Across its path, Komen dropped torrential rainfall, primarily in northwestern Myanmar where the precipitation totaled at 840 mm (33 in) in Paletwa.

The government requested assistance from the international community to cope with the disaster, considered the worst in the country since Cyclone Nargis in 2008.

The monsoon spawned a low-pressure area on July 25 over the extreme northern Bay of Bengal and along the southern coast of Bangladesh.

At 03:00 UTC on July 26, the India Meteorological Department (IMD) classified the system as a depression, while the circulation was nearly stationary near the southern coast of Bangladesh.

[2] Early on July 27, the American-based Joint Typhoon Warning Center (JTWC) began monitoring the depression after the convection organized further, amplified by good outflow.

[2] The JTWC issued a Tropical Cyclone Formation Alert late on July 28, due to the increasingly defined circulation.

[4] On July 28, the system began moving more to the south and southeast, although its movement was very slow, possibly affected by another monsoon depression over western India.

[2] During that day, the circulation was somewhat elongated and exposed from the convection, while the thunderstorms in the southern periphery organized into spiral rainbands.

[6] At 18:00 UTC on July 29, the IMD upgraded the system to Cyclonic Storm Komen, one of only four storms of such intensity in July since 1965; typically, low-pressure areas that form in the month are in the extreme northern periphery of the Bay of Bengal, allowing little time to develop over waters, and usually impeded by wind shear.

Between 14:00–15:00 UTC that day, Komen made landfall on Bangladesh just west of Chittagong,[2] and the JTWC discontinued advisories once the storm was ashore.

[11] West Bengal Chief Minister Mamata Banerjee canceled an overseas trip to London to coordinate relief activities related to the storm.

[13] For several days, Komen dropped heavy rainfall across the northern Bay of Bengal and onto the adjacent coastlines of northwestern Myanmar, Bangladesh, and eastern India.

[14] Moving ashore Bangladesh, Komen was accompanied by a storm surge of 1 to 2 m (3.3 to 6.6 ft) that affected Chittagong,[2] while flooding rains caused landslides.gladesh, a station at Teknaf Upazila briefly recorded winds of 100 km/h (60 mph) on July 30.

[18] Komen killed 45 people in Bangladesh[19] – 21 in Cox's Bazar and 7 in Bandarban District[15] – some of whom due to illnesses spread by the storm.

[21] India, rainfall peaked at 520 mm (20 in) in Harinkhola, West Bengal, after the storm moved inland and tracked westward.

[36] Flooding from Komen was worst in Rakhine State,[39] where water distribution was contaminated,[40] and entire towns were largely destroyed.

[29] High winds in Lailenpi within Chin State damaged a school and a training center for community health workers.

[48] On July 31, President of Myanmar Thein Sein declared disaster areas for Chin and Rakhine states and for Sagaing and Magway regions.

[14] To help unemployed farm workers, the Bill & Melinda Gates Foundation financed a program to pay storm victims to rebuild damaged embankments and restore clean water access.

[58] An assessment by the United Nations, the World Bank, and the Myanmar government found that women and children were the worst affected group during and after the disaster, due to the stresses of the damaged houses, and insufficient food and assistance in the subsequent months.