Category Archives: Indian Ocean

Tropical Cyclone Habana Expected to Move Westward

Tropical Cyclone Habana is expected to move westward during the upcoming week. At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Habana was located at latitude 17.6°S and longitude 80.4°E which put it about 1150 miles (1850 km) east of Rodrigues. Habana was moving toward the southeast at 5 m.p.h. (8 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 Habana continued to be the equivalent of a major hurricane. A small circular eye reappeared at the center of Habana on infrared satellite images on Sunday afternoon. The eye was surrounded by a ring of strong thunderstorms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Habana. Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone.

The circulation around Tropical Cyclone Habana was small. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Habana. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Habana was 20.6. The Hurricane Size Index (HSI) was 8.5 and the Hurricane Wind Intensity Size Index (HWISI) was 29.1.

Tropical Cyclone Habana will move through an environment capable of supporting a strong tropical cyclone during the next several days. Habana will move over water where the Sea Surface Temperatures will be near 28°C. It will move near the axis of an upper level ridge over the South Indian Ocean. The winds are weaker near the axis of the ridge and there will be little vertical wind shear. Since the core of Habana is so small, the inner end of a rainband could wrap around the existing eye and eyewall. In that case an eyewall replacement cycle would cause fluctuations in the intensity of Tropical Cyclone Habana.

A high pressure system located south of Tropical Cyclone Habana will strengthen during the next few days. That high pressure system will become the dominant weather system steering Habana. When the high pressure system strengthens, it will steer Tropical Cyclone Habana back toward the west. On its anticipated track Habana will pass far to the south of Diego Garcia. Tropical Cyclone Habana is forecast to remain east of Rodrigues during the upcoming week.

Elsewhere over the South Indian Ocean, Tropical Cyclone Iman was speeding away from La Reunion on Sunday afternoon. At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Iman was located at latitude 24.7°S and longitude 58.5°E which put it about 320 miles (515 km) south-southeast of La Reunion. Iman was moving toward the east-southeast at 24 m.p.h. (35 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 990 mb. Tropical Cyclone Habana is forecast to make a transition to an extratropical cyclone during the next 48 hours.

Tropical Cyclone Iman Brings Rain to La Reunion

Tropical Cyclone Iman brought rain to La Reunion and Mauritius on Saturday night. At 7:00 p.m. EST on Saturday the center of Tropical Cyclone Iman was located at latitude 22.6°S and longitude 54.5°E which put it about 105 miles (165 km) south-southwest of La Reunion. Iman was moving toward the east-southeast at 23 m.p.h. (37 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.

An area of low pressure strengthened on Saturday after it moved over the South Indian Ocean east of Madagascar and Meteo France la Reunion designate the system as Tropical Cyclone Iman. The distribution of thunderstorms around Tropical Cyclone Iman was asymmetrical. The strongest thunderstorms were occurring in bands in the eastern half of Iman. Bands in the western half of the tropical cyclone consisted of primarily of showers and thunderstorms. Storms east of the center of circulation generated upper level divergence which pumped mass away to the southeast of the tropical cyclone.

Rainbands on the eastern side of Tropical Cyclone Iman brought gusty winds and locally heavy rain to La Reunion and Mauritius. Heavy rain could cause flash floods in some locations, especially in areas of steeper terrain.

An upper level trough south of Madagascar will steer Tropical Cyclone Iman toward the east-southeast. On its anticipated track Tropical Cyclone Iman will move quickly away to the southeast of La Reunion and Mauritius. Weather conditions in those locations will improve on Sunday.

Tropical Cyclone Iman will move into an environment that will be marginally favorable for intensification during the next 24 hours. Iman will move over water where the Sea Surface Temperatures will be near 27°C. The upper level trough will produce northwesterly winds which will blow toward the top of Iman. Those winds will cause more vertical wind shear and they will inhibit intensification.

Elsewhere over the South Indian Ocean, powerful Tropical Cyclone Habana maintained its intensity south-southeast of Diego Garcia. At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Habana was located at latitude 16.8°S and longitude 79.2°E which put it about 785 miles (1265 km) south-southeast of Diego Garcia. Habana was moving toward the southeast at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 945 mb.

The circulation around Tropical Cyclone Habana was small. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Habana. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Habana was 28.3. The Hurricane Size Index (HSI) was 12.8 and the Hurricane Wind Intensity Size Index (HWISI) was 41.1.

Tropical Cyclone Habana Rapidly Intensifies to Equivalent of Cat. 4 Hurricane

Tropical Cyclone Habana rapidly intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale over the South Indian Ocean on Friday. At 4:00 p.m. EST on Friday the center of Tropical Cyclone Habana was located at latitude 16.1°S and longitude 77.4°E which put it about 695 miles (1120 km) south-southeast of Diego Garcia. Habana was moving toward the east at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 945 mb.

