Scattered thunderstorms are expected to affect parts of the central and northern North Island this afternoon and evening, says a MetService spokesperson.

"These thunderstorms will bring localised heavy rain and hail."

The regions expected to be affected by the scattered thunderstorms are Northland, Auckland, Waikato, Waitomo, Taumarunui, western Taupo, Rotorua and near the Kaimai Range.

"Some of the thunderstorms could be severe between 2pm and 9pm, with localised downpours of 25-45 mm per hour. There is also a low risk of a small and very localised tornado within this area."

Rainfall of this intensity can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips.

Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain.

A Severe Thunderstorm Watch means conditions are favourable for severe thunderstorms in and close to the watch area. People in these areas should be on the lookout for threatening weather conditions and monitor for possible Severe Thunderstorm Warnings.

For information on preparing for and keeping safe during a storm, see the Civil Defence Get Ready website