Tropical Cyclone Mahasen (01B) made landfall Thursday northwest of Chittagong, Bangladesh, with peak winds near 50 mph (85 km/h).
At least six people were killed in Bangladesh, Reuters said on its news website.
Thousands of huts were destroyed and the coast suffered some flooding at high tide, according to Reuters. However, the damage was not as serious as had been feared, the website indicated.
More than 800,000 Bangladeshis had been evacuated ahead of the storm, the Australian ABC News website said.
Official warnings were downgraded later Thursday as the weakening storm swept inland.
Chittagong has had over 3 inches of rain so far from the storm, and more is likely into Thursday.
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 Monday night after the lead boat crashed into rocks, according to the United Nations. More than 50 people aboard the boats are feared dead.
This Infrared satellite image from Thursday, from the Joint Typhoon Warning Center, shows the clouds associated with Mahasen in Bangladesh.
Tropical Cyclone Mahasen could bring life-threatening conditions to millions of people from northeastern India and into Bangladesh and even Myanmar. The greatest threats at this time appear to be flooding and mudslides; however, any storm surge can still be dangerous due to the low elevations of this 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, Anthony Sagliani and Jim Andrews contributed to this story.
Following a dip in temperature during the middle of the week, summerlike warmth will rebound across much of the Northeast by this weekend.
An outbreak of severe weather is targeting areas from Texas to Nebraska Wednesday evening.
Daily episodes of severe thunderstorms and flooding downpours will impact the Plains this week, possibly lingering into the weekend.
While a few showers will pass east of the Bay Area, seasonable weather and sunshine will hold in place through the weekend.
The central and southern Plains will continue to be pummeled by strong storms for the next several days, but the most potent severe weather threat is likely to be during the Mother's Day weekend.
Wind, seas and surf will build in advance of what is likely to become the first tropical system of 2015 along the southeastern Atlantic coast of the United States late this week.
Natchez, MS (1840)
Great Natchez tornado: most deadly and destructive in all pre-U.S. Weather Bureau history. City in ruins; 340 killed, mostly by drowning in the river.
White Mountain 2, CA (1964)
-15 degrees; U.S. record for May (lower 48 states).
A few tornadoes touched down in Kansas and Iowa, killing two people. Thunderstorms in eastern Kansas produced baseball-sized hail at Scranton and golf ball-sized hail at Silverdale.