"This warmer and windier northwest flow will move up the South Island over Thursday and Friday then up and over all of New Zealand across the weekend and for much of next week too."
The northwest winds could become strong to gale through central New Zealand over the weekend and some eastern ranges on Sunday.
Wet weather in the west and dry out east was likely over the coming week.
Rain could be heavy at times over the weekend right up the West Coast, and also Taranaki.
However, Saturday and Sunday were forecast to be warmer than average for many regions, especially in the east.
A colder change was forecast to develop on Sunday and Monday in the lower half of the South Island, with westerly and southwest winds dominating next week.