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Tropical Cyclone Herman Weakens Southeast of Cocos Islands

Tropical Cyclone Herman weakened over the South Indian Ocean southeast of the Cocos Islands on Saturday. At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Herman was located at latitude 19.9°S and longitude 106.7°E which put it about 865 miles (1395 km) southeast of the Cocos Islands. Herman was moving toward the south-southwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 978 mb.

Tropical Cyclone Herman weakened on Saturday. An upper level trough over the South Indian Ocean produced northwesterly winds that blew toward the top of Herman’s circulation. Those winds caused moderate vertical wind shear and the wind shear caused Tropical Cyclone Herman to weaken. An eye was no longer evident on satellite images of Herman. The inner end of a rainband still wrapped around the southern and western sides of the center of Herman’s circulation. The circulation around Tropical Cyclone Herman was small. Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of Herman. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Tropical Cyclone Herman will move through an environment that will be unfavorable for intensification during the next 36 hours. Herman will move over water where the Sea Surface Temperatures are near 26˚C. However, the upper level trough over the South Indian Ocean will continue to produce northwesterly winds that will blow toward the top of Herman’s circulation. Those winds will continue to cause moderate vertical wind shear and the wind shear will cause Tropical Cyclone Herman to weaken. Since Herman’s circulation is small, the tropical cyclone could weaken rapidly at times.

Tropical Cyclone Herman will move north of high pressure system over the South Indian Ocean. The high pressure system will steer Herman toward the west during the next 36 hours. On its anticipated track, Tropical Cyclone Herman will remain far to the south of the Cocos Islands.

Tropical Cyclone Herman Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Herman strengthened to the equivalent of a major hurricane over the South Indian Ocean northwest of Australia during Thursday night. At 11:00 a.m. EDT on Friday the center of Tropical Cyclone Herman was located at latitude 18.0°S and longitude 106.8°E which put it about 780 miles (1260 km) east-southeast of Cocos Islands. Herman was moving toward the southeast at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h). The minimum surface pressure was 947 mb.

Tropical Cyclone Herman strengthened to the equivalent of a major hurricane over the South Indian Ocean during Thursday night. A small circular eye was present at the center of Herman’s circulation. A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Herman. Storms near the center generated upper level divergence that pumped mass away to the southeast of the tropical cyclone.

The circulation around Tropical Cyclone Herman was small. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Herman. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Herman was 23.6. The Hurricane Size Index (HSI) was 8.6 and the Hurricane Wind Intensity Size Index (HWISI) was 32.2. Tropical Cyclone Herman was similar in size and intensity to Hurricane Dennis when Dennis made landfall in northwest Florida in 2005.

Tropical Cyclone Herman will move through an environment that will become unfavorable for intensification during the next 24 hours. Herman will move over water where the Sea Surface Temperatures are near 28˚C. However, an upper level trough will approach Tropical Cyclone Herman from the west. The upper level trough will produce northwesterly winds that will get stronger during the next 24 hours. Those stronger winds will blow toward the top of Herman’s circulation and the vertical wind shear will increase. More vertical wind shear will cause Tropical Cyclone Herman to weaken. Since Herman’s circulation is small, the tropical cyclone could weaken rapidly when the wind shear increases.

The upper level trough will steer Tropical Cyclone Herman toward the south-southeast during the next 24 hours. On its anticipated track Tropical Cyclone Herman will move farther away from Cocos Islands. When the stronger vertical wind shear causes Herman to weaken, it will be steered by the winds closer to the surface. Those winds will steer Tropical Cyclone Herman toward the west during the weekend.

Tropical Cyclone Herman Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Herman rapidly intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean northwest of Australia on Thursday. At 5:00 p.m. EDT on Thursday the center of Tropical Cyclone Herman was located at latitude 16.5°S and longitude 106.0°E which put it about 665 miles (1070 km) east-southeast of Cocos Islands. Herman was moving toward the south-southeast at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h). The minimum surface pressure was 959 mb.

Tropical Cyclone Herman rapidly intensified to nearly the equivalent of a major hurricane over the South Indian Ocean on Thursday. A small circular eye was present at the center of Herman’s circulation. A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Herman. Storms near the center generated upper level divergence that pumped mass away to the southeast of the tropical cyclone.

The circulation around Tropical Cyclone Herman was small. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Herman. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Herman was 19.2. The Hurricane Size Index (HSI) was 9.4 and the Hurricane Wind Intensity Size Index (HWISI) was 28.6. Tropical Cyclone Herman was similar in size and intensity to Hurricane Zeta when Zeta made landfall in Louisiana in 2020.

