Monthly Archives: April 2023

Tropical Storm Sanvu Spins Northeast of Chuuk

Tropical Storm Sanvu was spinning over the Western North Pacific Ocean northeast of Chuuk on Friday morning. At 5:00 a.m. EDT on Friday the center of Tropical Storm Sanvu was located at latitude 10.2°N and longitude 156.0°E which put it about 345 miles (555 km) northeast of Chuuk. Sanvu was moving toward the northwest at 3 m.p.h. (5 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 994 mb.

Tropical Storm Sanvu strengthened during Thursday. More thunderstorms developed near the center of Sanvu’s circulation. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Even though Tropical Storm Sanvu strengthened, the distribution of thunderstorms became more asymmetrical. Most of the thunderstorms were occurring in bands in the eastern side of Sanvu’s circulation. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Storm Sanvu.

Tropical Storm Sanvu will move through an environment that will become unfavorable for intensification during the next 24 hours. Sanvu will move over water where the Sea Surface Temperatures are near 29˚C. However, it will move under the northern side of an upper level ridge over the equatorial Western North Pacific. The ridge will produce westerly winds that will blow toward the top of Sanvu’s circulation. Those winds will cause the vertical wind shear to increase. Stronger vertical wind shear is likely to cause Tropical Storm Sanvu to start to weaken during the next 24 hours.

Tropical Storm Sanvu will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Sanvu toward the west-northwest during the next 24 hours. On its anticipated track, Tropical Storm Sanvu will pass north of Chuuk and Fananu during the weekend.

Tropical Storm Sanvu Develops Northwest of Pohnpei

Tropical Storm Sanvu developed over the Western North Pacific Ocean northwest of Pohnpei on Wednesday night. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Sanvu was located at latitude 9.3°N and longitude 156.8°E which put it about 165 miles (265 km) north-northwest of Pohnpei. Sanvu was moving toward the northwest at 16 m.p.h. (26 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 1000 mb.

Former Tropical Depression 01W strengthened on Wednesday night and the Japan Meteorological Agency designated the system as Tropical Storm Sanvu. The inner end of a rainband wrapped around the center of Sanvu’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 storm. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Tropical Storm Sanvu will move through an environment favorable for intensification during the next 24 hours. Sanvu will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis of an upper level ridge over the equatorial Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Storm Sanvu could intensify during the next 24 hours. Sanvu will move under the northern side of the upper level ridge on Friday and the vertical wind shear will increase. Tropical Storm Sanvu is likely to weaken when the wind shear increases.

Tropical Storm Sanvu will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Sanvu toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Sanvu will move farther away from Pohnpei. Sanvu will be northeast of Chuuk and Fananu on Thursday evening.

Tropical Depression 01W Forms South of Pohnpei

Tropical Depression 01W formed over the Western North Pacific Ocean south of Pohnpei on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression 01W was located at latitude 5.2°N and longitude 158.2°E which put it about 145 miles (235 km) south of Pohnpei. Tropical Depression 01W was moving toward the west-northwest 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 1004 mb.

A low pressure system over the Western North Pacific Ocean south of Pohnpei strengthened on Wednesday morning and both the Japan Meteorological Agency and the U.S. Joint Typhoon Warning Center classified the system as a tropical depression. The circulation around Tropical Depression 01W exhibited more organization on Wednesday morning. Bands of showers and thunderstorms were revolving around the center of Tropical Depression 01W. Storms near the center generated upper level divergence that pumped mass away from the tropical depression.

Tropical Depression 01W will move through an environment favorable for intensification during the next 24 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis of an upper level ridge over the equatorial Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Depression 01W is likely to intensify to a tropical storm during the next 24 hours.

Tropical Depression 01W will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer the tropical depression toward the northwest during the next 24 hours. On its anticipated track, Tropical Depression 01W will pass west of Pohnpei. The tropical depression could be northeast of Chuuk and east of Fananu on Thursday.

Tropical Cyclone Ilsa Brings Wind and Rain to Western Australia

Tropical Cyclone Ilsa continued to bring wind and rain to Western Australia on Friday morning. At 8:00 a.m. EDT on Friday the center of Tropical Cyclone Ilsa was located at latitude 22.4°S and longitude 125.0°E which put it about 180 miles (290 km) west of Kiwirrkurra, Australia. Ilsa was moving toward the east-southeast at 24 m.p.h. (39 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 994 mb.

