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Tropical Cyclone Freddy Rapidly Intensifies to Equivalent of a Major Hurricane

Tropical Cyclone Freddy rapidly intensified to the equivalent of a major hurricane over the South Indian Ocean east-southeast of Cocos Islands on Saturday morning. At 10:00 a.m. EST on Saturday the center of Tropical Cyclone Freddy was located at latitude 14.9°S and longitude 102.5°E which put it about 450 miles (720 km) east-southeast of Cocos Islands. Freddy was moving toward the west at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 949 mb.

Tropical Cyclone Freddy rapidly intensified to the equivalent of a major hurricane on Saturday morning. A small circular eye with a diameter of 12 miles (19 km) formed at the center of Freddy’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds occurred in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Freddy. Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone.

The circulation around Tropical Cyclone Freddy was small. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Freddy. Winds to tropical storm force extended out 120 miles (195 km) from the center of circulation. The Hurricane Intensity Index (HII) for Tropical Cyclone Freddy was 22.1. The Hurricane Size Index (HSI) was 11.4 and the Hurricane Wind Intensity Size Index (HWISI) was 33.5.

Tropical Cyclone Freddy will move through an environment favorable for intensification during the next 24 hours. Freddy will move over over water where the Sea Surface Temperatures are near 28˚C. It will move under the northern side of an upper level ridge over the Southeast Indian Ocean. The upper level ridge will produce easterly winds that will blow toward the top of Freddy’s circulation. The winds in the lower levels of the atmosphere will also blow from the east. So, there will be little vertical wind shear. Tropical Cyclone Freddy could continue to intensify rapidly during the next few hours. Since the circulation around Freddy is small, the inner end of a rainband could wrap around the existing eye and eyewall. If concentric eyewalls form, then an eyewall replacement cycle could cause Tropical Cyclone to weaken during the weekend.

Tropical Cyclone Freddy will move around the northern side of a high pressure system over the South Indian Ocean. The high pressure system will steer Freddy toward the west during the next several days. On its anticipated track, the center of Tropical Cyclone Freddy could be south of Cocos Islands in 36 hours. The core of Freddy and the strongest winds will pass south of Cocos Islands. Bands on the northern edge of Freddy’s circulation could bring gusty winds and locally heavy rain to the Cocos Islands.

Elsewhere over the South Indian Ocean, Tropical Cyclone Dingani moved south-southeast of Diego Garcia. At 10:00 a.m. EST on Saturday the center of Tropical Cyclone Dingani was located at latitude 15.6°S and longitude 77.8°E which put it about 740 miles (1195 km) south-southeast of Diego Garcia. Dingani was moving toward the west at 14 m.p.h. (22 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 988 mb.

Tropical Cyclone Dingani Forms over South Indian Ocean

Tropical Cyclone Dingani formed over the South Indian Ocean south-southeast of Diego Garcia on Thursday morning. At 4:00 a.m. EST on Thursday the center of Tropical Cyclone Dingani was located at latitude 16.9°S and longitude 88.6°E which put it about 1305 miles (2110 km) south-southeast of Diego Garcia. Dingani was moving toward the west-southwest 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 997 mb.

A low pressure system over the South Indian Ocean strengthened on Thursday morning and Meteo France La Reunion designated the system as Tropical Cyclone Dingani. The distribution of thunderstorms in Tropical Cyclone Dingani was asymmetrical. Thunderstorms were occurring in bands in the western side of Dingani’s circulation. Bands in the other parts of Dingani consisted primarily of showers and lower clouds. Tropical Cyclone Dingani was moving under the western end of an upper level ridge over the Southeast Indian Ocean. The upper level ridge was producing northeasterly winds that were blowing toward the top of Dingani’s circulation. Those winds were causing moderate vertical wind shear and the wind shear was contributing to the asymmetrical distribution of thunderstorms. Winds to tropical storm force extended out 75 miles (120 km) from the center of Tropical Cyclone Dingani.

Tropical Cyclone Dingani will move through an environment somewhat favorable for intensification during the next 36 hours. Dingani will move over over water where the Sea Surface Temperatures are near 27˚C. However, the upper level ridge will continue to cause moderate vertical wind shear. Tropical Cyclone Dingani could strengthen gradually during the next 36 hours, if the upper level winds do not get any stronger. If the upper level winds get stronger, then Dingani will not intensify.

Tropical Cyclone Dingani will move around the northern part of a high pressure system over the South Indian Ocean. The high pressure system will steer Dingani toward the west during the next 36 hours. On its anticipated track, Tropical Cyclone Dingani will pass far south of Diego Garcia.

