WeatherWatch head forecaster Philip Duncan tells all you need to know about Ex cyclone Fili as it hurtles towards the East Coast. Video / NZ Herald
Emergency teams are warning towns may be cut off by floods and slips in the coming day as ex-tropical cyclone Fili brings torrential rain down the North Island's East Coast.
The weather system's first showers are already falling along Northland's coast, but it is Gisborne and Hawke's Bay that are expected to be hit hardest overnight as some areas endure violent winds and downpours lasting longer than 24 hours.
Residents in these areas are advised to prepare for heavy rain and to stay off the roads, which may become dangerous due to flooding, landslides and downed powerlines.
Overall, the system is expected to bring rain to most of the East Coast, but pass largely offshore until it reaches Gisborne tonight, MetService maps show.
MetService has put a heavy rain watch in place for the city lasting through to 9am tomorrow, while severe gales up to 90km/h are also expected to blow.
Heavier rain was likely to hit Great Barrier Island by 7pm tonight, before the Fili weather system moves down towards Tauranga.
That region along with the Bay of Plenty coast and Rotorua are under a heavy rain warning lasting 21 hours from 9pm tonight all the way through until 6pm tomorrow.
During that time up to 110mm could fall on the region, potentially causing rivers to rise rapidly, surface flooding and slips that could making driving hazardous.
Gales up to 120km/h could also buffet the region.
However, Gisborne and Hawke's Bay are expected to bear the full brunt of Fili.
Wind map showing the forecast passage of Tropical Cyclone Fili as the clearly-defined centre lies to the east of the North Island at midday on Wednesday. Photo / Supplied
Gisborne can expect between 200 and 300mm of rain from 10pm tonight until 10pm tomorrow with up to 35 to 50mm/h of rain likely in some parts of the region on Wednesday afternoon.
You can see why our friends @MetService have issued a red warning for parts of the eastern North Island.
For some areas, our in-house modelling is indicating 36 hour totals that are 1-3 times the normal amount for the entire month of April.
Wairoa will get even more soaked, with 250 to 350mm of rain likely to fall from 1am on Wednesday until 4am on Thursday. It will be the hardest hit late on Wednesday afternoon and evening, with between 35 and 50mm/h of rain possible.
MetService has warned that the amount of rain could lead to dangerous river conditions and significant flooding.
Gisborne District Council warned that "very large waves and coastal inundation" could occur.
Wairoa District Council chief executive Kitea Tipuna told residents to make sure they were prepared.
"Our district is already recovering from a massive saturation and further rain could potentially cause more flooding, slips and road closures. Heavy rain may cause streams and rivers to rise rapidly, surface flooding and slips are also possible and driving conditions may be hazardous," said Tipuna.
"People need to be aware they may lose their power, and trees and landslides already impacted from the end of March weather event could now be further compromised."
"Cyclone Fili is approaching the North Island from the subtropics on Tuesday, tracking southeastwards close to, or across, eastern parts of the North Island during Tuesday and Wednesday."
MetService warned widespread impacts to the North Island with heavy rain, severe gales and very large waves are likely to affect northeast and eastern coasts.
There is a heavy rain watch in place for Auckland and orange rain warnings in place for Great Barrier Island, Coromandel, Bay of Plenty, Rotorua, Hawke's Bay (excluding Wairoa District) and Northland east of Kaikohe.
From an Auckland perspective, Great Barrier Island sees the worst of Cyclone Fili ^GG pic.twitter.com/LigFfL73fG
Meanwhile, Waka Kotahi NZ Transport Agency has advised motorists to avoid unnecessary travel between late today and Thursday morning - and have warned the weather could lead to state highways being closed.
NZTA Waikato/BOP regional maintenance and operations manager Rob Campbell said both the forecast of wind and heavy rain were of concern.
"Stay alert for unreported hazards, such as surface flooding, slips, fallen trees and branches, and downed powerlines.
"If you must travel, slow down and maintain a greater following distance between your vehicle and the one in front. Treat all powerlines as live."
You'll find up-to-date State Highway information at: https://t.co/fChGUp28MH as any impacts on our roads occur. Please check prior your journey and take extra care for flooding, slips or fallen trees if you must be on the road. ^TP https://t.co/kGGkyWPTM9
— Waka Kotahi NZTA Waikato/BoP (@WakaKotahiWaiBP) April 11, 2022
Those in Northland were warned that conditions on the road could change quickly and to be alert.
"If you must travel, please slow down and maintain a greater following distance. Remember vehicles need three times more stopping distance in wet conditions," said NZTA Northland regional maintenance and operations manager Mark Owen.
Civil Defence told people to stay inside during severe weather. "Don't walk around outside. Don't drive unless absolutely necessary."
MetService was also instructing people to tie down or bring inside anything that wind could break or lift. Trampolines should be turned upside down to minimise the surface area exposed to the wind.
Power companies around the North Island have teams ready to respond if the bad weather causes chaos.
Counties Energy has storm response teams on standby south of Auckland and Powerco field crews are also ready to go should severe wind gusts hit Coromandel and Western Bay of Plenty from early evening today, and Taranaki from tomorrow morning.
Customers are also being urged to secure outdoor objects that can blow into power lines. Powerco network operations manager Scott Horniblow said trampolines, outdoor furniture and other loose items such as sheets of iron should be securely fixed to the ground.
"Wind-blown trampolines and loose roofing iron have caused multiple power outages in previous storms and are a major threat to people's safety."
Counties Energy general manager of operations Dale Carline said the company was preparing for a large-scale event and urged residents to do the same. It had already cancelled planned outages for the next two days.
"Please start your storm preparations now to lessen the impact on the electricity network and on your loved ones."
In the event of large-scale power outages, Counties Energy crew will move around the region isolating power to any damaged or downed lines and electrical equipment before working on restoring the network.
