Tag Archives: 04B

Tropical Cyclone Nivar Moves along Andhra Pradesh Coast

Tropical Cyclone Nivar moved northward along the coast of Andhra Pradesh on Thursday. At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Nivar was located at latitude 14.0°N and longitude 80.7°E which put it about 50 miles (80 km) south-southeast of Nellore, India. Nivar was moving toward the north at 7 m.p.h. (11 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.

After making landfall on the southeast coast of India near Puducherry on Wednesday, vertical wind shear blew the upper portion of Tropical Cyclone Nivar west of the surface circulation. An upper level ridge over India produced easterly winds which blew toward the top of Tropical Cyclone Nivar. Those winds caused strong vertical wind shear. The shear was strong enough to blow the upper part of Nivar west of the surface circulation. The upper part of the circulation moved westward across southern India and weakened. The surface circulation moved northward along the southeast coast of India and back over the Bay of Bengal north of Chennai.

Tropical Cyclone Nivar will move through an environment that will be only slightly favorable for intensification during the next few hours. Nivar will move over water where the Sea Surface Temperature is near 29°C, while it is over the Bay of Bengal. However, the upper level ridge will continue to cause strong vertical wind shear. The shear is likely to prevent Tropical Cyclone Nivar from strengthening.

Tropical Cyclone Nivar will continue to move north along the southeast coast of India for the next few hours. After that time a high pressure system over northern India will turn Nivar toward the west. On its anticipated track Tropical Cyclone Nivar is forecast to move inland over southern Andhra Pradesh and to move toward Karnataka. Nivar will weaken after the low level circulation moves inland, but it will drop locally heavy rain over southern Andhra Pradesh and Karnataka. Flash floods could occur in some locations.

Tropical Cyclone Nivar Makes Landfall in Tamil Nadu

Tropical Cyclone Nivar made landfall on the coast of Tamil Nadu on Wednesday. At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Nivar was located at latitude 12.2°N and longitude 79.8°E which put it about 25 miles (40 km) north of Puducherry, India. Nivar was moving toward the west-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 976 mb.

Tropical Cyclone Nivar made landfall on the southeast coast of India north of Puducherry on Wednesday. Nivar strengthened into the equivalent of a hurricane/typhoon over the Bay of Bengal before it made landfall. Winds to hurricane/typhoon force extended out 35 miles (55 km/h) from the center of Tropical Cyclone Nivar. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation.

Tropical Cyclone Nivar will produce gusty winds along the coast of Tamil Nadu between Cuddalore and Chennai. Winds blowing water toward the coast could cause a storm surge of up to six feet (two meters) between Puducherry and Chennai. Nivar will drop heavy rain over parts of northern Tamil Nadu and flash floods could occur in some locations.

Tropical Cyclone Nivar will move south of a high pressure system over India and the Bay of Bengal. The high will steer Nivar toward the west-northwest. The wind speed will steadily decrease when Tropical Cyclone Nivar moves inland. Nivar will drop locally heavy rain over parts of southern Andhra Pradesh and Karnataka when it moves farther inland over southern India.

Tropical Cyclone Nivar Strengthens near Southeast India

Tropical Cyclone Nivar (04B) strengthened over the Bay of Bengal near Southeast India on Tuesday. At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Nivar was located at latitude 10.8°N and longitude 82.6°E which put it about 235 miles (380 km) southeast of Chennai India. Nivar was moving toward the northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h). The minimum surface pressure was 982 mb.

Tropical Cyclone Nivar strengthened to almost the equivalent of a hurricane/typhoon over the Bay of Bengal near Tamil Nadu on Tuesday. More thunderstorms developed near the center of Nivar. Other strong thunderstorms were occurring in bands north and west of the center of circulation. Bands south and east of the center consisted primarily of showers and lower clouds. Storms near the center generated upper level divergence which pumped mass away to the north and west of the tropical cyclone. Winds to tropical storm force extended out 110 miles (175 km) from the center of circulation.

