Tag Archives: Cocos Islands

Tropical Cyclone Bakung Weakens

Tropical Cyclone Bakung weakened as it moved over the South Indian Ocean west-northwest of the Cocos Islands on Monday.  At 4:00 p.m. EST on Monday the center of Tropical Cyclone Bakung was located at latitude 10.9°S and longitude 92.9°E which put the center about 300 miles (485 km) west-northwest of the Cocos Islands.  Bakung was moving toward the east 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 997 mb.

Stronger vertical wind shear caused Tropical Cyclone Bakung to weaken on Monday.  There were still thunderstorms around the center of Bakung’s circulation.  However, the vertical wind shear inhibited the upper level divergence.  Storms near the center of Bakung pumped less mass away from the tropical cyclone.  The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased on Monday.

The circulation around Tropical Cyclone Bakung was very small.  Winds to tropical storm force extended out 65 miles (105 km) from the center of Bakung’s circulation.

Tropical Cyclone Bakung will move through an environment that will continue to be unfavorable for intensification during the next 24 hours.  Bakung will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the southwestern part of an upper level ridge that is centered east of the Cocos Islands.  The upper level ridge will produce northwesterly winds that will blow toward the top of Bakung’s circulation.  Those winds will continue to cause the moderate vertical wind shear.  The moderate vertical wind shear will cause Tropical Cyclone Bakung to continue to weaken during the next 24 hours.

The northwesterly winds blowing toward the top of Tropical Cyclone Bakung will continue to steer Bakung toward the east during the next 24 hours.  On its anticipated track, Tropical Cyclone Bakung will move closer to the Cocos Islands.

Tropical Cyclone Bakung Stalls

Tropical Cyclone Bakung stalled over the South Indian Ocean west-northwest of the Cocos Islands on Sunday.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Bakung was located at latitude 10.9°S and longitude 91.0°E which put the center about 415 miles (670 km) west-northwest of the Cocos Islands.  Bakung was moving toward the south at 4 m.p.h. (6 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 981 mb.

Tropical Cyclone Bakung weakened a little after it stalled over the South Indian Ocean on Sunday.  An eye was no longer visible at the center of Bakung’s circulation.  Thunderstorms were still occurring near the center of Tropical Cyclone Bakung.  Storms near the center of Bakung generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass in the upper levels was a little less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure was increasing slowly.

The circulation around Tropical Cyclone Bakung continued to be very small.  Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of Bakung’s circulation.  Winds to tropical storm force extended out 50 miles (80 km) from the center of Tropical Cyclone Bakung.

Tropical Cyclone Bakung will move through an environment that will be unfavorable for intensification during the next 24 hours.  Bakung will move under the southwestern part of an upper level ridge that is centered east of the Cocos Islands.  The upper level ridge will produce northwesterly winds that will blow toward the top of Bakung’s circulation.  Those winds will cause the moderate vertical wind shear.  The moderate vertical wind shear will cause Tropical Cyclone Bakung to weaken during the next 24 hours.  Because the circulation around Bakung is so small, it could weaken rapidly at times.

The northwesterly winds blowing toward the top of Tropical Cyclone Bakung will start to steer Bakung back toward the east during the next 24 hours.  On its anticipated track, Tropical Cyclone Bakung will move closer to the Cocos Islands.

Tropical Cyclone Bakung Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Bakung intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean on Saturday.  At 7:00 p.m. EST on Saturday the center of Tropical Cyclone Bakung was located at latitude 10.2°S and longitude 91.4°E which put the center about 390 miles (630 km) west-northwest of the Cocos Islands.  Bakung was moving toward the west-southwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (165 km/h).  The minimum surface pressure was 971 mb.

Tropical Cyclone Bakung intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean west-northwest of the Cocos Islands on Saturday.  A very small circular eye developed at the center of Bakung’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Bakung.  Storms near the center of Bakung generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Bakung was very small.  Winds to hurricane/typhoon force extended out 10 miles (15 km) from the center of Bakung’s circulation.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Cyclone Bakung.

Tropical Cyclone Bakung will move into an environment that will become unfavorable for intensification during the next 24 hours.  Bakung will move under the southwestern part of an upper level ridge that is centered east of the Cocos Islands.  The upper level ridge will produce northwesterly winds that will blow toward the top of Bakung’s circulation.  Those winds will cause the vertical wind shear to increase.  Tropical Cyclone Bakung will start to weaken when the vertical wind shear increases.  Because the circulation around Bakung is so small, it could weaken rapidly when the vertical wind shear increases.

