Category Archives: Australian Region

Tropical Cyclone Alfred Churns over the Coral Sea

Tropical Cyclone Alfred continued to churn over the Coral Sea on Thursday. At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Alfred was located at latitude 19.4°S and longitude 155.5°E which put the center about 605 miles (980 km) north-northeast of Brisbane, Australia. Alfred was moving toward the south at 8 m.p.h. (13 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 950 mb.

Tropical Cyclone Alfred strengthened a little more as it churned over the Coral Sea on Thursday. A circular eye with a diameter of 20 miles (32 km) was present at the center of Alfred’s circulation. 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 Tropical Cyclone Alfred. Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone. The divergence of mass in the upper atmosphere was nearly equal to the convergence of mass in the lower atmosphere. The near balance of mass caused the surface pressure to remain nearly steady.

The circulation around Tropical Cyclone Alfred was large. Winds to hurricane/typhoon force extended out 105 miles (165 km) from the center of Alfred’s circulation. Winds to tropical storm force extended out 215 miles (345 km) from the center of Tropical Cyclone Alfred.

The Hurricane Intensity Index (HII) for Tropical Cyclone Alfred is 22.1. The Hurricane Size Index (HSI) is 29.3 and the Hurricane Wind Intensity Size Index (HWISI) is 51.4. Tropical Cyclone Alfred is similar in size and intensity to Hurricane Jeanne when Jeanne hit Florida in 2004.

Tropical Cyclone Alfred will move through an environment somewhat favorable for intensification during the next 24 hours. Alfred will move over water where where the Sea Surface Temperatures are near 29°C. It will move under the middle of an upper level ridge over the Coral Sea. The winds are weak near the middle of the upper level ridge and there will be little vertical wind shear. However, the circulation around Alfred seems to be nearly in balance with the surrounding environment. So, the intensity of Tropical Cyclone Alfred may not change much during the next 24 hours.

Tropical Cyclone Alfred will move around the western side of a high pressure system that is east of the Coral Sea. The high pressure system will steer Alfred toward the south during the next 24 hours. On its anticipated track, Tropical Cyclone Alfred will move parallel to the east coast of Australia. Alfred could move closer to the coast of Queensland during the weekend.

Tropical Cyclone Alfred Continues to Strengthen

Tropical Cyclone Alfred continued to strengthen over the Coral Sea on Wednesday. At 10:00 p.m. EST on Wednesday the center of Tropical Cyclone Alfred was located at latitude 17.0°S and longitude 155.5°E which put the center about 660 miles (1050 km) north-northeast of Brisbane, Australia. Alfred was moving toward the south at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h). The minimum surface pressure was 962 mb.

Tropical Cyclone Alfred continued to strengthen over the Coral Sea on Wednesday. A very small circular eye was visible at the center of Alfred’s circulation on satellite images. 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 Tropical Cyclone Alfred. Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass caused the surface pressure to decrease.

The size of the circulation around Tropical Cyclone Alfred increased when Alfred strengthened on Wednesday. Winds to hurricane/typhoon force extended out 60 miles (95 km) from the center of Alfred’s circulation. Winds to tropical storm force extended out 200 miles (325 km) from the center of Tropical Cyclone Alfred.

The Hurricane Intensity Index (HII) for Tropical Cyclone Alfred is 19.2. The Hurricane Size Index (HSI) is 22.7 and the Hurricane Wind Intensity Size Index (HWISI) is 41.9. Tropical Cyclone Alfred is similar in size and intensity to Hurricane Gustav when Gustav hit Louisiana in 2008.

Tropical Cyclone Alfred will move through an environment favorable for intensification during the next 24 hours. Alfred will move over water where where the Sea Surface Temperatures are near 29°C. It will move under the middle of an upper level ridge over the Coral Sea. The winds are weak near the middle of the upper level ridge and there will be little vertical wind shear. Tropical Cyclone Alfred is likely to intensify during the next 24 hours unless an eyewall replacement cycle occurs. If the inner end of a rainband wraps around the existing eye and eyewall, then concentric eyewalls will form. If concentric eyewalls form, then an eyewall replacement cycle will cause Alfred to weaken.

Tropical Cyclone Alfred will move around the western side of a high pressure system that is over Vanuatu. The high pressure system will steer Alfred toward the south during the next 24 hours. On its anticipated track, Tropical Cyclone Alfred will move parallel to the east coast of Australia. Alfred could move closer to the coast of Queensland by the weekend.

Tropical Cyclone Bianca Weakens Rapidly

Tropical Cyclone Bianca weakened rapidly over the South Indian Ocean west of Australia on Wednesday. At 4:00 a.m. EST on Wednesday the center of Tropical Cyclone Bianca was located at latitude 25.7°S and longitude 102.7°E which put the center about 730 miles (1175 km) west of Carnarvon, Australia. Bianca was moving toward the south-southeast at 7 m.p.h. (11 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 999 mb.