Tropical Cyclone Nivar will move through an environment favorable for intensification during the next 24 hours. Nivar will move over water where the Sea Surface Temperature is near 29°C. It will move under the western end of an upper level ridge over the Bay of Bengal. The ridge will enhance the upper level divergence and contribute to the removal of mass, which will cause the surface pressure to decrease. Tropical Cyclone Nivar will intensify into the equivalent of a hurricane/typhoon during the next 24 hours.

Tropical Cyclone Nivar will move around the western part of a high pressure system over Bay of Bengal. The high will steer Nivar toward the northwest during the next 24 hours. On its anticipated track Tropical Cyclone Nivar will make landfall on the coast of India between Puducherry and Chennai in about 24 hours. Nivar will bring strong winds to southern India. Wind blowing water toward the coast will cause a storm surge of up to 6 feet (2 meters). Tropical Cyclone Nivar will drop heavy rain over parts of Tamil Nadu and flash floods could occur.

Tropical Cyclone 04B Forms over Bay of Bengal

Tropical Cyclone 04B formed over the Bay of Bengal east of Sri Lanka. At 4:00 p.m. EST on Monday the center of Tropical Cyclone Gati (03A) was located at latitude 9.9°N and longitude 83.0°E which put it about 210 miles (340 km) east-southeast of Puducherry India and about 200 miles (320 km) east of Jaffna, Sri Lanka. It was moving toward the west at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 997 mb.

The circulation around a low pressure system east of Sri Lanka strengthened on Monday. More thunderstorms developed near the center of the low and the wind speeds increased. The distribution of thunderstorms around the low was asymmetrical. Most of the thunderstorms were occurring in bands in the western half of the circulation. Bands in the eastern half of the tropical cyclone consisted primarily of showers and lower clouds. Storms near the center of circulation generated upper level divergence which pumped mass away to the west of the tropical cyclone.

Tropical Cyclone 04B will move through an environment that is mostly favorable for intensification during the next during the next 36 hours. It will move over water where the Sea Surface Temperature is near 29°C. The tropical cyclone will move under the southern side of an upper level ridge over the Bay of Bengal. The ridge will produce easterly winds which will blow toward the top of the circulation. Those winds will cause moderate vertical wind shear and they are probably the reason for the asymmetrical distribution of thunderstorms. The wind shear will slow the rate of intensification, but the shear will not be large enough to keep the tropical cyclone from strengthening. Tropical Cyclone 04B could intensify into the equivalent of a hurricane/typhoon with 36 hours.

Tropical Cyclone 04B will move south of a ridge of high pressure over the Bay of Bengal. The high will steer the tropical cyclone toward the west-northwest. On its anticipated track the center of Tropical Cyclone 04B will pass north of Sri Lanka in about 24 hours. The tropical cyclone will approach the coast of India near Puducherry in 36 hours. It could be the equivalent of a hurricane/typhoon when it reaches the southeast coast of India.

Tropical Cyclone 04B will drop locally heavy rain over northern Sri Lanka. It will bring strong winds and locally heavy rain to southern India later this week. Heavy rain could cause flash floods in some locations.

Elsewhere, Tropical Cyclone Gati weakened as it moved across northeastern Somalia toward the Gulf of Aden. At 4:00 p.m. EST on Monday the center of Tropical Cyclone Gati (03A) was located at latitude 11.9°N and longitude 47.5°E which put it about 45 miles (75 km) northwest of Maydh, Somalia. Gati was moving toward the west-northwest at 13 m.p.h. (20 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.

Tropical Cyclone 04B Develops Over Northern Bay of Bengal

Tropical Cyclone 04B developed over the northern Bay of Bengal on Friday.  The circulation around an area of low pressure southeast of India strengthened on Friday and the Joint Typhoon Warning Center (JTWC) designated the system as Tropical Cyclone 04B.  Data from a scatterometer on a satellite indicated there were winds to 45 m.p.h. (75 km/h) in the western part of the circulation.  The Indian Meteorological Department was classifying the low pressure system as a depression and that was why it did not have a name.

