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Tropical Cyclone Jenna Weakens

Tropical Cyclone Jenna weakened on Wednesday as it moved over the South Indian Ocean southwest of the Cocos Islands.  At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Jenna was located at latitude 18.6°S and longitude 90.9°E which put the center about 580 miles (940 km) southwest of the Cocos Islands.  Jenna was moving toward the west-southwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 993 mb.

Tropical Cyclone Jenna weakened steadily on Wednesday as it moved southwest of the Cocos Islands.  The southwestern part of an upper level ridge produced strong northwesterly winds that blew toward the top of Jenna’s circulation.  Those winds caused strong vertical wind shear.  The strong upper level winds also blew the tops off of many of the thunderstorms that were part of Tropical Cyclone Jenna.

There were few thunderstorms left in Tropical Cyclone Jenna because of the strong vertical wind shear.  The bands revolving around the center of Jenna’s circulation consisted primarily of showers and lower clouds.  There was little upper level divergence.  Mass was still converging in the lower levels of the atmosphere.  So, the convergence of mass caused the surface pressure to increase.

The strong vertical wind shear also caused the distribution of wind speeds in Tropical Cyclone Jenna to become more asymmetrical.  Winds to tropical storm force extended out 100 miles (160 km) in the southern side of Jenna’s circulation.  Tropical storm force winds extended out 35 miles (55 km) in the northern side of Tropical Cyclone Jenna.

Tropical Cyclone Jenna will move through an environment very unfavorable for intensification during the next 24 hours.  Jenna will move over water where the Sea Surface Temperatures are near 26°C.  It will continue to move under the southwestern part of an upper level ridge that is over the South Indian Ocean.  The upper level ridge will continue to produce strong northwesterly winds that will blow toward the top of Jenna’s circulation.  Those winds will continue to cause strong vertical wind shear.  Tropical Cyclone Jenna will continue to weaken because of the strong vertical wind shear.

Tropical Cyclone Jenna will move around the northern side of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Jenna toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Jenna will continue to move farther away from the Cocos Islands.

Tropical Cyclone Jenna Moves Away From the Cocos Islands

Tropical Cyclone Jenna moved farther away from the Cocos Islands on Tuesday.  At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone Jenna was located at latitude 16.9°S and longitude 93.9°E which put the center about 380 miles (615 km) southwest of the Cocos, Islands.  Jenna was moving toward the southwest at 8 m.p.h. (13 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 976 mb.

Tropical Cyclone Jenna strengthened as it moved away from the Cocos Islands on Tuesday.  A small eye was visible at the center of Jenna’s circulation earlier on Tuesday.  The eye was no longer visible in the most recent satellite images.  A ring of thunderstorms surrounded the eye earlier today and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms revolved around the core of Tropical Cyclone Jenna.  Storms near the core of Jenna generated upper level divergence that pumped mass away from the tropical cyclone.

The size of the circulation around Tropical Cyclone Jenna increased on Tuesday.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Jenna’s circulation.  Winds to tropical storm force extended out 160 miles (260 km) in the eastern side of Tropical Cyclone Jenna.  Winds to tropical storm force extended out 100 miles (160 km) in the western side of Jenna’s circulation.

Tropical Cyclone Jenna will move through an environment unfavorable for intensification during the next 24 hours.  Jenna will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southwestern part of an upper level ridge that is over the South Indian Ocean.  The upper level ridge will produce northwesterly winds that will blow toward the top of Jenna’s circulation.  Those winds will cause the vertical wind shear to increase. Tropical Cyclone Jenna will weaken when the vertical wind shear increases.

Tropical Cyclone Jenna will move around the western side of a high pressure system that is over the eastern part of the South Indian Ocean.  The high pressure system will steer Jenna toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Jenna will continue to move farther away from the Cocos Islands.

Tropical Cyclone Jenna Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Jenna rapidly intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean on Monday.  At 4:00 p.m. EST on Monday the center of Tropical Cyclone Jenna was located at latitude 14.8°S and longitude 95.8°E which put the center about 160 miles (260 km) south-southwest of the Cocos, Islands.  Jenna was moving toward the south-southwest at 14 m.p.h. (22 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 987 mb.

The Australian Bureau of Meteorology cancelled the Warning for the Cocos Islands when Tropical Cyclone Jenna moved away from the islands.

