Photo: RNZ / MARIKA KHABAZI
Thunderstorms are moving up the country and are due to hit much of the North Island as temperatures start to drop.
"Temperatures are starting to drop" - MetService meteorologist Dom Barry
"We currently have an active front that is impacting the country," MetService meteorologist Dom Barry told Morning Report on Tuesday.
"It has affected the likes of Westland already this morning - there have been quite a number of active thunderstorms there already.
A heavy rain watch was in place for the Westland and Grey districts and Southland from the Oreti River westwards until 8am.
Barry said the front was moving toward the likes of Kāpiti, Taranaki and the northern parts of Waikato and Taumarunui.
"We're expecting that to affect the rest of the North Island throughout this afternoon and into this evening.
"We're also expecting the possibility of some thunderstorms for the Canterbury region this morning as well."
The thunderstorms weren't expected to reach the severe category, but Barry encouraged people to keep up to date on the MetService website and app in case that changed.
There would be rain for "a lot of places" - though the downpours would miss Hawke's Bay and Gisborne, Barry said.
Cooler weather was starting to arrive after Monday's scorching heat that saw Wellington airport breaking its January record with 29.6C, and Kawarau hitting 32C. Hastings will drop from 32C to just 12C on Tuesday night.
"Temperatures are starting to drop [for] the majority of the country."
Wanaka and Queenstown would get to 18C or 19C, with an overnight low of 4C.
The heat had set up a "perfect mixture" of conditions for thunderstorms in parts of the lower North Island on Monday, with warm moist air from the north and the atmosphere a little unstable, meaning the air could rise.
"That air could rise up really high and generate some really, really intense downpours in some areas."
But the relief will be short-lived - MetService forecasting more heat from Thursday.
"With this, temperatures are once again set to rise into the mid-to late twenties for most."
A tropical cyclone brewing off the coast of Australia could potentially bring wind and wet weather to New Zealand at the start of February, MetService forecast.
"The current forecast is for this system to move westwards towards Australia and Queensland on Thursday," it said in a statement.