Tropical Cyclone Habana rapidly intensified from the equivalent of a tropical storm to a Category 4 hurricane during the past 24 hours over the South Indian Ocean south of Diego Garcia. A small circular eye with a diameter of 13 miles (20 km) developed at the center of Habana. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Habana. Storms near the core generated strong upper level divergence that pumped mass away from the tropical cyclone.

The circulation around Tropical Cyclone Habana was relatively small. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Habana. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Habana was 28.3. The Hurricane Size Index (HSI) was 9.4 and the Hurricane Wind Intensity Size Index (HWISI) was 37.7.

Tropical Cyclone Habana will move through an environment capable of supporting a strong tropical cyclone during the next 36 hours. Habana will move over water where the Sea Surface Temperatures will be near 28°C. It will move near the axis of an upper level ridge over the South Indian Ocean. The winds are weaker near the axis of the ridge and there will be modest vertical wind shear. Tropical Cyclone Habana could remain the equivalent of a major hurricane during the next 36 hours. Since the core of Habana is so small, the inner end of a rainband could wrap around the existing eye and eyewall. In that case an eyewall replacement cycle would cause Tropical Cyclone Habana to weaken

Tropical Cyclone Habana will move south of a high pressure system over the tropical South Indian Ocean during the next 36 hours. The high will steer Habana toward the east during that time period. On its anticipated track Tropical Cyclone Habana will remain far to the south of Diego Garcia. The high pressure system will weaken with time and a second high pressure system located farther to the south will turn Habana back toward the west early next week.

Tropical Cyclone Habana Develops South of Diego Garcia

Tropical Cyclone Habana developed over the South Indian Ocean south of Diego Garcia on Thursday. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Habana was located at latitude 16.5°S and longitude 73.0°E which put it about 640 miles (1035 km) south of Diego Garcia. Habana was moving toward the east-southeast at 14 m.p.h. (22 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 1000 mb.

An area of low pressure over the South Indian Ocean south of Diego Garcia strengthened on Thursday and the system was designated as Tropical Cyclone Habana. The circulation around Habana was still organizing. A primary rainband wrapped around the eastern and southern sides of the center of circulation. Other bands of showers and thunderstorms were developing. Storms near the center of circulation began to generate upper level divergence which pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 115 miles (185 km) on the eastern side of Tropical Cyclone Habana. Winds to tropical storm force extended out 65 miles (105 km) in the western half of Habana.

Tropical Cyclone Habana will move through an environment favorable for intensification during the next 48 hours. Habana will move over water where the Sea Surface Temperatures will be near 29°C. It will move near the southern part of an upper level ridge. The ridge will produce westerly winds which will blow toward the top of Habana. Those winds will cause some vertical wind shear and the shear will limit the rate at which Tropical Cyclone Habana intensifies.

Tropical Cyclone Habana will move south of a high pressure system over the tropical South Indian Ocean. The high will steer Habana toward the east during the next several days. On its anticipated track Tropical Cyclone Habana will remain far to the south of Diego Garcia.

Elsewhere over the South Indian Ocean Tropical Cyclone Marian was weakening gradually. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Marian was located at latitude 22.1°S and longitude 94.1°E which put it about 680 miles (1100 km) south-southwest of Cocos Island. Marian was moving toward the south-southeast at 9 m.p.h. (15 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.

Tropical Cyclone Marian Spins Southwest of Cocos Island

Tropical Cyclone Marian continued to spin over the South Indian Ocean southwest of Cocos Island on Tuesday. At 10:00 a.m. EST on Tuesday the center of Tropical Cyclone Marian was located at latitude 18.8°S and longitude 90.0°E which put it about 650 miles (1045 km) southwest of Cocos Island. Marian was moving toward the east-southeast at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 958 mb.

The circulation around Tropical Cyclone Marian remained well organized on Tuesday morning. A circular eye with a diameter of 35 miles (55 km) was present at the center of Marian. The eye was surrounded a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Even though the circulation was well organized, satellite images of Tropical Cyclone Marian suggested that it could be starting to weaken. The temperature of the tops of thunderstorms was warming which indicated that those storms were not rising as high in the atmosphere. Microwave satellite imagery depicted breaks forming in the southwestern part of the eyewall of Marian.

Winds to hurricane/typhoon force extended out 65 miles (105 km) from the center of Tropical Cyclone Marian. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Marian was 17.8. The Hurricane Size Index (HSI) was 21.6 and the Hurricane Wind Intensity Size Index (HWISI) was 39.4.

