Violent thunderstorms are to lash the country with torrential rain and flash flooding for the fifth day in a row.
MetService has issued a thunderstorm warning covering much of the country, and severe electrical storms are in store for the upper half of the North Island.
The electrical storms as set to hit after lunch, rumbling across the island from south of Auckland to Taihape. Those caught under the thunderous clouds can expect intense downpours packed with hail.
People are being warned there could be flash flooding and slips and to expect driving conditions to become dangerous during the downpours.
The South Island is also due to be rocked by the late spring storms. MetService has issued a moderate risk of thunderstorms from Nelson to Central Otago also after lunch.
Yesterday's thunderstorms brought heavy localised deluges with large hail stones sparking flash floods and slips.
On Tuesday more than 10,000 lightning strikes were recorded over the country and severe thunderstorm cells sparked warnings for the Mackenzie Basin and Marlborough.
WeatherWatchnz.co.nz head weather analyst Philip Duncan said the daily thunderstorm pattern was more typical for the peak of summer, not spring.
He explained that the thunderstorms occurred as easterly and westerly winds converged in the middle of the country. They typically start around lunch time, then peak from 3pm to 6pm in the North Island and 4pm to 7pm in the South Island because of their later sunset. The storms subside in the late evening.
"Then they'll pop back up again tomorrow morning like Groundhog Day.
"It's very unusual, this pattern. It's not normal in spring to have long spells of warmer than average calm weather. This is very much like the peak of summer.
"The word normal shouldn't be used. This isn't normal weather. I think it'll break quite a few records."
Duncan said some areas of the central plateau would see a month's worth of rain this week.
The thunderstorms will continue through until Saturday when a strong westerly takes over the country. The South Island will clear up on Saturday and the whole country will be clear on Sunday.
Fine weather would bring some relief next week except for a small sub-tropical low potentially brushing northern New Zealand, Duncan said.
But mid to late December looked more like spring when downpours and rain are expected from a front now traversing Australia.