Tropical Cyclone Herman will move through an environment that will become unfavorable for intensification during the next 24 hours. Herman will move over water where the Sea Surface Temperatures are near 28˚C. However, an upper level trough will approach Tropical Cyclone Herman from the west. The upper level trough will produce northwesterly winds that will get stronger during the next 24 hours. Those stronger winds will blow toward the top of Herman’s circulation and the vertical wind shear will increase. More vertical wind shear will cause Tropical Cyclone Herman to weaken.

The upper level trough will steer Tropical Cyclone Herman toward the south-southeast during the next 24 hours. On its anticipated track Tropical Cyclone Herman will move farther away from Cocos Islands. When the stronger vertical wind shear causes Herman to weaken, it will be steered by the winds closer to the surface. Those winds will steer Tropical Cyclone Herman toward the west during the weekend.

Tropical Cyclone Herman Strengthens Northwest of Australia

Tropical Cyclone Herman strengthened over the South Indian Ocean northwest of Australia during Wednesday night. At 5:00 a.m. EDT on Thursday the center of Tropical Cyclone Herman was located at latitude 15.5°S and longitude 105.1°E which put it about 570 miles (920 km) east-southeast of Cocos Islands. Herman was moving toward the southeast at 10 m.p.h. (16 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 985 mb.

Tropical Cyclone Herman strengthened over the South Indian Ocean northwest of Australia during the past 24 hours. The inner end of a rainband wrapped completely around the center of Herman’s circulation. A small circular eye formed at the center of circulation. A ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Herman. Storms near the center generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. Winds to tropical storm force extended out 65 miles (105 km) from the center of Herman’s circulation.

Tropical Cyclone Herman will move through an environment that will become unfavorable for intensification during the next 24 hours. Herman will move over water where the Sea Surface Temperatures are near 28˚C. However, an upper level trough will approach Tropical Cyclone Herman from the west. The upper level trough will produce northwesterly winds that will get stronger during the next 24 hours. Those stronger winds will blow toward the top of Herman’s circulation and the vertical wind shear will increase. More vertical wind shear will cause Tropical Cyclone Herman to weaken.

The upper level trough will steer Tropical Cyclone Herman toward the southeast during the next 24 hours. On its anticipated track Tropical Cyclone Herman will move farther away from Cocos Islands. When the stronger vertical wind shear causes Herman to weaken, it will be steered by the winds closer to the surface. Those winds will steer Tropical Cyclone Herman toward the west during the end of the week and the weekend.

Tropical Cyclone Herman Forms Northwest of Australia

Tropical Cyclone Herman formed over the South Indian Ocean northwest of Australia on Wednesday morning. At 5:00 a.m. EDT on Wednesday the center of Tropical Cyclone Herman was located at latitude 13.9°S and longitude 101.5°E which put it about 300 miles (480 km) east-southeast of Cocos Islands. Herman was moving toward the southwest at 12 m.p.h. (19 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 997 mb.

An area of low pressure over the South Indian Ocean east-southeast of Cocos Islands strengthened on Wednesday morning and the the Australian Bureau of Meteorology designated the system as Tropical Cyclone Herman. The inner end of a rainband wrapped around the western side of the center of Herman’s circulation. The strongest winds were occurring in the part of the band west of the center. Other bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Herman. 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 160 miles (260 km) from the center of Herman’s circulation.

Tropical Cyclone Herman will move through an environment favorable for intensification during the next 24 hours. Herman will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western end of an upper level ridge over the eastern part of the South Indian Ocean. The ridge will produce northerly winds that will blow toward the top of Herman’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Tropical Cyclone Herman is likely to strengthen during the next 24 hours. An upper level trough will approach Herman from the west on Thursday. The trough will cause the upper level winds to get stronger and the vertical wind shear will increase. More vertical wind shear will cause Tropical Cyclone Herman to weaken.

Tropical Cyclone Herman will move around the southwestern part of a high pressure system over the eastern South Indian Ocean. The high pressure system will steer Herman toward the southeast during the next 24 hours. On its anticipated track Tropical Cyclone Herman will move away from Cocos Islands. When Herman weakens later this week, it will be steered by the winds closer to the surface. Those winds will steer Tropical Cyclone Herman toward the west during the end of the week and the weekend.

Tropical Cyclone Lucas Brushes New Caledonia

Tropical Cyclone Lucas brushed New Caledonia on Tuesday night. At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Lucas was located at latitude 22.2°S and longitude 167.0°E which put it about 75 miles (120 km) east-northeast of Noumea, New Caledonia. Lucas was moving toward the south at 15 m.p.h. (24 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 991 mb.

