Waitangi Day could prove to bring some of the hottest weather of the summer for some regions as hot air arrives from across the ditch.
It comes after MetService said that the atmosphere this weekend would be like a "festival-goer".
"Wild on Friday and Saturday but worn out and sedate by Sunday."
A strong cold front that brought heavy rain to the South Island's West Coast on Friday, and caused windy conditions that closed lanes and reduced speeds on the Auckland Harbour Bridge on Saturday, cleared to the east on Sunday.
This made way for a large area of high pressure which begins to dominate our weather into next week, MetService explained.
Hot conditions are expected to return to the eastern South Island on Monday, with Blenheim and Ashburton expected to reach 32C and Christchurch 30C respectively.
MetService meteorologist Clare O'Connor said that Waitangi Day will be sunny and dry across the North Island due to this ridge of high pressure.
"Maximum temperatures will be in the mid-to-high 20s, with the possibility of 30C for Gisborne and Hastings."
At Waitangi, a maximum temperature of 26C is expected on Tuesday.
It is a different story for the South Island as a strong northwest flow produces heavy rainfall for the lower South Island on Tuesday.
O'Connor said that the rain could get as far north as Greymouth in the west and Dunedin in the east.
"It's fine and dry over the rest of the island, but strong northwesterly winds are expected about Canterbury."
High temperatures are forecast, with 31C expected in Christchurch and 32C expected in Blenheim.
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