Indian Ocean: Tropical Cyclone Emnati tracking southwestward Feb. 22; landfall forecast in east-central Madagascar late Feb. 22 /update 5

Event

Tropical Cyclone Emnati has weakened from an intense tropical cyclone and is tracking southwestward in the Indian Ocean Feb. 22. As of 09:00 EAT, the storm's center of circulation was approximately 309 km (192 miles) east-southeast of Antananarivo, Madagascar. Forecast models indicate that the system will weaken slightly as it continues to track southwestward toward Madagascar's eastern coast, making landfall over east-central Madagascar, between Mananjary and Manakara, late Feb. 22. The storm system is likely to weaken into a severe tropical storm as it tracks southwestward over southern Madagascar from Feb. 23. The system is expected to move into the Mozambique Channel early Feb. 24 as a moderate tropical storm. Emnati is then expected to track southward into the Indian Ocean from Feb. 24-25, becoming a subtropical low pressure system. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

Disruptions occurred across parts of Mauritius and Reunion as the storm system passed to the north of the islands Feb. 19-21. Mauritius' Sir Seewoosagur Ramgoolam International Airport (MRU) suspended operations late Feb. 19-late Feb. 20. Reunion's Roland Garros Airport (RUN) suspended all flights from 13:30 RET Feb. 20 until 15:00 Feb. 21. Schools and other educational institutions were closed across Mauritius and Reunion on Feb. 21 and will remain closed in parts of Reunion on Feb. 22. In Reunion, around 1,500 people were without power as of late Feb. 21 due to downed power lines, and around 800 are without water supply. Route du Littoral will remain closed Feb. 22.

Government Advisories
As of Feb. 22, the Mauritius Meteorological Services has lifted all cyclone warnings; however, a strong swell warning is in effect for Agalega Island, with swells of 3-4 meters (10-13 feet) expected in the seas around the island.

Meteo France La Reunion has also lifted all cyclone warnings. Orange strong winds warnings (the middle level on a three-tier scale) have been issued for the south and southeast of the territory, and orange heavy swell warnings are in effect for the northwest, north, and northeast coasts. Winds of up to 100 kph (62 mph) and swells of over 4 meters (13 feet) are possible in the respective warning areas.

The Madagascar General Directorate of Meteorology has warned a clear deterioration in weather conditions is expected Feb. 22. Heavy rainfall is expected along much of the east coast, and will likely trigger flooding in areas where the heaviest accumulations occur. Strom surge and tidal flooding are possible in the vicinity of where Emnati makes landfall, and rough seas are expected, especially along the eastern coast. The following cyclone warnings have been issued:

Red imminent danger alert (the highest level on a three-tier scale): Atsimo Atsinanana, Atsinanana, Fitovinany, Mangoro, and Vatovavy regions and districts.
Yellow threat alert: Ambohidratrimo, Amoron'i Mania, Analanjirofo, Andramasina, Androy, Ansoy, Antananarivo Atsimondrano, Antananarivo Avaradrano, Antananarivo Renivohitra, Arivonimamo, Atsimo Andrefana, Manjakandriana, Matsiatra Ambony, and Vakinankaratra regions and districts.
Green warning alert: Alaotra, Anjozorobe, Ankazobe, Bongolava, Menabe, Miarinarivo and Soavinandriana regions and districts.

A red heavy swell warning (the highest level on a three-tier scale) has been issued along Madagascar's east and southwest coasts, and a yellow warning has been issued for the rest of the coastline.

Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming days.

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 airports in affected areas and temporary closures of ports are also possible.

Stagnant pools of water during and after flooding may increase the incidence of insect- and waterborne diseases, such as dengue fever, cholera, and malaria. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a serious health threat.

Advice

Activate contingency plans in areas where officials forecast tropical storm or tropical cyclone 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.