Severe thunderstorms could hit Auckland, Northland, and Coromandel this afternoon

The upper North Island is bracing for heavy rain and thunderstorms which could be severe, along with a possible tornado this afternoon and evening.

MetService has issued a severe thunderstorm watch for Northland, Auckland, Great Barrier Island and Coromandel Peninsula.

The forecaster says scattered heavy showers and thunderstorms are expected to develop over Northland, Auckland and Coromandel Peninsula later this afternoon and evening. 

There's a moderate risk of the thunderstorms becoming severe, producing localised downpours of 25 to 40mm/h, strong wind gusts of 90 km/h and a chance of small tornado, the warning issued just before 3.30pm stated.

People in these areas should be on the lookout for threatening weather conditions and monitor for possible severe thunderstorm warnings, MetService says.

Rain radar shows light or moderate falls occurring over much of the North Island this afternoon.