Tag Archives: SH03

Tropical Cyclone Gaja Forms Over Bay of Bengal

Tropical Cyclone Gaja formed over the Bay of Bengal on Sunday.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Gaja was located at latitude 12.9°N and longitude 86.7°E which put it about 500 miles (805 km) east of Chennai, India.  Gaja was moving toward the west-southwest at 8 m.p.h. (13 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 1002 mb.

An area of low pressure moving over the Bay of Bengal strengthened on Sunday and the India Meteorological Department classified the system as Tropical Cyclone Gaja.  The circulation around Tropical Cyclone Gaja is still organizing.  There is a distinct low level center of circulation.  A short band of thunderstorms is west and north of the center.  Several other bands of showers and thunderstorms are developing in other parts of Tropical Cyclone Gaja.  One stronger band is east of the center of circulation and another stronger band is southeast of the center.  Storms near the center are beginning to generate upper level divergence which will pump mass away from the tropical cyclone.

Tropical Cyclone Gaja will move through an environment somewhat favorable for intensification during the next 48 hours.  Gaja will move over water where the Sea Surface Temperature is near 29°C.  It will move south of an upper level ridge.  The ridge will produce easterly winds which will blow toward the top of the circulation.  The winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Cyclone Gaja will intensify and it could be nearly equivalent to a hurricane/typhoon in two or three days.

The upper level ridge will steer Tropical Cyclone Gaja in a generally west-southwesterly direction.  On its anticipated track Tropical Cyclone Gaja will approach the coast of southern India in about 72 hours.  Gaja could be nearly the equivalent of a hurricane/typhoon at that time.

Elsewhere, over the South Indian Ocean Tropical Cyclone Alcide still was moving slowly east of the northern end of Madgascar and Tropical Cyclone Bouchra developed between Diego Garcia and Cocos Island.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Alcide was located at latitude 12.3°N and longitude 51.9°E which put it about 170 miles (275 km) east of Antisiranana, Madagascar.  Alcide was moving toward the northwest 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 997 mb.

At 4:00 p.m. EDT on Sunday the center of Tropical Cyclone Bouchra was located at latitude 5.4°S and longitude 89.1°E which put it about 700 miles (1130 km) northwest of Cocos Island, Australia.  Bouchra was moving toward the east at 2 m.p.h. (3 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 999 mb.

Tropical Cyclone Alcide Stalls East of Madgascar

Tropical Cyclone Alcide stalled east of northern Madagascar on Friday.  At 4:00 p.m. EDT on Friday the center of Tropical Cyclone Alcide was located at latitude 13.4°N and longitude 53.1°E which put it about 250 miles (400 km) east of Antisiranana, Madagascar.  Alcide was moving toward the south at 4 m.p.h. (6 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 95 m.p.h. (155 km/h).  The minimum surface pressure was 978 mb.

Tropical Cyclone Alcide weakened during the past 36 hours.  An eye is no longer apparent on visible satellite images, although an eyelike feature persists on microwave satellite images.  There are breaks in the ring of thunderstorms surrounding the eye.  Winds to hurricane/typhoon force are occurring in the broken ring of storms.  Alcide moved very slowly during the past day or so.  Its slow movement may have allowed its winds to mix cooler water to the surface of the ocean.  If there is cooler water at the surface, then there is less energy available to support the circulation of Tropical Cyclone Alcide.  The circulation of Alcide remains relatively small.  Winds to tropical storm force extend out about 100 miles (160 km) from the center of circulation.

Tropical Cyclone Alcide is in an area where the steering currents are weak.  Alcide could meander over the same area for another day or so.  If it remains over the same cooler water, then Alcide will slowly weaken further.  As the circulation gets weaker, thunderstorms will not rise as high into the atmosphere and Tropical Cyclone Alcide will be steered by winds at lower levels.  If Alcide eventually moves over warmer water, and the upper level winds are not too strong, then new thunderstorms could develop.

Tropical Cyclone Alcide is not forecast to move much during the next 24 hours.  In a day or so the winds in the lower and middle troposphere are forecast to begin to steer Alcide in a more westerly direction.  On its anticipated track Tropical Cyclone Alcide could move closer to northern Madagascar on Sunday.

