22 Sep 2023 | 03:59 AM UTC
New Zealand: Heavy rainfall, snowfall, and strong winds forecast across most of the country through at least Sept. 24 /update 2
Heavy rainfall, snowfall, and strong winds forecast across most of New Zealand through Sept. 24. Disruptions ongoing.
Event
Heavy rainfall, snowfall, and strong winds are forecast across most of the country through at least Sept. 24. A slow-moving front over the South Island is forecast to track onto the North Island late Sept. 22 and continue moving slowly eastward across the Island through Sept. 24. The New Zealand National Meteorological Service (MetService) has issued the following weather warnings as of Sept. 22:
Orange (middle level on a three-tier scale) Heavy Rain Warning: Bryant and northern Richmond ranges, headwaters of the Canterbury lakes and rivers south of Arthur's Pass, Tasman west of Motueka, and Westland south of Otira. The heaviest rainfall of up to 12 cm (5 inches) is forecast over Tasman west of Motueka.
Orange Heavy Snow Warning: Inland Canterbury, Central Otago, Queenstown Lakes north of a line from Wanaka to Ranfurly, and Mackenzie Country. The heaviest snowfall of up to 40 cm (16 inches) is forecast about the Mackenzie Basin.
Yellow Heavy Rain Watch: Buller, Canterbury Plains including Christchurch and Banks Peninsula, Kapiti Coast, Northland, Otago excluding Clutha, Taihape, Taranaki, Tararua Range, Taumarunui, Taupo west and south of the Lake, Wairarapa about and south of Featherston, Waitomo, Whanganui, Wellington, and Westland about and north of Otira.
Yellow Heavy Snow Watch: Central Otago and Queenstown Lakes about and south of a line from Wanaka to Ranfurly.
Road Snowfall Warning: Haast Pass (SH6), Lindis Pass (SH8), Arthur's Pass (SH73), 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 have declared states of emergency in Queenstown, Southland, and Gore due to major flooding. More than 100 people in Queenstown evacuated to emergency shelters, while authorities evacuated around 20 homes in Brecon Street, Reavers Lane, Fryer Street, and Hamilton Road due to flooding and landslides. There is no access to the Queenstown Medical Centre. Officials have established an emergency shelter at St Peters Church. Severe weather has resulted in flooding and landslides across isolated parts of the Queenstown town center, including Upper Brecon and Fryer streets as well as Reavers Lane and Hamilton Road.
Rainfall in Southland and Gore has eased, but the Mataura River has not yet peaked. The overflowing of the Aparima River cut off areas in Thornbury and some parts the Gore District. Flooding affected around 20 homes in Gore Sept. 21. A community emergency hub is in place at the Croydon Lodge in Gore and the Mataura Community Centre for people who need assistance. Authorities have closed the center at Otautau. Reports indicate power outages in Carmichael Road, Fairfax, Gropers Bush, Lora Gorge, Riverton, Te Anau Downs, and Winton in South Island. Authorities have urged Tuatapere residents to conserve water as the water treatment plant at Tuatapere is not operational due to flooding; residents have only eight hours of drinking water. Most schools in Southland and schools around the Central Business District in Queenstown are closed Sept. 4.
Queenstown Airport (ZQN) is open but some flights disruptions are possible. Dense fog caused domestic flight delays and cancellations at Auckland Airport (AKL) Sept. 21. International and domestic flights to Wellington, Christchurch, Dunedin, and Queenstown remain unaffected. Strong winds prompted flight delays and cancellations at Dunedin International Airport (DUD) Sept. 20. Another flight from Wellington had to return after it was unable to land. Authorities have suspended some ferry services connecting downtown Auckland to Waiheke Island and Half Moon Bay Sept. 21.
Parts of several highways are closed due to damage, landslides, and the risk of avalanches, including SH1 between Kitchen and Makene roads through the Mangamuka Gorge and between the intersections Glendhu Road and Charlton Road, SH 6 between Haast and Makarora and between Branxholme-Makarewa Road and Breeze Road, SH25A between Kopu and Hikuai, SH 80 from Aoraki to Lake Pukaki (Mount Cook Highway), and SH 99 between Wallacetown and the intersection with SH 6.
Where precipitation falls as rain, flash and areal flooding is possible. This may occur in low-lying communities near watercourses and other large bodies of water, as well as in urban areas with easily overwhelmed stormwater drainage systems. Sites downstream of large reservoirs may be subject to flash flooding after relatively short periods of intense rainfall.
Precipitation could fall as snow in the higher elevations over the coming days. Wind gusts could cause blowing and drifting snow; decreased visibility is likely in mountainous areas. Rain-induced landslides are possible in areas of elevated terrain; there is also the possibility of avalanches in mountainous areas where the snowpack has become unstable due to heavy snowfall. Power outages are likely throughout the affected area.
Floodwaters and related debris are likely to render some bridges, rail networks, or roadways impassable, impacting overland travel in and around the affected area. Flooding in urban areas will likely cause significant traffic congestion. Heavy snow will make driving hazardous in some areas; authorities will likely implement temporary road closures or detours in such locations. Mountain passes and tunnels could be closed as a precautionary measure during periods of intense snowfall.
The disruptive weather will likely cause additional delays and cancellations at airports across the affected region. Authorities will probably suspend port operations temporarily if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic. Flooding/snow could block regional rail lines, causing freight and passenger train delays and cancellations.
Disruptions triggered by inclement weather and resultant hazards, such as flooding or avalanches, will likely persist well after conditions have improved - it could take days before any floodwaters recede and/or officials clear debris. Repair or reconstruction efforts may result in residual disruptions if there is severe damage to infrastructure.
Advice
Monitor local media for weather-related updates and advisories. Seek updated information on road conditions before driving or routing shipments through areas where severe weather is forecast; plan for possible delivery delays throughout the affected area. Allow extra time to reach destinations and carry an emergency kit and warm clothes if driving is necessary, especially on secondary or rural routes that could become impassable. Charge battery-powered devices in the case of prolonged electricity outages.