Tropical Cyclone Isla continued to bring wind and rain to Western Australia after it made landfall on the coast near Pardoo Roadhouse on Thursday. Reports of the effects of Ilsa included pictures of damage to the Pardoo Roadhouse. A weather station in Telfer measured a sustained wind speed of 50 m.p.h. (80 km/h) when Tropical Cyclone Ilsa passed near it. The weather station also measured a wind gust of 77 m.p.h. (124 km/h) and it recorded 2.00 inches (51.0 mm) of rain. A weather station in Marble Bar measured 2.47 inches (62.8 mm) of rain dropped by Tropical Storm Ilsa.

A Minor Flood Warning was in effect for the De Grey River. A Flood Warning was in effect for the Sandy Desert. Flood Watches were in effect for Warburton District Rivers, Salt Lake District Rivers and the Western Desert.

The circulation around Tropical Cyclone Ilsa was still well defined on Friday morning even though it had been weakening over land for almost 24 hours. Bands of showers and thunderstorms were revolving around the center of Ilsa’s circulation. Winds to tropical storm force extended out 60 miles (95 km) in the northern side of Tropical Cyclone Ilsa.

Tropical Cyclone Ilsa will move around the southern side of a high pressure system over northern Australia. The high pressure system will steer Ilsa quickly toward the east-southeast during the next 24 hours. On its anticipated track the center of Tropical Cyclone Ilsa will pass near Kiwirrkurra and Alice Springs.

Tropical Cyclone Ilsa will continue to weaken as it moves over land. Ilsa will bring gusty winds and locally heavy rain to parts of Western Australia and the Northern Territory during the next 24 hours.

Tropical Cyclone Ilsa Hits Western Australia

The center of Tropical Cyclone Ilsa hit the coast of Western Australia just to the east of Pardoo Roadhouse on Thursday. At 11:00 a.m. EDT on Thursday the center of Tropical Cyclone Ilsa was located at latitude 19.9°S and longitude 119.7°E which put it about 10 miles (15 km) northeast of Pardoo Roadhouse, Australia. Ilsa was moving toward the southeast at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h). The minimum surface pressure was 926 mb.

A Tropical Cyclone Warning was in effect for the coast of Western Australia from Bidyadanga to Port Hedland. The Tropical Cyclone Warning extended inland to include De Grey, Marble Bar, Nullagine, Telfer, Parnngurr and Kunawarritji.

Tropical Cyclone Ilsa was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale at the time of landfall. A very small circular eye was present at the center of Ilsa’s circulation. The eye was surrounded by a ring of strong 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 Ilsa. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone.

A weather station at Bedout Island measured a sustained wind speed of 135 m.p.h. (218 km/h) when the western side of the eyewall of Tropical Cyclone Ilsa passed over it. The weather station also measured a wind gust of 178 m.p.h. (288 km/h).

Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Tropical Cyclone Ilsa at the time of landfall. Winds to tropical storm force extended out 140 miles (225 km) from the center. The Hurricane Intensity Index (HII) for Tropical Cyclone Ilsa was 31.6. The Hurricane Size Index (HSI) was 17.6 and the Hurricane Wind Intensity Size Index (HWISI) was 49.2. Tropical Cyclone Ilsa was similar in size and intensity to Hurricane Laura when Laura hit southwest Louisiana in 2020.

Tropical Cyclone Ilsa will move around the southern side of a high pressure system over northern Australia. The high pressure system will steer Ilsa toward the east-southeast during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Ilsa will pass near Telfer and Kiwirrkurra.

Although Tropical Cyclone Ilsa will weaken as it moves farther inland over Western Australia, it will take a while to spin down. Ilsa will bring strong winds and locally heavy rain to Western Australia. The strong winds will be capable of causing regional severe damage. Ilsa could also produce strong winds in De Grey and Telfer when it moves inland. Heavy rain could cause flash floods in some locations. Flood Warnings are in effect for the De Grey River and the Sandy Desert. Flood Watches are in effect for the West Kimberley, Western Desert, Warburton and Salt Lake Districts. Tropical Cyclone Ilsa could bring gusty winds to Kiwirrkurra during Friday.

