From early morning to late afternoon, high winds will pass through the South Island - with heavy rain to accompany it.
The Christchurch CBD will miss most of the bad weather, with winds only expected to reach 31km/h and a high of 27 degrees.
MetService meteorologist John Law said the strongest winds will hit the Canterbury High Country.
"That's where we are going to find the highest winds, so from about 4 o'clock in the morning or so - right the way through in towards that early evening."
MetService said driving could be hazardous, especially in small vehicles like motorbikes.