Elsewhere over the South Indian Ocean, Tropical Cyclone Freddy moved farther away from Western Australia. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Freddy was located at latitude 15.4°S and longitude 109.3°E which put it about 560 miles (900 km) north-northwest of Learmonth, Australia. Freddy was moving toward the west at 8 m.p.h. (13 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 990 mb.

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 Freddy Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Freddy rapidly intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean north of Western Australia on Monday night. At 10:00 p.m. EST on Monday the center of Tropical Cyclone Freddy was located at latitude 14.1°S and longitude 117.2°E which put it about 400 miles (645 km) northwest of Broome, Australia. Freddy was moving toward the southwest at 10 m.p.h. (16 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 972 mb.

Tropical Cyclone Freddy rapidly intensified to the equivalent of a hurricane/typhoon on Monday. The inner end of a rainband wrapped completely around the center of Freddy’s circulation. A small circular eye formed at the center of Tropical Cyclone Freddy. 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 core of Freddy’ circulation. Storms near the core 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 Freddy. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation.

Tropical Cyclone Freddy will move through an environment favorable for intensification during the next 36 hours. Freddy will move over over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis of an upper level ridge over the South Indian Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Cyclone Freddy will intensify during the next 36 hours and it is likely to strengthen rapidly at times. Freddy could intensify to the equivalent of a major hurricane during the next 36 hours.

Tropical Cyclone Freddy will move around the northwestern part of a high pressure system over Western Australia. The high pressure system will steer Freddy toward the west-southwest during the next 36 hours. On its anticipated track, Tropical Cyclone Freddy will stay northwest of Western Australia.

Tropical Cyclone Freddy Develops Rapidly North of Western Australia

Tropical Cyclone Freddy developed rapidly over the South Indian Ocean north of Western Australia on Monday morning. At 10:00 a.m. EST on Monday the center of Tropical Cyclone Freddy was located at latitude 12.8°S and longitude 118.4°E which put it about 440 miles (710 km) northwest of Broome, Australia. Freddy was moving toward the southwest 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 992 mb.

The circulation around a low pressure system over the South Indian Ocean north of Western Australia strengthened rapidly on Monday morning and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Freddy. The inner end of a rainband wrapped around the southern and western sides of the center of Freddy’s circulation. Other bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Freddy. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical cyclone. The circulation around Tropical Cyclone Freddy was small. Winds to tropical storm force extended out 70 miles (110 km) from the center of Freddy.

Tropical Cyclone Freddy will move through an environment favorable for intensification during the next 36 hours. Freddy will move over over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis of an upper level ridge over the South Indian Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Cyclone Freddy will intensify during the next 36 hours and it could strengthen rapidly at times. Freddy is likely to intensify to the equivalent of a hurricane/typhoon during the next 36 hours. It could strengthen to the equivalent of a major hurricane later this week.

Tropical Cyclone Freddy will move around the northwestern part of a high pressure system over Western Australia. The high pressure system will steer Freddy toward the west-southwest during the next 36 hours. On its anticipated track, Tropical Cyclone Freddy will stay north of Western Australia.

Elsewhere over the South Indian Ocean, a Tropical Low (also designated as Invest 94S) was east of Cocos Islands. At 10:00 a.m. EST on Monday the center of the Tropical Low was located at latitude 12.5°S and longitude 99.9°E which put it about 210 miles (335 km) east of Cocos Islands. The Tropical Low was moving toward the southeast at 10 m.p.h. (16 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 998 mb. The Tropical Low is forecast to turn toward the southwest and to strengthen to a tropical cyclone later this week.

Tropical Cyclone Dovi Moves Toward New Zealand

Tropical Cyclone Dovi moved toward New Zealand on Friday morning. At 10:00 a.m. EST on Friday the center of Tropical Cyclone Dovi was located at latitude 30.0°S and longitude 166.3°E which put it about 780 miles (1200 km) northwest of Auckland, New Zealand. Dovi was moving toward the south at 24 m.p.h. (39 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 969 mb.

Tropical Cyclone Dovi was located between New Caledonia and New Zealand on Friday morning. There was an eye with a diameter of 25 miles (40 km) at the center of Dovi’s circulation. The eye was surrounded by a broken ring of thunderstorms. The strongest thunderstorms were occurring in the eastern half of the ring. There were breaks in the northwestern part of the ring of storms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Dovi. 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 50 miles (80 km) from the center of Dovi. Winds to tropical storm force extended out 250 miles (400 km) from the center of circulation.

