Large areas of the North Island and parts of the South are bracing for severe thunderstorms, after the MetService issued fresh warnings today.

The severe thunderstorms are predicted from Northland through Auckland, to Taranaki, including the Coromandel, Bay of Plenty, and Taupō.

In the South Island, there's a heavy rain watch for Buller, the headwaters of the Cantebury Lakes, North Otago and Dunedin, and an Orange Heavy Rain Warning for Westland near Mount Cook.

The latest warnings follow a wild end to Easter Weekend for some, with strong winds bringing tornadoes to either side of the Cook Strait.

One hit Upper Moutere, in Tasman yesterday afternoon, followed by another in Kāpiti in the early hours of this morning.

A teenager is in hospital, after suffering severe cuts and a collapsed lung when his sleepout was destroyed.

Samantha Gee reports.