Weather: Is winter coming to Hawke's Bay?

A weak El Nino is the reason for why Hawke's Bay has been treated to mild temperatures throughout autumn. Photo / Paul Taylor

Winter is coming...or is it?

Meteorologists remain uncertain as Hawke's Bay has experienced an extremely mild autumn, and winter is looking much the same, according to Niwa.

Climate forecaster Seth Carrier says although their current winter outlook statistics only go until the beginning of July, conditions are looking mild so far.

"The full winter outlook which covers June, July and August will be available next month, but in Hawke's Bay and the Eastern North Island, there's a weak El Nino in place and that tends to lead to more westerly winds than normal," Carrier said.

Since that was the case, he predicted that rainfall would be less than normal.

"We're either looking at rainfall that will either be near normal or below normal and we're expecting temperatures in Hawke's Bay to be above average and this is down to those westerly winds.

"A lot of that involves the interior ranges on the west side of Hawke's Bay, the air then goes down the eastern side of those ranges and that causes the air to heat up and that's what helps lessen the chance of rainfall."

Carrier said the soil moisture levels were slightly drier than normal and in order to get them back to regular standards, the region would need to get a good splash of rain.

"You need a good recharge of rain to get those levels back up to speed and it doesn't look like that's on the cards at the moment."

Hawke's Bay experienced a relatively mild winter last year and Carrier said it was possible that this winter would be similar as sea temperatures also played a big part in climate conditions.

"Sea surface temperatures around New Zealand are warmer than normal and that's something we had last winter as well.

"Two summers ago, sea surface temperatures were a lot warmer than normal, in fact we were calling it a 'marine heatwave' and that plays a pretty big part into what the air temperatures will be."

Hawke's Bay almost had a repeat performance of a marine heatwave this year, but pockets of cooler weather prevented temperatures from matching the heatwave standards.

"Sea surface temperatures are still generally warmer than what they normally would be at this time of year, I think over the course of the winter they levels are likely to vary at times but I think it's possible that they'll remain a little bit warmer than normal."

The warmer temperatures were down to the settled weather Hawke's Bay encountered during the summer months and with high pressure sitting over a body of water, the mixing of the different layers didn't occur.

"It takes several weeks of quiet weather for this to happen, then if you have a period of active weather where there's a bit more wind, it tends to mix up those layers of the ocean and temperatures can be held down a little bit."