Tag Archives: SH22

Tropical Cyclone Halima Spins Southeast of Diego Garcia

Tropical Cyclone Halima continued to spin over the South Indian Ocean southeast of Diego Garcia on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Tropical Cyclone Halima was located at latitude 19.9°S and longitude 81.7°E which put it about 1090 miles (1755 km) southeast of Diego Garcia. Halima was moving toward the northwest at 10 m.p.h (16 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 Halima maintained its intensity on Tuesday as it continued to meander southeast of Diego Garcia. An upper level trough over the South Indian Ocean produced west-northwesterly winds that blew toward the top of Halima’s circulation. Those winds caused moderate vertical wind shear and they affected the distribution of thunderstorms in Tropical Cyclone Halima. The strongest thunderstorms were occurring in a band southeast of the center of Halima. Other scattered thunderstorms were occurring in bands in the eastern half of Tropical Cyclone Halima. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 75 miles (120 km) from the center of circulation.

Tropical Cyclone Halima will move through an environment that will continue to be unfavorable for intensification during the next 24 hours. Halima will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough will continue to produce west-northwesterly winds that will create moderate vertical wind shear. The wind shear will cause Tropical Cyclone Halima to weaken during the next 24 hours.

Tropical Cyclone Halima will move around the eastern end of a high pressure system over the South Indian Ocean during the next 24 hours. The high pressure system will steer Halima toward the north. On its anticipated track Tropical Cyclone Halima will remain far southeast of Diego Garcia during the next 24 hours.

Tropical Cyclone Halima Meanders Southeast of Diego Garcia

Tropical Cyclone Halima meandered slowly over the South Indian Ocean southeast of Diego Garcia on Monday. At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Halima was located at latitude 21.8°S and longitude 82.5°E which put it about 1195 miles (1930 km) southeast of Diego Garcia. Halima was moving toward the east-northeast at 5 m.p.h (8 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 Halima maintained its intensity on Monday while it meandered over the South Indian Ocean southeast of Diego Garcia. An upper level trough continued to cause moderate vertical wind shear, but the direction of the upper level winds changed from northwesterly to westerly. The change in the wind direction altered the distribution of thunderstorms in Halima’s circulation. The strongest thunderstorms were occurring in a band southeast of the center of Tropical Cyclone Halima. Other bands of thunderstorms were in the eastern half of Halima. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 90 miles from the center of circulation.

Tropical Cyclone Halima will move through an environment that will continue to be unfavorable for intensification during the next 24 hours. Halima will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough will continue to produce westerly winds that will create moderate vertical wind shear. The wind shear will cause Tropical Cyclone Halima to weaken during the next 24 hours.

Tropical Cyclone Halima will move around the eastern end of a high pressure system over the South Indian Ocean during the next 24 hours. The high pressure system will steer Halima slowly toward the north. On its anticipated track Tropical Cyclone Halima will remain far southeast of Diego Garcia during the next 24 hours.

Tropical Cyclone Halima Continues to Weaken

Tropical Cyclone Halima continued to weaken over the South Indian Ocean south of Diego Garcia on Sunday. At 11:00 p.m. EDT on Sunday the center of Tropical Cyclone Halima was located at latitude 21.7°S and longitude 80.7°E which put it about 1120 miles (1805 km) south-southeast of Diego Garcia. Halima was moving toward the southeast at 8 m.p.h (13 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.

An upper level trough over the South Indian Ocean continued to produce northwesterly winds that blew toward the top of Halima’s circulation. Those winds caused moderate vertical wind shear. The wind shear caused Tropical Cyclone Halima to continue to weaken. The inner end of a rainband wrapped around the center of Halima’s circulation, but the distribution of thunderstorms remained asymmetrical. Most of the thunderstorms were occurring in bands in the southern half of Tropical Cyclone Halima. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation.

Tropical Cyclone Halima will move through an environment that will continue to be unfavorable for intensification during the next 24 hours. Halima will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough will continue to produce moderate vertical wind shear. The wind shear will cause Tropical Cyclone Halima to continue to weaken during the next 24 hours.

The upper level trough will steer Tropical Cyclone Halima toward the east during the next 24 hours. On its anticipated track Tropical Cyclone Halima will move farther away from Diego Garcia. If the thunderstorms in the southern half of Halima’s circulation dissipate, then the tropical cyclone will only exist in the lower levels of the atmosphere. If that happens, then the winds in the lower levels could turn Tropical Cyclone Halima back toward the north.

Tropical Cyclone Halima Weakens South of Diego Garcia

Tropical Cyclone Halima weakened over the South Indian Ocean south of Diego Garcia on Saturday. At 11:00 p.m. EDT on Saturday the center of Tropical Cyclone Halima was located at latitude 20.0°S and longitude 76.4°E which put it about 890 miles (1440 km) south-southeast of Diego Garcia. Halima was moving toward the southeast at 17 m.p.h (28 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 981 mb.

Tropical Cyclone Halima weakened on Saturday when it moved into an environment that included more vertical wind shear. An upper level trough over the South Indian Ocean produced northwesterly winds that blew toward the top of Halima’s circulation. Those winds produced moderate vertical wind shear. The wind shear affected the structure of Tropical Cyclone Halima. The former small eyewall became fragmented. In addition, the stronger thunderstorms were occurring in bands in the southern half of Halima’s circulation. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. Winds to hurricane/typhoon force extended out 15 miles (25 km) from the center of Tropical Cyclone Halima. Winds to tropical storm force extended out 105 miles (165 km) from the center of circulation.

