Tag Archives: Pilbara

Tropical Cyclone Mitchell Passes Near Exmouth

Tropical Cyclone Mitchell was passing near Exmouth in Western Australia on Sunday morning.  At 10:00 a.m. EST on Sunday the center of Tropical Cyclone Mitchell was located at latitude 22.0°S and longitude 113.8°E which put the center about 25 miles (40 km) north-northwest of Exmouth, Australia.  Mitchell was moving toward the west-southwest at 9 m.p.h. (15 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 983 mb.

The Australian Bureau of Meteorology issued a Warning that was in effect for the portion of the coast from Onslow to Overlander Roadhouse.  The Warning included Exmouth, Carnarvon, and Denham.  The Warning extended inland to include Gascoyne Junction.

Even though the center of Tropical Cyclone Mitchell remained offshore, Mitchell was producing strong winds along the coast of Western Australia.  A weather station at the Onslow airport measured a sustained wind speed of 59 m.p.h. (95 km/h) and a wind gust of 75 m.p.h. (120 km/h).

Tropical Cyclone Mitchell weakened on Saturday night even though the center of Mitchell remained over water.  Southeasterly winds blowing into the southwestern part of Mitchell’s circulation appeared to pull drier air from the interior of Western Australia into the western side of the circulation.  The drier air caused many of the thunderstorms in the southwestern part of Tropical Cyclone Mitchell to weaken.  Thunderstorms were still occurring in bands in the other parts of Mitchell’s circulation.  Since there were fewer thunderstorms near the center of Mitchell, those thunderstorms generated less upper level divergence.  Less upper level divergence meant that the thunderstorms pumped less mass away from the tropical cyclone.  The removal of less mass caused the surface pressure to increase.

The circulation around Tropical Cyclone Mitchell continued to be small.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Mitchell’s circulation.

Tropical Cyclone Mitchell will move through an environment that will be unfavorable for intensification during the next 24 hours.  Mitchell will move over water where the Sea Surface Temperatures are near 29°C.  However, it will move under the western end of an upper level ridge that is over Australia.  The upper level ridge will produce northwesterly winds that will blow toward the top of Mitchell’s circulation.  Those winds will cause the vertical wind shear to increase.  In addition, Tropical Cyclone Mitchell is likely to continue to pull drier air into its circulation.  The combination of more vertical wind shear and drier air will cause Tropical Cyclone Mitchell to weaken slowly during the next 24 hours.

Tropical Cyclone Mitchell will move around the western end of a high pressure system that is over Australia.  The high pressure system will steer Mitchell toward the south during the next 24 hours.  On its anticipated track, the center of Tropical Cyclone Mitchell will make landfall on the coast of Western Australia near Cape Cuvier and Carnarvon in 12 hours.

Tropical Cyclone Mitchell will bring strong winds and heavy rain parts of Western Australia near Cape Cuvier and Carnarvon.  Heavy rain is likely to cause floods in some locations.

Flood Watches are in effect for the Gascoyne River, the Ashburton River, the Fortescue River, the Greenough River, the Murchison River, the Wooramel River, the Pilbara Coastal Rivers, and the Yarra Yarra Lakes District.

Tropical Cyclone Mitchell Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Mitchell intensified to the equivalent of a hurricane/typhoon as it moved near the coast of Western Australia on Saturday morning.  At 10:00 a.m. EST on Saturday the center of Tropical Cyclone Mitchell was located at latitude 20.3°S and longitude 116.4°E which put the center about 50 miles (80 km) north-northwest of Karratha, Australia.  Mitchell was moving toward the southwest at 12 m.p.h. (19 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 973 mb.

The Australian Bureau of Meteorology issued a Warning that was in effect for the portion of the coast of Western Australia from Whim Creek to Coral Bay.  The Warning included Karratha, Dampier, Onslow, and Exmouth.

A Watch was in effect for the portion of the coast of Western Australia from Coral Bay to Carnarvon.

Tropical Cyclone Mitchell intensified to the equivalent of a hurricane/typhoon on Saturday morning.  The inner end of a rainband wrapped around the center of Michell’s circulation.  An eye appeared to be forming at the center of Tropical Cyclone Mitchell.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Mitchell’s circulation.  Storms near the center of Mitchell 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 Mitchell increased when Mitchell intensified.  Winds to hurricane/typhoon force extended out 40 miles (65 km) from the center of Mitchell’s circulation.  Winds to tropical storm force extended out 100 miles (175 km) from the center of Tropical Cyclone Mitchell.

Tropical Cyclone Mitchell will move through an environment very favorable for intensification during the next 24 hours.  Mitchell will then move over water where the Sea Surface Temperatures are near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Mitchell will intensify during the next 24 hours. .