Tropical Cyclone Jenna rapidly intensified to the equivalent of a hurricane/typhoon on Monday.  The inner end of a rainband wrapped around the center of Jenna’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Jenna.  Storms near the center of Jenna generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease rapidly.

The circulation around Tropical Cyclone Jenna was small.  The strongest winds were occurring in the northwestern quadrant of Jenna’s circulation.  Winds to hurricane/typhoon force extended out 25 miles (40 km) in the northwestern quadrant of Tropical Cyclone Jenna.  Winds to tropical storm force extended out 65 miles (105 km) from the center of Jenna’s circulation.

Tropical Cyclone Jenna will move through an environment favorable for intensification during the next 24 hours.  Jenna will move over water where the Sea Surface Temperatures are near 28°C.  It will move through a region where the upper level winds are weak and the will be little vertical wind shear.  Tropical Cyclone Jenna will intensify during the next 24 hours.

Tropical Cyclone Jenna will move around the western side of a high pressure system that is over the eastern part of the South Indian Ocean.  The high pressure system will steer Jenna toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Jenna will continue to move farther away from the Cocos Islands.

Tropical Cyclone Jenna Develops Near Cocos Islands

Tropical Cyclone Jenna developed over the South Indian Ocean near the Cocos Islands on Sunday night.  At 4:00 a.m. EST on Monday the center of Tropical Cyclone Jenna was located at latitude 12.7°S and longitude 96.9°E which put the center about 15 miles (25 km) east of the Cocos, Islands.  Jenna was moving toward the south-southwest 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 1000 mb.

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

A low pressure system over the South Indian Ocean near the Cocos Islands strengthened on Sunday night and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Jenna.

The circulation around Tropical Cyclone Jenna exhibited more organization early on Monday.  The inner end of a rainband wrapped around the western side of the center of Jenna’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Jenna.  Storms near the center of Jenna generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds in Tropical Cyclone Jenna was relatively symmetrical.  Winds to tropical storm force extended out 145 miles (235 km) from the center of Jenna’s circulation.

Tropical Cyclone Jenna will move through an environment favorable for intensification during the next 24 hours.  Jenna will move over water where the Sea Surface Temperatures are near 28°C.  It will move through a region where the upper level winds are weak and the will be little vertical wind shear.  Tropical Cyclone Jenna will intensify during the next 24 hours.

Tropical Cyclone Jenna will move around the western side of a high pressure system that is over the eastern part of the South Indian Ocean.  The high pressure system will steer Jenna toward the south-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Jenna will move away from the Cocos Islands later today.

Tropical Cyclone Jenna will bring strong winds and heavy rain to the Cocos Islands during the next few hours.  Heavy rain could cause flash floods in some locations.

Elsewhere over the South Indian Ocean, Tropical Cyclone Grant was passing north of La Reunion.  At 7:00 a.m.EST Monday the center of Tropical Cyclone Grant was located at latitude 16.2°S and longitude 56.0°E which put the center about 325 miles (525 km) north of La Reunion,   Grant was moving toward the west at 11 m.p.h. (17 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 1006 mb.

Tropical Cyclone Elvis Spins Near Southwest Madagascar

Tropical Cyclone Elvis continued to spin near southwestern Madagascar on Wednesday.  At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Elvis was located at latitude 26.0°S and longitude 43.3°E which put the center about 115 miles (185 km) southwest of Beloha, Madagascar.  Elvis was moving toward the south-southeast at 13 m.p.h. (21 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 989 mb.

Although Tropical Cyclone Elvis strengthened on Wednesday, drier air appeared to be getting pulled into Elvis’ circulation.  Many of the thunderstorms near the center of Tropical Cyclone Elvis dissipated. Thunderstorms were still occurring in bands in the southeastern part of Elvis’ circulation.  Bands in the other parts of Tropical Cyclone Elvis consisted primarily of showers and lower clouds.  The few remaining thunderstorms near the center of Elvis were not generating much upper level divergence

The distribution of wind speeds in Tropical Cyclone Elvis was asymmetrical.  Winds to tropical storm force extended out 140 miles (220 km) in the southeastern part of Elvis’s circulation.  Winds to tropical storm force only extended out 50 miles in the northern side of Tropical Cyclone Elvis.

