13 Jun 2022 | 04:38 AM UTC
New Zealand: Adverse weather forecast nationwide through at least June 15
Heavy rainfall, snow, and strong winds forecast most of New Zealand through at least June 15. Flash flooding, disruptions possible.
Event
Heavy rainfall, thunderstorms, snow, and strong winds are forecast over most of New Zealand through at least June 15. A series of storm fronts are forecast to bring heavy rain, severe gales, and severe thunderstorms across most of the country through June 15. As of June 13, the New Zealand National Meteorological Service (MetService) has issued the following warnings in advance of the storm:
Orange (middle level on a three-tier scale) Heavy Rain Warning: Horowhenua to Wellington north of Johnsonville and the Tararua Range; further rainfall of up to 8 cm (3 inches) of rainfall could occur in these areas.
Orange Strong Wind Warning: Buller, Hawke's Bay south of Hastings, Marlborough, Tararua District, Wairarapa about and south of Featherston, and Wellington.
Orange Heavy Swell Warning: Kapiti-Porirua Coast from Otaki to Cape Terawhiti.
Yellow Severe Thunderstorm Watch: Kapiti-Horowhenua, Manawatu, Taranaki, Tararua, Waikato, Wairarapa, Waitomo, Wanganui, and Wellington
Yellow Heavy Rain Watch: Buller and Westland from Otira northwards.
Yellow Strong Wind Watch: Bay of Plenty, Canterbury Plains from the Rangitata River northwards including Christchurch and Banks Peninsula, Clutha, Coromandel Peninsula, coastal Dunedin, southern Fiordland, Gisborne, Hawke's Bay, coastal North Otago, Northland to Waitomo, Rotorua, coastal Southland including Stewart Island, Taihape, Taranaki to Kapiti, and Wairarapa north of Featherston.
Road Snowfall Warning: Desert Road (SH1), Lewis Pass (SH7), Arthur's Pass (SH73), Milford Road (SH94), and Crown Range Road.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Westport-Carters Beach Airport (WSZ) is closed until at least 14:00 June 13; authorities will reassess the situation and provide updates. Officials are urging impacted residents in northern Buller to self-evacuate due to the storm surge early June 13. Authorities have closed the Auckland Harbour Bridge three times since early June 13 due to strong winds resulting in hazardous travel conditions. State Highway 67 was closed temporarily early June 13 at Granity due to debris.
SH 43 between Stratford and Taumarunui, Waihenga Bridge on SH 53, SH 56 in Opiki between the intersections with Alve Road and Tane Road, SH 1 Marton near the intersection with Calico Line, and SH 6 from 8 Mile to Inangahua at Upper Buller Gorge are closed due to flooding and landslides. SH 8 between Tarras and Omarama at Lindis Pass and SH 94 from Te Anau to Milford are also closed due to heavy snowfall and the risk of avalanches. At least 12 schools across the country are closed due to the severe weather.
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 some delays and cancellations at airports in the region. 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.
