Category Archives: Australian Region

Tropical Cyclone Narelle Intensifies to Equivalent of Cat. 4 Hurricane

Tropical Cyclone Narelle intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Cyclone Narelle was located at latitude 13.6°S and longitude 147.2°E which put the center about 265 miles (425 km) north-northeast of Cairns, Australia.  Narelle was moving toward the west at 17 m.p.h. (28 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 947 mb.

The Australian Bureau of Meteorology issued a Warning for the east coast of the Cape York Peninsula that is in effect from Lockhart River to Cape Tribulation.  The Warning includes Coen and Cooktown.  A Warning is also in effect for the west coast of the Cape York Peninsula from Mapoon to Pormpuraaw.  That Warning includes Weipa.

A Watch is in effect for the portion of the west coast of the Gulf of Carpentaria from south of Nhulunbuy to Port Mcarthur.

A circular eye with a diameter of 12 miles (19 km) was present at the center of Tropical Cyclone Narelle.  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 center of Narelle’s circulation.  Storms near the center of Narelle generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds around Tropical Cyclone Narelle was symmetrical.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Narelle’s circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Tropical Cyclone Narelle.

The Hurricane Intensity Index (HII) for Tropical Cyclone Narelle is 25.1.  The Hurricane Size Index (HSI) is 17.1 and the Hurricane Wind Intensity Size Index (HWISI) is 42.2.  Tropical Cyclone Narelle is similar in intensity to Hurricane Harvey when Harvey hit Texas in 2017.  Narelle is bigger than Harvey was.

Tropical Cyclone Narelle will move through an environment that will be favorable for intensification during the next 12 hours.  Narelle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the northern part of the Coral Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Narelle is likely to intensify during the next 12 hours.

Tropical Cyclone Narelle will move around the northern side of a high pressure system that is over the Coral Sea.   The high pressure system will steer Narelle toward the west during the next 24 hours.   On its anticipated track, Tropical Cyclone Narelle will approach the coast of Queensland near Cape Melville in 12 hours.

Tropical Cyclone Narelle will bring very strong winds and heavy rain to the northern part of the Cape York Peninsula later this week.  Narelle will be capable of causing severe damage.  Heavy rain is likely to cause flash floods in some locations.  Tropical Cyclone Narelle could also cause a storm surge of up to 13 feet (4 meters) along the coast near where the center of circulation makes landfall.

Flood Watches are in effect for parts of the Cape York Peninsula and the North Tropical Coast of Queensland.

Tropical Cyclone Narelle Prompts Warning for Cape York Peninsula

The risks posed by Tropical Cyclone Narelle prompted the Australian Bureau of Meteorology to issue a Warning for part of the Cape York Peninsula on Wednesday.  At 11:00 a.m. EDT on Wednesday the center of Tropical Cyclone Narelle was located at latitude 13.1°S and longitude 149.9°E which put the center about 420 miles (675 km) northeast of Cairns, Australia.  Narelle was moving toward the west-southwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 968 mb.

The Australian Bureau of Meteorology issued a Warning for the coast of Queensland that was in effect from Lockhart River to Cape Tribulation.

A Watch was in effect for the portion of the coast from Weipa to Kowanyama.

Tropical Cyclone Narelle was strengthening as it moved toward the coast of Queensland.

A small circular eye was present at the center of Tropical Cyclone Narelle.  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 center of Narelle’s circulation.  Storms near the center of Narelle 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 Narelle was small. Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Narelle’s circulation.  Winds to  tropical storm force extended out 90 miles (145 km) from the center of Tropical Cyclone Narelle.

The Hurricane Intensity Index (HII) for Tropical Cyclone Narelle was 17.8.  The Hurricane Size Index (HSI) was 11.2 and the Hurricane Wind Intensity Size Index (HWISI) was 29.0.

Tropical Cyclone Narelle will move through an environment that will be favorable for intensification during the next 24 hours.  Narelle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the northern part of the Coral Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Narelle will intensify during the next 24 hours.  Narelle could intensify rapidly at times.  Tropical Cyclone Narelle could strengthen to the equivalent of a major hurricane by Thursday.

Tropical Cyclone Narelle will move around the northern side of a high pressure system that is over the Coral Sea.   The high pressure system will steer Narelle toward the west during the next 24 hours.   On its anticipated track, Tropical Cyclone Narelle will approach the coast of Queensland near Cape Melville in 24 hours.

Tropical Cyclone Narelle will bring strong winds and heavy rain to the northern part of the Cape York Peninsula later this week.  Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for parts of the Cape York Peninsula and the North Tropical Coast of Queensland.