Tropical Cyclone Bianca weakened rapidly over the South Indian Ocean west of Australia on Wednesday. An upper level trough west of Australia produced strong northwesterly winds that blew across the top of Tropical Cyclone Bianca. Those winds caused strong vertical wind shear. The vertical wind shear blew the upper part of Bianca’s circulation to the southeast of the circulation in the lower levels.

The circulation of Tropical Cyclone Bianca consisted of bands of showers and lower clouds that were revolving around the low level center of circulation. Strong vertical wind shear was blowing the tops off of clouds that rose higher into the atmosphere.

The circulation around Tropical Cyclone Bianca was small. Winds to tropical storm force extended out 100 miles (160 km) from the center of Bianca’s circulation.

Tropical Cyclone Bianca will move through an environment that will be unfavorable for intensification during the next 24 hours. Bianca will move over water where where the Sea Surface Temperatures are near 23°C. It will move under the eastern side of an upper level trough over the South Indian Ocean. The upper level trough will continue to produce strong northwesterly winds that will blow across the top of Bianca’s circulation. Those winds will cause strong vertical wind shear. Cooler water and strong vertical wind shear will cause Tropical Cyclone Bianca to continue to weaken during the next 24 hours.

Since the circulation around Tropical Cyclone Bianca exists only in the lower levels of the atmosphere, Bianca will be steered by the weather features near the surface. Bianca will move around the northern side of a high pressure system over the South Indian Ocean. The high pressure system will steer Bianca toward the west during the next 24 hours. On its anticipated track, Tropical Cyclone Bianca will move farther away from Western Australia.

Tropical Cyclone Alfred Meanders over the Coral Sea

Tropical Cyclone Alfred meandered over the Coral Sea on Tuesday. At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Alfred was located at latitude 15.0°S and longitude 155.0°E which put the center about 850 miles (1370 km) north of Brisbane, Australia. Alfred was moving toward the south at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 975 mb.

Tropical Cyclone Alfred continued to intensify gradually on Tuesday. The inner end of a rainband wrapped around the center of Alfred’s circulation. An eye appeared to be forming at the center of Tropical Cyclone Alfred. A ring of thunderstorms surrounded the developing eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Alfred’s circulation. Storms near the core of Alfred generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Alfred was small. Winds to hurricane/typhoon force extended out 15 miles (25 km) in the southern side of Alfred’s circulation. Winds to tropical storm force extended out 80 miles (130 km) from the center of Tropical Cyclone Alfred.

Tropical Cyclone Alfred will move around the western side of a high pressure system that is over Vanuatu. The high pressure system will steer Alfred slowly toward the south during the next 24 hours. On its anticipated track, Tropical Cyclone Alfred will move parallel to the east coast of Australia. Alfred could move closer to the coast of Queensland by the weekend.

Tropical Cyclone Bianca Strengthens to Equivalent of Major Hurricane

Tropical Cyclone Bianca strengthened to the equivalent of a major hurricane on Monday night. At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Bianca was located at latitude 22.3°S and longitude 102.0°E which put the center about 765 miles (1235 km) west of the Exmouth, Australia. Bianca was moving toward the south-southwest at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h). The minimum surface pressure was 962 mb.

Tropical Cyclone Bianca strengthened to the equivalent of a major hurricane over the South Indian Ocean west of Australia on Monday night. A circular eye with a diameter of 20 miles (32 km) was at the center of Bianca’s circulation. 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 revolved around the center of Bianca’s circulation. Storms near the center of Bianca generated upper level divergence that pumped mass away from the tropical cyclone.

The circulation around Tropical Cyclone Bianca was small. Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Bianca’s circulation. Winds to tropical storm force extended out 100 miles (160 km) from the center of Tropical Cyclone Bianca.

The Hurricane Intensity Index (HII) for Tropical Cyclone Bianca was 20.6. The Hurricane Size Index (HSI) was 9.3 and the Hurricane Wind Intensity Size Index (HWISI) was 29.9.

Tropical Cyclone Bianca will move into an environment that will become unfavorable for intensification during the next 24 hours. Bianca will move over water where where the Sea Surface Temperatures are near 26°C. It will move under the eastern side of an upper level trough over the South Indian Ocean. The upper level trough will produce northwesterly winds that will blow toward the top of Bianca’s circulation. Those winds will cause the vertical wind shear to increase. Tropical Cyclone Bianca will weaken when the vertical wind shear increases.

