Tropical Cyclone Mahasen (01B), which is now centered to the northeast of Sri Lanka, or several hundred miles south of Calcutta, India, will bring impacts to areas from eastern India to Bangladesh and Myanmar over the next few days.
On Monday and Tuesday, heavy rainfall associated with Mahasen fell across parts of Sri Lanka. Rainfall totaled 5.76 inches in Ratnapura and 4.45 inches in Kurunegala during this time. The Sri Lankan Disaster Management Centre reported that at least seven people have died due to flooding from the cyclone.
Multiple boats carrying more than 100 evacuees from Myanmar capsized on Monday after the lead boat crashed into rocks, according to the United Nations. More than 50 people aboard the boats are feared dead.
A satellite image from Tuesday shows clouds associated with Tropical Cyclone Mahasen to the north of Sri Lanka.
Mahasen is expected to take a northeastward track over the next few days. This track should bring the storm into an area of warm sea surface temperatures and lower wind shear allowing it to become better organized.
The METEO-7 satellite image from Tuesday, from the University of Wisconsin, shows the clouds associated with Mahasen near India and Sri Lanka
With this track, Tropical Cyclone Mahasen could bring life-threatening conditions to millions of people from northeastern India and into Bangladesh and even Myanmar.
The storm is expected to approach Bangladesh Wednesday night into Thursday morning. During that time. it is expected to reach a peak intensity of 75 mph (120 km/h). Mahasen may weaken somewhat prior to making landfall on Thursday afternoon, but the primary threat from the storm will be heavy rainfall throughout the region.
An additional concern is that parts of Bangladesh and northeast India have received over 12 inches of rain during the past two weeks, which is a normal total for the entire month of May. In particular, the coastal Bangladesh city of Chittagong, a city of 2.5 million people, received more than 15 inches of rain between May 3 and May 11. As a result, additional heavy rainfall from a tropical cyclone would likely produce widespread flooding of both coastal and inland areas and possible mudslides.
Farther west, rainfall amounts will be considerably lighter as compared to Bangladesh and coastal Myanmar. Calcutta (Kolkata), India, a city of more than 5 million people, will be very close to the western side of the storm system. At this point in time, it appears that they will have just a few showers and thunderstorms while the worst of the storm passes to their east. However, if the storm tracks a little farther west, there is the potential for a steadier and heavier period of rain on Thursday which could total a few inches.
Cyclones that have hit these areas in the past have been some of the most deadly across the globe. In 2008, Tropical Cyclone Nargis devastated parts of Myanmar with some estimates of more than 100,000 people killed by the storm. A tropical cyclone that hit Bangladesh in 1991 reportedly killed more than 100,000 people as well.
Even though this storm is not expected to be as powerful as either of these, it shows how much damage can be done by a tropical cyclone in this part of the world.
Meteorologists Rob Miller, Eric Wanenchak, Mark Paquette and Anthony Sagliani contributed to this story.