Tag Archives: Willis Island

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 Owen Develops Over the Coral Sea

Tropical Cyclone Owen developed over the Coral Sea on Sunday.  Thunderstorms developed near the center of a tropical low over the Coral Sea and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Owen.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Owen was located at latitude 15.4°S and longitude 154.9°E which put it about 615 miles (990 km) east of Cairns, Australia.  Owen was moving toward the south 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 km/h).  The minimum surface pressure was 996 mb.

The circulation of Tropical Cyclone Owen became better organized on Sunday.  A band of thunderstorms wrapped around the eastern and southern sides of the center of circulation.  Additional bands of showers and thunderstorms were developing in the eastern half of the circulation.  Bands in the western half of Tropical Cyclone Owen consisted primarily of showers and lower clouds.  Storms near the center of circulation were generating upper level divergence which was pumping mass away to the east of the tropical cyclone.

Tropical Cyclone Owen will move through an environment marginally favorable for intensification during the next 24 to 36 hours.  Owen will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds will blow from the west.  Those winds will blow toward the top of the circulation and they are already causing moderate vertical wind shear.  The wind shear is the likely reason why most of the stronger thunderstorms are developing in the eastern half of the circulation.  The westerly winds will inhibit upper level divergence to the west of the tropical cyclone and the wind shear will limit intensification.  Tropical Cyclone Owen could strengthen during the next day or two, but the wind shear is likely to weaken Owen later this week.

Tropical Cyclone Owen will move north of a subtropical ridge in the middle troposphere.  The ridge is forecast to turn Owen toward the west and to steer the tropical cyclone toward the west during the next few days.  On its anticipated track Tropical Cyclone Owen is forecast to move slowly westward during the next several days.  Owen could be east of Willis Island in three or four days.