Tag Archives: La Reunion

Tropical Cyclone Francisco Redevelops Near East Coast of Madagascar

After moving slowly westward across the Southwest Indian Ocean for the past few days, Tropical Cyclone Francisco redeveloped near the east coast of Madagascar on Thursday.  At 7:00 a.m. EST on Thursday the center of Tropical Cyclone Francisco was located at latitude 17.9°S and longitude 50.7°E which put it about 90 miles (145 km) east of Toamasina, Madagascar.  Francisco was moving toward the west at 6 m.p.h. (9 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 1004 mb.

Strong vertical wind shear weakened Tropical Cyclone Francisco east of Rodrigues last Thursday, but the lower portion of the circulation remained intact.  The lower level circulation drifted slowly westward during the last seven days and it moved across Mauritius and La Reunion earlier the week.  More thunderstorms began to develop around the lower level circulation on Wednesday, when it moved closer to the east coast of Madagascar.  Bands of showers and thunderstorms began to reform.  Storms near the center of circulation started generating upper level divergence which pumped mass away from the tropical cyclone.  The removal of mass allowed the surface pressure to decrease and the wind speeds began to increase.

Tropical Cyclone Francisco has exhibited greater organization in recent hours.  However, the distribution of thunderstorms was asymmetrical.  Many of the stronger thunderstorms were occurring in bands in the western half of the circulation.  Bands in the eastern half of the circulation consisted primarily of showers and lower clouds.  Francisco was moving under the northern part of an upper level ridge.  The ridge was producing easterly winds which were blowing toward the top of the circulation.  Those winds were causing some vertical wind shear and the shear could be responsible for the asymmetrical distribution of thunderstorms.

Tropical Cyclone Francisco will move through an environment favorable for intensification during the next 6 to 12 hours.  Francisco will move over water where the Sea Surface Temperature is near 28°C.  The upper level ridge will still cause vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Cyclone Francisco will weaken when it moves over Madagascar.

Tropical Cyclone Francisco will move north of a high pressure system over the Southwest Indian Ocean.  The high will steer Francisco toward the west.  On its anticipated track Tropical Cyclone Francisco could make landfall on the east coast of Madagascar in about 12 hours.  Francisco will drop locally heavy rain over parts of central Madagascar.  The heavy rain could cause flash floods in some locations,

Tropical Cyclone Diane Forms North of La Reunion

Tropical Cyclone Diane formed north of La Reunion on Friday.  At 10:00 a.m. EST on Friday the center of Tropical Cyclone Diane was located at latitude 19.3°S and longitude 56.2°E which put it about 110 miles (175 km) north-northeast of St. Denis, La Reunion.  Diane was moving toward the east-southeast at 18 m.p.h. (30 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.

A distinct low level center of circulation developed in an area of low pressure east of Madagascar on Friday and the system was designated as Tropical Cyclone Diane.  The distribution of thunderstorms around Tropical Cyclone Diane was asymmetrical.  Many of the stronger thunderstorms were occurring northwest of the center of circulation.  Bands of showers and thunderstorms were developing east of the center of Diane.  Storms near the center of circulation were beginning to generate upper level divergence which was pumping mass away to the southeast of the tropical cyclone.

Tropical Cyclone Diane will move through an environment somewhat favorable for intensification during the next 24 to 36 hours.  Diane will move over water where the Sea Surface Temperature is near 28°C.  An upper level trough west of Madagascar and an upper level ridge east of Mauritius will interact to produce northwesterly winds which will blow toward the top of the tropical cyclone.  Those winds will cause moderate vertical wind shear which will inhibit intensification.  Tropical Cyclone Diane could intensify slowly during the next 24 to 36 hours.

The upper level trough and upper level ridge will steer Tropical Cyclone Diane toward the east-southeast during the next several days.  On its anticipated track Tropical Cyclone Diane could bring wind and rain to Mauritius within 12 hours.  Locally heavy rain could cause flash floods in some locations.

Tropical Cyclone Calvinia Develops East of Mauritius

Tropical Cyclone Calvinia developed east of Mauritius on Sunday.  At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Calvinia was located at latitude 20.7°S and longitude 58.7°E which put it about 105 miles (165 km) east-southeast of Port Louis, Mauritius.  Calvinia was moving toward the southwest at 6 m.p.h. (10 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 distinct low level center of circulation developed in an area of thunderstorms east of Mauritius on Sunday and the system was designated at Tropical Cyclone Calvinia.  The circulation around Tropical Cyclone Calvinia was asymmetrical.  Many of the stronger thunderstorms were occurring in bands on the eastern side of the circulation.  Bands north and west of the center of Calvinia consisted primarily of showers and lower clouds.  The distributions of strong winds around the tropical cyclone was also asymmetrical.  Winds to tropical storm force extended out 200 miles (320 km) on the eastern side of the circulation.  Winds to tropical storm force only extended out 60 miles (95 km) on the western side.