At 4:00 p.m. EDT on Friday the center of Tropical Cyclone 04B was located at latitude 18.7°N and longitude 86.9°E which put it about 340 miles (550 km) southwest of Kolkata, India.  It was moving toward the north at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 994 mb.

Although there was a well defined low level center of circulation, the rest of the circulation of Tropical Cyclone 04B was not particularly well organized.  There were no strong thunderstorms near the center of circulation.  The stronger thunderstorms were occurring in a rainband 80 miles (130 km) northeast of the center of circulation.  Other bands revolving around the center consisted primarily of low clouds and showers.

Tropical Cyclone 04B is moving through an environment that is only marginally favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 28°C.  So, there is enough energy in the upper ocean to support intensification, but that is about the only factor favorable for intensification.  Tropical Cyclone 04B is moving underneath the western end of an upper level ridge.  The ridge is producing southeasterly winds which are blowing across the top of the circulation.  Those winds are also causing moderate vertical wind shear and the shear is probably the reason why the band of thunderstorms is displaced northeast of the center of circulation.  It also appears that the western side of the circulation of Tropical Cyclone 04B is also pulling some drier air from over India into the system.  Tropical Cyclone 04B is unlikely to intensify due to the effects of moderate wind shear and drier air.

The upper level ridge is steering Tropical Cyclone 04B toward the north.  On its anticipated track Tropical Cyclone 04B could make landfall near Kolkata in 24 to 30 hours.  The primary risk is locally heavy rain which could cause flooding.  The rain is likely to reach northeastern India a few hours before the center of circulation makes landfall.

Tropical Cyclone Nada Develops Near Sri Lanka

Tropical Cyclone Nada developed over the Bay of Bengal near Sri Lanka.  At 10:00 a.m. EDT on Wednesday the center of Tropical Cyclone Nada was located at latitude 10.1°N and longitude 83.5°E which put it about 295 miles (475 km) east-southeast of Chennai, India.  Nada was moving toward the west-northwest at 14 m.p.h. (23 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.

Microwave satellite imagery indicates that Tropical Cyclone Nada has a well organized, circular low level circulation.  However, most of the thunderstorms are occurring in bands southwest of the center and north of the center.  There are mostly low clouds and showers in the circular bands south and east of the center of circulation.  An upper level ridge over the northern Bay of Bengal is producing easterly winds which are causing moderate vertical wind shear.  The upper level easterly flow is inhibiting the development of thunderstorms east of the center of Tropical Cyclone Nada and those winds may be tilting the circulation toward the west.

The environment surround Tropical Cyclone Nada consists of factors that are favorable for intensification and factors that are unfavorable.  Tropical Cyclone Nada is moving over water where the Sea Surface Temperature is near 29°C.  So, there is sufficient energy in the upper ocean to support intensification.  However the easterly winds in the upper levels are restricting upper level divergence to the east of the tropical cyclone.  Moderate vertical wind shear will limit intensification unless the upper level winds weaken.  If the upper level winds do weaken, then Nada could strengthen given its well developed low level circulation.  Tropical Cyclone Nada only has about 24 to 30 hours before it reaches the coast of India and it will start to weaken once it moves over land.

A subtropical ridge north of Nada is steering the tropical cyclone toward the west-northwest and that general motion is expected to continue.  On its anticipated track the center of Tropical Cyclone Nada will pass north of Sri Lanka and it will approach the southeast coast of India in 24 to 30 hours.  Nada is likely to make a landfall south of Cheannai, India near Pondicherry.  Tropical Cyclone Nada is expected to continue to move to the west and it could emerge over the Arabian Sea in two or three days.

Tropical Cyclone Nada will bring gusty winds and locally heavy rain to northern Sri Lanka and southern India.  Locally heavy rain could cause flooding and mudslides in parts of northern Sri Lanka and Tamil Nadu, Kerala and Karnataka states in India.