Tropical Cyclone Mitchell will move around the northwestern part of a high pressure system that is over Australia.  The high pressure system will steer Mitchell toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Mitchell will make landfall in the Exmouth Gulf in less than 24 hours.

The center of Tropical Cyclone Mitchell is likely to make landfall on the coast of Western Australia between Onslow and Exmouth.  Mitchell will bring strong winds and heavy rain to locations near the Exmouth Gulf.  Heavy rain is likely to cause floods in some locations.

Flood Watches are in effect for the Gascoyne River, the Ashburton River, the Fortescue River, the Fitzroy River, the Greenough River, the Murchison River, the Wooramel River, the Pilbara Coastal Rivers, and the Yarra Yarra Lakes District.

Tropical Cyclone Mitchell Strengthens Near Western Australia

Tropical Cyclone Mitchell strengthened near the coast of Western Australia on Friday morning.  At 10:00 a.m. EST on Friday the center of Tropical Cyclone Mitchell was located at latitude 18.7°S and longitude 119.4°E which put the center about 145 miles (235 km) north-northeast of Port Hedland, Australia.  Mitchell was moving toward the west-southwest at 12 m.p.h. (19 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 994 mb.

The Australian Bureau of Meteorology issued a Warning that was in effect for the portion of the coast from De Grey to Mardie.  The Warning included Port Hedland, Karratha, and Dampier.

A Watch was in effect for the portion of the coast from Onslow to Coral Bay.  The Watch included Exmouth.

A Tropical Low near the coast of Western Australia strengthened on Friday morning and the Australian Bureau of Meteorology designated it as Tropical Cyclone Mitchell.

The circulation around Tropical Cyclone Mitchell was strengthening on Friday morning.  New thunderstorms continued to develop near the center of Mitchell’s circulation.  Bands of showers and thunderstorms were also revolving around the center of Tropical Cyclone Mitchell.  Storms near the center of Mitchell 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 Mitchell was small.  Winds to tropical storm force extended out 65 miles (105 km) from the center of Mitchell’s circulation.

Tropical Cyclone Mitchell will move through an environment very favorable for intensification during the next 24 hours.  Mitchell will then move over water where the Sea Surface Temperatures are near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Mitchell will intensify during the next 24 hours.  Mitchell could intensify rapidly to the equivalent of a hurricane/typhoon.

Tropical Cyclone Mitchell will move around the northwestern part of a high pressure system that is over Australia.  The high pressure system will steer Mitchell toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone will be north of Dampier in 24 hours.

The strongest winds in Tropical Cyclone Mitchell will remain north of the coast of Western Australia on Friday.  Bands in the southern half of Mitchell’s circulation could bring strong winds and locally heavy rain to the coast of Western Australia.  Heavy rain could cause flash floods in some locations.

Flood Watches are in effect for the Gascoyne River, the Ashburton River, the Fortescue River, the Fitzroy River, and the Pilbara Coastal Rivers.

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.

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 Rapidly Intensifies to Equivalent of Major Hurricane

Tropical Cyclone Zelia rapidly intensified to the equivalent of a major hurricane near the coast of Western Australia on Wednesday.  At 10:00 p.m. EST on Wednesday the center of Tropical Cyclone Zelia was located at latitude 19.1°S and longitude 118.1°E which put the center about 80 miles (130 km) north-northwest of Port Hedland, Australia.  Zelia was nearly stationary.  The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (265 km/h).  The minimum surface pressure was 940 mb.

Tropical Cyclone Zelia rapidly intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Thursday.  A small circular eye with a diameter of 12 miles (19 km) formed at the center of Zelia’s circulation.  A ring of thunderstorms surrounded the center of Zelia and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Zelia.  Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone.  The removal of large amounts of mass caused the surface pressure to decrease rapidly.

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 115 miles (185 km) from the center of Tropical Cyclone Zelia.

The Hurricane Intensity Index (HII) for Tropical Cyclone Zelia was 28.3.  The Hurricane Size Index (HSI) was 14.1 and the Hurricane Wind Intensity Size Index (HWISI) was 42.4.

Tropical Cyclone Zelia will move through an environment favorable for intensification during the next 24 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.  Tropical Cyclone Zelia will continue to intensify during the next 24 hours.  Zelia could intensify rapidly at times.  Tropical Cyclone Zelis could strengthen to the equivalent of Category 5 hurricane on the Saffir-Simpson Scale.

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 southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone will move closer to the coast of Western Australia.  Zelia could approach the coast between Port Hedland and Dampier in 36 hours.

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

A Warning is in effect for the portion of the coast from Bidyadanga to Dampier.  The Warning includes Port Hedland, Karratha, De Grey, and Wallal Downs.  The Warning extends inland to Marble Bar.

