A red heavy rain warning has been issued for parts of Otago with up to 150 millimetres of rain expected to fall in some areas.
Residents in Otago and Dunedin have been warned to stay off the roads and go home.
Coromandel Peninsula was dealing with power cuts and blocked roads on Thursday morning.
Now MetService has upgraded its warning for North Otago, Dunedin and coastal Clutha, saying rain will disrupt travel, make some roads impassable, and isolate communities.
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