Tropical Cyclone Alcide Rapidly Intensifies Into Equivalent of Hurricane/Typhoon

Tropical Cyclone Alcide rapidly intensified into the equivalent of a hurricane/typhoon east of northern Madagascar on Wednesday.  At 10:00 a.m. EDT on Wednesday the center of Tropical Cyclone Alcide was located at latitude 10.6°S and longitude 55.7°W which put it about 675 miles (975 km) north of Port Louis, Mauritius.  Alcide was moving toward the west-southwest at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (170 km/h).  The minimum surface pressure was 972 mb.

The circulation around Tropical Cyclone Alcide organized rapidly during the past 24 hours.  An eye formed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Alcide.  Storm near the core were generating upper level divergence which was pumping mass away from the tropical cyclone.

The circulation around Tropical Cyclone Alcide is relatively small.  Winds to hurricane/typhoon force extend out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extend out about 80 miles (130 km) from the center.

Tropical Cyclone Alcide will move through an environment capable of supporting further intensification during the next 48 hours.  Alcide will move over water where the Sea Surface Temperature is near 27°C.  It will move near the western end of an upper level ridge.  The ridge will produce easterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear will not prevent intensification.  Tropical Cyclone Alcide could strengthen to the equivalent of a major hurricane during the next day or two.

The upper level ridge will steer Tropical Cyclone Alcide in a west-southwesterly direction.  On its anticipated track Alcide would stay north of Mauritius and La Reunion.  Tropical Cyclone Alcide could be east of northern Madagascar in a few days.

Tropical Cyclone Alcide Forms North of Mauritius

Tropical Cyclone Alcide formed north of Mauritius on Tuesday.  At 10:00 a.m. EDT on Tuesday the center of Tropical Cyclone Alcide was located at latitude 9.7°S and longitude 58.9°E which put it about 740 miles (1190 km) north of Port Louis, Mauritius.  Alcide was moving toward the west-southwest at 10 m.p.h. (16 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 999 mb.

A distinct center of circulation consolidated in an area of thunderstorms over the South Indian Ocean and the system was designated as Tropical Cyclone Alcide.  The circulation around Alcide was slowly becoming better organized.  The inner end of a band of thunderstorms was wrapping around the western side of the center of circulation.  Several other bands were developing south and west of the center.  Bands north and east of the center consisted primarily of showers and lower clouds.  Storms near the center of circulation were starting to generate upper level divergence which was pumping mass away from the core of the tropical cyclone.

Tropical Cyclone Alcide will move through an environment that will support intensification.  Alcide will move over water where the Sea Surface Temperature is near 27.5°C.  It will move around the northwestern side of an upper level ridge.  The ridge will produce easterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear which will slow the rate of intensification, but the winds are not likely to be strong enough to prevent intensification.  Tropical Cyclone Alcide could strengthen into the equivalent of a hurricane/typhoon during the next 48 to 72 hours.

The upper level ridge will steer Tropical Cyclone Alcide slowly toward the west-southwest during the next two or three days.  On its anticipated track Alcide could be northeast of Madagascar in a few days.  It could be the equivalent of a hurricane/typhoon at that time.

Tropical Low Forms Over Western Australia

A Tropical Low formed over Western Australia on Monday and a Tropical Cyclone Watch was issued for a portion of the coast.  At 2:00 p.m. EST on Monday the center of the Tropical Low was located at latitude 15.9°S and longitude 126.1°E which put it about 135 miles (220 km) west-southwest of Wyndham, Australia.  It was moving toward the southwest a 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 20 m.p.h. (30 km/h) and there were wind gusts to 50 m.p.h. (85 km/h).  The minimum surface pressure was 1005 mb.  The Australia Bureau of Meteorology has issued a Tropical Cyclone Watch for the portion of the coast of Western Australia from Kuri Bay to Wallal Downs including Broome.

The circulation of the Tropical Low is still organizing.  There is a broad low level center of circulation, but there are not many showers and thunderstorms near the center.  There are numerous bands of showers and storms developing in bands on the eastern and western peripheries of the circulation.  The strongest wind gusts are occurring in those storms.  The lack of storms near the center of circulation is keeping the system from generating much upper level divergence.

