03 Feb 2022 | 12:55 PM UTC
New Zealand: Adverse weather forecast to continue in western parts of South and North islands through at least Feb. 7 /update 2
Further severe weather forecast across western parts of South and North islands, New Zealand, through at least Feb. 7. Disruptions ongoing.
Event
An active weather front is forecast to bring further heavy rainfall and strong winds across western parts of the South Island and lower North Island through at least Feb. 7. The heavy rainfall is likely to cause rapid water level rises in streams and rivers. Localized flooding and landslides are likely. The rain might result in hazardous driving conditions.
As of early Feb. 4, the New Zealand National Meteorological Service (MetService) has issued the following warnings and watches:
Heavy Rain Warning - Red (the highest level on a three-tier scale): Buller and Westland from Otira northwards, including the Grey River Catchment area.
Heavy Rain Warning - Orange: Tasman west of Motueka; Rai valley, Richmond and Bryant Ranges, and Nelson Lakes; Westland south of Otira; and the headwaters of the Canterbury lakes and rivers.
Heavy Rain Watch: The Tararua Range, Kapiti-Horowhenua, Wellington, and Marlborough Sounds; Canterbury Foothills; and Taranaki, Taumarunui, and Taihape.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Authorities in Buller District declared a state of emergency Feb. 2 amid the ongoing heavy rainfall. Over 600 homes and businesses were temporarily without power in the district. Residents in the town of Westport are being urged to evacuate due to potential landslides and power cuts, with an evacuation center established at Greymouth Baptist Church. A care home in the town has been evacuated and Buller mayor Jaimie CLeine has said mandatory evacuation for residents could be ordered early Feb. 4. The small community of Seddonville, north of Westport, was cut off by a landslide late Feb. 3. Surface flooding following heavy rainfall closed State Highway 6 from Hira to the Rai Valley in the Nelson Tasman region Feb. 3. The same highway was also closed in south Westland. Flooding and landslides also closed Naitai Valley Road on the outskirts of Nelson. Rocks Road in Tasman District was also closed for a period Feb. 3 during high tide.
Hazardous Conditions
Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed or a lack of stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rainfall has saturated the soil. Power outages could occur throughout the affected area.
Transport
Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. The disruptive weather may cause some delays and cancellations at regional airports. Authorities may temporarily suspend port operations along the Tasman Sea if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic. Flooding could block regional rail lines; freight cancellations are possible in areas that see heavy rainfall and potential track blockages.
Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after conditions have improved - it could take days before any floodwaters recede and/or officials clear debris. If there is severe damage to infrastructure, repair or reconstruction efforts may result in residual disruptions.
Advice
Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.
