Auckland thunderstorms forecast with 90km/h winds and heavy rain

Eastern parts of the North Island and much of the South Island are at a low risk of thunderstorms in the morning but are predicted to be hit by showers.

Much of the North Island is at moderate risk of thunderstorms on Saturday morning. Photo / MetService

The risk of thunderstorms increases to moderate for more northern parts of the South Island, with hail potentially reaching 15mm in diameter.

There is a threat of thunderstorms for Auckland and most of the North Island on Saturday. Photo / NZME

The heavy rain watch should lift this morning for the Bay of Plenty east of Ōpōtiki, but North Otago and Dunedin are under a heavy rain watch from 4am to 7pm.

Thunderstorms are forecast to affect much of the North Island throughout the day and into the evening on Saturday. Photo / MetService

MetService predicts the wet weather will linger into Sunday and the North Island can expect scattered rain or showers, some of which will possibly be heavy.

Heavy rain is forecast for the South Island at the start of Sunday, but MetService said this should clear later in the day.

Isolated showers are then predicted for the west of the South Island in what is otherwise forecast to be a mainly fine Sunday.