Rain and strong wind is starting to pick up around Fiordland and Westland as locals are urged to review emergency plans.

A major weather system is set to bring days of heavy rain and strong winds to the country's south, including parts of Fiordland, Otago and Canterbury.

Westland is expected to be hit hardest. The area is bracing for up to 800mm of rain, with locals being warned the "significant" weather event could cause flooding and slips.

MetService has issued a raft of orange weather warnings, saying a red warning - reserved for only the most extreme weather events - could be issued for Westland.

RNZ is New Zealand's statutory civil defence lifeline radio broadcaster, providing vital information and updates as they come to hand.

Check out the frequencies here.

The National Emergency Management Agency (NEMA) advises that in times of crisis or civil defence emergency a battery powered radio or a car radio remain essential lifelines if power is out and other forms of communication are unavailable.

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