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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 Hola Passes Near Iles Loyaute

Tropical Cyclone Hola passed near the Iles Loyaute (Loyalty Islands) on Friday.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Hola was located at latitude 20.9°S and longitude 168.0°E which put it about 175 miles (280 km) northeast of Noumea, New Caledonia.  Hola was moving toward the southeast at 19 m.p.h. (31 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 969 mb.

The circulation of Tropical Cyclone Hola exhibited signs of weakening on Friday.  The eye appeared and disappeared intermittently.  There were occasional breaks in the rings of thunderstorms around the intermittent eye.  The distribution of rainbands became more asymmetrical.  All of the stronger bands were south and east of the center of circulation.  The bands north and west of the center consisted primarily of showers and low clouds.  An upper level trough off the east coast of Australia was producing northwesterly winds which were blowing toward the top of the circulation.  Those winds were also causing moderate vertical wind shear and they may have tilted the upper portion of the circulation toward the southeast.

Tropical Cyclone Hola will weaken during the next few days.  Hola will initially pass over water where the Sea Surface Temperature is near 28°C.  However, the upper level trough will continue to cause moderate vertical wind shear which will weaken Hola.  Tropical Cyclone Hola will also move over colder water when it moves farther to the south.  The colder water and vertical wind shear will cause the structure of Tropical Cyclone Hola to transition gradually to an extratropical cyclone during the next several days.

The upper level trough is pushing Tropical Cyclone Hola toward the southeast and a general southeasterly motion will continue.  On its anticipated track Tropical Cyclone Hola will move away from the Iles Loyaute and New Caledonia.  Hola could approach northern New Zealand in a couple of days.

The strongest winds and heavy rain were occurring on the eastern side of Tropical Cyclone Hola.  Hola will continue to bring gusty winds and locally heavy rain to the Iles Loyaute until it moves away.  It should have minimal impacts on New Caledonia.  Tropical Cyclone Hola could make landfall on the North Island of New Zealand in two or three days.  It could be a strong extratropical cyclone at that time and it could bring strong wind and heavy rain to parts of northern New Zealand.

Tropical Cyclone Hola Stalls Between Vanuatu and New Caledonia

Tropical Cyclone Hola stalled between Vanuatu and New Caledonia on Thursday.  At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Hola was located at latitude 18.4°S and longitude 165.5°E which put it about 200 miles (320 km) west of Port Vila, Vanuatu.  Hola was moving toward the south at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 961 mb.

Tropical Cyclone Hola weakened slightly while it move slowly between Vanuatu and New Caledonia.  The small eye was no longer visible on satellite images.  Thunderstorms were still occurring in the core of the circulation.  Most of the bands of showers and thunderstorms were in the eastern half of the circulation.  There were fewer thunderstorms west of the center of circulation.  The wind field exhibited a similar asymmetrical distribution.  Winds to hurricane/typhoon force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) in the eastern half of the circulation and about 100 miles (160 km) in the western half of the circulation.

Tropical Cyclone Hola will move through an environment marginally favorable for intensification on Friday.  Hola will move over water where the Sea Surface Temperature is near 30°C.  An upper level trough east of Australia will produce northwesterly winds which will blow toward the top of the circulation.  Those winds will cause increasing vertical wind shear and the shear could become strong enough to inhibit intensification.  Tropical Cyclone Hola could intensify during the next 12 to 24 hours, but it will begin to weaken when the shear increases.

Tropical Cyclone Hola is near the western end of a subtropical ridge and it was in a region where the steering winds were weak on Thursday.  The upper level trough east of Australia will start to steer Hola toward the southeast on Friday.  On its anticipated track the center of Tropical Cyclone Hola could approach the Iles Loyaute (the Loyalty Islands) within 24 hours.  Hola will likely still be the equivalent of a hurricane/typhoon at that time.

Tropical Cyclone Hola Brings Wind and Rain to Vanuatu

Tropical Cyclone Hola brought strong winds and heavy rain to Vanuatu on Wednesday.  At 10:00 p.m. EST on Wednesday the center of Tropical Cyclone Hola was located at latitude 17.4°S and longitude 165.5°E  which put it about 180 miles (290 km) west of Port Vila, Vanuatu.  Hola was moving toward the west-southwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 959 mb.

Tropical Cyclone Hola intensified rapidly into the equivalent of a hurricane/typhoon on Wednesday.  A very small circular eye developed at the center of circulation.  A ring of strong thunderstorms formed around the eye and the strongest winds were occurring in that ring of storms.  Rainbands were revolving around the core of the Tropical Cyclone Hola.  The strongest rainbands were occurring in the eastern side of the circulation.  The rainbands were weaker in the western half of Hola.  Storms around the core of the circulation were generating strong upper level divergence which was pumping mass away to the east of the tropical cyclone.  The circulation of Tropical Cyclone Hola was fairly small.  Winds to hurricane/typhoon force extended out about 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out about 120 miles (195 km) from the center.