Tropical Cyclone Elvis will move through an environment marginally favorable for intensification during the next 24 hours.  Elvis will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the eastern side of an upper level trough near southern Africa.  The upper level trough will produce northwesterly winds that will blow toward the top of Elvis’ circulation.  Those winds will cause moderate to strong vertical wind shear. The vertical wind shear will inhibit intensification of Tropical Cyclone Elvis.  Drier air will also inhibit the intensification of Elvis.  The vertical wind shear and the drier air are likely to cause Tropical Cyclone Elvis to weaken during the next 24 hours.

The upper level trough near southern Africa will steer Tropical Cyclone Elvis toward the southeast during the next 24 hours.  On its anticipated track, the center of Tropical of Cyclone Elvis will pass south of southern Madagascar.  Elvis will move away from Madagascar on Friday.

Tropical Cyclone Gabrielle Transitions to an Extratropical Cyclone

Former Tropical Cyclone Gabrielle made a transition to an extratropical cyclone northwest of New Zealand on Friday. At 4:00 p.m. EST on Friday the center of former Tropical Cyclone Gabrielle was located at latitude 27.2°S and longitude 165.3°E which put it about 670 miles (1080 km) northwest of Auckland, New Zealand. Gabrielle was moving toward the southeast at 29 m.p.h. (46 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.

Former Tropical Cyclone Gabrielle made a transition to an extratropical cyclone on Friday. Gabrielle moved over water where the Sea Surface Temperatures are near 24˚C. An upper level trough east of Australia produced northwesterly winds that blew toward the top of Gabrielle’s circulation. Those winds cause strong vertical wind shear. A combination of cooler water and strong vertical wind shear caused former Tropical Cyclone Gabrielle to make a transition to a strong extratropical cyclone. Strong thunderstorms were still occurring in bands in the southern half of the extratropical cyclone. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. The transition to an extratropical cyclone caused the size of the low pressure system to expand. Winds to tropical storm force extended out 330 miles (530 km) from the center of circulation.

The upper level trough east of Australia will steer the extratropical cyclone quickly toward the southeast. On its anticipated track, former Tropical Cyclone Gabrielle could affect northern New Zealand during the weekend. The extratropical cyclone will bring strong winds and locally heavy rain to northern New Zealand. Heavy rain could cause flash floods in some locations.

Tropical Cyclone Gabrielle Intensifies to Equivalent of a Hurricane/Typhoon

Tropical Cyclone Gabrielle intensified to the equivalent of a hurricane/typhoon over the Coral Sea on Thursday morning. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Gabrielle was located at latitude 20.1°S and longitude 155.6°E which put it about 565 miles (910 km) north-northeast of Brisbane, Australia. Gabrielle was moving toward the southeast at 13 m.p.h. (20 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 971 mb.

Tropical Cyclone Gabrielle intensified over the Coral Sea on Thursday morning. The inner end of a rainband wrapped around the center of Gabrielle’s circulation. A small eye appeared to be forming at the center of circulation. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Gabrielle. Storms near the core generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Gabrielle’s circulation. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation.

Tropical Cyclone Gabrielle will move through an environment favorable for intensification during the next 24 hours. Gabrielle will move over over water where the Sea Surface Temperatures are near 27˚C. An upper level trough near the east coast of Australia will produce northwesterly winds that will blow toward the top of Gabrielle’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Tropical Cyclone Gabrielle is likely to intensify during the next 24 hours.

The upper level trough near the east coast of Australia will steer Tropical Cyclone Gabrielle toward the southeast during the next 48 hours. On its anticipated track Gabrielle will move between Australia and New Caledonia. Bands in the eastern side of Tropical Cyclone Gabrielle could bring gusty winds and locally heavy rain to New Caledonia. Gabrielle will move over cooler water during the weekend and the vertical wind shear will increase. Cooler water and more wind shear will cause Tropical Cyclone Gabrielle to make a transition to an extratropical cyclone. Gabrielle could affect northern New Zealand as a strong extratropical cyclone in a few days.