Tropical Cyclone Narelle Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Narelle strengthened to the equivalent of a hurricane/typhoon as it moved over the Coral Sea on Tuesday evening.  At 8:00 p.m. EDT on Tuesday the center of Tropical Cyclone Narelle was located at latitude 12.4°S and longitude 153.3°E which put the center about 600 miles (970 km) east-northeast of Cairns, Australia.  Narelle was moving toward the west at 10 m.p.h. (16 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 986 mb.

The Australian Bureau of Meteorology issued a Watch that was in effect for the portion of the coast of Queensland from Lockhart River to Port Douglas.  The Watch extended across the central Cape York Peninsula to the Gulf of Carpentaria.  The Watch was in effect for the west coast of the Cape York Peninsula from Weipa to Kowanyama.

Tropical Cyclone Narelle intensified to the equivalent of a hurricane/typhoon on Tuesday evening.  The inner end of a rainband wrapped around the center of Narelle’s circulation.  A small eye formed at the center of Tropical Cyclone Narelle.  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 center of Narelle’s circulation.  Storms near the center of Narelle 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 Narelle was small.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Narelle’s circulation.

Tropical Cyclone Narelle will move through an environment that will be favorable for intensification during the next 24 hours.  Narelle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the northern part of the Coral Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Narelle will intensify during the next 24 hours.  Narelle could intensify rapidly at times.  Tropical Cyclone Narelle could strengthen to the equivalent of a major hurricane by Thursday.

Tropical Cyclone Narelle will move around the northern side of a high pressure system that is over the Coral Sea.   The high pressure system will steer Narelle toward the west during the next 24 hours.   On its anticipated track, Tropical Cyclone Narelle will approach the coast of Queensland near Cape Melville in 35 hours.

Tropical Cyclone Narelle will bring strong winds and heavy rain to the northern part of the Cape York Peninsula later this week.  Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for parts of the Cape York Peninsula and the North Tropical Coast of Queensland.

Tropical Cyclone Narelle Develops Over the Coral Sea

Tropical Cyclone Narelle developed over the Coral Sea on Monday night.  At 11:00 a.m. EDT on Tuesday the center of Tropical Cyclone Narelle was located at latitude 12.4°S and longitude 154.8°E which put the center about 705 miles (1140 km) east-northeast of Cairns, Australia.  Narelle was moving toward the west 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 987 mb.

A low pressure system over the Coral Sea strengthened on Monday night and the Australian Bureau of Meteorology designated the system as Tropical Cyclone Narelle.

The Australian Bureau of Meteorology issued a Watch for the coast of Queensland from Lockhart River to Port Douglas.

Tropical Cyclone Narelle was intensifying rapidly on Tuesday morning.  The inner end of a rainband wrapped around the center of Narelle’s circulation.  A small eye appeared to be forming at the center of Tropical Cyclone Narelle.  Bands of showers and thunderstorms were revolving around the center of Narelle’s circulation.  Storms near the center of Narelle 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 Narelle was small.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Narelle’s circulation.

Tropical Cyclone Narelle will move through an environment that will be favorable for intensification during the next 24 hours.  Narelle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the northern part of the Coral Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Narelle will intensify during the next 24 hours.  Narelle could intensify rapidly.  Tropical Cyclone Narelle will strengthen to the equivalent of a hurricane/typhoon during the next few hours.  Narelle could intensify to the equivalent of a major hurricane by Thursday.

Tropical Cyclone Narelle will move around the northern side of a high pressure system that is over the Coral Sea.  The high pressure system will steer Narelle toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Narelle will approach the coast of Queensland near Cape Melville in 48 hours.

Tropical Cyclone Narelle will bring strong winds and heavy rain to the northern part of the Cape York Peninsula later this week.  Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for parts of the Cape York Peninsula and the North Tropical Coast of Queensland.

Tropical Cyclone 24P Forms over the Coral Sea

Tropical Cyclone 24P formed over the Coral Sea on Tuesday night.  At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone 24P was located at latitude 14.3°S and longitude 150.6°E which put the center about 380 miles (615 km) east-northeast of Cairns, Australia.  Tropical Cyclone 24P was moving toward the south-southeast at 3 m.p.h. (5 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 996 mb.

The Australian Bureau of Meteorology issued a Watch for the portion of the coast from Cooktown to Lucinda.  The Watch included Port Douglas, Cairns, Innisfail and Palm Island.

A low pressure system over the Coral Sea strengthened on Tuesday night and the U.S. Joint Typhoon Warning Center designated the system as Tropical Cyclone 24P.  The Australian Bureau of Meteorology was designating the system as Tropical Low 29U.

