Tag Archives: Bangladesh

Tropical Depression Forms Over Bay of Bengal

A tropical depression formed over the Bay of Bengal on Wednesday.  At 10:00 a.m. EST on Wednesday the center of the tropical depression was located at latitude 16.2°N and longitude 83.3°E which put it about 105 miles (170 km) south of Visakhapatnam, India.  The depression was moving toward the north-northeast at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1003 mb.

A low level center of circulation developed on the southwestern edge of a cluster of showers and thunderstorms over the Bay of Bengal and the Indian Meteorological Department classified the system as a depression.  The circulation is not particularly well organized.  As noted above, the low level center is on the southwestern side of showers and thunderstorms.  Several bands of showers and storms formed northeast of the center.  There were not many thunderstorms near the center of circulation.  There were bands of showers and lower clouds in the western half of the circulation.  An upper level trough over India is producing southwesterly winds which are blowing over the top of the depression.  Those winds are causing moderate vertical wind shear, which is tilting the upper part of the depression to the northeast of the low level center of circulation.  The depression also appears to be pulling drier air from India around the western side of the circulation.  The combination of wind shear and drier air is probably responsible for the asymmetrical distribution of thunderstorms.

The depression will move through an environment that is marginally favorable for intensification.  It will move over water there the Sea Surface Temperature is near 28.5°C.  So, there is enough energy in the upper ocean to support intensification.  However, the upper level trough over India will continue to cause moderate vertical wind shear, which will inhibit the consolidation of the low level circulation.  The depression is also likely to continue to draw in drier air from over India into the western part of the circulation.  The depression could strengthen, but it could also weaken if the upper level winds get stronger.

The trough over India is steering the depression slowly toward the north-northeast and that general motion is expected to continue.  On its anticipated track the depression is expected to move toward the northern Bay of Bengal during the next several days.  The depression could make landfall over northeastern India or Bangladesh later this week.

The primary risk from the depression will be locally heavy rain, which could cause flash floods in parts of eastern India and Bangladesh.  The wind will push water toward the north coast of the Bay of Bengal and the depression could cause a storm surge of several feet (approximately one meter).

Tropical Cyclone Forms Over Northern Bay of Bengal

A tropical cyclone formed over the northern Bay of Bengal on Thursday.  At 11:00 a.m. EDT on Thursday the center of the tropical cyclone was located at latitude 20.0°N and longitude 86.5°E which put it about 25 miles (40 km) south-southwest of Paradip, India.  The cyclone was moving toward the north-northeast at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 999 mb.

A center of low pressure developed within a broader area of showers and thunderstorms over the northern Bay of Bengal on Thursday.  A wide band of showers and thunderstorms wrapped around the eastern side of the circulation.  The center of circulation was west of that primary rainband.  Additional bands of showers and thunderstorms formed in other parts of the circulation.  The circulation exhibited enough organization and characteristics to be classified as a tropical cyclone.  The Indian Meteorological Department was giving the the system a classification of depression.

The tropical cyclone is being steered north by a ridge of high pressure to its east.  On its anticipated track the tropical cyclone with make landfall on the coast of the northern Bay of Bengal within 12 hours.  Although the tropical cyclone is moving over water where the Sea Surface Temperature is near 31°C and there is not much vertical wind shear, it does not have much time to intensify before the center moves inland.  The tropical cyclone could strenthen a little more prior to landfall.  It will bring a storm surge of several feet (one to two meters) to the coast along the northern Bay of Bengal.  The tropical cyclone will also drop locally heavy rain and flooding could occur in some parts of India and Bangladesh.

Stronger Tropical Cyclone Mora Near Landfall in Bangladesh

A stronger Tropical Cyclone Mora neared landfall between Cox’s Bazar and Chittagong, Bangladesh.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Mora was located at latitude 21.8°N and longitude 91.9°E which put it about 90 miles (145 km) south of Chittagong, Bangladesh.  Mora was moving toward the north at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 974 mb.  Tropical Cyclone Mora was the equivalent of a hurricane/typhoon.

