The first hint of winter has arrived, and a series of storm fronts will sweep the country over the coming days.

Parts of Bay of Plenty, Westland and Fiordland are under a heavy rain warning, with up to 90 millimetres of rain expected to fall today.

And some frosty temperatures are expected to follow, as a cold southerly moves in with snow expected to settle on some of the alpine passes and the Desert Road from tomorrow.

MetService forecaster Lewis Ferris spoke to Charlotte Cook.