Slim chance of next king tide colliding with storm: Niwa

Waves smash the beach at Long Bay near Coromandel Town just before high tide on 5 January. Photo / NZ Herald

Scientists and council workers will be keeping a close eye on the weather in case another storm collides with the next king tide.

But the chances of a storm coinciding at the peak of the next king tide again on 3 February and causing disastrous flooding like that seen earlier this month is unlikely, according to a Niwa scientist.

The next king tide, the fifth highest of the year and about 5cm lower than the biggest which rocked parts of the North Island on January 4, is due on the Saturday of Waitangi weekend.

The king tide will be at its highest in Tauranga at 9.49am, 10.21am in Thames and 10.30am in Auckland.

Niwa group manager of coastal and estuarine processes Scott Stephens said there would only be 5cm of a difference between the king tide in January and the one in February, but added there was a slim chance of it coinciding with a bad storm.

"It's highly unlikely to reach those kind of levels because you would have to have the same coincidence of a large storm hitting right on the peak which is the thing that made that last event so damaging."

While it was too early to tell what the weather would bring in February, Niwa scientists usually drew an accurate picture between three and four days in advance.

Stephens said the damage caused to the coastline on January 5 was a result of the peak of the storm hitting at the same time as the biggest tide of 2018.

"It wouldn't have done any flooding at all if it arrived a week later, but because it arrived right on the peak of that high tide that's when we get the problems".

The difference between the king tide and a high tide the week later was about 80cm.

"If we get a storm - even a moderate storm - on those high tide dates we often experience flooding at the coast. And what we got this time around was a king tide and also a really large storm because it was still quite large, and because it arrived right on the king tide it produced some of the highest levels we've seen in many places."

A Thames Coromandel District Council spokesman said the council was keeping a close eye on the weather and would warn residents as soon as it was alerted by MetService, which was usually a few days beforehand.

"If it's a king tide but the weather is calm then everything should be fine. If it coincides with another storm like we had on January 5 then people should take precautions about where they are."