Snow is expected to build up across parts of the lower South Island from Sunday morning, with a moderate chance of MetService upgrading its warnings.

Snow is expected to build up across parts of the lower South Island from Sunday morning, with a moderate chance of MetService upgrading its warnings.

A heavy rain warning has been issued for coastal Otago - with a chance of it turning into a red warning - as several other parts of the South Island brace for heavy snow and rain.