Tasman Sea: Tropical Cyclone Gabrielle tracking southeastward towards Norfolk Island as of early Feb. 11 /update 3

Event

Tropical Cyclone Gabrielle is tracking southeastward in the Tasman Sea towards Norfolk Island, early Feb. 11. As of 09:00 NFDT, the storm's center of circulation was approximately 1080 km (670 miles) northwest of Auckland, New Zealand.

Forecast models indicate the system will make a close approach to Norfolk Island, Australia, the evening of Feb. 11, passing north of the island before making a close approach to far northern New Zealand Feb. 13. Some uncertainty remains in the track and intensity forecast; changes could occur in the coming days.

As of early Feb. 11, the Australian Bureau of Meteorology has warned of gales over Norfolk Island from the afternoon of Feb. 11. The wind strength is forecast to increase to 155 kph (96 mph) by late afternoon Feb. 11. Abnormally high tides and very heavy surf are likely around Norfolk Island, which may lead to localized damage and coastal erosion. Periods of heavy rain are forecast over the island Feb. 11 before easing Feb. 12.

Meteo France New Caledonia has issued orange (middle level on a three-tier scale) strong wind warnings across the South and Loyalty Islands provinces and yellow strong wind warnings across the rest of the territory.

New Zealand National Meteorological Service (MetService) has warned that Gabrielle will impact the far northern parts Feb. 12 before spreading to other parts of northern and central New Zealand. Significant heavy rain and potentially damaging winds are forecast for most of northern and central New Zealand; dangerous river conditions and significant flooding are likely. Landslides and floodwaters could damage roads, making some roads impassable and possibly isolating communities. Power outages are also very likely. Large waves and coastal inundation are possible near the exposed eastern coasts of North Island. The following watches and warnings are in place:

• Red (highest level on a three-tier scale) Heavy Rain Warning: Coromandel Peninsula and Gisborne north of Tolaga Bay through early Feb. 14. 30-40 cm (12-16 inches) of rain is forecast.

• Orange Heavy Rain Warning: Auckland north of Whangaparaoa including Great Barrier Island, Gisborne from Tolaga Bay southwards, Hawke's Bay, and Northland.

• Orange Strong Wind Warning: Auckland north of Whangaparaoa including Great Barrier Island, Coromandel Peninsula, and Northland.

• Yellow Heavy Rain Watch: Auckland from Whangaparaoa southwards and Wairarapa, including the Tararua District.

• Yellow Strong Wind Watch: most of central and southern North Island and far northern South Island.

Authorities will likely update and possibly extend the coverage of weather alerts over the coming days as the storm progresses.

Emergency Management Norfolk Island (EMNI) has issued a red alert for the island ahead of the storm. Residents should stay inside until further notice. An emergency shelter is located at Rawson Hall.

Authorities in Auckland have established emergency shelters in advance of the storm. A list of the available shelters can be found here. Air New Zealand (NZ) has warned that flight cancelations are likely Feb. 12-14 due to Tropical Cyclone Gabrielle.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. If weather conditions prove hazardous, localized evacuations, flash flooding, and landslides are possible.

The inclement weather could trigger localized business, transport, and utility disruptions and render some bridges or roadways impassable. Flight disruptions at regional airports and temporary closures of ports are also possible. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a severe health threat.

Advice

Activate contingency plans in areas where officials forecast tropical storm conditions. Heed any evacuation orders that may be issued. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents and necessary medications in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks.

Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.

Resources

Joint Typhoon Warning Center
Australian Bureau of Meteorology
Meteo France New Caledonia
New Zealand National Meteorological Service