Kiwis are waking to bone-rattling temperatures on Monday morning as a front bringing severe thunderstorms, very heavy rain and strong winds are expected to lash New Zealand.
A front, preceded by a moist northwesterly flow, is moving over the south of the South Island from the southwest, with a low on the front to the west of the South Island.
The front and low move northeast over central and northern New Zealand, which will bring a period of rain to most places, MetService said.
This has seen MetService issue weather warnings and watches for many parts of the country for Monday and Tuesday.
MetService told Newshub many places in the South Island woke to chilly temperatures on Monday morning.
The coldest place in New Zealand was Manapouri Airport, near Te Anau, with the temperature dropping to a numbing -4 degrees at 7am.
Slightly further north, Pukaki at the airport and Tekapo both had very chilly temperatures of -2C at 8am.
Queenstown Airport, at 5am through 9am, and Timaru at 7am were only slightly warmer at -1C. The average minimum temperature for Queenstown in June is -0.4C and for Timaru it's -0.1C.
The big cities around New Zealand all saw a cold morning, but none dropped into the negatives.
Warkworth in Auckland got down to 7C, but MetService said it was mostly 9C or 10C around 7am, with the average minimum temperature for June being 8.7C.
Slightly south in Hamilton, it was actually a warm June night of 10C, with the average minimum temperature for June being 4.6C.
The Capital also had a warm night, recording a temperature of 10C, with the average minimum being 7.4C.
In the South Island, Christchurch got down to 5C at 9am, while Dunedin Airport was the coldest major city at 0C from 1am to 4am. MetService said it was 6C in the city over the same time period.
MetService Meteorologist Alwyn Bakker told Newshub the temperatures were "nothing really out of the ordinary", but parts of the South Island are starting to hit negative overnight temperatures.
"It's been pretty cloudy for those major centres in the North Island, which kept the temperatures up overnight, and Christchurch and Dunedin also got periods of cloud overnight, which stopped it from dropping too low," Bakker said.
MetService meteorologist Andrew James told Newshub Kiwis will need to get the blankets out as temperatures are meant to drop even further later in the week once the front passes.
"It's going to be cold for most places, but about normal for this time of year. Later in the week, as that ridge comes over and the cold air hangs around, we actually see temperatures drop a little more overnight," he said.
James warns the bottom of the South Island, for a place like Alexandra, can expect a bone-rattling temperature of -4C on Thursday and Friday night.
"So once we have high pressure, clear skies, light winds, that's when we get our coldest temperatures overnight rather than during the actual cold outbreak," James told Newshub.
"While the system is here, there is still cloud overnight, still wind overnight and that stops things from getting too cool."
Weather watches and warning
The chilly temperatures come as a front hits New Zealand, which has seen MetService issue 11 weather warnings and watches.
MetService issued a severe thunderstorm warning for Hauraki and Western Bay of Plenty on Monday morning, which could bring "very heavy rain".
The forecaster said its weather radar detected a line of severe thunderstorms lying from Mayor Island to Waihi.
"This line of severe thunderstorms is moving towards the south, and is expected to lie from Mayor Island to Waihi at 10:37am and from Mayor Island to Waihi at 11:07am," MetService said.
"Very heavy rain can cause surface and/or flash flooding about streams, gullies and urban areas, and make driving conditions extremely hazardous," MetService said.
There is also a severe thunderstorm watch in place for the Coromandel Peninsula and Bay of Plenty from 10:21am to 1pm on Monday.
MetService said a band of heavy rain and a few embedded thunderstorms is lying across the far south of the Coromandel Peninsula and the far west of Bay of Plenty on Monday morning.
"There is a risk of localised downpours of 25 to 40 mm/h with this rainband until early this afternoon."
"Rainfall of this intensity can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips."
Heavy rain is also on the way for the eastern parts of the North Island, with a watch in place for the Coromandel Peninsula, Gisborne and Hawke's Bay until Tuesday evening.
Strong wind will also lash the large parts of the country, with a watch in place for Eastern Bay of Plenty, Taupo, Tongariro National Park, Taumarunui, Waitomo, south Waikato, Taranaki, Wellington, Marlborough Sounds, Nelson, Buller and Marlborough west of Wairau Valley but excluding the Sounds.
