Cyclone Sidr hits Bangladesh, killing an estimated 5,000 people and destroying parts of the world's largest mangrove forest, the Sundarbans.

Extremely Severe Cyclonic Storm Sidr (JTWC designation: 06B) was a tropical cyclone that resulted in one of the worst natural disasters in Bangladesh. The fourth named storm of the 2007 North Indian Ocean cyclone season, Sidr formed in the central Bay of Bengal, and quickly strengthened to reach peak 1-minute sustained winds of 260 km/h (160 mph), making it a Category-5 equivalent tropical cyclone on the Saffir–Simpson scale. The storm eventually made landfall in Bangladesh on November 15, 2007, causing large-scale evacuations. At least 3,447 deaths have been blamed on the storm, with some estimates reaching 15,000.Save the Children estimated the number of deaths associated with the cyclone to be between 3,100 and 10,000, while the Red Crescent Society reported on November 18 that the number of deaths could be up to 15,000. Other aid agencies have estimated a death toll of up to 15,000. International groups pledged US$95 million to repair the damage, which was estimated at 196.25 billion taka (US$2.31 billion).