22 Jun 2023 | 04:24 AM UTC
New Zealand: Adverse weather forecast over parts of northern and eastern North Island and far northeastern South Island through at least June 25 /update 1
Severe weather forecast over northern and central New Zealand through at least June 25. Flooding and disruptions possible.
Event
Severe weather is forecast over parts of northern and eastern North Island and far northeastern South Island through at least June 25. A low-pressure system is forecast to track slowly across northern New Zealand through June 24, bringing periods of heavy rain and possible thunderstorms. The rain will affect areas that are already saturated from recent rainfall; flooding is possible in low-lying areas and areas near water bodies, while landslides are possible on unstable slopes.
As of June 22, the Meteorological Service of New Zealand (MetService) has issued the following watches and warnings across the affected area:
Red Heavy Rain Warning (the highest level on a three-tier scale): Tairawhiti (Gisborne)
Orange Heavy Rain Warning: Bay of Plenty west of Te Puke, Coromandel Peninsula, Hawke's Bay from State Highway 5 southwards, Kaweka Forest Park, eastern Marlborough south of Ward, and Ruahine Range
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Authorities in Gisborne have advised residents in Te Karaka to self-evacuate due to the rising water levels in the Waipaoa River. The evacuation shelter is located at Te Karaka Area School. Reports indicate several landslides in Gisborne City.
Due to landslides, heavy rain, and flooding, multiple state highways are closed. State Highway 1 is closed between Kitchen Road and Makene Road through the Mangamuka Gorge, State Highway 2 is closed from Matawai to Te Karaka, State Highway 25A is closed between Kopu and Hikuai, and State Highway 35 is closed between Okitu and Ruatoria.
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 are possible in areas impacted by the weather system.
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 additional delays and cancellations at airports across the affected region. Flooding could block regional rail lines; freight cancellations are possible in areas subject to heavy rainfall and track blockages.
Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after weather 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 or reported. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.
