Tag Archives: Mauritius

Tropical Cyclone Fantala Reorganizes Northeast of Madagascar

Tropical Cyclone Fantala reorganized northeast of Madagascar on Tuesday.  At 8:00 p.m. EDT on Tuesday the center of Tropical Cyclone Fantala was located at latitude 10.0°S and longitude 52.0°E which put it about 240 miles (385 km) northeast of Antsirañana, Madagascar.  Fantala was moving toward the east-southeast at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 135 m.p.h. (220 km/h).  The minimum surface pressure was 952 mb.

The core of the circulation of Tropical Cyclone Fantala became more organized on Tuesday.  A ring of strong thunderstorms surrounded a circular eye that was visible on satellite imagery.  It did still appear that some drier air was wrapping around the eastern and southern sides of the circulation, but the drier air did not appear to be spiraling into the center of the circulation.  Upper level divergence appeared to increase throughout the day.

The environment around Tropical Cyclone Fantala is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is not much vertical wind shear.  The only inhibiting factor is the presence of a band of drier air on the eastern and southern sides of the circulation.  Given the improved organization of the core of the circulation, Tropical Cyclone Fantala could intensify further on Wednesday.

A ridge north of Fantala is steering the Tropical Cyclone toward the east-southeast and that general motion is expected to continue for another day or two.  A new subtropical ridge could develop southwest of Fantala and turn it back toward the west later this week.  Tropical Cyclone Fantala could still have an impact on northern Madagascar in a few days.

Tropical Cyclone Fantala Stalls and Weakens North of Madagascar

Tropical Cyclone Fantala stalled north of Madagascar on Monday and it weakened below Category 5 on the Saffir-Simpson Scale.  At 8:00 p.m. EDT on Monday the center of Tropical Cyclone Fantala was located at latitude 9.2°S and longitude 49.6°E which put it about 200 miles (320 km) north of Antsirañana, Madagascar.  Fantala was nearly stationary.  The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 165 m.p.h. (265 km/h).  The minimum surface pressure was 933 mb.

The structure of the circulation of Tropical Cyclone Fantala deteriorated on Monday.  An eye was no longer visible in satellite imagery and the ring of thunderstorms that was around the eye appeared to have a gap on the east side.  There were still bands of thunderstorms spiraling around the outer portion of the circulation.  However, it appeared that some drier air may have been pulled into the northeastern part of Fantala.  Thunderstorms were still generating upper level divergence, but it was mainly to the south of the tropical cyclone.  The upper level divergence pumped out less mass than the amount of mass that converged in the lower levels and the surface pressure rose about 20 mb on Monday.

The environment around Tropical Cyclone Fantala contains a mixture of favorable and unfavorable features.  Fantala is over water where the Sea Surface Temperatures are near 29°C.  Upper level winds are blowing a little more strongly from the northeast, but the vertical wind shear is still not too significant.  Fantala does seem to be pulling in some drier air into its circulation.  The tropical cyclone is nearly stationary and its strong winds may be mixing some cooler water to the surface.  Drier air and cooler water would reduce the energy available to drive the circulation of Fantala and it is likely to weaken further on Tuesday.

Fantala is in an area where the steering currents are weak and it may not move much during the next 12 to 24 hours.  Eventually, a ridge is expected to develop northeast of Fantala and start to steer the tropical cyclone toward the southeast.  On its anticipated track the core of strongest winds would pass north of Madagascar.  However, there is still uncertainty about the future track of Fantala and it could still have an impact on northern Madagascar.

 

Tropical Cyclone Fantala Reaches Cat. 5 North of Madagascar

Tropical Cyclone Fantala continued to intensify on Sunday and it reached the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Sunday the center of Tropical Cyclone Fantala was located at latitude 9.7°S and longitude 50.5°E which put it about 190 miles (305 km) north-northeast of Antsirañana, Madagascar.  Fantala was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 205 m.p.h. (335 km/h).  The minimum surface pressure was 911 mb.

Fantala is an extremely well organized tropical cyclone.  There is a solid ring of thunderstorms surrounding a clear eye.  Other bands of thunderstorms spiral into the core of the circulation.  Hurricane force winds extend out about 30 miles (50 km) south of the center.  The thunderstorms are generating enough upper level divergence to cause the surface pressure to decrease to 911 mb.

