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A slow-moving monsoon depression unleashed lethal amounts of rain in South Asia earlier this week prior to forming into a tropical cyclone over the northern Bay of Bengal Wednesday. The cyclonic storm named Komen reached tropical storm strength and moved inland Thursday. Since then, it has been downgraded to a depression over Bangladesh, however it still has the potential to further drench regions that are already reeling from flooding and mudslides. Gusty winds and rough seas are adding to the dangers, which in all have claimed at least 39 lives in two countries.
For about a week, heavy rainfall has been pounding southern parts of Bangladesh and parts of neighboring Myanmar thanks to a weak area of low pressure – designated a "depression" by meteorologists in that region – that formed over Bangladesh in association with the seasonal monsoon.
Extreme Rainfall
Extreme Rainfall
Before becoming a named tropical cyclone, Komen was an unnamed monsoon depression that lingered near the coast of Bangladesh for days. The map shows rainfall reported over the 168-hour period ending midnight Thursday evening, July 30, Bangladesh Time.
Even for a region where average July rainfall exceeds 600 millimeters (2 feet), the rains have been exceptional. The coastal city of Chittagong reported more than 800 millimeters (32 inches) of rain in just a three-day period July 24 through 26.
Much of southeastern Bangladesh has seen repeated heavy rainfall on a daily basis over the past week. The results have been deadly. Five people died in a landslide in Cox's Bazar Monday according to the Bangladesh-based Daily Star. Four others were pulled from the mud alive. Two other people drowned in flooding elsewhere in the town of 52,000 residents, the report said. Cox's Bazar has reported more than three feet of rain since July 24, exceeding its already high monthly average rainfall of 924.6 millimeters (36.40 inches) according to Bangladesh Meteorological Department climate data.
After the depression became Cyclone Komen, additional casualties were reported along the coast of Bangladesh Wednesday.
The Daily Star said a boat capsized in rough seas off Cox's Bazar Wednesday, killing two and leaving six missing. Falling trees were blamed for two deaths, and a boy died when a wall collapsed onto him. The cyclone was also blamed for the death of a newborn who succumbed to respiratory disease while being carried to a cyclone shelter by her parents.
While official rainfall totals are harder to come by in Myanmar, the effects have been as devastating or worse. At least 27 people are reported dead due to flooding in western and central parts of that country, according to a report from the BBC. Some 17,000 homes had been destroyed as of Monday from the days-long deluge, according to China's state-run Xinhua news agency.
According to The Irrawaddy, a news portal covering Myanmar, power is out in several impoverished townships in the western part of the country, and a local leader voiced concern the damage may be heavier than local resources can handle.
Current Enhanced Satellite
Current Enhanced Satellite
The coldest and therefore highest cloud tops are shaded in dark red; these indicate vigorous thunderstorm development. Yellow to blue shades indicate lower clouds.
The monsoonal depression that spawned Komen moved offshore from Bangladesh before strengthening over the Bay of Bengal, but it soon reversed course and moved back toward shore. The Bangladesh Meteorological Department said the center of Komen made landfall along the coast of southeastern Bangladesh between Hatiya and Sandwip late Thursday afternoon local time. (Bangladesh is 10 hours ahead of U.S. Eastern Daylight Time.)
The lingering circulation could continue to bring torrential rainfall to the already-stricken region, which consists of low flood-prone coastal plains in southeast Bangladesh and a series of landslide-prone ridges from the interior of that area into western Myanmar. Bangladesh-based weather radars showed spiral bands of rain affecting southeastern Bangladesh during the day Friday.
The potential for flooding rainfall will also include parts of northeastern India. The India Meteorological Department has issued heavy rainfall warnings.
Rainfall Forecast
Rainfall Forecast
Forecast rainfall through Sunday. One inch equals 25.4 millimeters.
With several rivers already out of their banks, the additional rain will merely aggravate ongoing flooding.
Stay with The Weather Channel and weather.com as we continue to follow this dangerous situation in South and Southeast Asia.