Western and southern parts of the South Island should brace for heavy rain this weekend while sunny and calm days are expected in the North Island.
MetService is predicting central parts of Westland could see between 250-350mm of rain in the next few days.
The rain is also expected to spill over into Canterbury.
A spokesperson said an active front is forecast to move slowly north across the South Island today and during the weekend, bringing heavy rain to some areas. The front may stall for a time about central or northern Westland.