Tropical Cyclone Lucas brought gusty winds and locally heavy rain to parts of southern New Caledonia on Tuesday night. Lucas weakened before it reached New Caledonia. An upper level trough east of Australia produced strong northwesterly winds that blew toward the top of Tropical Cyclone Lucas. Those winds caused strong vertical wind shear and they blew the tops off of thunderstorms around the center of Lucas. Drier air wrapped around the northern side of the tropical cyclone, which caused some of the outer rainbands to weaken as well. Tropical Cyclone Lucas was the equivalent of a tropical storm when it moved near southern New Caledonia. Winds to tropical storm force extended out 150 miles (240 km) from the center of Lucas.

Since many of the stronger thunderstorms in the circulation around Tropical Cyclone Lucas have weakened, the system will be steered by winds lower in the atmosphere. A high pressure system north of New Zealand will steer Lucas slowly toward the west during the next several days. On its anticipated track Tropical Cyclone Lucas will continue to bring gusty winds and locally heavy rain to parts of southern New Caledonia for another 24 hours.

Tropical Cyclone Lucas Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Lucas strengthened to the equivalent of a hurricane/typhoon over the Coral Sea on Monday. At 10:00 a.m. EST on Monday the center of Tropical Cyclone Lucas was located at latitude 16.1°S and longitude 163.1°E which put it about 495 miles (800 km) north-northeast of Noumea, New Caledonia. Lucas was moving toward the southeast at 22 m.p.h. (35 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 Lucas intensified north of New Caledonia on Monday. A microwave satellite image showed a small eye forming at the center of Lucas. The inner end of a rainband wrapped around the northern and eastern sides of the developing eye. Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Lucas. The strongest bands were in the eastern half of the circulation. Storms near the center of circulation generated upper level divergence which pumped mass away to the southeast of the tropical cyclone. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Lucas. Winds to tropical storm force extended out 170 miles (280 km) from the center of circulation.

Tropical Cyclone Lucas will move through an environment only marginally favorable for intensification. Lucas will move over water where the Sea Surface Temperature is near 29°C. An upper level trough east of Australia will produce northwesterly winds which blow toward the top of the tropical cyclone. Those winds will cause moderate vertical wind shear and they will inhibit intensification. The vertical wind shear could be strong enough to prevent intensification of Tropical Cyclone Lucas even though it will move over warm water.

Tropical Cyclone Lucas will move around the southwestern part of a high pressure system during the next 24 hours. That high pressure system will steer Lucas toward the southeast during the next day or so. A second high pressure system over the South Pacific Ocean will start to steer Tropical Cyclone Lucas more toward the south later on Tuesday. On its anticipated track Lucas could approach New Caledonia within 36 hours.

Tropical Cyclone Bina Develops Northwest of Fiji

Tropical Cyclone Bina developed northwest of Fiji on Sunday. At 10:00 a.m. EST on Sunday the center of Tropical Cyclone Bina was located at latitude 14.0°S and longitude 175.7°E which put it about 315 miles (510 km) northwest of Labasa, Fiji. Bina was moving toward the southeast at 16 m.p.h. (26 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 994 mb.

As Tropical Cyclone Ana was moving away from Fiji, Tropical Cyclone Bina developed northwest of that nation. A low pressure system northwest of Fiji strengthened on Sunday and the Fiji Meteorological Service designated the system as Tropical Cyclone Bina. More thunderstorms formed near the center of Bina. Those storms generated upper level divergence which pumped mass away from the tropical cyclone. The circulation around Tropical Cyclone Bina was small. Winds to tropical storm force only extended out 80 miles (130 km) from the center of Bina.

Tropical Cyclone Bina will move through an environment marginally favorable for intensification during the next 24 hours. Bina will move over water where the Sea Surface Temperature is near 28°C. An upper level trough east of Australia will produce northwesterly winds which blow toward the top of the tropical cyclone. Those winds will cause moderate vertical wind shear and they will inhibit intensification. Tropical Cyclone Bina will likely maintain its intensity during the next 24 hours.

The upper level trough will steer Tropical Cyclone Bina toward the southeast during the next 36 hours. On its anticipated track Bina could reach Vanua Levu within 18 hours. Tropical Cyclone Bina will bring gusty winds and locally heavy rain to Fiji during the next 36 hours. The stormy conditions will make efforts on Viti Levu and Vanua Levu to recover from Tropical Cyclone Ana more difficult. Heavy rain could make floods caused by Ana to become worse.

Elsewhere over the Southwest Pacific Ocean, Tropical Cyclone Ana was moving away from Fiji and Tropical Cyclone Lucas was strengthening over the Coral Sea. At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Ana was located at latitude 19.9°S and longitude 179.7°E which put it about 105 miles (17 km) south of Suva, Fiji. Ana was moving toward the south-southeast at 9 m.p.h. (15 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 978 mb.