The distribution of thunderstorms in Tropical Cyclone 24P was asymmetrical.  Thunderstorms were occurring in bands in the western half of the tropical cyclone’s circulation.  Bands in the eastern side of the circulation consisted primarily of showers and lower clouds.  Storms near the center of Tropical Cyclone 24P began to generate upper level divergence that pumped mass away to the west of the tropical cyclone.

Winds to tropical storm force extended out 100 miles (160 km) from the center of Tropical Cyclone 24P.

Tropical Cyclone 24P will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  The tropical cyclone will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the northern part of an upper level ridge that extended from the Coral Sea to over Australia.  The upper level ridge will produce easterly winds that will blow toward the top of the tropical cyclone’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will not be enough to prevent intensification.  Tropical Cyclone 24P will intensify during the next 24 hours.

Tropical Cyclone 24 P will move around the northwestern part of a high pressure system that is over the Coral Sea.  The high pressure system will steer the tropical cyclone during the next 24 hours.  On its anticipated track, Tropical Cyclone 24P will approach the coast of Queensland near Cairns in two days.

Tropical Cyclone 24P will bring strong winds and locally heavy rain to the coast of Queensland near Cairns.  Heavy rain could cause flooding in some locations.

Flood Watches are in effect for the parts of the Cape York Peninsula, the Central Coast, Capricornia, and Carpentaria catchments.

Tropical Cyclone Mitchell Moves Over Western Australia

Tropical Cyclone Mitchell moved over the coast of Western Australia south of Carnarvon on Monday.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Mitchell was located at latitude 25.8°S and longitude 114.2°E which put the center about 70 miles (110 km) south-southeast of Carnarvon, Australia.  Mitchell was moving toward the south-southeast at 11 m.p.h. (17 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 991 mb.

The Australian Bureau of Meteorology issued a Warning that was in effect for the portion of the coast from Carnarvon to Overlander Roadhouse.  The Warning included Denham.

Tropical Cyclone Mitchell was the equivalent of a tropical storm at the time it moved over the coast of Western Australia.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Mitchell’s circulation.

A weather station in Carnarvon, Australia measured a sustained wind speed of 43 m.p.h. (69 km/h) and a wind gust of 63 m.p.h. (102 km/h).

Tropical Cyclone Mitchell will move around the southwestern part of a high pressure system that is over Australia.  The high pressure system will steer Mitchell toward the south-southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Mitchell will move inland over Western Australia.  The center of Mitchell’s circulation will pass east of Denham.

Tropical Cyclone Mitchell will bring gusty winds and locally heavy rain to the area between Denham and Overlander Roadhouse during the next few hours.  Heavy rain could cause floods in some locations.

Flood Watches are in effect for the Gascoyne River, the Avon River, the Moore River, the Hill River, the Greenough River, the Murchison River, the Wooramel River, the Linden-Minilya Rivers, and the Yarra Yarra Lakes District.

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 Low Prompts Warning for Western Australia

The potential risk posed by a Tropical Low prompted the Australia Bureau of Meteorology to issue a Warning for a portion of the coast of Western Australia on Thursday.  At 10:00 p.m. EST on Thursday the center of a Tropical Low was located at latitude 17.9°S and longitude 121.5°E which put the center about 25 miles (40 km) west-northwest of Broome, Australia.  The Tropical Low was moving toward the west at 8 m.p.h. (13 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 997 mb.

The Australian Bureau of Meteorology issued a Warning for the portion of the coast of Western Australia from Pardoo Roadhouse to Whim Creek.  The Warning included Port Hedland.

The Australian Bureau of Meteorology issued a Watch for the portion of the coast of Western Australia from Whim Creek to Exmouth Gulf.  The Watch included Karratha,Dampier, and Onslow.

A low pressure system strengthened on Thursday when it moved over the South Indian Ocean near Broome, Australia.  The Australian Bureau of Meteorology designated the system as a Tropical Low.  The U.S. Joint Typhoon Warning Center designated the system as Tropical Cyclone 20S.

The Tropical Low started to strengthen on Thursday as soon as it moved over the water in the South Indian Ocean.  More thunderstorms formed near the center of the Tropical Low.  Thunderstorms also developed in bands revolving around the center of circulation.  Storms near the center began to generate upper level divergence that pumped mass away from the Tropical Low.  The removal of mass caused the surface pressure to start to decrease.

The Tropical Low will move through an environment very favorable for intensification during the next 24 hours.  The Tropical Low 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.  The Tropical Low will intensify during the next 24 hours.  It could intensify rapidly to the equivalent of a hurricane/typhoon.

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

The center of the Tropical Low is likely to stay north of the coast of Western Australia on Friday.  Bands in the southern half of the Tropical Low could bring gusty winds and locally heavy rain to portions of the coast.