Tropical Cyclone Marian will move into an environment that will be less favorable for tropical cyclones during the next few days. Marian will move over water where the Sea Surface Temperatures will be near 27°C. An upper level trough over the South Indian Ocean will approach Tropical Cyclone Marian from the west. The trough will produce northwesterly winds which will blow toward the top of Marian. Those winds will cause more vertical wind shear. A combination of slightly cooler water and more vertical wind shear will cause Tropical Cyclone Marian to weaken during the next several days.

The upper level trough will begin to steer Tropical Cyclone Marian toward the southeast. On its anticipated track Marian will move farther away from Cocos Island. Tropical Cyclone Marian is forecast to remain west of Western Australia during the next five days.

Tropical Cyclone Marian Intensifies To Equivalent of Major Hurricane

Tropical Cyclone Marian intensified to the equivalent of a major hurricane over the South Indian Ocean southwest of Cocos Island on Sunday. At 10:00 a.m. EST on Sunday the center of Tropical Cyclone Marian was located at latitude 17.5°S and longitude 91.1°E which put it about 520 miles (835 km) southwest of Cocos Island. Marian was moving toward the southwest at 6 m.p.h. (10 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. (235 km/h). The minimum surface pressure was 952 mb.

Tropical Cyclone Marian intensified rapidly into the equivalent of a major hurricane during the past 24 hours. A circular eye with a diameter of 35 miles (55 km) formed at the center of Marian. 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 generated strong upper level divergence that pumped mass away from the tropical cyclone. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Marian.

The area of the strongest winds expanded as Tropical Cyclone Marian intensified rapidly. Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Marian. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Marian was 20.6. The Hurricane Size Index (HSI) was 17.7 and the Hurricane Wind Intensity Size Index (HWISI) was 38.3.

Tropical Cyclone Marian will move through an environment favorable for intensification during the next 12 hours. Marian will move over water where the Sea Surface Temperatures will be near 28°C. It will move under the western portion of an upper level ridge. The upper level winds will be weak during the next 12 hours and there will not be a lot of vertical wind shear. Tropical Cyclone Marian could intensify during the next 12 hours. Marian will move closer to upper level westerly winds in the middle latitudes early next week. The vertical wind shear will increase at that time and Tropical Cyclone Marian will weaken.

Tropical Cyclone Marian will move around the western part of a subtropical high pressure system during the next 36 hours. The high will steer Marian toward the southwest during the next 18 hours. On its anticipated track Tropical Cyclone Marian will move farther away from Cocos Island. After Marian moves around the western end of the high pressure system, the tropical cyclone will start to move toward the southeast..

Tropical Cyclone Marian Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Marian intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean southwest of Cocos Island on Saturday. At 10:00 a.m. EST on Saturday the center of Tropical Cyclone Marian was located at latitude 16.4°S and longitude 93.0°E which put it about 370 miles (595 km) southwest of Cocos Island. Marian was moving toward the southwest at 12 m.p.h. (19 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 976 mb.

Tropical Cyclone Marian continued to exhibit more organization on Saturday. An eye was visible at the center of Marian at times on satellite images. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Marian. Storms near the core generated upper level divergence which pumped mass away from the tropical cyclone. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Marian. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation.

Tropical Cyclone Marian will move through an environment favorable for intensification during the next 24 hours. Marian will move over water where the Sea Surface Temperatures will be near 29°C. It will move under the western portion of an upper level ridge. The upper level winds will be weak during the next 24 hours and there will not be a lot of vertical wind shear. Tropical Cyclone Marian is likely to continue to intensify during the next 24 hours.

Tropical Cyclone Marian will move around the western part of a subtropical high pressure system. The high will steer Marian toward the southwest during the next 36 hours. On its anticipated track Tropical Cyclone Marian will move farther away from Cocos Island. Marian could recurve back toward Australia next week after it moves around the western end of the high pressure system.

Tropical Cyclone Marian Strengthens South of Cocos Island

Tropical Cyclone Marian strengthened south of Cocos Island on Friday. At 10:00 a.m. EST on Friday the center of Tropical Cyclone Marian was located at latitude 14.9°S and longitude 96.4°E which put it about 190 miles (310 km) south of Cocos Island. Marian was moving toward the west at 17 m.p.h. (28 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 979 mb.

The circulation around an area of low pressure over the South Indian Ocean south of Cocos Island exhibited much more organization on Friday and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Marian. Marian organized quickly during the past few hours. An eye was beginning to appear at the center of Marian on infrared satellite images. The inner end of a rainband was wrapping around the eye and the strongest winds were occurring in the developing eyewall. Thunderstorms near the center of Marian generated upper level divergence that pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 200 miles (320 km) in the southern half of Tropical Cyclone Marian. Winds to tropical storm force extended out 120 miles (195 km) in the northern half of Marian.