The core of the Tropical Low is likely to remain over land for another 12-24 hours, which will inhibit the organization of the circulation.  When the center moves off the coast and over the South Indian Ocean, it will move into an environment favorable for intensification.  The Sea Surface Temperature of the water west of the coast of Western Australia is near 30°C.  The Tropical Low is moving north of the axis of a subtropical ridge.  The ridge is producing easterly winds which are blowing toward the top of the circulation, but there is not a lot of vertical wind shear.  The Tropical Low is likely to strengthen when it moves over water and it could intensify rapidly if a more concentrated center of circulation develops.

A subtropical ridge is current steering the Tropical Low toward the southwest, but a general motion toward the west-southwest is expected during the next 24 to 48 hours.  The Tropical Low will reach the western end of the ridge in about two days and then it will turn more toward the south.  On its anticipated track the center of the Tropical Low is expected to move off the coast between Kuri Bay and Derby on Tuesday.  The center is forecast to pass near Cape Leveque and then turn south toward Wallal Downs.

Elsewhere over the South Indian Ocean, Tropical Cyclone Ava continued to swirl near southern Madagascar and stronger Tropical Cyclone Irving was passing well to the south of Diego Garcia.  At 4:00 p.m. EST on Monday the center of Tropical Storm Ava was located at latitude 27.7°S and longitude 46.8°E which put it about 180 miles (295 km) south of Farodofay, Madagascar.  Ava was moving toward the west-southwest at 17 m.p.h. (27 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.

At 4:00 p.m. EST on Monday the center of Tropical Cyclone Irving was centered at latitude 19.6°S and longitude 76.1°E which put it about 875 miles (1415 km) south-southeast of Diego Garcia.  Irving was moving toward the west-southwest at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 960 mb.  Tropical Cyclone Irving was the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale.

Tropical Cyclone Ava Drops Heavy Rain on Madagascar

Tropical Cyclone Ava dropped heavy rain over Madagascar on Saturday.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Ava was located at latitude 21.4°S and longitude 48.2°E which put it about 70 miles (110 km) north-northwest of Mananjary, Madagascar.  Ava was moving toward the south-southeast at 11 m.p.h. (17 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.

Tropical Cyclone Ava weakened into the equivalent of a tropical storm during the day it spent moving over Madagascar.  The strongest winds were occurring in bands of thunderstorms over the water.  The center made landfall on Friday near Toamasina.  The center then passed near Moramanga, Anosibe An’ala, and Marolambo.  There is still a distinct center of circulation and several bands of showers and thunderstorms are revolving around the center.  Some of the storms dropped heavy rain over parts of Madagascar.  There was stronger rising motion in places where the winds blew up the sides of mountains and the rainfall was heavier in those locations.  The potential for flooding exists in places that received heavy rain.

The center of Tropical Cyclone Ava is likely to move back over the water of the South Indian Ocean during the next few hours.  Tropical Cyclone Ava will move into an environment that is favorable for intensification when it moves back over water.  The Sea Surface Temperature of the water east of Madagascar is near 28°C.  Ava is moving under the axis of an upper level ridge and the upper level winds are relatively weak.  So, there is not a lot of vertical wind shear.  Tropical Cyclone Ava is likely to strengthen once the center moves back over water.

Tropical Cyclone Ava is moving around the western end of a subtropical ridge which is steering Ava toward the south-southeast.  The ridge is forecast to steer Tropical Cyclone Ava toward the south for another day or two.  When Tropical Cyclone Ava moves farther to the south in about 48 hours, an upper level trough will cause northwesterly winds, which will start to steer the tropical cyclone toward the east-southeast.  On its anticipated track the center of Tropical Cyclone Ava is expected to move off the coast of Madagascar near Mananjary in a few hours.

Elsewhere over the South Indian Ocean, Tropical Cyclone Irving was strengthening east-southeast of Diego Garcia.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Irving was located at latitude 13.3°S and longitude 87.5°E which put it about 1145 miles (1845 km) east-southeast of Diego Garcia.  Irving was moving toward the west-southwest at 13 m.p.h. (21 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 991 mb.

