Bangladesh: Adverse weather forecast nationwide through at least June 22 /update 1

Event

Heavy rainfall is forecast across most of Bangladesh through at least June 22 amid the ongoing active monsoon season. The heavy downpours will likely exacerbate the situation in areas where flood disruptions are ongoing following previous heavy rainfall, including flood-hit areas in the northeast of the country.

The Bangladesh Meteorological Department has forecast showers and thunderstorms, accompanied by strong wind gusts and lightning, across much of Rangpur, Rajshahi, Dhaka, Mymensingh, Khulna, Barishal, Chattogram, and Sylhet divisions June 20-21, with moderately heavy to very heavy rainfall likely over parts of Rangpur, Mymensingh, Barishal, Chattogram, and Sylhet divisions. The department has issued an intense lightning and heavy rainfall warning over Rangpur, Mymensingh, Dhaka, Khulna, Barishal, Chattogram, and Sylhet divisions June 20-21. Rainfall totals of 4-9 cm (1.5-3.5 inches) are expected over these areas, with localized heavier downpours. The intense rainfall could trigger landslides over hilly areas of Chattogram and Sylhet divisions.

Widespread disruptions are ongoing across parts of northeastern Bangladesh after heavy rainfall in recent days compounded the situation in a region where flooding has been ongoing since late May. A total of around 4.3 million people across the districts of Sylhet, Sunamganj, Moulivazar, Habiganj, Netrakona, and Brahmanbaria have been impacted by flooding. The worst-affected areas have been Sylhet and Sunamganj districts of Sylhet Division. As of June 19, at least 17 fatalities have been reported in flood-related incidents and around 25,000 people in Sylhet District and 65,000 people in Sunamganj District are being temporarily accommodated in hundreds of shelters established across the two affected districts. Widespread power outages and mobile communication cuts are ongoing in the region and many major roads have been damaged or inundated, leaving tens of thousands of people stranded. Flooded runways have forced Osmani International Airport (ZYL) in Sylhet to close since June 17. Authorities reported June 20 that they were testing safety equipment and clearing runways with the hope of resuming operations June 22; however, further rainfall and associated flooding in the coming days could delay any planned reopening.

Flooding and landslides have been reported in other parts of the country in recent days. The overflowing Brahmaputra River was causing flooding in Kurigram and Gaibandha districts of Rangpur Division June 20. The flooding is impacting around 250,000 people in Kurigram District and an unspecified number in Gaibandha. Flooding has also been reported in Feni and Chattogram districts of Chattogram Division. A dam burst in Feni and floodwaters have submerged parts of the port city of Chittagong as of June 20. Landslides have caused at least five fatalities in Chattogram District and one in Cox's Bazaar District June 17-20. Four other fatalities have been reported in Cox's Bazaar and Noakhali districts due to lightning strikes June 19.

Hazardous Conditions
Further 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 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 in affected regions. Authorities may temporarily suspend port operations or close beach fronts along the Bay of Bengal coast 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.

Health
Flooding could heighten the threat of disease outbreaks. Backflow from drains mixed with floodwaters can become trapped in open areas when inundations recede. These stagnant pools often become a breeding ground for mosquitoes and bacteria, increasing the incidence of insect- and water-borne diseases. Exposure to contaminated water from inundated industrial sites, sewer systems, and septic tanks also poses a significant health threat.

Advice

Seek updated information on weather and related disruptions, including road conditions, before driving or routing shipments through affected areas. Do not attempt to drive through flooded areas. Reconfirm rail and air travel arrangements before departure. Charge battery-powered devices if prolonged electricity outages occur.

Resources

Bangladesh Meteorological Department