Madagascar: Disruptions due to flooding ongoing across parts of the country as of Jan. 23

Event

Disruptions due to flooding are ongoing across parts of Madagascar as of Jan. 23. Heavy rainfall associated with the passage of tropical storm system Cheneso, which made landfall over Sava Region Jan. 19 before tracking southwestward over northern and central Madagascar, has triggered flooding in many northern and central regions. As of Jan. 23, the remnants of the storm system lay located off the west coast of central Madagascar and are expected to continue to bring further heavy downpours in the coming days.

As of early Jan. 23, the National Office for Risk and Disaster Management (BNGRC) has reported three fatalities associated with the passing of Cheneso and six other people are missing. More than 13,000 people have been affected across Analamanga, Analanjirofa, Betsiboka, Boeny, Diana, Sava, Sofia, and Vatovavy regions. Nearly 4,000 homes have been damaged by flooding across the affected areas, as well as dozens of schools, roads, and other infrastructure. Authorities have pre-emptively evacuated a number of residents along the Betsiboka and Mahajamba rivers in Betsiboka Region due to the risk of flooding.

Madagascar's General Directorate of Meteorology has warned of further intermittent rainfall across most of the country in the coming days, with persistent heavy downpours likely in northwestern, southeastern, and west-central parts of the country. Daily rainfall totals of 7-10 cm (3-4 inches) are expected in the worst-affected areas. As of Jan. 23, yellow heavy rainfall warnings (the middle level on a three-tier scale) have been issued across Analamanga, Boeny, Fitovinany, Melaky, and Vatovavy regions, as well as Ambanja District in Diana Region, Analalava, Antsohihy, Bealanana, Boriziny-Vaovao, and Mampikony districts in Sofia Region, Belon'i Tsiribihina and Miandrivazo districts in Menabe Region, and Farafangana, Vangaindrano, and Vondrozo districts in Atsimo-Atsinanana Region. A red flood watch has been issued for the Betsiboka River basin in Betsiboka Region. Yellow strong wind warnings have been issued for parts of the western and southeastern coastlines. Officials could update and possibly extend the coverage of weather alerts over the coming days.

Hazardous Conditions
Further sustained heavy rainfall could trigger additional flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed 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.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

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.

Severe weather could also trigger flight delays and cancellations at airports across Madagascar. Authorities may temporarily suspend port operations or close beach fronts if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.

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.

Resources

Madagascar General Directorate of Meteorology
Madagascar National Office for Risk and Disaster Management Facebook (BNGRC)