Thunderstorms are forecast for the lower North Island, with strong winds and large hail possible.
MetService says thunderstorms moving up from the country are expected to reach Kaikoura by midday and the southern North Island this afternoon, with Wairarapa, Wellington and Marlborough expected to get the worst of the storms.
The weather agency said there is a possibility of some of these thunderstorms being severe, with hail greater than 20mm in diameter and wind gusts of 110kmh or more.
"Large hail can cause significant damage to crops, orchards, vines, glasshouses and vehicles, as well as make driving conditions hazardous.
"Wind gusts of this strength can cause some structural damage, including trees and power lines, and may also make driving hazardous," MetService said.
The risk of thunderstorms will decrease this evening, with severe storms unlikely after 4pm in the south and 8pm in the north.
Meanwhile a severe weather watch has been lifted for North Otago and South Canterbury, however scattered heavy showers with thunderstorms are possible in these areas this afternoon and evening.