Tropical Cyclone Hola will move through an environment favorable for intensification for another 24 to 36 hours.  Hola will move over water where the Sea Surface Temperature is near 30°C.  It is moving under a region where the upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Hola is likely to intensify during the next 24 hours and it could become the equivalent of a major hurricane.

Tropical Cyclone Hola was moving around the northwestern end of a subtropical ridge which was steering the tropical cyclone toward the west-northwest.  Hola is forecast to turn more toward the south when it rounds the end of the ridge on Thursday.  It could move toward the southeast when it moves farther south.  On its anticipated track Tropical Cyclone Hola could approach New Caledonia and the Iles Loyaute in a little over 24 hours.

Rainbands in the eastern half of Tropical Cyclone Hola brought gusty winds and locally heavy rain to parts of Vanuatu on Wednesday.  Wind and rain could increase over New Caledonia and the Iles Loyaute by Friday.

Tropical Cyclone Hola Develops Over Vanuatu

Tropical Cyclone Hola developed over Vanuatu on Tuesday.  At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone Hola was located at latitude 16.2°S and longitude 168.1°E which put it near Ambrym and about 110 miles (180 km) north of Port Vila, Vanuatu.  Hola was moving toward the west-southwest at 6 m.p.h. (10 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.

A large area of showers and thunderstorms northwest of Fiji moved slowly westward toward Vanuatu during the past few days.  The system was designated Tropical Cyclone Hola when a center of circulation developed in the area of storms on Tuesday.  Thunderstorms formed on all sides of the center, but there were more thunderstorms on the western side of the center.  Bands of showers and storms were beginning to revolve around the core of the circulation.  The storms near the center were starting to generate upper level divergence which was pumping mass away from the center of circulation.

Tropical Cyclone Hola will move through an environment favorable for intensification during the next two or three days.  Hola will move over water where the Sea Surface Temperature is near 30°C.  The upper level winds over that area are weak and there is little vertical wind shear.  Tropical Cyclone Hola should intensify during the next 48 to 72 hours.  Rapid intensification could occur once the core of the circulation is fully organized.  Hola could strengthen into the equivalent of a hurricane/typhoon during the next 24 hours.  Hola could become the equivalent of a major hurricane within three days.

Tropical Cyclone Hola is moving near the northwestern end of a subtropical ridge which is steering Hola toward the west-southwest.  A slow motion toward the southwest is forecast during the next day or so while Hola rounds the northwestern end of the ridge.  Tropical Cyclone Hola will turn more toward the southeast after it rounds the subtropical ridge.  On its anticipated track the center of Tropical Cyclone Hola will move near Ambrym, Malekula, Paama, Lopevi, and Epi.  Hola is forecast to pass west of Port Vila, but it could be near New Caledonia and the Iles Loyaute in two or three days.

Tropical Cyclone Hola will strengthen as it moves slowly toward the southwest during the next 24 hours.  The stronger tropical cyclone will produce gusty winds and it will drop heavy rain over the central parts of Vanuatu.  Heavy rain will fall over Espiritu Santo, Maewo, Ambae, Pentecost, Malo, Ambrym, Paama, Lopevi, Tongoa, Epi, Emae, the Shepherd Islands, Nguna, Emao, and Efate.  Locally heavy rain could create the potential for floods in some of those locations.

Tropical Cyclones Winston and Tatiana Form over SW Pacific

A pair of tropical cyclones named Winston and Tatiana formed over the southwestern Pacific Ocean on Thursday.  At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Winston was located at latitude 18.4°S and longitude 171.6°E which put it about 445 miles (720 km) west of Suva, Fiji.  Winston was moving toward the south at 7 m.p.h. (11 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 974 mb.

At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Tatiana was located at latitude 17.3°S and longitude 159.0°E which put it about 620 miles (1000 km) northwest of Noumea, New Caledonia.  Tatiana was moving toward the east-southeast at 6 m.p.h. (10 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 982 mb.

Tropical Cyclone Winston is the stronger and more well organized storm.  It has a well developed eye surrounded by a ring of strong thunderstorms.  Winston is in a very favorable environment.  It is moving over water where the Sea Surface Temperatures are near 31°C.  There is an upper level ridge over Winston and so the upper level winds are light and divergence is occurring in all directions.  Winston is likely to continue to intensify rapidly on Friday and it could become the equivalent of a major hurricane.

Tropical Cyclone Tatiana is smaller and not as well organized.  Tatiana is moving over water where the Sea Surface Temperatures are near 30°C.  However the western end of the same upper level ridge that is over Winston is generating brisk northerly winds over the top of Tropical Cyclone Tatiana.  As a result, vertical wind shear is inhibiting upper level divergence to the north of the center of Tatiana and it is also tilting the circulation toward the south with height.  Wind shear is likely to prevent Tatiana from intensifying significantly.

A subtropical ridge is steering both Winston and Tatiana toward the south.  Tropical Cyclone Winston will pass west of Fiji, but it could come close enough to the extreme southeastern islands of Vanuatu to bring wind and rain to some of those islands.  Tropical Cyclone Tatiana is likely to pass west of New Caledonia, but it could bring rain and higher surf to the west coast of that island.