Parts of the country could reach 30C this long weekend as the threat of drought hangs over the upcoming El Nino summer.
MetService has forecasted a high of 28C for Canterbury on Saturday, and 28C for Hastings and 27C for Napier on Labour Day.
Kaikōura down to Dunedin would see highs of 25 to 27C.
"We have warm, dry northwesterly winds coming over the ranges of the North Island, and the Southern Alps. This allows for hot and sunny days - so slip slop slap and wrap," MetService meteorologist Dom Barry said.
The North Island would see showers in many western, and some inland areas through to Monday, as cloud cover increased, MetService said.
Southern parts of the country and the West Coast could expect cloud and rain throughout the rest of the week, with a dramatic change in weather for the South Island on Monday, Barry said.
"A cold front sweeps up the South Island on Labour Day, bringing heavy rain and strong winds to southern and western areas as the day progresses," he said.
Heavy rain warnings and strong wind watches were possible.
Barry advised anyone travelling around the South Island on Labour Day to stay up to date with the latest forecast.
This front was a bit of a spring doozy, he said.
Meteorologist Chris Brandolino told Nine to Noon the second half of the long weekend, particularly Labour Day would see a return to the "more quintessential El Nino weather patterns".
"Westerly winds, rain for the west of the South Island, lower South Island. They've had a nice hiatus, a bit of a break over the past few weeks. It dried out. Things are quite wet in September down in that area.
"But they're probably going to see some pretty heavy rainfall as heavy rain, probably what we call an atmospheric river, which is basically a river in the sky of moisture."
Drought indicator maps showed a large part of the country was drier than usual, including the large agricultural regions of Waikato, Bay of Plenty, Taranaki, Tai Rawhiti and into Hawke's Bay.
Water restrictions were already in place in Hastings and Napier, Te Awamutu, Cambridge and Wellington.
Brandolino said the maps showed a lack of rainfall.
"Rainfall month to date for pretty much the entire country, unless you're in Timaru and Ōamaru and places like that, has been profoundly drier than usual, less than usual," he said.
"Places like in Northland, large sections of the North Island, Bay of Plenty, even lower North Island, less than half of what is typical to date for the month of October, and that dryness or lack of rain has been a theme as well for a good chunk of the South Island.
"If you wind the clock bit farther back to the 1st of August, so taking a longer view, it's really a tale of two islands."
The North Island was most unusually dry with a lack of rainfall, so many areas in the North Island were below normal, Brandolino said.
He said "below normal" was 80 percent or less of what was typical.
"Many locations in the North Island meet that criteria. Not the case for the South Island," Brandolino said.
"September was an exceptionally wet month for the lower and western South Island. Places like Gore getting more than double the normal rainfall. In Invercargill, we know about the medium-scale adverse event classified by MPI a few weeks ago because of that unusually wet September.
"That really did set them up for a really wet three-month period. So much of the South Island, bar Nelson and parts of Marlborough, has been pretty wet for the time of year since the 1st of August, and it's that lack of rainfall that really informs dryness.
"But as we get into the warmer season, it's going to be not only the lack of rain, but where there's going to be wind and where there's going to be warmer temperatures. All of that will accentuate dryness.
"What I like to remind people is that after you wash your hands in the restroom, where do you put your hands? Under a dryer. What comes out? Heat and wind does a really good job at removing moisture from your hands. It also does a pretty good job at removing moisture from the soil."