A Watch is in effect for the portion of the coast from Dampier to Mardie.  The Watch extends inland to Nullagine and Tom Price.

Heavy rain is likely to cause floods in some locations.

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

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

Tropical Cyclone Zelia Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Zelia intensified to the equivalent of a hurricane/typhoon near the coast of Western Australia early on Wednesday.  At 4:00 a.m. EST on Wednesday the center of Tropical Cyclone Zelia was located at latitude 19.1°S and longitude 118.6°E which put the center about 80 miles (130 km) north of Port Hedland, Australia.  Zelia was moving toward the south-southwest at 3 m.p.h. (5 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 978 mb.

Tropical Cyclone Zelia exhibited signs of rapid intensification early on Wednesday.  The inner end of a rainband wrapped around the center of Zelia’s circulation.  A small eye appeared to be forming at the center of Tropical Cyclone Zelia.  A ring of thunderstorms surrounded the center of Zelia and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Zelia.  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 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 115 miles (185 km) from the center of Tropical Cyclone Zelia.

Tropical Cyclone Zelia will move through an environment favorable for intensification during the next 24 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.  Tropical Cyclone Zelia will intensify during the next 24 hours.  Zelia could intensify rapidly at times.  Tropical Cyclone Zelis could strengthen to the equivalent of a major hurricane.

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 west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone will move closer to the coast of Western Australia. Zelia could approach the coast between De Grey and Dampier in 36 hours.

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

A Warning is in effect for the portion of the coast from Bidyadanga to Dampier.  The Warning includes Port Hedland, Karratha, De Grey, and Wallal Downs.  The Warning extends inland to Marble Bar.

A Watch is in effect for the portion of the coast from Dampier to Mardie.  The Warning extends inland to Nullagine.

Heavy rain is likely to cause floods in some locations.

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

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

Elsewhere over the South Indian Ocean, Tropical Cyclone Vince made a transition to an extratropical cyclone and Tropical Cyclone Taliah continued to move farther away from the Cocos Islands.

At 4:00 a.m. EST on Wednesday the center of Tropical Cyclone Taliah was located at latitude 18.2°S and longitude 90.3°E which put the center about 565 miles (915 km) south-southwest of the Cocos Islands.  Taliah was moving toward the southwest at 15 m.p.h. (24 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 Low Strengthens to Tropical Cyclone Zelia

A former Tropical Low near the coast of Western Australia strengthened to Tropical Cyclone Zelia on Tuesday.  At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone Zelia was located at latitude 18.7°S and longitude 118.9°E which put the center about 110 miles (175 km) north of Port Hedland, Australia.  Zelia was moving toward the south-southwest at 7 m.p.h. (11 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 991 mb.

A former Tropical Low near the coast of Western Australia strengthened on Tuesday and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Zelia.  More thunderstorms formed near the center of Zelia’s circulation.  Bands of showers and thunderstorms were revolving around 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 caused the surface pressure to decrease.

The circulation around Tropical Cyclone Zelia became more symmetrical on Tuesday.  Winds to tropical storm force extended out 145 miles (230 km) from the center of Zelia’s circulation.

A weather station on Rowley Shoals measured a sustained wind speed of 47 kt (54 m.p.h. or 87 km/h) and a wind gust of 64 kt (74 m.p.h. or 119 km/h).

Tropical Cyclone Zelia will move through an environment favorable for intensification during the next 24 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.  Tropical Cyclone Zelia will intensify during the next 24 hours.  Zelia is likely to strengthen to the equivalent of a hurricane/typhoon.

Tropical Cyclone Zelia will move around the western 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, Tropical Cyclone will move closer to the coast of Western Australia.  Zelia could approach the coast between Wallal Downs and Port Hedland in 48 hours.

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

A Warning is in effect for the portion of the coast from Broome to Port Hedland.  The Warning includes Wallal Downs and De Grey.

A Watch is in effect for the portion of the coast from Port Hedland to Dampier.  The Watch extends inland to Marble Bar.

Heavy rain is likely to cause floods in some locations.

Flood Watches are in effect for the De Grey River, the Pilbara coastal Rivers, the Fortescue River and parts of the Sandy Desert.

Elsewhere over the South Indian Ocean, Tropical Cyclone Vince continued to move farther away from Rodrigues and Tropical Cyclone Taliah continued to move farther away from the Cocos Islands.

At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone Vince was located at latitude 29.5°S and longitude 70.3°E which put the center about 805 miles (1295 km) south-southeast of Port Mathurin, Rodrigues.  Vince was moving toward the south-southeast at 12 m.p.h. (19 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). vThe minimum surface pressure was 971 mb.

