Thunderstorms are beating their way across the upper North Island on Monday afternoon - but the weather is expected to clear up by Waitangi Day.
Over 33 strikes have been recorded so far, MetService warns, and a severe thunderstorm watch has been issued until 9pm today.
However the MetService says Te rā o Waitangi will see a marked improvement with a southwesterly flow developing across the country.
"After the main front passes through on Monday, a ridge establishes itself over New Zealand," says MetService meteorologist James Millward.
"This will bring much more settled conditions for Waitangi Day right across the country with some isolated showers around, but plenty of sunshine on offer too."
While there may be scattered showers around the lower South Island, the North Island is expected to be mostly fine.
"Cooler feel to the temperatures over the South Island for a couple of days, thanks to a southwest flow," MetService says.
"Will also be some snow on the higher ranges."
Auckland looks set for a high temperature of 24degC, whilst Wellington can expect 22degC and Christchurch 18degC.