Satellite imagery suggested that Tropical Cyclone Irving could be strengthening rapidly.  A primary rainband was wrapping around the center of circulation.  An eye appeared to be forming at the center of Irving.  Tropical Cyclone Irving will move through an environment favorable for intensification.  Irving is likely to intensify into the equivalent of a hurricane/typhoon while it passes well to the south of Diego Garcia during the next several days.

Strong Tropical Cyclone Ava Makes Landfall in Madagascar

Strong Tropical Cyclone Ava made landfall on the east coast of Madagascar near Toamasina on Friday.  At 10:00 a.m. EDT on Friday the center of Tropical Cyclone Ava was located near 18.0°S and longitude 49.2°E which put it near Toamasina.  Ava was moving toward the west-southwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 959 mb.  Tropical Cyclone Ava was the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale.

Tropical Cyclone Ava intensified rapidly during the past 12 hours and it was still intensifying when it made landfall on the coast of Madagascar.  There was a well defined circular eye at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of the circulation.  Thunderstorms in the core of Tropical Cyclone Ava were generating strong upper level divergence which was pumping away mass and allowed the surface pressure to decrease rapidly.  Winds to hurricane/typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 180 miles (290 km) from the center.

The Hurricane Intensity Index (HII) for Tropical Cyclone Ava was 17.8.  The Hurricane Size Index (HSI) was 17.6 and the Hurricane Wind Intensity Size Index (HWISI) was 35.4.  Those indices indicate that Tropical Cyclone Ava is capable of causing regional serious damage.  The core of Tropical Cyclone Ava passed over Toamasina and there is likely to be serious wind damage in that city.  Heavy rain was falling in parts of eastern Madagascar and floods could occur.  Tropical Cyclone Ava could produce a storm surge of 10 feet (3 meters) south of where the center made landfall, because the strong winds will be blowing the water toward the coast.

Tropical Cyclone Ava will weaken while the center moves over land in eastern Madagascar.  However, the rest of the environment is favorable for a tropical cyclone.  The Sea Surface Temperature off the east coast of Madagascar is near 28°C.  The upper level winds are weak and there is little vertical wind shear.  If the inner core of Tropical Cyclone Ava remains intact, then Ava could intensify again when the center moves back over the South Indian Ocean in a day or so.

Tropical Cyclone Ava is moving around the western end of a subtropical ridge which is steering the tropical cyclone toward the west-southwest.  Ava will start to move toward the south when it reaches the end of the ridge in a few hours.  On its anticipated track Tropical Cyclone Ava is forecast to move just inland of the east coast of Madagascar.  Ava is forecast to move back off the coast in 24 to 36 hours.  Tropical Cyclone Ava is capable of causing serious damage along the central east coast of Madagascar.

Tropical Cyclone Ava Strengthens East of Madagascar

Tropical Cyclone Ava intensified east of Madagascar on Thursday.  At 4:00 p.m. EST on Thursday the center of Tropical Cyclone Ava was located at latitude 17.4°S and longitude 50.8°E which put it about 125 miles (205 km) east-northeast of Toamasina, Madagascar.  Ava was moving toward the west-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 980 mb.

Tropical Cyclone Ava exhibited the classic structure of a tropical cyclone on Thursday.  A clear eye was evident at the center of circulation on microwave satellite imagery.  The eye was surrounded by a nearly complete ring of showers and thunderstorms.  Spiral bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Ava.  Storms in the core of Ava were generating strong upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out about 140 miles (225 km) from the center of circulation.

Tropical Cyclone Ava will move through an environment favorable for intensification on Friday.  Ava will move over water where the Sea Surface Temperature is near 28.5°C.  Tropical Cyclone Ava is moving near the western end of an upper level ridge, but the upper level winds are weak and there is not much vertical wind shear.  Warm water and little vertical wind shear will allow Tropical Cyclone Ava to intensify during the next 24 hours.  Ava should strengthen into the equivalent of a hurricane/typhoon on Friday.

Tropical Cyclone Ava is moving around the western end of a subtropical ridge, which has been steering Ava mostly toward the west.  Tropical Cyclone Ava is forecast to move more toward the southwest on Friday as it nears the western end of the ridge.  On its anticipated track the center of Tropical Cyclone Ava will move close to the east coast of Madagascar near Toamasina in 18 to 24 hours.  When Ava reaches the western end of the ridge in about 24 hours, it will start to move more toward the south.

