Mozambique Channel: Severe Tropical Storm Cheneso tracking south-southwestward in Mozambique Channel Jan. 26 /update 6

Event

Severe Tropical Storm Cheneso is tracking south-southwestward in the Mozambique Channel off the western coast of Madagascar Jan. 26. As of 15:00 EAT, the storm's center of circulation was approximately 356 km (221 miles) northeast of Europa Island.

Forecast models indicate that the system will strengthen into a tropical cyclone as it tracks generally southwestward Jan. 26-27. The system is forecast to stay more than 130 km (81 miles) off the western and southwestern coasts of Madagascar as it then tracks south-southwestward and subsequently south-southeastward late Jan. 27-28. Cheneso is then likely to weaken into a severe tropical storm and then a moderate tropical storm as it tracks southeastward into the southern Indian Ocean away from Madagascar late Jan. 28-30. Although it is not forecast to make another landfall, Cheneso is likely to impact the western and southwestern coasts of Madagascar as it passes over the coming days. Some uncertainty remains in the track and intensity forecast, and changes could occur in the coming days.

As of Jan. 26, the Madagascar General Directorate of Meteorology has issued yellow cyclone alerts (the middle level on a three-tier scale) for Belon'i Tsiribihina, Manja, and Morondava districts in Menabe Region and Morombe and Toliara I-II districts in Atsimo-Andrefana Region. Wind gusts of 50-70 kph (31-43 mph) are forecast along the coasts of Atsimo-Andrefana and Menabe regions Jan. 26. Additionally, heavy rainfall of 4-8 cm (1.6-3.2 inches) is forecast across Atsimo-Atsinanana, Boeny, Melaky, and Menabe regions as well as Analalava and Antsohihy districts in Sofia Region into Jan. 27. Authorities have issued yellow heavy rain warnings for these areas. Red strong wind warnings (the highest level on a three-tier scale) have been issued for much of the western, southwestern, and southeastern coastlines, as well as yellow warnings for parts of the northwestern coastline. Red strong swell warnings have been issued for parts of the western coastline and yellow warnings for parts of the northwestern, southwestern, and southeastern coastlines. Authorities will likely publish new advisories or update/rescind existing alerts throughout the system's progression in the coming days.

The system previously made landfall as a moderate tropical storm over Sava Region in northeastern Madagascar Jan. 19 and largely dissipated as it tracked southwestward over northern and west-central Madagascar Jan. 20-23 before reforming after emerging into the Mozambique Channel Jan. 24. Flooding-related disruptions have been reported across many parts of northern and central Madagascar following the passage of the storm system. As of Jan. 26, the National Office for Risk and Disaster Management (BNGRC) has reported eight fatalities associated with the passing of Cheneso; at least 20 other people are missing. The storm has impacted nearly 47,000 people across the country and has displaced more than 20,000 people. Over 12,000 homes have been damaged and more than 500 homes have been destroyed by flooding across the affected areas. Cheneso has also damaged dozens of schools and other infrastructure and road networks have been heavily disrupted, including along sections of several national highways. Areas where the ground is already saturated will be particularly susceptible to flooding during further heavy downpours associated with the storm system.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. Further evacuations, flash flooding, and landslides are possible where weather conditions prove hazardous. The inclement weather could trigger localized business, transport, and utility disruptions and render some bridges or roadways impassable. Flight disruptions at airports in the region 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 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. 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
Madagascar General Directorate of Meteorology