Tag Archives: Gabrielle

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.

Major Hurricane Dorian Moves Toward the Carolinas

Major Hurricane Dorian moved toward the Carolinas on Wednesday night.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Dorian was located at latitude 31.3°N and longitude 79.6°W which put it about 105 miles (170 km) south of Charleston, South Carolina.  Dorian was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 115 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (220 km/h).  The minimum surface pressure was 955 mb.

A Hurricane Warning was in effect for the portion of the coast from Savannah River, Georgia to the North Carolina/Virginia border including Albemarle and Pamlico Sounds.  A Hurricane Watch was in effect for the portion of the coast from the mouth of the St. Mary’s River, Florida to Savannah River, Georgia.  Tropical Storm Warnings were in effect for the portions of the coast from the mouth of the St. Mary’s River to Savannah River, Georgia and from the North Carolina/Virginia border to Chincoteague, Virginia.  A Tropical Storm Warning was also in effect for Chesapeak Bay south of Smith Point.  Tropical Storm Watches were in effect for the portion of the coast from Chincoteague, Virginia to Fenwick Island, Delaware, for Chesapeake Bay from Smith Point to Drum Point and for the Tidal Potomac south of Cobb Island.

Hurricane Dorian strengthened back into a major hurricane on Wednesday night as it moved over the warm water in the Gulf Stream.  A large eye with a diameter of 45 miles (75 km) became more circular and symmetrical.  The ring of thunderstorms surrounding the eye became continuous and a little thicker.  The strongest winds were occurring in that ring of storms.  Other bands of showers and thunderstorms revolving around the core of Hurricane Dorian also got stronger.  Storms around the core of Dorian generated upper level divergence which pumped mass away from the hurricane and the surface pressure decreased.

The circulation around Hurricane Dorian increased in size on Wednesday.  Winds to hurricane force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 200 miles (320 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 20.6.  The Hurricane Size Index (HSI) was 22.6 and the Hurricane Wind Intensity Size Index (HWISI) was 43.2.  Hurricane Dorian was capable of causing widespread major damage.

Hurricane Dorian will move through an environment favorable for intensification during the next 12 hours.  Dorian will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are weak and there is little vertical wind shear.  Hurricane Dorian could get a little stronger during the night.  An upper level trough over the central U.S. will move toward Hurricane Dorian on Thursday.  The upper level trough will produce southwesterly winds which will blow toward the top of the hurricane.  Those winds will cause the vertical wind shear to increase, which will cause Dorian to start to weaken.

Hurricane Dorian will move around the western end of a subtropical ridge over the western Atlantic Ocean.  The ridge will steer Dorian toward the north on Wednesday night.  The upper level trough will turn Hurricane Dorian toward the northeast on Thursday.  On its anticipated track Hurricane Dorian could approach the coast of South Carolina on Thursday morning.  Dorian will move along the coast of North Carolina on Thursday afternoon and Thursday night.

Even if the center of Hurricane Dorian stays just south of the coast of South Carolina and North Carolina, the large circulation means that locations near the coast are likely to get hurricane force winds.  Winds blowing water toward the coast could cause storm surges of 5 to 8 feet (1.5 to 2.5 meters) in some locations.  Dorian could also drop locally heavy rain and cause flash flooding  near the coast.

Elsewhere, Tropical Storm Fernand made landfall north of La Pesca, Mexico on Wednesday and Tropical Storm Gabrielle developed south of the Azores.  Ar 11:00 p.m. EDT on Wednesday the center of Tropical Depression Fernand was located at latitude 25.0°N and longitude 99.0°W which put it about 100 miles (160 km) west-northwest of La Pesca, Mexico.  Dorian was moving toward the west-northwest at 9 m.p.h. (15 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 1007 mb.

At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Gabrielle was located at latitude 21.5°N and longitude 34.4°W which put it about 1220 miles (1965 km) south-southwest of the Azores.  Gabrielle was moving toward the northwest at 7 m.p.h. (11 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 m/h).  The minimum surface pressure was 1002 mb.