Chilly weather is heralding winter's approach, with frost and snow likely for the south of New Zealand next week.

Meteorologists are stopping short of describing it as an Arctic blast, but say the cooler air coming from the South Pole will be widely felt, with temperatures plunging by 5 to 10 degrees Celsius.

Niwa meteorologist Ben Noll says there will be two blasts of cold weather - one early next week with another more aggressive one at the end of the week.

Noll says expect frost and some snow on the mountains.