Tropical Cyclone Calvinia will move through an environment marginally favorable for intensification during the next 24 to 36 hours.  Calvinia will move over water where the Sea Surface Temperature is near 27°C.  It will move east of an upper level trough.  The trough will produce northwesterly winds which will blow toward the top of the circulation.  The winds will cause moderate vertical wind shear and they are probably the reason for the asymmetrical structure of Tropical Cyclone Calvinia.  Calvinia could strengthen during the next several days, but the wind shear is likely to prevent significant intensification.

The upper level trough will steer Tropical Cyclone Calvinia toward the southeast.  On its anticipated track Calvinia will move away from Mauritius and La Reunion.  Since Tropical Cyclone Calvinia will be east of Mauritius, the strongest part of the circulation will remain east of Mauritius and La Reunion.

Tropical Cyclone Joaninha Develops Over Southwest Indian Ocean

Tropical Cyclone Joaninha developed over the Southwest Indian Ocean on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Joaninha was located at latitude 15.7°S and longitude 62.2°E which put it about 260 miles (420 km) north-northwest of Rodrigues, Mauritius.  Joaninha was moving toward the south 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 992 mb.

More thunderstorms developed near the center of a low pressure system over the Southwest Indian Ocean on Friday and the system was designated Tropical Cyclone Joaninha.  The inner end of a band of showers and thunderstorms wrapped around the eastern and southern sides of the center of circulation.  However, the distribution of thunderstorms around Joaninha was asymmetrical.  Several bands of thunderstorms developed in the eastern half of the circulation.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Thunderstorms near the center were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out about 150 miles (240 km) from the center of circulation.

Tropical Cyclone Joaninha will move through an environment favorable for intensification during the next several days.  Joaninha will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Joaninha will continue to intensify during the next 48 to 72 hours.  Joaninha could strengthen into the equivalent of a hurricane/typhoon within 24 hours.  It could be the equivalent of a major hurricane in 48 to 72 hours.

Tropical Cyclone Joaninha will move around the western end of a ridge of high pressure.  The ridge will steer Joaninha toward the south for another day or so.  After it rounds the western end of the ridge, Tropical Cyclone Joaninha will move more toward the southeast.  On its anticipated track Joaninha could approach Rodrigues in about 72 hours.  It could be the equivalent of a major hurricane at that time.

Tropical Cyclone Haleh Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Haleh strengthened into the equivalent of a major hurricane on Monday.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Haleh was centered at latitude 18.9°S and longitude 72.3°E which put it about 800 miles (1290 km) south of Diego Garcia.  Haleh was moving toward the south-southwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 948 mb.

Tropical Cyclone Haley rapidly intensified into the equivalent of a major hurricane during the past 24 hours.  A circular eye was clearly evident on satellite imagery.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Storms near the core of the circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Haleh.  The strongest bands were in the southern half of the circulation.  Bands in the northern half of the circulation consisted primarily of showers and lower clouds.

Winds to hurricane/typhoon force extended out about 50 miles (80 km) from the center of Tropical Cyclone Haleh.  Winds to tropical storm force extended out about 210 miles (330 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Haleh was 22.1.  The Hurricane Size Index (HSI) was 16.0 and the Hurricane Wind Intensity Size Index (HWISI) was 38.1.

Tropical Cyclone Haleh will move through an environment favorable for intensification during the next 24 hours.  Haleh will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds will be weak and there will be little vertical wind shear.  Tropical Cyclone Haleh could intensify during the next day or so.  Eventually, Haleh will move over cooler water and it will start to weaken when that occurs.

Tropical Cyclone Haleh will move around the western end of a subtropical ridge over the South Indian Ocean.  The ridge will steer Haleh toward the south-southwest.  On its anticipated track Tropical Cyclone Haleh is forecast to remain well to the southeast of Mauritius and La Reunion.

Tropical Cyclone Haleh Develops Southeast of Diego Garcia

Tropical Cyclone Haleh developed southeast of Diego Garcia on Saturday.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Haleh was located at latitude 13.5°S and longitude 73.9°E which put it about 435 miles (700 km) south-southeast of Diego Garcia.  Haleh was moving toward the south-southwest at 8 m.p.h. (13 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 981 mb.