Tropical Cyclone Ava will bring strong winds and locally heavy rain to the east coast of Madagascar.  The winds will be strong enough to do damage and they could generate a storm surge at the coast.  Rain is already falling on parts of eastern Madagascar and more heavy rain will create the potential for floods.

Tropical Cyclone 03S Forms East of Madagascar

Tropical Cyclone 03S formed east of Madagascar on Tuesday.  At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone 03S was centered at latitude 15.5°S and longitude 53.2°E which put it about 330 miles (530 km) east-northeast of Toamasina, Madagascar.  It was moving a little south of due west at 9 m.p.h. (15 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 996 mb.

A well defined center of circulation developed within a cluster of thunderstorms passing north of La Reunion on Tuesday.  A primary rainband wrapped around the center of circulation and the system exhibited the characteristics of a tropical cyclone.  The innermost end of the primary  rainband wrapped tightly around the eastern side of the center of circulation, while the rest of the band coiled around the northern and western parts of the tropical cyclone.  Additional bands of showers and thunderstorms were forming outside the core of the system.  Thunderstorms near the center of circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.

Tropical Cyclone 03S will be moving through an environment favorable for intensification.  It will move over water where the Sea Surface Temperature is near 28.5°C.  Tropical Cyclone 03S is in a region where the upper level winds are weak and there is not much vertical wind shear.  Warm water and little shear will allow Tropical Cyclone 03S to intensify and it could intensify rapidly.  The system is likely to strengthen into the equivalent of a hurricane/typhoon within 36 hours.

Tropical Cyclone 03S is moving along the northwestern periphery of a subtropical ridge.  The ridge is currently steering the system toward the west.  However, Tropical Cyclone 03S is likely to move more toward the southwest when it reaches the western end of the ridge.  On its anticipated track Tropical Cyclone 03S could approach the east coast of Madagascar in 24 to 36 hours.

Tropical Cyclone 03S is likely to intensify into the equivalent of a hurricane/typhoon before it reaches Madagascar.  It will bring strong gusty winds to eastern Madagascar.  The outer rainbands on the western side of Tropical Cyclone 03S are already dropping heavy rain on parts of eastern Madagascar.  Continued heavy could create dangerous floods in some locations.

Tropical Cyclone 03S Moving West of Australia

A tropical cyclone designated 03S moved farther west of Australia and weakened on Saturday.  Tropical Cyclone 03S moved across northern Australia as a low pressure system last week before move off the coast near Broome.  After the center of the low moved over the South Indian Ocean thunderstorms developed near the core of the system and the Australian Bureau of Meteorology classified it as a tropical low.  The tropical low strengthened into the equivalent of a tropical storm on Friday night, but the Australian Bureau of Meteorology did not give the system a name.

At 7:00 p.m. EST on Saturday the center of Tropical Cyclone 03S was located at latitude 19.5°S and longitude 109.8°E which put it about 335 miles (540 km) northwest of Learmonth, Australia.  Tropical Cyclone 03S was moving toward the west at 12 m.p.h. (19 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 994 mb.

Tropical Cyclone 03S has a well defined low level circulation but the distribution of thunderstorms is asymmetrical.  Most of the stronger thunderstorms are forming in bands west of the center of circulation.  There are also bands in the eastern half of the circulation but they consist primarily of low clouds and rain showers.  Strong easterly winds in the upper levels are shearing the tops off of any thunderstorms that develop in the eastern part of the circulation.  The easterly winds are also inhibiting upper level divergence to the east of the center.

Tropical Cyclone 03S will move into an environment that will be unfavorable for intensification.  Tropical Cyclone 03S is moving over water where the Sea Surface Temperature is near 26°C, but it will move over cooler water during the next several days.  An upper level ridge centered over Australia is generating easterly winds which are blowing across the top of the tropical cyclone.  The easterly winds are causing moderate vertical wind shear and are responsible for the asymmetrical distribution of thunderstorms.  Tropical Cyclone 03S is likely to weaken slowly during the next several days.

A subtropical ridge will continue to steer Tropical Cyclone 03S to the west during the next few days.  On its anticipated track Tropical Cyclone 03S is expected to move farther away from Western Australia as it weakens.