Wet, windy and a white Christmas for some

It's a white Christmas for some Southland residents, with a dusting of snow on mountains in Te Anau this morning.

The weather's not looking that flash for the South Island for Christmas Day.

Heavy rain is forecast for the West Coast, while showers with thunder and possibly hail could hit parts of Otago and Southland, MetService says.

Dunedin residents had to make the most of the sun this morning with showers in the afternoon which may be thundery with hail.

In holiday hotspots Queenstown, Wānaka and Alexandra it'll be mostly cloudy with occasional rain, and highs of 15°C, 16°C and 19°C, respectively.

Oamaru and Invercargill were also expected to get showers and possibly thundery hail in the afternoon and highs of 21°C and 17°C.

Meanwhile, orange heavy rain warnings are in place for the ranges in Buller, Westland and Grey districts (from Arthur's Pass northwards) and the Canterbury Headwaters (also from Arthur's Pass northwards) from early this morning, with thunderstorms possible.

Heavy rain watches have been issued for the Tasman District, the ranges of the Westland District (from Mount Cook to Arthur's Pass), and the Canterbury Headwaters (also from Mount Cook to Arthur's Pass).

There is a moderate chance these watches will be upgraded to warnings.

- Allied Media and RNZ