A state of emergency has been declared for the Gore District with heavy rainfall causing significant surface flooding.

Torrential rain is causing widespread flooding in Southland.

The region is under an orange heavy rain warning until late this evening.

Southland Regional Council says flood warnings have been activated for the Aparima River at Dunrobin, Hamilton Burn at Waterloo Road and Waiau River at Sunnyside.

Flood watches have been also issued for four other waterways.

Speaking on the campaign trail in Napier, Prime Minister Chris Hipkins said he was aware of the flooding in Southland and that NEMA would be providing further updates.

"I'd just encourage people in that region to follow the guidance, keep an eye on the weather report and follow the guidance of the local national emergency responders," he said.

Gore District Council said flooding had closed five local roads and a warning was in place for State Highway 94, just past the Croydon Lodge.

Invercargill City Council said falling trees had shut walking tracks in the city's Queens Park.

The council says it's being overwhelmed by calls for sandbags and teams are working as fast as possible to deliver them to residents.

West Coast Emergency Management has just finished a meeting with all relevant agencies to discuss their response if the weather gets bad.

MetService has heavy rain, wind and snow warnings in place for the majority of the South Island.

Canterbury lakes and rivers south of Arthur's Pass should expect up to 350-millimetres of rain in the next day or so.

Reproduced with permission