Strong northerlies blow initially on the East Coast of the North Island, before the change moves through.
The West Coast of the South Island sees morning rain and any thunderstorms ease to showers also, while afternoon sunny spells are even possible.
The rain picks up again from evening and overnight though, with further heavy rain and thunderstorms.
The east coast of the South Island, apart from some morning high cloud and a spot of rain first thing, breaks to a mostly sunny afternoon, along with breezy west to northwest winds.
Overnight northwesterly winds strengthen for much of the South Island – especially the upper half – in the east, with gales likely.
A southwest change moves onto Southland and Otago overnight, bringing some rain for a time and snow down to 500m – then easing around dawn on Friday.
– Aaron Wilkinson & Drew Chappell, WeatherWatch.co.nz