Tropical Cyclone Freddy Moves Away from Western Australia

Tropical Cyclone Freddy moved away from Western Australia on Wednesday morning. At 10:00 a.m. EST on Wednesday the center of Tropical Cyclone Freddy was located at latitude 16.1°S and longitude 112.7°E which put it about 440 miles (710 km) north of Learmonth, Australia. Freddy was moving toward the west-southwest at 9 m.p.h. (15 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 Cyclone Freddy started to weaken as it moved away from Western Australia on Wednesday morning. Freddy was moving under the northwestern part of an upper level ridge over Australia. The upper level ridge was producing easterly winds that were blowing toward the top of Freddy’s circulation. Those winds were causing moderate vertical wind shear. The wind shear caused the distribution of thunderstorms in Tropical Cyclone Freddy to become asymmetrical. Many of the thunderstorms were occurring in bands in the western half of Freddy’s circulation. Bands in the eastern side of Freddy consisted primarily of showers and lower clouds. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Tropical Cyclone Freddy. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

Tropical Cyclone Freddy will move through an environment that is unfavorable for intensification during the next 24 hours. Freddy will move over over water where the Sea Surface Temperatures are near 28˚C. However, the upper level ridge over Australia will continue to cause moderate vertical wind shear. The wind shear is likely to cause Tropical Cyclone Freddy to weaken during the next 24 hours. The wind shear could lessen when Freddy moves farther west on Friday. If the shear lessens, then Tropical Cyclone Freddy could start to intensify again.

Elsewhere, Tropical Cyclone Gabrielle strengthened over the Coral Sea. At 10:00 a.m. EST on Wednesday the center of Tropical Cyclone Gabrielle was located at latitude 17.2°S and longitude 152.8°E which put it about 450 miles (725 km) east of Cairns, Australia. Gabrielle was moving toward the south-southwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 983 mb. Tropical Cyclone Gabrielle is forecast to move toward the southeast and to strengthen to the equivalent of a hurricane/typhoon.

Tropical Cyclone Gabrielle Forms over the Coral Sea

Tropical Cyclone Gabrielle formed over the Coral Sea on Tuesday night. At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Gabrielle was located at latitude 15.7°S and longitude 153.3°E which put it about 230 miles (370 km) east-northeast of Willis Island. Gabrielle was moving toward the south-southwest at 10 m.p.h. (16 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 995 mb.

A low pressure system over the Coral Sea strengthened on Tuesday night and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Gabrielle. The inner end of a rainband wrapped around the northern and eastern side of the center of Gabrielle’s circulation. Other bands of showers and thunderstorms were revolving 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 65 miles (105 km) from the center of Tropical Cyclone Gabrielle.

Tropical Cyclone Gabrielle will move through an environment favorable for intensification during the next 24 hours. Gabrielle will move over over water where the Sea Surface Temperatures are near 29˚C. It will move under the center of an upper level ridge over the Coral Sea. The upper level winds are weak near the center of the ridge and there will be little vertical wind shear. Tropical Cyclone Gabrielle will intensify during the next 24 hours. Gabrielle could intensify rapidly at times and it could strengthen to the equivalent of a hurricane/typhoon.

Tropical Cyclone Gabrielle will move around the western end of a high pressure system over the Southwest Pacific Ocean during the next 24 hours. The high pressure system will steer Gabrielle toward the south. On its anticipated track Tropical Cyclone Gabrielle will remain east of Australia. An upper level trough over Australia will steer Gabrielle toward the southeast later this week.

Tropical Cyclone Dumako Hits Northern Madagascar

Tropical Cyclone Dumako hit northern Madagascar on Tuesday morning. At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Dumako was located at latitude 16.8°S and longitude 49.9°E which put it about 25 miles (40 km) northeast of Ivongo, Madagascar. Dumako was moving toward the west 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 992 mb.

Tropical Cyclone Dumako hit the coast of northern Madagascar between Mananara and Ivongo on Tuesday morning. Dumako was the equivalent of a tropical storm when it hit Madagascar. The maximum sustained wind speed was 50 m.p.h. (80 km/h). Winds to tropical storm force extended out 75 miles (120 km) from the center of Tropical Cyclone Dumako.

Tropical Cyclone Dumako will bring gusty winds and locally heavy rain to northern Madagascar during the next 24 hours. Locally heavy rain could cause flash floods in some locations, especially in mountainous regions. Dumako will move west across northern Madagascar during the next 36 hours. Tropical Cyclone Dumako will weaken steadily as it moves over the mountains in Madagascar.