25 Jul 2022 | 04:30 AM UTC
New Zealand: Adverse weather forecast for most of South Island and northern and western North Island through at least July 27
Severe weather forecast across most of South Island and northern North Island, New Zealand, through July 27. Disruptions ongoing.
Event
A front is forecast to track slowly southwards over northern and central New Zealand through July 26, bringing heavy rainfall and east to northeast gales. An associated low located west of northern North Island is likely to also track slowly southwards through July 26 before weakening and crossing the South Island July 27.
As of early July 25, the New Zealand National Meteorological Service (MetService) has issued the following weather warnings:
Orange Heavy Rain Warning (the middle level on a three-tier scale): Auckland from Whangaparaoa northwards and the Great Barrier Island, Bay of Plenty from Kawerau westwards, Canterbury south of Rakaia River, Coromandel Peninsula, Dunedin, Mount Taranaki, Northland, north Otago, and Tasman about and west of Motueka.
Orange Strong Wind Warning: Auckland including Great Barrier Island and Northland.
Yellow Heavy Rain Watch: Auckland south of Whangaparaoa, Bay of Plenty east of Kawerau, Canterbury from Rakaia River northwards, Gisborne from Ruatoria northwards, and Marlborough.
Yellow Strong Wind Watch: Bay of Plenty, Buller, Coromandel Peninsula, and eastern Waikato.
Road Snowfall Warning: Lewis Pass (SH7), Lindis Pass (SH8), Porters Pass (SH73), and Crown Range Road.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Authorities in Auckland have canceled most ferry services July 25 and imposed speed limits on the Auckland Harbour Bridge due to hazardous conditions. Top Energy has reported more than 2500 homes and businesses without power across the Far North District in the Northland Region, including more than 1,750 customers in Paihia, Bay of Islands, due to damage to a key power line feeding the Haruru Substation in Northland. Peria and Pamapuria schools, east of Kaitaia Town, are closed due to flooding and power cuts. A truck crashed north of Matamata Town due to high winds early July 25, injuring one person and blocking the road.
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 the soil has become saturated by heavy rainfall. 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 delays and cancellations at regional airports, including but not limited to Auckland Airport (AKL). Authorities may temporarily suspend port operations 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.