At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Lucas was located at latitude 13.2°S and longitude 156.0°E which put it about 870 miles (1405 km) west-northwest of New Caledonia. Lucas was moving toward the east at 17 m.p.h. (28 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 979 mb. Tropical Cyclone Lucas is forecast to strengthen into the equivalent of a hurricane/typhoon. It could affect New Caledonia and Vanuatu in a few days.

Tropical Cyclone Wasi Brings Wind and Rain to Samoa

Tropical Cyclone Wasi brought wind and rain to Samoa  on Saturday.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Wasi was located at latitude 16.7°S and longitude 171.3°W which put it about 140 miles (225 km) south-southwest of Pago Pago, American Samoa.  Wasi was moving toward the south-southeast at 14 m.p.h. (22 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 996 mb.

The eastern side of Tropical Cyclone Wasi brought wind and rain to parts of Samoa on Saturday.  A weather station in Pago Pago, American Samoa reported a sustained wind speed of 25 m.p.h. (40 km/h) and a wind gust of 43 m.p.h. (69 km/h).  Several inches of rain also fell on parts of Samoa.

Tropical Cyclone Wasi moved under the western side of an upper level ridge over the South Pacific Ocean.  The ridge produce strong northerly winds which blew across the top of Wasi.  Those winds caused strong vertical wind shear and Tropical Cyclone Wasi began to weaken.  Many of the taller thunderstorms dissipated.  Some storms were still occurring in a band south and east of the center of circulation.  Bands in other parts 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 Wasi.

Tropical Cyclone Wasi will move through an environment unfavorable for intensification.  Wasi will move over water where the Sea Surface Temperature is near 28°C.  However, the upper level ridge will continue to cause strong vertical wind shear.  The shear will be strong enough to prevent significant intensification and Tropical Cyclone Wasi could continue to weaken since it has a small circulation.

Tropical Cyclone Wasi will move around the western end of a high pressure system over the South Pacific Ocean.  The high will steer Wasi toward the south.  On its anticipated track Tropical Cyclone Wasi could pass near Niue in about 18 hours.  Wasi will bring gustier winds and rain showers to Niue on Sunday.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vicky was dissipating south of Niue.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Vicky was located at latitude 22.6°S and longitude 168.6°W which put it about 250 miles (400 km) south-southeast of Niue.  Vicky was moving toward the south at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1004 mb.

Tropical Cyclone Wasi Develops Near Samoa

Tropical Cyclone Wasi developed near Samoa on Friday night.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Wasi was located at latitude 13.6°S and longitude 172.9°W which put it about 20 miles (35 km) west of Falealupo, Samoa and about 185 miles (300 km) west-northwest of Pago Pago, American Samoa.  Wasi was moving toward the southeast at 11 m.p.h. (17 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 993 mb.

Tropical Cyclone Wasi spun up out of the same elongated trough of low pressure near Samoa that produced Tropical Cyclone Vicky on Thursday.  A small center of low pressure developed west-northwest of Samoa on Friday.  More thunderstorms formed near the center of circulation and the system was classified as Tropical Cyclone Wasi.  Microwave satellite imagery indicated that there was a tight inner core in the tropical cyclone.  Storms near the core were generating upper level divergence which was pumping mass away from Tropical Cyclone Wasi.  The circulation around Wasi was even smaller than the circulation around Tropical Cyclone Vicky.  Winds to tropical storm force only extended out about 50 miles (80 km) from the center of Tropical Cyclone Wasi.

Tropical Cyclone Wasi will move into an environment somewhat favorable for intensification during the next 24 to 36 hours.  Wasi will move over water where the Sea Surface Temperature is near 28°C.  It will move under the western end of an upper level ridge over the South Pacific Ocean.  The ridge will produce northwesterly winds which will blow toward the top of the tropical cyclone.  Those winds will cause moderate vertical wind shear, but the winds may not be strong enough to prevent intensification.  Tropical Cyclone Wasi could strengthen during the next 24 to 36 hours.  Since the circulation around Wasi is so small, if the tropical cyclone moves into an area where the upper level winds are stronger, it could weaken quickly.

Tropical Cyclone Wasi will move around the western end of a high pressure system over the South Pacific Ocean.  The high will steer Wasi toward the southeast during the next 12 hours.  Wasi will move more toward the south later in the weekend.  On its anticipated track Tropical Cyclone Wasi will bring gust winds and locally heavy rain to portions of Samoa during the next 24 hours.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vicky weakened as it passed near Niue on Friday.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Vicky was located at latitude 19.7°S and longitude 168.7°W which put oit about 95 miles (150 km) southeast of Niue.  Vicky was moving toward the south-southeast at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1001 mb.