Powerful Tropical Cyclone Ilsa Nears Western Australia

Powerful Tropical Cyclone Ilsa neared the coast of Western Australia on Thursday morning. At 5:00 a.m. EDT on Thursday the center of Tropical Cyclone Ilsa was located at latitude 19.1°S and longitude 119.1°E which put it about 75 miles (120 km) northwest of Pardoo Roadhouse, Australia. Ilsa was moving toward the south-southeast at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h). The minimum surface pressure was 926 mb.

A Tropical Cyclone Warning was in effect for the coast of Western Australia from Bidyadanga to Whim Creek. The Warning included Port Hedland. The Tropical Cyclone Warning extended inland to include De Grey, Marble Bar, Nullagine, Telfer and Parnngurr.

Tropical Cyclone Ilsa continued to intensify during Wednesday night, as it moved closer to the coast of Western Australia. A very small circular eye was present at the center of Ilsa’s circulation. The eye was surrounded by a ring of strong 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 Ilsa. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone. The removal of large quantities of mass was causing the surface pressure to continue to decrease.

A weather station at Bedout Island measured a sustained wind speed of 120 m.p.h. (104 kt or 193 km/h) as the core of Tropical Cyclone Ilsa was approaching it. The weather station also measured a wind gust of 144 m.p.h. (125 kt or 232 km/h).

The size of the circulation around Tropical Cyclone Ilsa increased as it intensified. Winds to hurricane/typhoon force extended out 50 miles (80 km) from the center of Tropical Cyclone Ilsa. Winds to tropical storm force extended out 140 miles (225 km) from the center. The Hurricane Intensity Index (HII) for Tropical Cyclone Ilsa was 31.6. The Hurricane Size Index (HSI) was 18.4 and the Hurricane Wind Intensity Size Index (HWISI) was 50.0. Tropical Cyclone Ilsa was similar in size and intensity to Hurricane Laura when Laura hit southwest Louisiana in 2020.

Tropical Cyclone Ilsa will move through an environment favorable for a powerful tropical cyclone during the next few hours. Ilsa will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the axis of an upper level ridge that extends from northern Australia to 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 Ilsa is likely to maintain its intensity until it reaches the coast of Western Australia.

Tropical Cyclone Ilsa will move around the western end of a high pressure system over western Australia. The high pressure system will steer Ilsa toward the southeast during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Ilsa is likely to make landfall on the coast of Western Australia near Pardoo Roadhouse in 6 hours. Ilsa will be the equivalent of a major hurricane when it makes landfall.

Tropical Cyclone Ilsa will bring very strong winds and locally heavy rain to Western Australia between De Grey and Wallal Downs. The strong winds will be capable of causing regional severe damage. Ilsa could also produce strong winds in De Grey and Telfer when it moves inland. Heavy rain could cause flash floods in some locations. Flood Warnings are in effect for the De Grey River and the Sandy Sesert. Flood Watches are in effect for the West Kimberley, Western Desert, Warburton and Salt Lake Districts. Tropical Cyclone Ilsa could also cause a storm surge of up to 10 to 15 feet (3 to 4.5 meters) along the portion of the coast near where the center makes landfall.

Tropical Cyclone Ilsa Strengthens to Equivalent of Cat. 4 Hurricane

Tropical Cyclone Ilsa strengthened to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Wednesday night. At 11:00 p.m. EDT on Wednesday the center of Tropical Cyclone Ilsa was located at latitude 18.1°S and longitude 119.2°E which put it about 175 miles (285 km) northwest of Wallal Downs, Australia. Ilsa was moving toward the south-southwest at 7 m.p.h. (11 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 942 mb.

A Tropical Cyclone Warning was in effect for the coast of Western Australia from south of Broome to Whim Creek. The Warning included Port Hedland. The Tropical Cyclone Warning extended inland to include De Grey, Marble Bar, Nullagine, Telfer and Parnngurr.

Tropical Cyclone Ilsa strengthened to the equivalent of a Category 4 hurricane on Wednesday night. A small circular eye was present at the center of Ilsa’s circulation. The eye was surrounded by a ring of strong 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 Ilsa. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone. The removal of large quantities of mass was causing the surface pressure to continue to decrease.

A weather station at Rowley Shoals measured a sustained wind speed of 95 m.p.h. (83 kt or 154 km/h). The weather station measured a wind gust of 132 m.p.h. (115 kt or 213 km/h). It also measured a sea level pressure of 942.3 mb.

Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Tropical Cyclone Ilsa. Winds to tropical storm force extended out 120 miles (195 km) from the center. The Hurricane Intensity Index (HII) for Tropical Cyclone Ilsa was 25.1. The Hurricane Size Index (HSI) was 13.4 and the Hurricane Wind Intensity Size Index (HWISI) was 38.5. Tropical Cyclone Ilsa was similar in size and intensity to Hurricane Harvey hit Texas in 2017.

Tropical Cyclone Ilsa will move through an environment favorable for intensification during the next 12 hours. Ilsa will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the axis of an upper level ridge that extends from northern Australia to 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 Ilsa could continue to intensify during the next 12 hours.

Tropical Cyclone Ilsa will move around the western end of a high pressure system over western Australia. The high pressure system will steer Ilsa toward the southeast during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Ilsa is likely to make landfall on the coast of Western Australia between Pardoo Roadhouse and Wallal Downs in 12 hours. Ilsa will be the equivalent of a major hurricane when it makes landfall.

Tropical Cyclone Ilsa will bring very strong winds and locally heavy rain to Western Australia between Pardoo Roadhouse and Wallal Downs. The strong winds will be capable of causing regional severe damage. Ilsa could also produce strong winds in De Grey and Telfer when it moves inland. Heavy rain could cause flash floods in some locations. Flood Watches are in effect for the West Kimberley, De Grey River, Sandy Desert, Western Desert, Warburton and Salt Lake Districts. Tropical Cyclone Ilsa could also cause a storm surge of up to 10 to 15 feet (3 to 4.5 meters) along the portion of the coast near where the center makes landfall.

Tropical Cyclone Ilsa Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Ilsa strengthened to the equivalent of a major hurricane over the South Indian Ocean northwest of Australia on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Tropical Cyclone Ilsa was located at latitude 16.8°S and longitude 119.4°E which put it about 200 miles (325 km) west-northwest of Broome, Australia. Ilsa was moving toward the south-southwest at 6 m.p.h. (10 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. (230 km/h). The minimum surface pressure was 956 mb.

A Tropical Cyclone Warning was in effect for the portion of the coast of Western Australia from Bidyadanga to Port Hedland. Tropical Cyclone Watches were in effect for the portions of the coast from Broome to Bidyadanga and from Port Hedland to Whim Creek.

Tropical Cyclone Ilsa strengthened to the equivalent of a major hurricane on Wednesday morning. A small circular eye was present at the center of Ilsa’s circulation. The eye was surrounded by a ring of strong 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 Ilsa. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone. The removal of large quantities of mass was causing the surface pressure to continue to decrease.

The size of the circulation around Tropical Cyclone Ilsa increased, when Ilsa strengthened. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Ilsa’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center. The Hurricane Intensity Index (HII) for Tropical Cyclone Ilsa was 20.6. The Hurricane Size Index (HSI) was 11.5 and the Hurricane Wind Intensity Size Index (HWISI) was 32.1. Tropical Cyclone Ilsa was similar in size and intensity to Hurricane Sally when Sally hit South Alabama in 2020.

Tropical Cyclone Ilsa will move through an environment very favorable for intensification during the next 24 hours. Ilsa will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the axis of an upper level ridge that extends from northern Australia to 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 Ilsa will continue to intensify during the next 24 hours. Ilsa could intensify rapidly at times.

Tropical Cyclone Ilsa will move around the western end of a high pressure system over western Australia. The high pressure system will steer Ilsa toward the south during the next 24 hours. Tropical Cyclone Ilsa will move toward the southeast when it reaches the western end of the high pressure system on Thursday morning. On its anticipated track, Ilsa is likely to make landfall on the coast of Western Australia between Broome and Port Hedland in 30 hours. The center of Tropical Cyclone Ilsa could make landfall near Wallal Downs. Ilsa is likely to be the equivalent of a major hurricane when it makes landfall.

Tropical Cyclone Ilsa will bring very strong winds and locally heavy rain to Western Australia near Wallal Downs. The strong winds will be capable of causing severe damage. Heavy rain could cause flash floods in some locations. Flood Watches are in effect for the West Kimberley, De Grey River, Sandy Desert, Western Desert, Warburton and Salt Lake Districts. Tropical Cyclone Ilsa could also cause a storm surge of up to 10 to 15 feet (3 to 4.5 meters) along the portion of the coast near where the center makes landfall.

