21 Nov 2022 | 04:23 AM UTC
New Zealand: Adverse weather forecast over most of the country through at least Nov. 23
Severe weather forecast over most of New Zealand through Nov. 23. Possible flooding and associated disruptions.
Event
Heavy rainfall and strong winds are forecast across parts of northern and western North Island and central and western South Island through at least Nov. 23. A system is forecast to bring periods of heavy rain and possible thunderstorms to much of the country, especially to across the northern and western regions. North to northwesterly gales are also possible. The heaviest rainfall is likely in northern and central parts of the North Island as well as Westland and northern Fiordland. Heavy downpours could cause river levels to rise and trigger flooding as well as disruptions to transport due to ponding on road surfaces.
As of Nov. 21, the New Zealand National Meteorological Service (MetService) has issued the following weather warnings:
Orange (the middle level on a three-tier scale) Heavy Rain Warning: Bay of Plenty east of Opotiki, ranges of Gisborne, and north of Ruatoria.
Yellow Heavy Rain Watch: Northland, central North Island high country, North Taranaki including the mountain, ranges of Westland south of Otira, and Fiordland north of Doubtful Sound.
Yellow Strong Wind Watch: Auckland, Bay of Plenty, Canterbury High Country, Coromandel Peninsula, Gisborne, and Northland.
Heavy Swell Warning: Kapiti-Porirua Coast from Otaki to Cape Terawhiti.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
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 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. 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 with 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.
