New Zealand weather: Patches of rain, but cold front to peter out as summer heat returns

The taste of summer Kiwis enjoyed over the Labour Weekend will linger a little while longer than first thought for large parts of the North Island, with a cold front from the south petering out.

New Zealand baked over the long weekend, with Christchurch, Dunedin and Kaikōura soaring to 29C and Auckland, Hamilton and Whangārei all basking in sunny, warm conditions of their own.

But the heat was cut short for the South Island, with Christchurch falling from 28C to 12C overnight on Sunday and Dunedin suffering a "fever-like shift in temperature" on Saturday night, plunging from 25C to 8C.

This was brought on by a cold front that's been making its way up the country since early in the weekend - but it looks set to pump the brakes just as it creeps towards the upper North Island.

"The front currently bringing rain to the lower North Island and upper South Island weakens as it moves north and eventually stalls over the central North Island on Wednesday," MetService meteorologist April Clark says.

"A ridge of high pressure and more settled weather takes hold over the country from midweek. Auckland and Northland escape widespread rain, but it does mean that the sticky nights will remain for those areas."

That ridge is expected to build over New Zealand across the next couple of days, bringing sunny conditions and dry air to the South and lower North Islands over the next couple of days.

"A front currently bringing rain to central New Zealand weakens as it stalls over the Bay of Plenty/Waikato region tomorrow," MetService says.

"A ridge of high pressure starts to build over the country tomorrow [Wednesday] bringing more settled weather before another active front pushes onto the South Island Friday."

NIWA Weather says the southerly's lack of progress into the upper North Island means "warmth will (once again) dominate later in the week".

Weather Watch head forecaster Philip Duncan says Northland is expected to reach 23C, Auckland 21C, and Otago 20C on Wednesday, although western parts of the lower North Island and upper South Island will also get a decent amount of rain.