The inner core of Tropical Cyclone Mora organized quickly on Monday.  The primary rainband wrapped entirely around the center of circulation and an eye formed.  Additional bands of showers and thunderstorms were revolving around the core Tropical Cyclone Mora.  Thunderstorms near the core of Mora generated strong upper level divergence which pumped out mass and allowed the surface pressure to decrease.  The decrease of pressure caused the surface winds to increase to hurricane/typhoon intensity.  Winds to hurricane/typhoon strength extended out about 25 miles (40 km) from the center.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.  The strongest winds were occurring in the eyewall and over the Bay of Bengal.

Tropical Cyclone Mora is moving around the western end of a subtropical ridge.  The ridge is steering Mora toward the north and that general motion is expected to continue for another 12 to 18 hours.  On its anticipated track the center of Tropical Cyclone Mora will move near the coast of Bangladesh between Cox’s Bazar and Chittagong.  The center is likely to make landfall near Chittagong during the next few hours.

The recent intensification of Tropical Cyclone Mora has made it a more dangerous storm.  The increased wind speed will increase the potential for wind damage.  In addition, stronger winds will increase the height of the storm surge along the coast.  A storm surge of 6 to 9 feet (2 to 3 meters) will be possible along the coast between Cox’s Bazar and Chittagong.  The increase in organization of the core has also created the potential for heavier rain and greater fresh water flooding of rivers and streams.

Tropical Cyclone Mora will start to weaken after the center makes landfall.  However, it will continue to generate areas of heavy rain while it moves inland over Bangladesh and northeastern India.

 

Tropical Cyclone Mora Intensifies As It Nears Bangladesh

Tropical Cyclone Mora intensified on Sunday as it moved closer to Bangladesh.  At 11:00 p.m. EDT on Sunday the center of Tropical Cyclone Mora was located at latitude 17.4°N and longitude 90.9°E which put it about 370 miles (595 km/h) south of Chittagong, Bangladesh.  Mora was moving toward the north at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 988 mb.

The structure of Tropical Cyclone Mora exhibited more organization on Sunday.  A primary rainband wrapped about two thirds of the way around northern and western sides of the circulation.  A tighter center of circulation was evident at the core of Tropical Cyclone Mora.  There were few thunderstorms east of the center of circulation.  The thunderstorms in the primary rainband were generating more upper level divergence which was pumping out mass to the west and north of the tropical cyclone.  The divergence was causing the surface pressure to decrease and was contributing the increase in wind speed.

Tropical Cyclone Mora will move through an environment that will be favorable for additional strengthening during the next 24 hours.  Mora will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge east of Mora is generating easterly winds that are blowing toward the top of the circulation.  The easterly winds are generating moderate vertical wind shear and they are probably responsible for the location of the primary rainband north and west of the center of circulation.  The vertical shear will slow the rate of intensification, but it will not prevent Tropical Cyclone Mora from intensifying further.  Mora could intensify into the equivalent of a hurricane/typhoon before it makes landfall.

Mora was being steered toward the north by a subtropical ridge located to the east of the tropical cyclone.  A general northward motion is expected to continue for another 24 to 36 hours.  On its anticipated track Tropical Cyclone Mora will approach the coast of Bangladesh in 18 to 24 hours.

Tropical Cyclone Mora could make landfall near Chittagong, Bangladesh.  Mora will bring gusty winds to Bangladesh and northwestern Myanmar.  It will produce locally heavy rain and create a risk for fresh water flooding.  Counterclockwise rotation will push water toward the coast and there could be a storm surge near and to the east of where the center makes landfall.  The surge could increase the water level at the coast by 6 to 8 feet (2 to 3 meters).