At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone Taliah was located at latitude 16.4°S and longitude 91.5°E which put the center about 435 miles (705 km) southwest of the Cocos Islands.  Taliah was moving toward the south-southwest at 8 m.p.h. (13 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 982 mb.

Tropical Cyclone Sean Rapidly Intensifies to Equivalent of Major Hurricane

Tropical Cyclone Sean rapidly intensified to the equivalent of a major hurricane over the South Indian Ocean west of Australia on Monday.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Sean was located at latitude 23.0°S and longitude 110.4°E which put the center about 210 miles (340 km) west of Exmouth, Australia.  Sean was moving toward the southwest at 13 m.p.h. (21 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 936 mb.

A Warning was in effect for the portion of the coast from Onslow to Ningaloo.  The Warning included Exmouth.

Tropical Cyclone Sean rapidly intensified to the equivalent of a major hurricane west of Australia on Monday.  A small circular eye with a diameter of 10 miles (16 km) was at the center of Sean’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 Sean.  Storms near the core of Sean generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone.  The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The circulation around Tropical Cyclone Sean was relatively small.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Sean’s circulation.  Winds to tropical storm force extended out 110 miles (175 km) from the center of Tropical Cyclone Sean.

The Hurricane Intensity Index (HII) for Tropical Cyclone Sean was 25.1.  The Hurricane Size Index (HSI) was 12.6 and the Hurricane Wind Intensity Size Index (HWISI) was 37.7.  Tropical Cyclone Sean was similar in size and intensity to Hurricane Harvey when Harvey hit Texas in 2017.

Tropical Cyclone Sean will move through an environment that will become unfavorable for intensification during the next 24 hours.  Sean will move over water where where the Sea Surface Temperatures are near 27°C.  It will move under the eastern part of an upper level trough over the South Indian Ocean.  The upper level trough will produce northwesterly winds are that will blow toward the top of Sean’s circulation.  Those winds will cause the vertical wind shear to increase.  The combination of cooler water and  more vertical wind shear will cause Tropical Cyclone Sean to weaken during the next 24 hours.

Tropical Cyclone Sean will move around the northwestern part of a high pressure system over Australia.  The high pressure system will steer Sean toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Sean will move a little farther away from the coast of Western Australia.

Bands in the eastern side of Tropical Cyclone Sea will bring gusty winds and locally heavy rain to the coast of Western Australia.  Heavy rain could cause floods in some locations.  10.78 inches (274 mm) of rain has already fallen at the Karratha Airport.  4.37 inches (111 mm) of rain has already fallen at the Mardie Airport.

Flood Warnings were in effect for parts of the Pilbara and northern Gascoyne regions.  A Flood Warning was in effect for the Lyndon-Minilya Rivers. 

 

Tropical Cyclone Sean Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Sean intensified to the equivalent of a hurricane/typhoon near the coast of Western Australia on Sunday.  At 10:00 a.m. EST on Sunday the center of Tropical Cyclone Sean was located at latitude 20.5°S and longitude 113.9°E which put the center about 125 miles (200 km) north of Exmouth, Australia.   Sean was moving toward the west-southwest at 12 m.p.h. (19 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 978 mb.

A Warning was in effect for the portion of the coast from Whim Creek to Ningaloo.  The Warning included Karratha, Damoier, Onslow, and Exmouth.

Tropical Cyclone Sea intensified to the equivalent of a hurricane/typhoon near the coast of Western Australia on Sunday.  A circular eye with a diameter of 17 miles (28 km) formed at the center of Sean’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 Sean.  Storms near the core of Sean 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 Sean was relatively small.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Sean’s circulation.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Tropical Cyclone Sean.

Tropical Cyclone Sean will move through an environment favorable for intensification during the next 24 hours.  Sean will move over water where where the Sea Surface Temperatures are near 30°C.  It will move under the northern part of an upper level ridge northwest of Australia.  The upper level ridge will produce easterly winds are that will blow toward the top of Sean’s circulation.  Those winds will cause some vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Cyclone Sean will intensify during the next 24 hours.

Tropical Cyclone Sean will move around the northwestern part of a high pressure system over Australia.  The high pressure system will steer Sean toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Sean will move parallel to the coast of Western Australia.  The center of Sean is forecast to remain over water.

Bands in the southern side of Tropical Cyclone Sea will bring gusty winds and locally heavy rain to the coast of Western Australia.  Heavy rain could cause flash floods in some locations.  3.74 inches (95 mm) of rain fell at the Lombadina Airstrip.

A Flood Watch was in effect for the coastal parts of the Kimberley and the Pilbara Districts.  Catchments likely to be affected include the West Kimberley Rivers, the De Grey River, the Pilbara Coastal Rivers, the Fortescue River, the Onslow Coast, and the Lyndon-Minilya Rivers.