Warning to prepare for heavy rain, gales and storm surges when Gita reaches NZ

Friday, 16 February 2018

The MetService gives its forecast ahead of the arrival of what is left of Tropical Cyclone Gita.

The MetService is warning Kiwis to be prepared ahead of ex-Tropical Cyclone Gita hitting the country early next week, when it is expected to bring severe gales, storm surges and heavy rain.

The Fiji Meteorological Service said on Friday Gita had weakened to a category 3 storm and was about 470km west-southwest of Conway Reef by the early afternoon. It was moving west about 24kmh, and expected to pass to the south of Vanuatu and New Caledonia overnight Friday.

Despite Cyclone Gita's widespread destruction, many Tongan families are simply feeling lucky to be alive and together.

'There remains uncertainty with regards to the speed and track of Gita, but the passage of this system across New Zealand on Tuesday and Wednesday is likely to bring a period of highly impactful severe weather,' MetService said on Friday night.

'There is high confidence of severe gales and heavy rain spreading across central and northern New Zealand on Tuesday and Wednesday. In addition, winds associated with Gita are likely to cause large waves to affect some coastal places, and the expected storm surge allow run-up of waves in some low-lying coastal places, particularly at high tide.'

The expected track of Tropical Cyclone Gita for the next couple of days, issued by the Fiji Meteorological Service just after 2am Friday (NZT).

The MetService national weather forecast for the weekend.

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The Vanuatu Meteorology & Geo-Hazards Departments said heavy rain and strong winds were expected over the country's most southerly islands during Friday. In New Caledonia, heavy rain and gusts to 130kmh were forecast overnight Friday for the Isle of Pines, Mare and on the southern half of the main island of Grand Terre. Conditions were forecast to improve on Saturday afternoon.

MetService meteorologist Claire Flynn said Gita's track appeared to have moved a bit closer to New Caledonia than had been thought before.

Tonga rebuilds after Cyclone Gita - Koro Vaka'uta.

Model projections of the track Gita will take in the next five or six days, using ECWMF track data.

'The eye is looking like it will go south of New Caledonia, however the closer you get to the eye of a cyclone, the stronger the winds will be,' she said.

The change in Gita's forecast track for the next couple of days didn't change too much in terms of the thinking of how the cyclone was going to affect New Zealand.

'It's got that much further to go before it gets here. At this stage, essentially we're just saying, yes it's coming to New Zealand, most likely looking like Tuesday, and most likely looking like it will cross the North Island or central New Zealand.'

MetService meteorologist Lisa Murray said there was considerable uncertainty about Gita's impact on New Zealand.

'When you look at the ensemble approach, there's a very broad spectrum of what could happen,' she said.

'There is definitely going to be severe gales at some point around New Zealand. There will definitely be heavy rainfall as well.'

People should use settled weather expected for much of the country this weekend to do what they could to prepare for the stormy start to next week.

'We have a relatively benign weekend weatherwise, apart from some rain on the West Coast through to tomorrow afternoon,' Murray said.

'If you are in the top two-thirds of the country, it's a really good idea to make sure anything that could potentially in really strong winds become some sort of missile should definitely be put away. People should make sure drains and gutters are clear.'

Gita was expected to transition from a tropical cyclone into a mid-latitude low around the 35th latitude south, which was likely to happen mid-afternoon Saturday. There was no record of a named tropical cyclone crossing the land of New Zealand.

'Around a tropical cyclone, the strongest winds and heaviest rain are really near the centre of the cyclone,' Murray said.

'As it transitions from a tropical cyclone into a mid-latitude low that area of strong winds spreads out, and also the band of rain, so the amount of places that could be affected by strong winds and rain actually increases,' she said.

'Although this system won't be a tropical cyclone, it still has the potential to be a very dangerous low for New Zealand,' she said.

'Most of the big impact storms we've had through history have come from these ex-tropical cyclones or tropical lows.'