Tropical Cyclone 02B Forms Over the Bay of Bengal

A surface circulation formed over the Bay of Bengal on Saturday and the system was designated Tropical Cyclone 02B.  At 8:00 p.m. EDT on Saturday the center of Tropical Cyclone 02B was located at latitude 14.2°N and longitude 88.9°E which put it about 640 miles (1030 km) south-southwest of Chittagong, Bangladesh.  The tropical cyclone was moving toward the north-northeast at 4 m.p.h. (6 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 998 mb.

A low level center of circulation consolidated over the Bay of Bengal on Saturday.  The distribution of thunderstorms was asymmetrical.  Most of the thunderstorms in the inner part of the circulation developed west of the center.  There were some thunderstorms in outer bands northeast of the center, but there were few thunderstorms closer to the core of the circulation in the eastern half of the tropical cyclone.  The thunderstorms west of the center were producing upper level divergence which was pumping away mass to the west of the tropical cyclone.

Tropical Cyclone 02B will be moving through an environment that will be favorable for intensification.  It will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge east of the tropical cyclone is generating southeasterly winds which are blowing toward the top of the circulation.  Those winds are creating moderate vertical wind shear and the shear may be the reason why the thunderstorms were developing west of the center.  The shear will be strong enough to slow intensification, but it will not prevent intensification.  Tropical Cyclone 02B will intensify during the next two days and it could become the equivalent of a hurricane/typhoon.

A subtropical ridge located east of Tropical Cyclone 02B is steering it slowly toward the north-northeast.  A general north-northeasterly motion is expected to continue during the next several days.  On its anticipated track the center of Tropical Cyclone 02B could approach the coast of Bangladesh and northwestern Burma in about 48 hours.  Tropical Cyclone 02B could be the equivalent of a hurricane/typhoon by that time.  It could bring gusty winds and locally heavy rain when it makes landfall.  Heavy rain could cause fresh water flooding of rivers.  In addition the winds on the eastern side of Tropical Cyclone 02B will push water in the Bay of Bengal toward the coast.  A serious storm surge could occur along the coast east and near where the center makes landfall.

Possible Tropical Cyclone Developing Over Bay of Bengal

Satellite imagery indicates that a possible tropical cyclone may be developing over the Bay of Bengal.  Thunderstorms have increased and the system has been designated as Invest 94B.  At 8:00 p.m. EDT on Thursday the center of Invest 94B was located at latitude 11.8°N and longitude 88.7°E which put it about 575 miles (930 km) east of Chennai, India.  The invest was not moving much.  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1002 mb.

A circulation began to consolidate in an area of thunderstorms over the Bay of Bengal on Thursday.  Many more thunderstorms formed in the western half of the circulation.  Although there was still not a well defined center of circulation, some curved bands began to form.  A broad cyclonic circulation began to rotate counterclockwise.

Invest 94B was organizing in area that was favorable for further intensification.  It was moving over water where the Sea Surface Temperature was near 30°C.  An upper level ridge centered to the east of the invest was generating easterly winds that were blowing toward the top of the circulation.  The winds were producing some vertical wind shear and the shear may have contributed to the asymmetrical distribution of thunderstorms.  The shear could slow the development, but it is probably not strong enough to prevent the formation of a tropical cyclone.

Invest 94B did not move much during Thursday.  The is some uncertainty about the future track of the system.  Some numerical models are forecasting that the subtropical ridge to the east of Invest 94B will steer it toward the northern Bay of Bengal.

 

Tropical Cyclone Forms Near Andaman Islands

A tropical cyclone formed near the Andaman Islands over the Bay of Bengal on Wednesday.  At 10:00 p.m. EST on Wednesday the center of Tropical Cyclone 05B was located at latitude 11.6°N and longitude 92.1°E which put it about 710 miles (1145 km) southeast of Visakhapatnam, India.  The tropical cyclone was moving toward the north-northeast at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 997 mb.

An area of thunderstorms moved from the western Pacific Ocean into the southeastern Bay of Bengal.  The area of thunderstorms turned slowly northward near the Nicobar and Andaman Islands.  A distinct center of circulation began to organize inside the area of thunderstorms.  The Indian Meteorological Department classified the low pressure area as a depression and the Joint Typhoon Warning Center designated the system as Tropical Cyclone 05B.

