A low pressure system from Australia has brought New Zealand's biggest rainfall of year and flooding to parts of South Island's West Coast.
MetService has issued severe weather warnings for most of South Island from the system, which has already brought huge rains to Westland before an expected peak on Thursday.
Almost 150mm was received at received at Milford Sound and Haast in the 24 hours to 9am on Wednesday, with heavier rainfall in mountain ranges.
The Waiho River, which runs through Franz Josef, surged above alert levels, causing some flooding and precautionary evacuations.
Some nearby small communities are without power with up to 400mm of further rainfall expected in Westland on Thursday.
The key highway along the remote West Coast, SH8, was closed between Haast and Franz Josef on Tuesday due to landslips, with crews re-establishing one lane on Wednesday.
The system is so widespread, heavy rain warnings have also been issued for the Taranaki and Northland regions of North Island as well as wind warnings for Canterbury and Wellington.