Tropical Cyclone Dovi will move into an environment that is unfavorable for a tropical cyclone. Dovi will move over water where the Sea Surface Temperatures are near 23˚C. An upper level trough centered east of Australia will produce strong northwesterly winds that will blow toward the top of Dovi’s circulation. Those winds will cause strong vertical wind shear. The combination of colder water and strong vertical wind shear will cause Tropical Cyclone Dovi to make a transition to a strong extratropical cyclone.

The upper level trough east of Australia will steer Tropical Cyclone Dovi toward the southeast during the next 36 hours. On its anticipated track Dovi will move across New Zealand during the weekend. Tropical Cyclone Dovi will be a strong extratropical cyclone when it crosses New Zealand. Dovi will bring strong winds and locally heavy rain to parts of New Zealand. The strongest winds and heaviest rain will occur in northern New Zealand.

Tropical Cyclone Diane Passes South of Rodrigues

Tropical Cyclone Diane passed south of Rodrigues on Saturday.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Diane was located at latitude 22.2°S and longitude 64.7°E which put it about 190 miles (305 km) south-southeast of Port Mathurin, Maritius.  Diane was moving toward the east-southeast at 23 m.p.h. (37 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 Diane brought winds to tropical storm force when it passed south of Rodrigues.  Diane also caused winds to tropical storm force over Mauritius earlier on Saturday.  A weather station at Le Morne on Mauritius measured a wind speed of 49 m.p.h. (79 km/h).  Several other weather stations on Mauritius including one at the international airport also reported winds to tropical storm force.

Tropical Cyclone Diane will move through an environment only marginally favorable for intensification.  Diane will move over water where the Sea Surface Temperature is near 27°C.  An upper level trough east of Madagascar will produce northwesterly winds which will blow toward the top of the tropical cyclone.  Those winds will cause moderate vertical wind shear which will inhibit intensification.  Tropical Cyclone Diane could strengthen a little more during the next 12 hours, but the wind shear will cause weakening in a day or two.

The upper level trough will steer Tropical Cyclone Diane toward the east-southeast during the next 24 to 36 hours.  On its anticipated track Diane will move quickly away from Rodrigues

Elsewhere over the South Indian Ocean, Tropical Cyclone Esami was churning about 1000 miles (1600 km) east of Tropical Cyclone Diane.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Esami was located at latitude 25.9°S and longitude 74.8°E which put it about 1160 miles (1875 km) east-southeast of Port Louis, Mauritius.  Esami was moving toward the southeast at 13 m.p.h. (20 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.

Tropical Cyclone Riley Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Riley strengthened into the equivalent of a hurricane/typhoon on Friday.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Riley was located at latitude 17.2°S and longitude 116.9°E which put it about 415 miles (675 km) north-northeast of Learmonth, Australia.  Riley was moving toward the west 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 976 mb.

Tropical Cyclone Riley strengthened, but the distribution of thunderstorms was asymmetrical.  The strongest winds were occurring in a band the curled around the northern half of the center of circulation.  Storms in the band were generating upper level divergence which was pumping mass away from the tropical cyclone.  Other bands of showers and thunderstorms were present in the western half of the circulation, but the bands in the eastern half of Tropical Cyclone Riley consisted primarily of showers and lower clouds.  Winds to hurricane/typhoon force extended out about 35 miles (55 km) from the center of circulation and they were occurring mainly north of the center of Riley.  Winds to tropical storm force extended out about 130 miles (215 km) from the center.

Tropical Cyclone Riley was moving around the northwestern part of an upper level ridge.  The ridge was producing easterly winds which were blowing toward the top of the circulation.  Those winds appeared to converge with the upper level divergence on the east side of Riley to produce sinking motion in that part of the tropical cyclone.  The sinking motion was bringing drier air to the lower levels and it appeared to suppressing convection in that region.

Tropical Cyclone Riley may be close to its peak intensity.  Riley is currently over water where the Sea Surface Temperature is near 28°C, but it will move over cooler water during the next few days.  The upper level ridge will continue to produce easterly winds which will blow toward the top of the circulation.  Those winds could strengthen which would cause more vertical wind shear.  Riley could intensify during the next 24 hours, but it is more likely to gradually weaken during the next two or three days.

The ridge will steer Tropical Cyclone Riley toward the west-southwest during the next few days.  On its anticipated track Riley will remain north of the coast of Western Australia,  However, watches and warnings are in effect for portions of the coast in case the Tropical Cyclone Riley moves more toward the south.  A Tropical Cyclone Warning is in effect for the portion of the coast from Whim Creek to Onslow including Karratha and Dampier.  A Tropical Cyclone Watch is in effect from Onslow to Exmouth.