The circulation of Tropical Cyclone 05B is still organizing.  A primary band of thunderstorms wraps around the northern and western side of the center of circulation.  Additional bands of thunderstorms are forming in the eastern half of the circulation.  Microwave satellite imagery suggests that an eye could be developing in the middle levels of the circulation.  The thunderstorms near the center are generating upper level divergence that is pumping out mass toward the northeast of the tropical cyclone.

Tropical Cyclone will be moving through an environment that is favorable for intensification.  It will be moving over water where the Sea Surface Temperature is near 29°C.  An upper level ridge to the west of the cyclone is producing northerly winds which are blowing across the top it.  However, the vertical wind shear is not significantly inhibiting the organization of the tropical cyclone.  Tropical Cyclone 05B could reach hurricane intensity in a couple of days.

A subtropical ridge is currently steering Tropical Cyclone 05B toward the north.  The center is moving just to the west of the Andaman Islands.  The subtropical ridge is forecast to strengthen and build toward the west.  As the ridge strengthens and extends farther west, it will start to steer the tropical cyclone toward the west.  On its anticipated track Tropical Cyclone 05B could approach the east coast of India in three or four days.

Tropical Cyclone 05B will continue to bring gusty winds and heavy rain to parts of the Andaman Islands on Thursday.  The tropical cyclone could bring strong winds, locally heavy rain, a storm surge and mudslides to southern India in a few days.

Tropical Cyclone Kyant Forms Over Bay of Bengal

Tropical Cyclone Kyant formed over the Bay of Bengal on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Cyclone Kyant was located at latitude 16.6°N and longitude 90.4°E which put it about 480 miles (770 km) east of Vishakhapatnam, India.  Kyant was moving toward the west at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 994 mb.

A cluster of thunderstorms persisted over the eastern Bay of Bengal during the past few days, but strong upper level easterly winds prevented the development of the system.  The upper level winds began to diminish on Monday and a low level circulation center began to develop on the eastern edge of the area of thunderstorms.  When the upper level winds became weaker, then thunderstorms were able to develop closer to the center of circulation.  The system acquired the structural characteristics associated with a tropical cyclone and the India Meteorological Department named it Kyant.

The circulation of Tropical Cyclone Kyant is still organizing.  Some vertical wind shear continues because of easterly upper level winds being generated by a ridge northeast of the tropical cyclone.  The shear is causing more of the thunderstorms to form in the western half of the circulation.  However, additional thunderstorms have developed closer to the center in recent hours and some spiral rainbands have formed.  The thunderstorms near the center are generating upper level divergence which is starting to pump out mass in all directions.

Tropical Cyclone Kyant will be moving through a favorable environment during the next several days.  It will move over water where the Sea Surface Temperature is near 30°C.  The upper level winds should remain weaker, and the vertical wind shear will not be strong enough to prevent strengthening.  Tropical Cyclone Kyant is likely to intensify and it could undergo a period of rapid intensification.

The upper level ridge is steering Tropical Cyclone Kyant toward the west and that general motion is expected to continue.  On its anticipated track Tropical Cyclone Kyant could approach the east coast of India in about 48 hours.  It could bring strong winds and very heavy rain to portions of eastern India later this week.

Tropical Cyclone Roanu Nearing Bangladesh

Tropical Cyclone Roanu moved closer to the northern coast of the Bay of Bengal on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Roanu was located at latitude 20.3°N and longitude 87.8°W which put it about 200 miles (320 km) south of Kolkata, India and about 355 miles (575 km) west-southwest of Chittagong, Bangladesh.  Roanu was moving toward the northeast at 11 m.p.h. (18 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 983 mb.

On Friday Tropical Cyclone Roanu went through another cycle in which most of the thunderstorms dissipated near the center of circulation and then convection redeveloped rapidly.  Thunderstorm activity is increasing at the core of the circulation and those storms are driving well developed upper level outflow.  Several well formed bands of thunderstorms are rotating around the center of circulation.  Roanu is more organized and it is a little more intense than it was 24 hours ago.