Tropical Cyclone Ilsa Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Ilsa rapidly intensified to the equivalent of a hurricane/typhoon on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Tropical Cyclone Ilsa was located at latitude 15.9°S and longitude 120.3°E which put it about 190 miles (305 km) northwest of Broome, Australia. Ilsa was moving toward the southwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (150 km/h). The minimum surface pressure was 975 mb.

A Tropical Cyclone Watch was in effect for the portion of the coast of Western Australia from Beagle Bay to Whim Creek. The Tropical Cyclone Watch included Broome and Port Hedland.

Tropical Cyclone Ilsa intensified rapidly over the South Indian Ocean northwest of Australia on Tuesday. The inner end of a rainband wrapped around the center of Ilsa’s circulation. Other bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated strong upper level divergence that pumped a large quantity of mass away from the tropical cyclone. The removal of a large quantity of mass caused the surface pressure to decrease rapidly, which contributed to the rapid increase in wind speed.

The circulation around Tropical Cyclone Ilsa was small. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Ilsa’s circulation. Winds to tropical storm force extended out 75 miles (120 km) from the center of circulation.

Tropical Cyclone Ilsa will move through an environment very favorable for intensification during the next 24 hours. Ilsa will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the axis of an upper level ridge that extends from northern Australia to 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 Ilsa is likely to continue to intensify rapidly during the next 24 hours. Ilsa could intensify to the equivalent of a major hurricane within 24 hours.

Tropical Cyclone Ilsa will move around the northwestern part of a high pressure system over western Australia. The high pressure system will steer Ilsa toward the southwest during the next 18 hours. Tropical Cyclone Ilsa will move toward the south when it reaches the western end of the ridge on Wednesday. On its anticipated track, Ilsa is likely to make landfall on the coast of Western Australia between Broome and Port Hedland in 48 hours. The center of Tropical Cyclone Ilsa could make landfall near Wallal Downs. Ilsa is likely to be the equivalent of a major hurricane when it makes landfall.

Tropical Cyclone Ilsa Intensifies Rapidly Northwest of Australia

Tropical Cyclone Ilsa intensified rapidly over the South Indian Ocean northwest of Australia on Tuesday morning. At 8:00 a.m. EDT on Tuesday the center of Tropical Cyclone Ilsa was located at latitude 15.2°S and longitude 120.5°E which put it about 225 miles (360 km) north-northwest of Broome, Australia. Ilsa was moving toward the southwest at 11 m.p.h. (17 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 984 mb.

A Tropical Cyclone Watch was in effect for the portion of the coast of Western Australia from Beagle Bay to Whim Creek. The Tropical Cyclone Watch included Broome and Port Hedland.

After moving southwest over the South Indian Ocean for three days without strengthening, a low pressure system previous designated as a tropical low intensified rapidly on Tuesday morning. The Australia Bureau of Meteorology designated the system as Tropical Cyclone Ilsa.

The circulation around Tropical Cyclone Isla was organizing quickly. The inner end of a rainband wrapped around the western side of the center of Ilsa’s circulation. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated more upper level divergence that pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 100 miles (160 km) from the center of Tropical Cyclone Ilsa.

Tropical Cyclone Ilsa will move through an environment very favorable for intensification during the next 24 hours. Ilsa will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the axis of an upper level ridge that extends from northern Australia to 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 Ilsa is likely to continue to intensify rapidly during the next 24 hours. It will strengthen to the equivalent of a hurricane/typhoon. Ilsa could intensify to the equivalent of a major hurricane within 48 hours.

Tropical Cyclone Ilsa will move around the northwest part of a high pressure system over western Australia. The high pressure system will steer Ilsa toward the southwest during the next 24 hours. Tropical Cyclone Ilsa will move toward the south when it reaches the western end of the ridge on Wednesday. On its anticipated track, Ilsa is likely to make landfall on the coast of Western Australia between Broome and Port Hedland within 60 hours. The center of Tropical Cyclone Isla could make landfall near Wallal Downs. Ilsa is likely to be the equivalent of a major hurricane when it makes landfall.