The circulation around Tropical Cyclone Haleh organized quickly on Saturday.  An inner rainband wrapped around the southern and western sides of the center of circulation.  Other bands of showers and thunderstorms were revolving around the core of Haleh.  The strongest rainbands were occurring in the eastern half of the circulation.  Rainbands in the western half of the circulation consisted mostly of showers and lower clouds.  Storms near the core of Haleh were generating upper level divergence which was pumping mass away to the southeast of the tropical cyclone.  Winds to tropical storm force extended out about 160 miles (260 km) from the center of circulation.

Tropical Cyclone Haleh will move through an environment favorable for intensification during the next several days.  Haleh will move over water where the Sea Surface Temperature is near 29°C.  An upper level trough to the west of Tropical Cyclone Haleh will produce northwesterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Cyclone Haleh is forecast to intensify into the equivalent of a hurricane/typhoon.

Tropical Cyclone Haleh will move around the northwestern part of a subtropical ridge over the South Indian Ocean.  The ridge will steer Haleh toward the southwest during the next few days.  On its anticipated track Tropical Cyclone Haleh will remain well to the south of Diego Garcia.

Tropical Cyclone Gelena Brings Wind and Rain to Rodrigues

Tropical Cyclone Gelena brought wind and rain to Rodrigues on Saturday.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Gelena was located at latitude 20.5°S and longitude 63.7°E which put it about 55 miles (90 km) southeast of Rodrigues, Mauritius.  Gelena was moving toward the east-southeast at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 959 mb.

Tropical Cyclone Gelena was the equivalent of a major hurricane when it moved past Rodrigues.  Winds to hurricane/typhoon force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Gelena was 20.6.  The Hurricane Size Index (HSI) was 15.9 and the Hurricane Wind Intensity Size Index (HWISI) was 36.5.

The northeastern part of the eyewall of Tropical Cyclone Gelena appeared to cross Rodrigues.  Winds to hurricane/typhoon force may have occurred when that part of the eyewall moved over the island.  Winds to tropical storm force will continue for a few more hours until Gelena moves farther away from Rodrigues.  Conditions on Rodrigues should gradually improve on Sunday while Tropical Cyclone Gelena moves farther away.  Gelena will weaken as it moves over colder water.

Elsewhere over South Indian Ocean, Tropical Cyclone Funani made a transition to an extratropical cyclone.  At 4:00 p.m. EST the center of Tropical Cyclone Funani was located at latitude 31.9°S and longitude 77.4°E which put it about 1390 miles (2245 km) southeast of Mauritius.  Funani was moving toward the southeast at 28 m.p.h. (45 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 996 mb.

Tropical Cyclone Gelena Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Gelena strengthened into the equivalent of a major hurricane on Friday.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Gelena was located at latitude 16.8°S and longitude 56.9°E which put it about 265 miles (425 km) north of Port Louis, Mauritius.  Gelena was moving toward the southeast at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 155 m.p.h. (205 km/h).  The minimum surface pressure was 953 mb.

The circulation around Tropical Cyclone Gelena strengthened and grew larger on Friday.  An eye appeared intermittently at the center of Gelena on satellite imagery.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in the ring of storms.  More bands of showers and thunderstorms were revolving around the core of the circulation.  Winds to hurricane/typhoon force extended out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 175 miles (280 km) from the center.

The Hurricane Intensity Index (HII) for Tropical Cyclone Gelena was 23.6.  The Hurricane Size Index (HSI) was 17.3 and the Hurricane Wind Intensity Size Index (HWISI) was 40.9.  Those indices indicated that tropical Cyclone Gelena was capable of causing major regional damage.

Tropical Cyclone Gelena will move through an environment somewhat favorable for intensification for another 12 to 24 hours.  Gelena will move over water where the Sea Surface Temperature is near 29°C.  An upper level trough near Madagascar will produce westerly winds which are blowing toward the top of Tropical Cyclone Gelena.  Those winds will produce some vertical wind shear and they will inhibit upper level divergence toward the western periphery of Gelena.  The wind shear will inhibit intensification, but Tropical Cyclone Gelena could strengthen on Saturday.

Tropical Cyclone Gelena will move south of a subtropical ridge.  The ridge will steer Gelena in a southeasterly direction.  On its anticipated track Tropical Cyclone Gelena will pass north of Mauritius.  However, Gelena could approach Rodrigues within 36 hours.  Tropical Cyclone Gelena could bring strong winds and heavy rain to Rodrigues.

Elsewhere over the southern Indian Ocean, Tropical Cyclone Funani was speeding toward colder water.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Funani was located at latitude 26.3°S and longitude 73.4°E which put it about 805 miles (1295 km) east-southeast of Rodrigues.  Funani was moving toward the southeast at 28 m.p.h. (45 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 977 mb.

