14 Jul 2022 | 02:44 AM UTC
New Zealand: Heavy rainfall and strong winds forecast in parts of northern North Island through at least early July 15
Heavy rainfall, strong winds forecast in parts of North Island, New Zealand, through early July 15. Flash flooding, disruptions possible.
Event
Heavy rainfall and strong winds are forecast in northern North Island through at least early July 15. A low-pressure system is forecast to track southeastwards across the northern North Island the evening of July 14 through early July 15.
As of the afternoon of July 14, the New Zealand National Meteorological Service (MetService) has issued the following warnings:
Orange Heavy Rain Warning (middle level on a three-tier scale): Northland; 5-7 cm (2-3 inches) of rain is likely to accumulate.
Yellow Heavy Rain Watch: Auckland including Great Barrier Island, Bay of Plenty, Coromandel Peninsula, Gisborne. and Hawke's Bay north of Mohaka.
Yellow Strong Wind Watch: Auckland including Great Barrier Island, Coromandel Peninsula, and Northland.
Road Snowfall Warning: Desert Road (SH1); 3-5 cm (1-2 inches) of snow is likely near the summit early July 15, with lesser amounts to elevations of 900 meters (2,953 feet).
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days. The heavy rain is likely to lead to rapid water level rises in rivers and streams. Surface flooding, landslides, and hazardous driving conditions are possible.
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, including but not limited to Auckland International 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.