Weather: Winter set to be warmer, wetter than usual

(Getty)
(Getty)

Winter has arrived, but don't expect the White Walkers to bear down on your town anytime soon.

NIWA says it's going to be a warmer-than-usual winter for most, and wetter -- particularly for those on the west coasts of both islands.

Principal scientist Chris Brandolino told Paul Henry this morning it's the result of warmer ocean temperatures to the west of the country.

An animation showing ocean temperatures released by NIWA on Wednesday shows large swathes of red in the Tasman Sea, meaning much of it will be 2degC to 3degC hotter than usual.

"Warm water provides more moisture, more energy for the atmosphere... that's fuel. That's a good reason why the past couple of weeks we've had these downpours, these thunderstorms."

Between June and August, there's a 50 percent chance rainfall will be above normal countrywide, 30 percent it'll be average, and 20 percent it'll be dry.

On the South Island's West Coast the chance of above-average rainfall is 70 percent.

The entire country is about 80 percent likely to have higher temperatures than normal. Canterbury is an exception, with the probability of warmer weather marginally lower at 65 percent.

But towards the end of winter this could all change, with the end of the El Nino phase -- unusually warm water in the Pacific.

"El Nino is done, for the record. We're going into what we call neutral," says Mr Brandolino. "There's a chance -- it's not a slam dunk -- that we'll head into La Nina as we head into spring."

That's the opposite -- when the Pacific cools down.

Either way, while the next few months will probably be fairly mild, don't leave your scarf and woollen jumpers in storage.

"It's important to remember even though we're expecting a warmer-than-usual winter... it doesn't mean there won't be cold snaps," says Mr Brandolino.

Newshub.