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.
MetService has this morning updated its heavy rain watches for Fiordland, Clutha, Southland, Clutha, Tasman and Buller District, for about the next 18 to 24 hours.
For Grey District, Westland District, and north of Hokitika, there is a heavy rain watch for the next 54 hours.
MetService says rainfall could reach or exceed the warning criteria in these areas in the next few days.
Westland is expected to be hit hardest. The area is bracing for up to 800mm of rain, and locals are being warned the "significant" weather event could cause flooding and slips.
MetService says a red warning - reserved for only the most extreme weather events - could be issued for Westland.
There is also a strong wind watch for Fiordland over the next nine hours, and the Canterbury High Country for the next 26 hours till 2pm on Wednesday.
While there are no warnings in place for Christchurch or Dunedin, MetService is forecasting rain with some heavy falls for the cities on Thursday before it eased on Friday.
Niwa is warning that flooding "is a concern" for the hardest-hit areas, and the National Emergency Management Agency says 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.
Heavy Rain Warning - Orange
Impact: Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous.
Area: Westland District south of Hokitika
Period: 62hrs from 10am Tue, 9 Apr - midnight Thu, 11 Apr
Forecast: Periods of heavy rain. Expect 600 to 800mm to accumulate about the ranges, and 200 to 300mm about the coast. Peak rates of 25 to 35 mm/h about the ranges from mid Tuesday afternoon until Wednesday evening, then again from mid Thursday morning onwards. This is a significant heavy rain event with the potential for upgrade to a Red Warning.
Area: Headwaters of Canterbury Lakes and Rivers south of Arthur's Pass
Period: 51hrs from 2pm Tue, 9 Apr - 5pm Thu, 11 Apr
Forecast: Periods of heavy rain. Expect 400 to 600mm about the main divide, and 200 to 300mm within 15km further east, especially south of the Rakaia River. Peak rates of 15 to 25 mm/h.
Area: Headwaters of the Otago Lakes and Rivers
Period: 22hrs from 10am Tue, 9 Apr - 8am Wed, 10 Apr
Forecast: Expect 200 to 300mm about the main divide, and 100 to 200mm within 15km further east. Peak rates of 15 to 25 mm/h. Heavy rain is likely to return later on Wednesday, with widespread rain through parts of Otago. A further Warning or Watch may be issued closer to the time.
Area: Fiordland about and north of George Sound
Period: 18hrs from 9am Tue, 9 Apr - 3am Wed, 10 Apr
Forecast: On top of what has already fallen, expect another 80 to 110 mm of rain. Peak rainfall rates of 15 to 25 mm/h. Heavy rain is likely to return on Wednesday afternoon and a further Watch or Warning is likely to be issued closer to the time.
- RNZ/ODT Online