Tropical Cyclone Roanu is in an environment that could support a little more intensification before it makes landfall on the north coast of the Bay of Bengal.  It is over water where the Sea Surface Temperature is near 30.5°C.  Roanu is under an upper level ridge which means the upper level winds are light and there is not much vertical winds shear.  However, Roanu is getting closer to the north coast of the Bay of Bengal and it only has another 12 hours or so to intensify.

A ridge east of Roanu is steering the tropical cyclone toward the northeast and that general motion is expected to continue for the next several days.  On its anticipated track Tropical Cyclone Roanu will be near the coast of Bangladesh in about 12 hours.  Roanu is expected to continue moving toward the northeast after it makes landfall.

Although Tropical Cyclone Roanu could cause some minor wind damage, its main threats will be locally heavy rain and a moderate storm surge.  Tropical Cyclone Roanu could produce locally heavy rainfall, especially if the thunderstorm activity continues to pulse diurnally.  The heavy rain could produce significant fresh water flooding over parts of northeastern India, Bangladesh and Myanmar (Burma).  In addition, the winds on the eastern side of Tropical Cyclone Roanu will be blowing toward the coast of Bangladesh and those winds will push water toward the coast.  The north coast of the Bay of Bengal is particularly susceptible to storms surges and Roanu could bring a moderate storm surge to the coast of Bangladesh.  The surge will be higher in the mouths of rivers and other locations where the shape of the coast funnels the water into specific locations.

Tropical Cyclone Roanu Threatens Northern Bay of Bengal

Tropical Cyclone Roanu intensified on Thursday and it poses an increasing threat to the northern Bay of Bengal.  At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Roanu was located at latitude 17.9°N and longitude 84.9°E which put it about 125 miles (200 km) east of Visakhapatman, India and about 580 miles (935 km) west-southwest of Chittagong, Bangladesh.  Roanu was moving toward the north-northeast at 14 m.p.h. (23 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 70 m.p.h. (115 km/h).  The minimum surface pressure was 986 mb.

Most of the thunderstorms in Tropical Cyclone Roanu weakened earlier today and at times it did not look much like a tropical cyclone on satellite imagery.  However, a burst of thunderstorm activity near the center of Roanu has occurred in recent hours and an eyelike feature has appeared on conventional satellite imagery.  The structure of the circulation improved as a result of the new burst of thunderstorms.  The primary rainband now coils more tightly about three quarters of the way around the apparent center of circulation.  The thunderstorms near the center of circulation are generating upper level divergence which is pumping out mass in all directions.  Several additional bands of thunderstorms have developed over the eastern half of the circulation and Tropical Cyclone Roanu is stronger than it was 24 hours ago.

Tropical Cyclone Roanu is in an environment favorable for intensification.  It is over water where the Sea Surface Temperature is near 31°C.  Roanu has moved closer to the center of an upper level ridge and the upper levels are not as strong as they were yesterday.  As a result the vertical wind shear is much less and the upper level ridge is actually helping to pump mass away from the center of Roanu.  The center of the tropical cyclone is near the east coast of India, but the core is expected to remain over water on Friday.  Roanu is likely to strengthen further and it could reach hurricane/typhoon intensity.

A ridge east of Roanu is steering the tropical cyclone toward the northeast and that general motion is expected to continue.  On its anticipated track Roanu could be south of Kolkata, India in about 18 hours.  Tropical Cyclone Roanu could be approaching Chittagong, Bangladesh in 24 to 36 hours.

Tropical Cyclone Roanu poses a significant threat to the northern Bay of Bengal.  That area is vulnerable to storm surges.  Since Roanu will approach from the southwest, the winds in its counterclockwise circulation will push water toward the north coast of the Bay of Bengal.  In addition, a strengthening Tropical Cyclone Roanu will be capable of producing locally heavy rain which could cause inland flooding.