Tag Archives: Cocos Islands

Tropical Cyclone Darian Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Darian rapidly intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean west of Cocos Islands on Monday. At 10:00 a.m. EST on Monday the center of Tropical Cyclone Darian was located at latitude 12.8°S and longitude 93.5°E which put it about 230 miles (370 km) west of Cocos Islands. Darian was moving toward the south-southeast at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 971 mb.

Tropical Cyclone Darian rapidly intensified to the equivalent of a hurricane/typhoon during the past 24 hours. The inner end of a rainband wrapped around the center of Darian’s circulation. An elliptical eye formed at the center of Tropical Cyclone Darian. 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 core of Darian’s circulation. Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone in all directions. Winds to hurricane/typhoon force extended out 40 miles (65 km/h) from the center of Tropical Cyclone Darian. Winds to tropical storm force extended out 125 miles (200 km) from the center.

Tropical Cyclone Darian will move through an environment favorable for intensification during the next 24 hours. Darian will move over water where the Sea Surface Temperatures are near 27˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Cyclone Darian is likely to intensify during the next 24 hours.

Tropical Cyclone Darian will move around the southwestern part of a high pressure system centered north of Australia. The high pressure system will steer Darian slowly toward the south during the next 24 hours. On its anticipated track Tropical Cyclone Darian will remain southwest of Cocos Islands. A subtropical high pressure system over the South Indian Ocean will steer Darian toward the west later this week.

Tropical Cyclone Darian Forms West of Cocos Islands

Tropical Cyclone Darian formed over the South Indian Ocean west of Cocos Islands on Sunday. At 7:00 a.m. EST on Sunday the center of Tropical Cyclone Darian was located at latitude 11.9°S and longitude 92.8°E which put it about 270 miles (440 km) west of Cocos Islands. Darian was moving toward the southwest at 3 m.p.h. (5 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 993 mb.

The circulation around a low pressure system over the South Indian Ocean west of Cocos Islands strengthened on Sunday and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Darian. The inner end of a rainband wrapped around the southern and western sides of the center of Darian’s circulation. Other bands of showers and thunderstorms were revolving around around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 100 miles (160 km) from the center of Darian.

Tropical Cyclone Darian will move through an environment favorable for intensification during the next 36 hours. Darian will move over water where the Sea Surface Temperatures are near 27˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Cyclone Darian will intensify during the next 36 hours. Darian could strengthen to the equivalent of a hurricane/typhoon.

Tropical Cyclone Darian will move around the southwestern part of a high pressure system centered north of Australia. The high pressure system will steer Darian slowly toward the southeast during the next 36 hours. On its anticipated track Tropical Cyclone Darian will pass southwest of Cocos Islands.

Tropical Cyclone Mangga Develops Northwest of Cocos Islands

Tropical Cyclone Mangga developed over the South Indian Ocean northwest of the Cocos Islands on Thursday.  At 11:00 a.m. EDT on Thursday the center of Tropical Cyclone Mangaa was located at latitude 9.4°S and longitude 93.1°E which put it about 320 miles (515 km) northwest of Cocos Island.  Mangga was moving toward the south-southeast at 7 m.p.h. (12 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.

The Australian Bureau of Meteorology issued a Warning for the Cocos Islands.

Tropical Cyclone Mangga developed within a trough of low pressure that extended from southwest of Indonesia to western Australia.  The trough had persisted for several days and a center of low pressure gradually formed northwest of the Cocos Islands during the past 24 hours.  The Australian Bureau of Meteorology designated the system as Tropical Cyclone Mangga on Thursday.

The circulation around Tropical Cyclone Mangga was still in the process of organizing.  The strongest thunderstorms were in a band on the western side of the circulation.  Bands on the eastern side of the circulation consisted primarily of showers and lower clouds.  More thunderstorms began to develop near the center of circulation on Thursday.  Storms developing near the center started to generate upper level divergence which was pumping mass away to the west of the tropical cyclone.  Winds to tropical storm force extended out 150 miles (240 km) from the center of Mangga.

Tropical Cyclone Mangga will move through an environment somewhat favorable for intensification during the next 24 to 36 hours.  Mannga will move over water where the Sea Surface temperature is near 27°C.  It will move under the northwestern part of an upper level ridge centered over Indonesia.  The ridge will produce easterly winds which will blow toward the top of the circulation.  Those winds will produce moderate vertical wind shear.  The wind shear may be the reason why the bands on the eastern side of Tropical Cyclone Mangga are weaker.  The shear will also inhibit intensification, but it will probably not be strong enough to prevent Manga from strengthening during the next 24 hours.

Tropical Cyclone Mangga will move around the western end of a high pressure system centered north of Australia.  The high will steer Mangga toward the southeast during the next few days.  On its anticipated track Tropical Cyclone Mangga will pass near the Cocos Islands in about 24 hours.  Manga will bring gusty winds and locally heavy rain to those islands.

Tropical Cyclone Kate Intensfies Rapidly over Southeastern Indian Ocean

Favorable oceanic and atmospheric conditions allowed Tropical Cyclone Kate to intensify very rapidly on Friday.  The maximum sustained wind speed increased from 50 m.p.h. to 120 m.p.h. during a 24 hour period.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Kate was located at latitude 12.9°S and longitude 93.8°E which put it about 215 miles west-southwest of the Cocos Islands and about 2450 miles west of Darwin, Australia.  Kate was moving toward the southwest at 5 m.p.h., which was taking it away from the Cocos Islands.  The maximum sustained wind speed was 120 m.p.h. which made Kate the equivalent of a Category 3 hurricane on the Saffir-Simpson Scale and it was estimated that there were gusts to 150 m.p.h.

Although there were upper level winds blowing from the east, which created some wind shear over Kate, it was able to develop strong upper level outflow which produced rapid intensification.  Some satellite imagery shows that the wind shear is causing the strongest thunderstorms to be on the western side of the center of circulation.  Recent visible and infrared satellite imagery show evidence of an circular eye developing.  Some further intensification is possible during the next 24 hours as long as the upper level outflow is able to pump out sufficient mass.  Eventually, as Kate moves toward higher latitudes the wind shear will increase and the Sea Surface Temperatures will decrease.  The more hostile environment will weaken the tropical cyclone and the weakening could be almost as rapid as the intensification was.

Kate is expected to continue to be steered in a generally southwesterly direction in the short term by a subtropical ridge.  As it moves farther south, it will begin to be affected by westerly midlatitude flow and it will start to recurve more toward the south.  Kate passed over the Cocos Islands earlier this week as a tropical storm.  It is expected to dissipate over the Indian Ocean and not affect any other land areas as a tropical cyclone.