Snow, hail, thunder, lightning as cold front hits

Rolling thunder, lightning and pelting rain have been hitting New Zealand, with a cold front even bringing snow flurries to Canterbury.

Forecaster Weatherwatch said the majority of the country would be in for a cold snap today, with three quarters of New Zealand colder than normal.

MetService has warned of snow flurries on the summit of Lewis Pass in Canterbury until 7pm, and brief flurries on the Desert Road in the North Island tonight between 10pm and 2am.

Today would be the coldest day of the week for the South Island, while the North Island would be coldest later today and early Wednesday.

The high in Gore, Southland today is just 7 deg C but was expected to hit 20 deg C on Saturday.

The warmer weather this week is coming out of both the sub-tropics and the Australian interior, with that warmth to continue to early next week.

If a sub-tropical low forms over northern New Zealand next week then more sub-tropical winds may affect parts of the country.

But in typical autumnal fashion, 95 per cent of the country would be warmer than normal by Friday.

Lightning has been seen near Piha, Muriwai Beach and just south of Helensville, with a few strikes close to the Kaipara Harbour, MetService meteorologist Andy Best. A couple of lightning strikes had also been reported near Waiheke Island.

One Herald reader in Titirangi said torrential rain and rolling thunder had hit in the past hour, along with hailstones.

A cold front that started over the south of the North Island early this morning had moved up over Taranaki before hitting Auckland, with a line of heavy showers currently running all the way from western Northland down toward Pukekohe, Best said.

In the past few hours, there had been 90 lightning strikes across the country.

The cold front was moving northeast, he said.

Rain has been brief but heavy. Out west Oratia Cemetery had reported 4mm of rain in the past hour, while a sensor at Waiatarua Reserve in Meadowbank had reported 9mm. Further south Auckland International Airport was reporting only light showers.

Meanwhile in Taranaki a suspected lightning strike took out power to more than 400 properties in Hawera this morning.

Suppliers Powerco said electricity went off just before 10.20am, with 422 properties affected. A site investigation was under way, with power not estimated to be fully restored until 3pm.

A witness told NZME that the power went off after a lightning strike.

Over about two hours leading up to 10.45am, 120 lightning strikes had been recorded, most of them over the sea, Best said.

Waikato, Waitomo, Taumaranui, Taranaki, Whanganui, and Manawatu through to Wellington are also at moderate risk of thunderstorms this afternoon, MetService says.

"These thunderstorms are likely to bring localised heavy rain with intensities of 10 to 15 mm per hour, hail and for areas from Auckland to Whanganui strong wind gusts."

Thunderstorms are possible into the early hours of tomorrow for many areas.