected to hit those areas today. Mr Corbett said every storm has its own character.

"They're all bad in their own way but this one will be for damaging winds, flooding and coastal effects. It's going to be a pretty nasty 24 to 48 hours but Friday is the day we can put a smiley face next to and catch our breath."

Waikato Civil Defence is urging Coromandel residents to be on alert.

Wind gusts of 130kmh are expected from this afternoon before easing about midnight as the system moves inland from the east coast. Residents should secure loose items, take care on the roads - especially in high-sided vehicles - and be aware of the potential for trees and debris to be blown across the road.

Heavy rain of between 100mm and 120mm is expected on the peninsula from late morning before easing overnight. Mr Corbett said this kind of low usually arrived in the cyclone season, from January to March. It would be "loaded" with water because tropical air could carry so much moisture.

It comes after torrential rain at the weekend which caused slips and closed roads around the region.

Ruapehu emergency management officer Nick Watson said slips had closed the Ruatiti, Mangatarata and Waitaanga roads while floods shut down the Ongarue, Tokirima and Ohura roads.

The storm may cause surface flooding on the Coromandel Peninsula and place further pressure on river systems that rose after the weekend rainfall.

River systems across the region are also under pressure and could swell further today and tonight. Rivers are particularly high in the western Waikato.

Waikato Civil Defence has also been alerted to the potential for abnormally high seas due to the combination of low atmospheric pressure, strong easterly winds and a heavy ocean swell.

Low-lying coastal land exposed to the east is expected to be most at risk and residents are advised take precautions.