The northwesterly winds blowing toward the top of Tropical Cyclone Bakung will start to steer Bakung back toward the east on Sunday.  On its anticipated track, Tropical Cyclone Bakung will move back closer to the Cocos Islands.

Tropical Cyclone Bakung Forms North of Cocos Islands

Tropical Cyclone Bakung formed over the South Indian Ocean north of the Cocos Islands on Friday.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Bakung was located at latitude 8.7°S and longitude 94.9°E which put the center about 270 miles (435 km) north-northwest of the Cocos Islands.  Bakung was moving toward the west at 14 m.p.h. (22 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 999 mb.

A low pressure system over the South Indian Ocean strengthened on Friday and the system was designated as Tropical Cyclone Bakung.

More thunderstorms formed near the center of Tropical Cyclone Bakung on Friday.  More thunderstorms also developed in bands revolving around the center of Bakung’s circulation.  Storms near the center of Bakung started to generate upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Bakung was small.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Bakung’s circulation.

Tropical Cyclone Bakung will move through an environment favorable for intensification during the next 24 hours.  Bakung will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the western part of an upper level ridge over northern Australia.  The upper level ridge will produce northerly winds that will blow toward the top of Bakung’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Cyclone Bakung will intensify during the next 24 hours.

Tropical Cyclone Bakung will move around the northwestern part of a high pressure system tat is over Australia.  The high pressure will steer Bakung toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Bakung will move farther away from the Cocos Islands during the weekend.

Courtney Begins Transition to Extratropical Cyclone

Tropical Cyclone Courtney began a transition to an extratropical cyclone over the South Indian ocean on Monday.  At 5:00 p.m. EDT on Monday the center of Tropical Cyclone Courtney was located at latitude 25.0°S and longitude 88.7°E which put the center about 1020 miles (1645 km) south-southwest of the Cocos Islands.  Courtney was moving toward the south at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 986 mb.

Tropical Cyclone Courtney began a transition to an extratropical cyclone over the South Indian Ocean south-southwest of the Cocos Islands on Monday.  An upper level trough was producing strong northwesterly winds that were blowing across the top of Courtney’s circulation.  Those winds were causing strong vertical wind shear.  The strong wind shear blew off the tops of many of the thunderstorms in Tropical Cyclone Courtney.  A few thunderstorms were still occurring in a bands in the southeastern periphery of Courtney’s circulation.  Bands in the other parts of Tropical Cyclone Courtney consisted primarily of showers and lower clouds.

The lack of thunderstorms in much of Tropical Cyclone Courtney caused the distribution of winds speeds to become asymmetrical.  Winds to tropical storm force extended out 165 miles (265 km) in the southern half of Courtney’s circulation.  Winds to tropical storm force only extended out 85 miles (135 km) in the northern half of Tropical Cyclone Courtney.

Tropical Cyclone Courtney will move through an environment that will be unfavorable for intensification of a tropical cyclone during the next 24 hours.  Courtney will move over water where where the Sea Surface Temperatures are near 24°C.  It will move under the eastern side of an upper level trough over the South Indian Ocean.  The upper level trough will produce  strong northwesterly winds that will blow toward the top of Courtney’s circulation.  Those winds will cause strong vertical wind shear to continue.  The combination of colder Sea Surface Temperatures and strong vertical wind shear will cause Tropical Cyclone Courtney to continue to make a transition to an extratropical cyclone during the next 24 hours.

Since much of the circulation of Tropical Cyclone Courtney only exists in the the lower levels of the atmosphere, Courtney will be steered by the winds at those levels.  Courtney will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Courtney toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Courtney will move farther away from the Cocos Islands.

Tropical Cyclone Courtney Weakens

Tropical Cyclone Courtney weakened over the South Indian Ocean southwest of the Cocos Islands on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Cyclone Courtney was located at latitude 23.0°S and longitude 88.0°E which put the center about 935 miles (1505 km) southwest of the Cocos Islands.  Courtney was moving toward the south at 9 m.p.h. (15 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 980 mb.

