Civil Defence is bracing for the worst as wild weather is set to thrash the upper South Island.  

MetService has issued a red heavy rain warning for Tasman off the back of three weeks of rain saturated the region.  

Nelson-Tasman's under a state of emergency and has activated its emergency operations centre. 

Civil Defence Controller Alec Louverdis says they have clear messages to those at risk.  

He says previously flooded residents should self-evacuate and those in region should avoid roads or going near waterways as it's a threat to life.  

Orange rain warnings are also in effect for Marlborough, Mount Taranaki, east of Kawerau, Waikato, the Coromandel, Auckland, and Northland. 

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