Fantala is a very powerful tropical cyclone.  The Hurricane Intensity Index (HII) is 40.4, the Hurricane Size (HSI) is 10.5, and the Hurricane Wind Intensity Size Index (HWISI) is 50.9.

The environment around Tropical Cyclone Fantala is very favorable.  It is over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  Fantala could intensify a little more, but it is likely near its maximum intensity.  Any increase in the speed of the upper level winds would generate more vertical wind shear and start to weaken Fantala.

A subtropical ridge southwest of the tropical cyclone is steering Fantala toward the west-northwest.  That general motion is expected to continue for another 12 to 24 hours.  Guidance from numerical models predicts that in a day or so a second ridge located northeast of Fantala will begin to steer the tropical cyclone back to the southeast.  There is variability in the location and sharpness of the turn to the southeast.  If there is a sharp turn to the southeast, the core of Fantala could remain north of Madagascar.  If the turn occurs later and/or is more gradual the core of Fantala could come closer to the northern end of Madagascar.

Tropical Cyclone Fantala is a very dangerous storm.  It would be capable of causing catastrophic damage if it were to make landfall.

Tropical Cyclone Fantala Almost Equal to Cat. 5 Hurricane

Tropical Cyclone Fantala intensified further on Saturday and it is almost the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  At 8:00 p.m. EDT on Saturday the center of Tropical Cyclone Fantala was located at latitude 11.1°S and longitude 53.4°E which put it about 620 miles north of St. Denis, La Reunion.  Fantala was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 922 mb.

Tropical Cyclone Fantala increased in both intensity and size again on Saturday.  Hurricane force winds now extend out about 60 miles (95 km) south of the center of circulation.  The Hurricane Intensity Index (HII) for Fantala is 33.3.  The Hurricane Size Index (HSI) is 18.7 and the Hurricane Wind Intensity Size Index (HWISI) is 52.0.

The circulation of Tropical Cyclone Fantala is very well organized.  It has a clearly visible eye on satellite imagery.  The eye is surrounded by a ring of strong thunderstorms.  Additional bands of thunderstorms are rotating around the core of the circulation.  The thunderstorms are generating strong upper level divergence which is pumping out mass in all directions.

The environment around Tropical Cyclone Fantala is favorable.  It is over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Fantala could intensify a little more during the next 24 hours.  If one of the rainbands wraps around the existing eye, and eyewall replacement cycle could cause fluctuations of intensity.

A subtropical ridge southwest of Fantala is steering the tropical cyclone toward the west-northwest.  That general motion is expected to continue for another 24 to 36 hours.  In a day or so Fantala will move into an area where the steering currents are weaker and it could slow down or stall.  Eventually a northwesterly flow is forecast turn Tropical Cyclone Fantala back toward the southeast.  However, guidance from numerical models differs on when and where the southeasterly turn will occur.

On its anticipated track Tropical Cyclone Fantala could be near the northern end of Madagascar in a day or two.  The current size and intensity of Fantala means that it could produce regional significant damage if it were to hit land.  The future track of Fantala will determine if the tropical cyclone has an impact on Madagascar.

Tropical Cyclone Fantala Intensifies to Equivalent of Cat. 4 Hurricane

Tropical Cyclone Fantala continued to get stronger on Friday and it is now the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Fantala was located at latitude 12.4°S and longitude 57.6°E which put it about 530 miles (860 km) north of Port Louis, Mauritius.  Fantala was moving toward the west at 8 m.p.h. (13 km/h).  The maximum sustained wind speed  was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 926 mb.

Tropical Cyclone Fantala is very well organized.  There is a ring of strong thunderstorms surrounding a well formed eye.  Other spiral bands are rotating near the core of the circulation.  Thunderstorms are generating upper level divergence which is pumping out large amounts of mass and allowing the surface pressure to decrease further.  The Hurricane Intensity Index (HII) for Tropical Cyclone Fantala is 31.6.  The Hurricane Size Index (HSI) is 18.4 and the Hurricane Wind Intensity Size Index (HWISI) is 50.0.

Fantala continues to exist in an environment favorable for intensification.  It is over water where the Sea Surface Temperature is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  Fantala could become the equivalent of a Category 5 hurricane during the next 24 hours.  Fantala appeared to go through an eyewall replacement cycle on Thursday and further cycles could produce additional fluctuations in intensity.