Tropical Cyclone Marian will move through an environment favorable for intensification during the next 36 hours. Marian will move over water where the Sea Surface Temperatures will be near 29°C. It will move under the northern portion of an upper level ridge. The ridge will produce easterly winds which will blow toward the top of the circulation. However, the winds speeds will be similar at different levels in the atmosphere and there will not be a lot of vertical wind shear. Tropical Cyclone Marian will intensify into the equivalent of a hurricane/typhoon during the next 24 hours.

Tropical Cyclone Marian will move around the northwestern part of a subtropical high pressure system. The high will steer Marian toward the west-southwest during the next several days. On its anticipated track Tropical Cyclone Marian will move farther away from Cocos Island.

Tropical Cyclone Guambe Moves away from Mozambique

Tropical Cyclone Guambe moved away from Mozambique on Saturday. At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Guambe was located at latitude 29.1°S and longitude 38.1°E which put it about 400 miles (645 km) southeast of Maputo, Mozambique. Guambe was moving toward the southeast at 16 m.p.h. (26 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 973 mb.

Tropical Cyclone Guambe appeared to develop concentric eyewalls on Saturday which caused the circulation to weaken. The maximum sustained wind speed decreased when the original, small inner eyewall dissipated. There were fewer thunderstorms around the center of Guambe on Saturday night. The strongest thunderstorms were occurring in bands in the western half of the circulation. Bands in the eastern half of Tropical Cyclone Guambe contained more showers and lower clouds. Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of circulation. Winds to tropical storm force extended out 110 miles (175 km) from the center.

Tropical Cyclone Guambe will move into an environment that will be capable of sustaining a tropical cyclone during the next 24 hours. Guambe will move over water where the Sea Surface Temperatures will be near 26°C, but it will gradually move over colder water. An upper level trough south of Africa will approach Tropical Cyclone Guambe from the west. The trough will produce northwesterly winds which will blow toward the top of Guambe. Those winds will cause more vertical wind shear when they reach Tropical Cyclone Guambe. The combination of more vertical wind shear and colder water will cause the structure of Guambe to being a transition to an extratropical cyclone.

The upper level trough will steer Tropical Cyclone Guambe toward the southeast during the next two days. On its anticipated track Guambe will move farther away from Mozambique. Tropical Cyclone Guambe is forecast to pass well to the south of Madagascar.

Tropical Cyclone Guambe Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Guambe strengthened to the equivalent of a hurricane/typhoon over the Mozambique Channel on Friday. At 4:00 p.m. EST on Friday the center of Tropical Cyclone Guambe was located at latitude 25.4°S and longitude 36.4°E which put it about 260 miles (415 km) east of Maputo, Mozambique. Guambe was moving toward the south-southwest at 4 m.p.h. (6 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 958 mb.

Tropical Cyclone Guambe continued to intensify over the warm water in the Mozambique Channel on Friday. A small circular eye with a diameter of 8 miles (13 km) was present at the center of Guambe. 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 Tropical Cyclone Guambe generated upper level divergence which pumped mass away from the tropical cyclone. Bands of showers and thunderstorms were revolving around the core of Guambe.

The circulation around Tropical Cyclone Guambe was relatively small. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Guambe. Winds to tropical storm force extended out 175 miles (280 km) on the eastern side of the circulation. Winds to tropical storm force extended out 100 miles (160 km) on the western side of the circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Guambe was 16.5. The Hurricane Size Index (HSI) was 11.5 and the Hurricane Wind Intensity Size Index (HWISI) was 28.0.

Tropical Cyclone Guambe will move into an environment that will be favorable for intensification during the next 24 hours. Guambe will move over water where the Sea Surface Temperature is near 29°C. It will move under the center of an upper level ridge. The winds are weak near the center of the ridge and there will be little vertical wind shear. Tropical Cyclone Guambe could strengthen into the equivalent of a major hurricane during the next 24 hours. If the inner end of a rainband wraps around the existing small eye and eyewall, then an eyewall replacement cycle could cause Guambe to weaken.

Tropical Cyclone Guambe will move around the western side of a subtropical high pressure system over the South Indian Ocean. The high will steer Guambe slowly toward the south during the next 24 hours. On its anticipated track Tropical Cyclone Guambe will move parallel to the coast of Mozambique. The center of Guambe is forecast to remain over the Mozambique Channel, but rainbands on the western side of the tropical cyclone could bring gusty winds and heavy rain to parts of the coast of southern Mozambique.