Tropical Cyclone Halima will move through an environment that will continue to be unfavorable for intensification during the next 36 hours. Halima will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough will continue to produce moderate vertical wind shear. The wind shear will cause Tropical Cyclone Halima to continue to weaken during the next 36 hours.

The upper level trough will continue to steer Tropical Cyclone Halima toward the southeast during the next 24 hours. On its anticipated track Tropical Cyclone Halima will move farther away from Diego Garcia.

Tropical Cyclone Halima Rapidly Intensifies to Equivalent of a Major Hurricane

Tropical Cyclone Halima rapidly intensified to the equivalent of a major hurricane over the South Indian Ocean south of Diego Garcia on Friday. At 11:00 a.m. EDT on Friday the center of Tropical Cyclone Halima was located at latitude 14.6°S and longitude 73.4°E which put it about 495 miles (795 km) south of Diego Garcia. Halima was moving toward the south-southwest at 6 m.p.h (10 km/h). The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (265 km/h). The minimum surface pressure was 918 mb.

Tropical Cyclone Halima rapidly intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale during the past 24 hours. A small circular eye with a diameter of 10 miles (16 km) was at the center of Halima’s circulation. 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 Halima. Storms near the core of the circulation generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone. The removal of mass allowed the surface pressure to decrease rapidly.

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

Tropical Cyclone Halima will move through an environment capable of supporting a strong tropical cyclone during the next 24 hours. Halima will move over water where the Sea Surface Temperatures are near 28˚C. It will move under 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. Tropical Cyclone Halima could continue to intensify during the next 24 hours. If the inner end of a rainband wraps around the existing small eye and eyewall, then concentric eyewalls could form. Concentric eyewalls would be the beginning of an eyewall replacement cyclone that would cause Halima to weaken.

Tropical Cyclone Halima will move around the western end of a high pressure system over the South Indian Ocean during the next 24 hours. The high pressure system will steer Halima toward the south. On its anticipated track Tropical Cyclone Halima will continue to move farther away from Diego Garcia.

Tropical Cyclone Halima Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Halima strengthened to the equivalent of a hurricane/typhoon over the South Indian Ocean south of Diego Garcia on Thursday. At 11:00 a.m. EDT on Thursday the center of Tropical Cyclone Halima was located at latitude 13.2°S and longitude 74.3°E which put it about 435 miles (700 km) south-southeast of Diego Garcia. Halima was moving toward the west at 6 m.p.h (10 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 979 mb.

Tropical Cyclone Halima intensified to the equivalent of a hurricane/typhoon on Thursday. A small circular eye with a diameter of 10 miles (16 km) formed at the center of Halima’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Other strong thunderstorms were occurring in bands in the western half of Tropical Cyclone Halima. Bands in the eastern half of the circulation consisted primarily of showers and lower clouds. Storms near the center of Halima’s circulation generated upper level divergence that pumped mass away from the tropical cyclone. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Tropical Cyclone Halima. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

Tropical Cyclone Halima will move through an environment favorable for intensification during the next 36 hours. Halima will move over water where the Sea Surface Temperatures are near 28˚C. It will move under 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. Tropical Cyclone Halima will intensify during the next 36 hours and it could strengthen to the equivalent of a major hurricane.

Tropical Cyclone Halima will move around the western end of a high pressure system over the South Indian Ocean during the next 36 hours. The high pressure system will steer Halima toward the south. On its anticipated track Tropical Cyclone Halima will move farther away from Diego Garcia.

Tropical Cyclone Halima Forms South of Diego Garcia

Tropical Cyclone Halima formed south of Diego Garcia on Wednesday. At 11:00 a.m. EDT on Wednesday the center of Tropical Cyclone Halima was located at latitude 13.4°S and longitude 75.7°E which put it about 485 miles (780 km) south-southeast of Diego Garcia. Halima was moving toward the west-southwest 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 997 mb.

The circulation around a low pressure system over the South Indian Ocean south of Diego Garcia strengthened on Wednesday and the system was designated at Tropical Cyclone Halima. More thunderstorms formed west of the center of Halima’s circulation. The strongest thunderstorms were occurring in bands in the western half of Tropical Cyclone Halima. Bands in the eastern half of the circulation consisted primarily of showers and lower clouds. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 90 miles (145 km) from the center of Halima.

Tropical Cyclone Halima will move through an environment favorable for intensification during the next 36 hours. Halima will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the northern part of an upper level ridge over the South Indian Ocean. The ridge will produce easterly winds that will blow toward the top of Halima’s circulation. Those winds will cause some vertical wind shear, but the shear will not be enough to prevent intensification. Tropical Cyclone Halima will intensify during the next 36 hours and it could strengthen to the equivalent of a hurricane/typhoon.

Tropical Cyclone Halima will move around the western end of a high pressure system over the South Indian Ocean during the next 36 hours. The high pressure system will steer Halima toward the south. On its anticipated track Tropical Cyclone Halima will move farther away from Diego Garcia.

Elsewhere over the South Indian Ocean, Tropical Cyclone Charlotte weakened gradually northwest of Australia. At 11:00 a.m. EDT on Wednesday the center of Tropical Cyclone Charlotte was located at latitude 20.4°S and longitude 107.6°E which put it about 430 miles (695 km) west-northwest of Learmonth, Australia. Charlotte was moving toward the south-southwest at 13 m.p.h (20 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 979 mb.

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..