A subtropical ridge located southwest of Fantala is steering the tropical cyclone toward the west.  Movement toward the west or west-northwest is expected during the next 24 to 48 hours.  On its anticipated track Tropical Cyclone Fantala could be northeast of the northern tip of Madagascar by the end of the weekend.  Fantala is a powerful, dangerous tropical cyclone and it would be capable of doing regional serious damage if it made landfall.

Tropical Cyclone Fantala Gets Bigger and Stronger

Tropical Cyclone Fantala grew in size and intensity on Wednesday.  At 8:00 p.m. EDT on Wednesday the center of Tropical Cyclone Fantala was located at latitude 12.7°N and longitude 64.2°E which put it about 700 miles (1130 km) northeast of Port Louis, Mauritius.  Fantala was moving toward the west at 10 m.p.h. (16 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. (200 km/h).  The minimum surface pressure was 956 mb.  The Hurricane Intensity Index (HII) was 17.8, the Hurricane Size Index (HSI) was 14.6 and the Hurricane Wind Intensity Size Index (HWISI) was 32.4.

Both the organization and size of the circulation of Fantala increased on Wednesday.  A complete eyewall formed around an eye at the center of the tropical cyclone.  Other well formed bands of thunderstorms developed and wrapped around the core of Fantala.  The structure of the tropical cyclone is much more symmetrical and there are thunderstorms in all quadrants of the circulation.  Winds to hurricane force extended out 35 miles (55 km) from the center of circulation.  Thunderstorms around the core of Fantala generated upper level divergence which pumped out mass and allowed the surface pressure to decrease.

Tropical Cyclone Fantala is an environment favorable for further intensification.  Fantala is over water where the Sea Surface Temperature is near 30°C.  The upper level winds are light and there is very little vertical wind shear.  The structure of Fantala will allow it to use the energy from the ocean very efficiently.  Fantala is likely to continue to intensify on Thursday and it could become the equivalent of a major hurricane.  As Fantala gets stronger, concentric eyewalls could develop and the resulting eyewall replacement cycles could produce fluctuations in intensity.

A subtropical ridge located to the south of Fantala is steering it toward the west and that general steering motion is expected to continue during the next several days.  On its anticipated track Fantala will pass north of Mauritus and La Reunion during the weekend.  Tropical Cyclone Fantala could be near northern Madagascar in a few days.

Tropical Cyclone Fantala Intensifies and Heads Slowly West

Tropical Cyclone Fantala intensified into the the equivalent of a hurricane/typhoon as it headed slowed west across the South Indian Ocean on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Cyclone Fantala was located at latitude 12.8°S and longitude 68.5°E which put it about 465 miles (755 km) south-southwest of Diego Garcia.  Fantala was moving toward the west-northwest at 5 m.p.h. (8 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 975 mb.

The core of Tropical Cyclone Fantala continued to get better organized on Tuesday.  The primary rainband wrapped entirely around the center of circulation and a small eye appeared intermittently on some satellite imagery.  Thunderstorms around the center of circulation began to produce more upper level divergence and high clouds could be seen fanning out in all directions.  The upper level divergence pumped out mass and allowed the surface pressure to decrease.

Fantala is a small tropical cyclone.  Tropical storm force winds only extend about 100 miles (160 km) from the center of circulation.  The Hurricane Size Index for Tropical Cyclone Fantala is only 8.1.

Tropical Cyclone Fantala is in an environment that appears to be mostly favorable for intensification.  It is over water where the Sea Surface Temperature is near 30°C.  The upper level winds are light and there is not much vertical wind shear.  The only possible negative factor is the presence of some drier air around the periphery of the circulation.  Tropical Cyclone Fantala is likely to intensify further and its small size could allow it to intensify rapidly at times.  Tropical Cyclone Fantala could become the equivalent of a major hurricane later this week.

A subtropical ridge located south of Fantala is steering the tropical cyclone toward the west and that general motion is expected to continue for the next several days.  On its anticipated track Tropical Cyclone Fantala could pass north of La Reunion in a few days.  Fantala could be northeast of Madagascar in four or five days.