Tropical Cyclone Bianca will move around the western part of a high pressure system over the South Indian Ocean. The high pressure system will steer Bianca toward the south during the next 24 hours. On its anticipated track, Tropical Cyclone Bianca will move parallel to the coast of Western Australia.

Tropical Cyclone Alfred Spins over the Coral Sea

Tropical Cyclone Alfred continued to spin over the Coral Sea on Monday. At 10:00 p.m. EST on Monday the center of Tropical Cyclone Alfred was located at latitude 14.6°S and longitude 154.5°E which put the center about 670 miles (1085 km) north of Brisbane, Australia. Alfred was moving toward the south at 4 m.p.h. (6 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 984 mb.

Tropical Cyclone Alfred strengthened to the equivalent of a hurricane/typhoon as it spun over the Coral Sea on Monday. The inner end of a rainband wrapped around the center of Alfred’s circulation. A small circular eye was evident at the center of Tropical Cyclone Alfred on visible satellite images. 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 Tropical Cyclone Alfred. Storms near the center of Alfred generated upper level divergence that pumped mass away from the tropical cyclone.

The circulation around Tropical Cyclone Alfred was small. Winds to hurricane/typhoon force extended out 15 miles (25 km) in the southern side of Alfred’s circulation. Winds to tropical storm force extended out 60 miles (95 km) from the center of Tropical Cyclone Alfred.

Tropical Cyclone Alfred will move through an environment favorable for intensification during the next 24 hours. Alfred will move over water where where the Sea Surface Temperatures are near 29°C. It will move under the western part of an upper level ridge over the Coral Sea. The upper level ridge will produce northeasterly winds that will blow toward the top of Alfred’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Tropical Cyclone Alfred is likely to intensify during the next 24 hours.

Tropical Cyclone Bianca Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Bianca strengthened to the equivalent of a hurricane/typhoon over the South Indian Ocean on Sunday night. At 4:00 a.m. EST on Monday the center of Tropical Cyclone Bianca was located at latitude 19.3°S and longitude 103.3°E which put the center about 645 miles (1040 km) southeast of the Cocos Islands. Bianca was moving toward the southwest at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 985 mb.

Tropical Cyclone Bianca rapidly intensified to the equivalent of a hurricane/typhoon over the South Indian Ocean southeast of the Cocos Islands during Sunday night. The inner end of a rainband wrapped around the center of Bianca’s circulation. A circular eye formed at the center of Tropical Cyclone Bianca. 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 revolved around the center of Bianca’s circulation. Storms near the center of Bianca generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Bianca was small. Winds to hurricane/typhoon force extended out 20 miles (3o km) from the center of Bianca’s circulation. Winds to tropical storm force extended out 75 miles (120 km) from the center of Tropical Cyclone Bianca.

Tropical Cyclone Bianca will move through an environment favorable for intensification during the next 24 hours. Bianca will move over water where where the Sea Surface Temperatures are near 27°C. It will move under the middle of an upper level ridge over the South Indian Ocean. The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear. Tropical Cyclone Bianca is likely to continue to intensify during the next 24 hours.

Tropical Cyclone Bianca will move around the northwestern part of a high pressure system over the South Indian Ocean. The high pressure system will steer Bianca toward the southwest during the next 24 hours. On its anticipated track, Tropical Cyclone Bianca will remain far to the southeast of the Cocos Islands.

Tropical Cyclone Alfred Forms over the Coral Sea

Tropical Cyclone Alfred formed over the Coral Sea on Sunday. At 4:00 a.m. EST on Sunday the center of Tropical Cyclone Alfred was located at latitude 14.3°S and longitude 153.7°E which put the center about 560 miles (900 km) east-northeast of Cairns, Australia. Alfred was moving toward the east 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.

A low pressure system over the Coral Sea strengthened on Sunday and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Alfred. The circulation around Tropical Cyclone Alfred exhibited more organization on Sunday. More thunderstorms formed near the center of Alfred’s circulation. More thunderstorms also developed in bands revolving around the center of Tropical Cyclone Alfred. Storms near the center of Alfred generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Alfred was fairly large. Winds to tropical storm force extended out 180 miles (290 km) from the center of Alfred’s circulation.

Tropical Cyclone Alfred will move around the southern side of a high pressure system that is near the Equator. The high pressure system will steer Alfred toward the east during the next 24 hours. On its anticipated track, Tropical Cyclone Alfred will move farther away from Australia. Alfred is like to start to move toward the south early next week.

Elsewhere, Tropical Cyclone Bianca formed over the South Indian Ocean northwest of Australia. At 4:00 a.m. EST on Sunday the center of Tropical Cyclone Bianca was located at latitude 17.0°S and longitude 106.9°E which put the center about 590 miles (950 km) northwest of Exmouth, Australia. Bianca 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 998 mb.