Tropical Cyclone Courtney weakened over the South Indian Ocean southwest of the Cocos Islands on Sunday.  An upper level trough over the South Indian Ocean produced northwesterly winds that blew toward the top of Courtney’s circulation.  Those winds caused moderate vertical wind shear.  The vertical wind shear caused the distribution of thunderstorms in Tropical Cyclone Courtney to become asymmetrical.  Thunderstorms were occurring in bands in the eastern and southern parts of Courtney’s circulation.  Bands in the western and northern parts of Tropical Cyclone Courtney consisted primarily of showers and lower clouds.

The size of the circulation around Tropical Cyclone Courtney increased on Sunday.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Courtney’s circulation.  Winds to tropical storm force extended out 135 miles (220 km) from the center of Tropical Cyclone Courtney.

Tropical Cyclone Courtney will move through an environment that will be unfavorable for intensification during the next 24 hours.  Courtney will move over water where where the Sea Surface Temperatures are near 24°C.  It will move under the eastern side of an upper level trough over the South Indian Ocean.  The upper level trough will produce northwesterly winds that will blow toward the top of Courtney’s circulation. Those winds will cause moderate vertical wind shear to continue.  The combination of colder Sea Surface Temperatures and moderate vertical wind shear will cause Tropical Cyclone Courtney to continue to weaken during the next 24 hours.

Tropical Cyclone Courtney will move around the western end of a high pressure system over the South Indian Ocean.  The high pressure system will steer Courtney toward the south during the next 24 hours.  On its anticipated track, Tropical Cyclone Courtney will move farther away from the Cocos Islands.

Tropical Cyclone Courtney Equivalent of Cat. 4 Hurricane

Tropical Cyclone Courtney was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale over the South Indian Ocean on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Courtney was located at latitude 19.9°S and longitude 89.1°E which put the center about 715 miles (1150 km) southwest of the Cocos Islands.  Courtney was moving toward the southwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 145 m.p.h. (230 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 939 mb.

Tropical Cyclone Courtney strengthened on Saturday.  Courtney was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.  A small circular eye was present at the center of Courtney’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Courtney’s circulation.  Storms near the center generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Courtney was small.  Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Courtney’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Courtney.

The Hurricane Intensity Index (HII) for Tropical Cyclone Courtney was 29.9.  The Hurricane Size Index (HSI) was 10.7 and the Hurricane Wind Intensity Size Index (HWISI) was 40.6.

Tropical Cyclone Courtney will move through an environment that will become unfavorable for intensification during the next 24 hours.  Courtney will move over water where where the Sea Surface Temperatures are near 26°C.  It will move under the eastern side of an upper level trough over the South Indian Ocean.  The upper level trough will produce northwesterly winds that will blow toward the top of Courtney’s circulation.  Those winds will cause the vertical wind shear to increase.  Tropical Cyclone Courtney will weaken when the vertical wind shear increases.

Tropical Cyclone Courtney will move around the western end of a high pressure system over the South Indian Ocean.  The high pressure system will steer Courtney toward the south during the next 24 hours.  On its anticipated track, Tropical Cyclone Courtney will move farther away from the Cocos Islands.

Tropical Cyclone Dianne Brings Wind and Rain to Western Australia

Tropical Cyclone Dianne brought wind and rain to Western Australia on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Dianne was located at latitude 16.6°S and longitude 123.8°E which put the center about 75 miles (120 km) north-northeast of the Derby, Australia.  Dianne was moving toward the south 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 991 mb.

A Warning is in effect for the portion of the coast between Kuri Bay and Derby.

The center of Tropical Cyclone Dianne made landfall on the coast of Western Australia north-northeast of Derby.  Dianne was the equivalent of a tropical storm at the time of landfall.  The circulation around Tropical Cyclone Dianne was small.  Winds to tropical storm force only extended out 65 miles (105 km) from the center of Dianne’s circulation.

Tropical Cyclone Dianne will move around the western end of a high pressure system over northern Australia.  The high pressure system will steer Dianne toward the south during the next 24 hours.  On its anticipated track, Tropical Cyclone Dianne will move inland over Western Australia during the next 24 hours.

Tropical Cyclone Dianne will bring strong winds and locally heavy rain to parts of Western Australia.  Heavy rain could cause flash floods in some locations.

Flood Watches are in effect for the Tanami Desert, the Western Desert and the Sandy Desert.

Elsewhere over the South Indian Ocean, Tropical Cyclone Courtney intensified to the equivalent of a major hurricane southwest of the Cocos Islands.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Courtney was located at latitude 17.6°S and longitude 92.5°E which put the center about 445 miles (715 km) southwest of the Cocos Islands.  Courtney was moving toward the west-southwest at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 948 mb.

