16 Aug 2022 | 01:55 AM UTC
New Caledonia: Adverse weather forecast territory-wide through at least Aug. 18
Heavy rainfall and thunderstorms forecast across New Caledonia through Aug. 18. Disruptions to transport, business, and utilities possible.
Event
Thunderstorms and heavy rainfall are forecast across New Caledonia through at least Aug. 18. A low-pressure system near the northeast tip of Grande-Terre is forecast to bring heavy rainfall and thunderstorms across most of the territory through at least Aug. 18, with the rainfall easing Aug. 18. Forecast models indicate the heaviest rainfall of 5-10 cm (2-4 inches) over the South-East the afternoon of Aug. 16, with lesser rainfall in other areas. The flooding of creeks in Grande Terre is likely due to precipitation occurring on the relief. Additional rainfall accumulations of 10-15 cm (4-6 inches) are likely Aug. 17 while gusts of up to 85 kph (53 mph) are possible through Aug. 18.
As of early Aug. 16, Meteo France New Caledonia has issued the following weather warnings across the territory:
Orange heavy rainfall and thunderstorm warnings (the middle tier on a three-tier scale): far North and the east coast.
Yellow heavy rainfall and thunderstorm warnings: west coast, Isle of Pines, Belep, and the Loyalty Islands.
Yellow strong wind warnings: east coast, the far north, the Loyalty Islands and the Isle of Pines.
Authorities may issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Hazardous Conditions
The storms could produce rounds of heavy precipitation, strong winds, and isolated thunderstorm activity. 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
The severe weather could contribute to transport disruptions throughout the region. Additional traffic and commercial trucking delays might occur along regional highways. Flooding downpours could inundate other low-lying roads in areas with poor drainage. Strong winds might also pose a hazard to high-profile vehicles. Floodwaters and related debris may render further bridges or roadways impassable, impacting overland travel in and around the affected area. Flooding in urban areas could also result in significant traffic congestion.
The disruptive weather could cause delays and cancellations at airports in the region, including but not limited to La Tontouta International Airport (NOU). Authorities may temporarily suspend port operations if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic.
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 debris is cleared. If there is severe damage to infrastructure, repair or reconstruction efforts may result in residual disruptions.
Advice
Monitor local media for weather-related updates and advisories. Confirm all transport reservations and business arrangements prior to travel in the affected area. Seek updated information on road conditions before driving or routing shipments through areas where severe weather is forecast; plan for possible supply chain disruptions throughout the affected areas. Stay away from elevated streams, creeks, and other watercourses that are prone to flash flooding. Do not attempt to navigate flooded roadways. Exercise caution in elevated terrain due to the threat of landslides. Charge battery-powered devices in the case of prolonged electricity outages.
