Hawke's Bay weather: Fog clears, but 'a bit of rain' is coming over weekend

Who dimmed the lights? A foggy start to the day in Havelock North. Photo / Warren Buckland

Hawke's Bay residents can expect wet days and warm nights for the next few days, typical of a long period of southeasterlies, a meteorologist says.

Residents woke up to a foggy start to Friday morning, but the haze cleared to a bright, blue sunny day.

MetService meteorologist Tui McInnes said the blanket of fog, which wasn't enough to delay flights out of the region, was "relatively common" and called it "advection fog".

"Advection fog occurs when moist air passes over a cool surface by advection [wind] and is cooled," he said.

"It is common as a warm front passes over an area with significant snow-pack."

McInnes said the fog formed inland, along State Highway 2.

"It was fairly widespread in the southern part of the region.

"It formed overnight, north of Dannevirke and south of Hastings, a southwesterly breeze this morning [Friday] pushed it over Napier and Hastings.

"It was getting flushed out the plains. Eventually, the sun cleared it away.

"The ocean takes a lot longer to warm up, so it hung around a bit," McInnes said.

A low-pressure system was developing towards the northeast of New Zealand, for the rest of the week.

"This would bring a long period of southeasterlies to Gisborne, Hawke's Bay and Wairarapa," he said.

"This brings a lot of moisture, wet weather, which means a mix of showers and rain for the region.

"Everywhere in Hawke's Bay is likely to see some rain in the next couple of days."

Temperatures in Napier and Hastings would stick to the mid-teens for the remainder of the week, and the coldest day would be next Tuesday, he said.

"Overnight temperatures will be quite warm, except for tonight when temperatures will drop to 6C in Hastings and 7C in Napier."

On Wednesday, the first visible "blood supermoon" in nearly 40 years will be seen in New Zealand, but Hawke's Bay might not be the best place to see it.

Blood moons - also known as total lunar eclipses - occur when the Earth lines up between the Moon and the Sun.

This hides the Moon from sunlight and blocks most of the blue light, with the remaining light refracting onto the Moon's surface and causing a red glow.

The lunar eclipse is due to last five hours, beginning at 8.47pm next Wednesday, and ending about 1.49am on Thursday.

However, the period of "totality", where the Moon is completely hidden from the Sun by Earth, and when the reddening is most noticeable, will only last about 14 minutes, from 11.11pm - making it one of the shortest eclipse totality periods.

McInnes said a low-pressure system sitting to the northeast of Aotearoa would bring southeasterly winds across most of the country - causing quite cloudy conditions, particularly for the east coast of the North Island (Te Ika-a-Māui).

That meant areas such as Hawke's Bay, Wairarapa, Gisborne, Bay of Plenty, Coromandel, Auckland and Northland were less likely to have an unencumbered view of the rare lunar phenomenon because of the expected overcast conditions.