Tropical Cyclone Zelia Brings Wind and Rain to Western Australia

Tropical Cyclone Zelia brought wind and rain to Western Australia on Friday. At 7:00 a.m. EST on Friday the center of Tropical Cyclone Zelia was located at latitude 21.1°S and longitude 119.6°E which put the center about 10 miles (20 km) west-northwest of Marble Bar, Australia. Zelia was moving toward the south-southeast at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h). The minimum surface pressure was 965 mb.

The center of Tropical Cyclone Zelia made landfall on the coast of Western Australia about 45 miles (75 km) northeast of Port Hedland on Thursday night. Zelia was the equivalent of a major hurricane at the time of landfall. The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).

At the time of landfall winds to hurricane/typhoon force extended out 40 miles (65 km) from the center of Zelia’s circulation. Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Zelia.

The Hurricane Intensity Index (HII) for Tropical Cyclone Zelia was 25.1 . The Hurricane Size Index (HSI) was 13.9 and the Hurricane Wind Intensity Size Index (HWISI) was 39.0. Tropical Cyclone Zelia was similar in size and intensity to Hurricane Harvey when Harvey hit Texas in 2017.

Tropical Cyclone Zelia brought strong winds and heavy rain to parts of Western Australia east of Port Hedland. A weather station in Port Hedland reported a sustained wind speed of 50 m.p.h. (80 km/h). The weather station reported a wind gust of 75 m.p.h. (120 km/h). The weather station also reported 6.14 inches (156 mm) of rain.

A Flood Warning is in effect for the De Grey River. A Flood Warning is in effect for the Pilbara coastal Rivers.

Flood Watches are in effect for the Onslow coast, the Fortescue River, the Ashburton River, the Gascoyne River, and parts of the Sandy Desert.

Tropical Cyclone Zelia will move around the northwestern side of a high pressure system over Australia. The high pressure system will steer Zelia toward the south during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Zelia will pass between Nullagine and Munjina.

Tropical Cyclone Zelia will weaken steadily as it moves inland over Western Australia. Zelia will continue to bring strong winds and heavy rain to parts of Western Australia as it weakens. Heavy rain could cause additional flooding in some locations.

Tropical Cyclone Zelia Approaches Coast of Western Australia

Tropical Cyclone Zelia was approaching the coast of Western Australia near Port Hedland on Thursday night. At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Zelia was located at latitude 19.8°S and longitude 118.7°E which put the center about 55 miles (90 km) north of Port Hedland, Australia. Zelia was moving toward the south-southeast at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 938 mb.

Concentric eyewalls developed at the center of Tropical Cyclone Zelia on Thursday. The inner end of a rainband wrapped around the original eye and eyewall. The inner eyewall had a diameter of 15 miles (24 km). The outer eyewall had a diameter of 38 miles (61 km). The development of concentric eyewalls halted the intensification of Tropical Cyclone Zelia.

Bands of showers and thunderstorms were revolving around the concentric eyewalls at the center of Tropical Cyclone Zelia. Storms near the center of Zelia generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass in the upper levels was nearly the same as the inflow of mass in the lower levels of the atmosphere. So, the surface pressure remained fairly constant.

The circulation around Tropical Cyclone Zelia was symmetrical. Winds to hurricane/typhoon force extended out 40 miles (65 km) from the center of Zelia’s circulation. Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Zelia.

The Hurricane Intensity Index (HII) for Tropical Cyclone Zelia was 25.1. The Hurricane Size Index (HSI) was 13.9 and the Hurricane Wind Intensity Size Index (HWISI) was 39.0. Tropical Cyclone Zelia was similar in size and intensity to Hurricane Harvey when Harvey hit Texas in 2017.

Tropical Cyclone Zelia will move through an environment favorable for intensification during the next few hours. Zelia will move over water where where the Sea Surface Temperatures are near 30°C. It will move under the middle part of an upper level ridge that extends from Australia to the South Indian Ocean. The upper level winds are weak near the middle of the middle of the ridge and there will be little vertical wind shear. Even though Tropical Cyclone Zelia will move through a favorable environment, the concentric eyewalls are likely to prevent any significant intensification.

Tropical Cyclone Zelia will move around the northwestern side of a high pressure system over Australia. The high pressure system will steer Zelia slowly toward the south during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Zelia will make landfall on the coast of Western Australia near Port Hedland in a few hours.

Tropical Cyclone Zelia will bring strong winds and heavy rain to parts of Western Australia near Port Hedland.

A Warning is in effect for the portion of the coast from Wallal Downs to Roebourne. The Warning includes Port Hedland and De Grey. The Warning extends inland to Marble Bar, Millstream, Nullagine, Tom Price, and Paraburdoo.

Heavy rain is likely to cause floods in some locations.