Weather: Heavy rain forecast widens with more areas expected to get long weekend downpours

Significant heavy rain will fall in parts of the South Island from Sunday, and the North Island from Monday, the MetService is forecasting.

Heavy rain watches have been issued for Northland and Taranaki Maunga, as well as the headwaters of the Otago lakes and rivers.

These new weather alerts added to heavy rain warnings already in place for Westland, Grey District, Buller and parts of Nelson, starting from as early as midnight, and lasting through to Tuesday, in some places.

“We’re expecting about 350-450mm from the ranges of Westland and slightly lesser amounts about the Coast,” MetService meteorologist Ashlee Parkes said.

“And then about 300-400mm through the likes of some of the Nelson ranges.”