Kiwis should keep an umbrella handy as rain, thunderstorms, hail and even a tornado could lash parts of the North Island.
MetService said humid and unstable conditions are expected to bring thunderstorms to many areas of the North Island, which could produce localised heavy rain and hail.
"In the Bay of Plenty, including Rotorua, Waikato and the Coromandel Peninsula, there is a moderate risk some of the thunderstorms could become severe," MetService said.
"These severe thunderstorms could bring large hail greater than 20mm in diameter, strong winds gusting greater than 110 km/h, and even the risk of a small tornado."
MetService warned large hail could cause significant damage to crops, orchards, vines, glasshouses and vehicles, as well as make driving conditions hazardous.
"Wind gusts greater than 110 km/h in strength can cause some structural damage, including trees and power lines, and may make driving hazardous. If any tornadoes occur, they will only affect very localised areas."
MetService warned Kiwis to not "put your umbrella away yet" with another showery day on the cards.
"The low finally moves over us today, but instead of a high the next pattern will be westerlies and a series of fronts for the next few days," MetService said.
A severe thunderstorm watch has been issued by MetService until 7pm on Sunday for Coromandel Peninsula, Waikato, Bay of Plenty, Rotorua and Taupo.
The latest wild weather comes after a severe thunderstorm lashed the Auckland region, bringing traffic to a halt on the Southern Motorway.
A severe thunderstorm warning was issued for Auckland after MetService's weather radar detected them near north and central Auckland at 6:30pm on Saturday.