Tropical Cyclone Dianne Nears Western Australia

Tropical Cyclone Dianne neared the coast of Western Australia on Friday morning.  At 5:00 a.m. EDT on Friday the center of Tropical Cyclone Dianne was located at latitude 15.3°S and longitude 123.6°E which put the center about 140 miles (225 km) north of the Derby, Australia.  Dianne was moving toward the south-southeast 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 991 mb.

A Warning is in effect for the area between Kuri Bay and Derby.

A Tropical Low strengthened to Tropical Cyclone Dianne near the coast of Western Australia during Thursday night.  More thunderstorms formed near the center of Tropical Cyclone Dianne.  More thunderstorms also formed in bands revolving around the center of Dianne’s circulation.  Storms near the center of Dianne generated more upper level divergence that pumped mass away from the tropical cyclone.  The removal of more mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Dianne was small.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Dianne’s circulation.

Tropical Cyclone Dianne will move through an environment somewhat favorable for intensification during the next few hours.  Dianne will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the northern part of an upper level ridge that extends from over Australia to the South Indian Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of the Tropical Low.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification.  Dianne could intensify during the next few hours.

Tropical Cyclone Dianne will move around the western end of a high pressure system over northern Australia.  The high pressure system will steer Dianne toward the southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Dianne will make landfall on the coast of Western Australia northeast of Derby in a few hours.

Tropical Cyclone Dianne will bring strong winds and locally heavy rain to parts of Western Australia.  Heavy rain could cause flash floods in some locations.

Flood Watches are in effect for the Tanami Desert, the Western Desert and the Sandy Desert.

Elsewhere over the South Indian Ocean, Tropical Cyclone Courtney passed south of the Cocos Islands.  At 5:00 a.m. EDT on Friday the center of Tropical Cyclone Courtney was located at latitude 16.9°S and longitude 94.9°E which put the center about 330 miles (530 km) south-southwest of the Cocos Islands.  Courtney was moving toward the west at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 972 mb.

Tropical Low Prompts Watch for Western Australia

A risk posed by a Tropical Low prompted the Australian Bureau of Meteorology to issue a Watch for a portion of the coast of Western Australia on Thursday.  At 5:00 a.m. EDT on Thursday the center of the Tropical Low was located at latitude 13.8°S and longitude 121.8°E which put the center about 215 miles (350 km) west-northwest of the Kuri Bay, Australia.  The Tropical Low was moving toward the east-northeast at 5 m.p.h. (7 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 997 mb.

A Watch is in effect for the portion of the coast of Western Australia from Mitchell Plateau to Beagle Bay.  The Watch includes Derby and Beagle Bay.

A low pressure system over the South Indian Ocean west of Australia exhibited more organization on Thursday morning and the Australian Bureau of Meteorology classified the system as a Tropical Low.  The U.S. Joint Typhoon Warning Center designated the low pressure system as Invest 93S.

The distribution of thunderstorms in the Tropical Low was asymmetrical.  Thunderstorms were occurring in bands in the western side of the Tropical Low.  Bands in the eastern side of the Tropical Low consisted primarily of showers and lower clouds.  Storms near the center of circulation generated upper level divergence that pumped mass away to the west of the Tropical Low.  The removal of mass caused the surface pressure to decrease slowly.

The Tropical Low will move through an environment somewhat favorable for intensification during the next 24 hours.  The Tropical Low will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the northern part of an upper level ridge that extends from over Australia to the South Indian Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of the Tropical Low.  Those winds will cause moderate vertical wind shear.  The moderate vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification.  The Tropical Low could intensify during the next 24 hours.

The Tropical Low will move around the western end of a high pressure system over northern Australia.  The high pressure system will steer the Tropical Low toward the southeast during the next 24 hours.  On its anticipated track, the Tropical Low will make landfall on the coast of Western Australia between Kuri Bay and Derby in 36 hours.

The Tropical Low will bring strong winds and locally heavy rain to parts of Western Australia.  Heavy rain could cause flash floods in some locations.

Elsewhere over the South Indian Ocean, Tropical Cyclone Courtney continued to strengthen south-southeast of the Cocos Islands.  At 5:00 a.m. EDT on Thursday the center of Tropical Cyclone Courtney was located at latitude 16.8°S and longitude 99.5°E which put the center about 380 miles (610 km) south-southeast of the Cocos Islands.  Courtney was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 973 mb.