With cyclone force winds as high as 213km/h striking Auckland overnight, questions are being asked about whether forecasters and authorities were caught unprepared.
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Source: 1 NEWS
The wild weather cut power to more than 100,000 homes in the Auckland region, disrupted traffic lights, rail services and airline flights and caused widespread damage.
The extent of the damage caught many by surprise.
But while forecasters had expected damaging winds and power cuts, the ferocity of the gales and their direct hit on Auckland did catch authorities by surprise, WeatherWatch says.
A downed power line in Auckland after gale-force winds.
Source: 1 NEWS
It said MetService had warned on Tuesday night that Auckland could be hit by 120km/h winds, while WeatherWatch itself had earlier warned at 2pm that gales were likely to cause power cuts and topple trees.
"So yes, forecasters did know strong gales, potentially damaging, were coming," the forecaster said this morning.
"However, no, the actual forecasts did not talk of such strong and damaging winds getting to hurricane force and up around the 200km/h mark."
WeatherWatch head forecaster Philip Duncan said the winds had become extra strong because a low coming out of the Tasman Sea had been fuelled by the powerful Antarctic southerly sweeping the country and "roaring up behind it".
And while the powerful winds were limited to a small area, this happened to be centred on Auckland.
Waikato, to the south, and Northland, to the north, were not badly affected by contrast, "so it was really the wind tunnel effect through Auckland coupled with a deepening low making landfall that helped ramp up these gales even further", Mr Duncan said.
He said the low weather system had now weakened and the worst winds had passed, but that strong gusts would continue off-and-on in Auckland through Wednesday.