Tropical Cyclone Fantala Forms South of Diego Garcia

A well organized center of circulation developed within a small area of thunderstorms south of Diego Garcia on Monday and the system was designated Tropical Cyclone Fantala.  At 8:00 p.m. EDT on Monday the center of Tropical Cyclone Fantala was located at latitude 13.0°S and longitude 70.8°E which put it about 420 miles (675 km) south-southwest of Diego Garcia.  Fantala was moving toward the west at 9 m.p.h. (14 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 989 mb.

The circulation of Tropical Cyclone is still organizing.  A primary rainband is wrapping around the southern and western sides of the center of circulation.  Most of the thunderstorms are near or in the primary rainband.  There are few thunderstorms east of the center of circulation.  The thunderstorms are generating upper level outflow to the west side of the circulation.

The environment is favorable for further intensification.  Fantala is over water where the Sea Surface Temperatures are near 30°C.  An upper level ridge south of Fantala is generating light easterly winds over the core of the circulation.  The easterly winds are producing a little vertical wind shear.  The shear is strong enough to contribute to the asymmetrical distribution of thunderstorms, but it is not strong enough to prevent intensification.  Tropical Cyclone Fantala could become the equivalent of a hurricane/typhoon within 24 hours.

A subtropical ridge south of Fantala is expected to steer the tropical cyclone in a general westerly direction during the next few days.  On its anticipated track Tropical Cyclone Fantala could be northeast of La Reunion later this week.

Eyewall Replacement Cycle Weakens Tropical Cyclone Bansi

At 7:00 p.m. EST on Tuesday the center of Tropical Cyclone Bansi was located at latitude 17.4°S and longitude 58.2°E which put it about 200 miles north-northeast of Port Louis, Mauritius.  Bansi was moving toward the east-southeast at 3 m.p.h.  The maximum sustained wind speed was 130 m.p.h. and it was estimated there could be wind gusts to 160 m.p.h.  The estimated minimum surface pressure was 944 mb.

An outer rain band wrapped completely around the existing eyewall of Tropical Cyclone Bansi to create concentric eyewalls.  As the low level convergence became concentrated on the outer eyewall, the inner eyewall began to weaken.  This resulted in a reduction of the maximum sustained wind speed and a rise in the minimum surface pressure.  Satellite imagery indicates that most of the inner eyewall has dissipated, but some of it still remains.  The strongest winds are now occurring in the outer eyewall.  The eyewall replacement cycle also resulted in a larger circulation.  Bansi is still over warm Sea Surface Temperatures and the upper level winds are relatively weak.  So, some reintensification is possible during the next 24 hours, but it is always challenging to predict intensity changes after an eyewall replacement cycle.  As Bansi moves to higher latitudes, the Sea Surface Temperature will decrease and wind shear will increase.  So, Bansi is expected to weaken later this week.

Bansi remains in an area of weak steering winds.  As a result, it is moving slowly toward the east-southeast.  A subtropical ridge is expected to strengthen in about 24 hours and begin to steer Bansi southeastward at an increasing speed.  The projected track is expected to keep the core of Bansi northeast of Mauritius.

 

Tropical Cyclone Bansi Intensifying Rapidly North of La Reunion

A tropical cyclone has intensified rapidly north of La Réunion during the past 24 hours.  At 1:00 p.m. EST on Sunday the center of Tropical Cyclone Bansi was located at latitude 17.1°N and longitude 55.1°E which put it about 300 miles north of Saint Denis, La Réunion and about 250 miles northwest of Port Louis, Mauritius.  Bansi was moving toward the south-southeast at 5 m.p.h.  The maximum sustained wind speed was 75 m.p.h. and there were wind gusts to 90 m.p.h.  The minimum surface pressure was estimated to be 974 mb.

The circulation around Bansi organized rapidly on Sunday and it exhibits a symmetrical shape with a well developed eye at its center.  The circulation is small, but it has well developed upper level outflow to pump out mass.  Bansi is over Sea Surface Temperatures that are warmer than 30°C which provide plenty of energy to intensify the circulation further.  Bansi could intensify rapidly for another 24 hours and become a very strong tropical cyclone as it passes near Mauritius.

Bansi is being steered to the south-southeast by a ridge of high pressure.  The ridge is expected to continue to steer Bansi in a general southeasterly direction, although there could be short-term jogs to the east-southeast or south-southeast.  The anticipated track could bring Bansi near Mauritius in 48-72 hours.