Stronger Tropical Cyclone Gelena Moves Toward Rodrigues

A stronger Tropical Cyclone Gelena moved toward Rodrigues on Thursday.  At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Gelena was located at latitude 14.8°S and longitude 54.5°E which put it about 340 miles (550 km) north-northwest of Port Louis, Mauritius.  Gelena was moving toward the south-southeast at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 972 mb.

Tropical Cyclone Gelena strengthened into the equivalent of a hurricane/typhoon on Thursday.  An eye cleared at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Storms near the core were generating strong upper level divergence which was pumping mass away from the tropical cyclone.  Several bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Gelena.  Winds to hurricane/typhoon force extended out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out about 140 miles (225 km) from the center.

Tropical Cyclone Gelena will move through an environment favorable for intensification.  Gelena will move over water where the Sea Surface Temperature is near 29°C.  It will move through an environment where the upper level winds are weak and the there will be little vertical wind shear.  Tropical Cyclone Gelena will intensify during the next 24 to 36 hours and it could strengthen rapidly at times.  Gelena will likely become the equivalent of a major hurricane during the next 36 hours.

Tropical Cyclone Gelena will move south of a subtropical ridge which will steer the tropical cyclone toward the southeast.  On its anticipated track the core of Gelena will pass north of Mauritius in about 24 hours.  Tropical Cyclone Gelena could approach Rodrigues in 36 to 48 hours.  Gelena could be the equivalent of a major hurricane at that time.

Elsewhere over the Southwest Indian Ocean Tropical Cyclone Funani intensified into the equivalent of a major hurricane as it moved away from Rodrigues.  At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Funani was located at latitude 22.2°S and longitude 69.3°E which put it about 430 miles (690 km) east-southeast of Rodrigues, Mauritius.  Funani was moving toward the southeast at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 950 mb.

Tropical Cyclone Funani Brushes Rodrigues, Gelena Also a Threat

The western edge of Tropical Cyclone Funani brushed Rodrigues on Wednesday and Tropical Cyclone Gelena also posed a threat to the island.  At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Funani was located at latitude 18.1°S and longitude 65.1°E which put it about 515 miles (830 km) east-northeast of Port Louis, Mauritius and about 155 miles (250 km) northeast of Rodrigues.  Funani was moving toward the southeast 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 968 mb.

Tropical Cyclone Funani rapidly intensified into the equivalent of a hurricane/typhoon on Wednesday.  An eye was apparent on satellite images.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Storms near the core of Funani generated strong upper level divergence which pumped mass away from the tropical cyclone.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Funani.  There were more bands in the eastern half of the circulation.  Winds to hurricane/typhoon force extended out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out about 140 miles (225 km) from the center.

Tropical Cyclone Funani will be in an environment favorable for intensification for another 12 to 24 hours.  Funani will move over water where the Sea Surface Temperature is near 29°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Funani could strengthen into the equivalent of a major hurricane during the next 24 hours.  Funani will move over cooler water at the end of the week and it will start to weaken in a less favorable environment.

Tropical Cyclone Funani is moving south of a subtropical ridge which is steering the tropical cyclone toward the southeast.  A general motion toward the southeast is expected to continue during the next few days.  On its anticipated track the core of Tropical Cyclone Funani will pass east of Rodrigues.  Surface observations on Rodrigues indicate that the western portion of Funani is dropping rain on that island, but winds are generally blowing at less than tropical storm force.

Tropical Cyclone Gelena also poses a threat to Rodrigues.  At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Gelena was located at latitude 12.5°S and longitude 53.2°E which put it about 535 miles (865 km) north-northwest of Port Louis, Mauritius.  Gelena was moving toward the south-southwest at 3 m.p.h. (5 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 987 mb.

Tropical Cyclone Gelena also intensified rapidly on Wednesday.  A tiny, pinhole eye was apparent on satellite imagery.  A thin ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Storms near the core of Gelena were generating upper level divergence which was pumping mass away from the tropical cyclone.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Gelena.  There were more bands in the northern half of the circulation.  Winds to tropical storm force extended out about 90 miles (150 km) from the center of circulation.

Tropical Cyclone Gelena will also move through an environment favorable for intensification.  Gelena will move over water where the Sea Surface Temperature is near 29°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Gelena is likely to intensify into the equivalent of a hurricane/typhoon during the next 24 hours.  Gelena could strengthen into the equivalent of a major hurricane during the next several days.

Although Tropical Cyclone Gelena is currently weaker and smaller than Tropical Cyclone Funani, it may pose a greater risk to Rodrigues.  Gelena is forecast to pass closer to Rodrigues than Funani will pass and Gelena may be the equivalent of a major hurricane when it moves near Rodrigues.  Gelena could bring strong winds and heavy rain to Rodrigues in about 48 hours.