Elsewhere around Australia, a Tropical Low was dropping heavy rain over portions of northern Queensland.  At 1:00 p.m. EST the center of the Tropical Low was located at latitude 13.8°S and longitude 141.3°E which put it about 80 miles (125 km) north-northwest of Pormpuraaw, Australia.  It was moving toward the southeast at 6 m.p.h. (10 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 1002 mb.  Locally heavy rain could cause floods in parts of northern Queensland.

Tropical Low Prompts Warning for Northern Queensland

A tropical low over the Gulf of Carpentaria prompted the issuance of warnings and watches for northern Queensland on Thursday.  A Tropical Cyclone Warning was in effect for the portion of the coast from Mapoon to Karumba.  A Tropical Cyclone Watch was in effect for the portion of the coast from Karumba to the border between Queensland and the Northern Territory including Mornington Island.

At 7:00 p.m. EST on Thursday the center of the tropical low was located at latitude 13.0°S and longitude 139.9°E which put it about 135 miles (220 km) west of Weipa, Australia.  It was moving toward the north at 5 m.p.h. (8 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 1002 mb.

The circulation around the tropical low exhibited more organization on Thursday.  A band of showers and thunderstorms wrapped around the western and northern sides of the center of circulation.  Other bands of showers and thunderstorms were developing over the Gulf of Carpentaria.  Storms near the center of circulation began to generate upper level divergence which was pumping mass away in outflow channels to the northwest and southeast of the tropical low.

The tropical low will move through an environment favorable for intensification.  It will move over water where the Sea Surface Temperature is near 30°C.  The tropical low will be in an area where the upper level winds are weaker and the vertical wind shear will be limited.  The tropical low is likely to intensify during the next 24 to 36 hours and it is forecast to become a named tropical cyclone.

The tropical low is under the northeastern portion of an upper level low.  It is in a small region where the steering winds are weaker and the tropical low meandered over the eastern Gulf of Carpentaria on Thursday.  Northerly winds blowing around the upper level low are forecast to steer the tropical low toward the south during the next day or two.  On its anticipated path the tropical low is expected to move over the eastern Gulf of Carpentaria near the coast of Queensland.  If the tropical low follow its anticipated track, it will make landfall on the south coast of the Gulf of Carpentaria in about 48 hours.  However, any eastward deviation would bring the tropical low inland over Queensland much sooner.

Elsewhere, Tropical Cyclone Riley strengthened northwest of Australia.  At 7:00 p.m. EST on Thursday the center of Tropical Cyclone Riley was located at latitude 16.5°S and longitude 118.8°E which put it about 265 miles (425 km) north of Port Hedland, Australia.  Riley was moving toward the west at 4 m.p.h. (6 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 985 mb.  A Tropical Cyclone Watch was in effect for the portion of the coast from Whim Creek to Onslow, Australia including Karratha and Dampier.

Tropical Cyclone Riley Forms West of Australia

Tropical Cyclone Riley formed west of Australia on Wednesday.  At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Riley was located at latitude 16.7°S and longitude 121.2°E which put it about 110 miles (175 km) northwest of Broome, Australia.  Riley was moving toward the west-southwest 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 997 mb.

The circulation around a tropical low off the coast of Western Australia strengthened on Wednesday and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Riley.  A band of thunderstorms wrapped clockwise from northwest to southeast around the center of circulation.  Additional bands of showers and thunderstorms were developing around the western side of the circulation which was over the open water of the south Indian Ocean.  The bands on the eastern side of the circulation were weaker, but portions of those bands were still over Western Australia.  Thunderstorms around the center of circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.

Tropical Cyclone Riley will move through an environment favorable for intensification during the next several days.  Riley will move over water where the Sea Surface Temperature is near 30°C.  It will move through an area where the upper level winds are weak and there will not be much vertical wind shear.  Tropical Cyclone Riley is likely to intensify steadily and it could intensify rapidly once an eye forms and the inner core is well developed.  Tropical Cyclone Riley is likely to strengthen into the equivalent of a hurricane/typhoon within 24 to 36 hours.

Tropical Cyclone Riley will move along the northwestern edge of a subtropical ridge during the next 48 to 72 hours.  The ridge will steer Riley in a general west-southwesterly direction.  On its anticipated track Tropical Cyclone Riley will move parallel to the coast of Western Australia.  However, a southward deviation of the track could bring Riley closer to the coast.