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Tropical Cyclone Gezani Clips Mozambique

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The western side of Tropical Cyclone Gezani clipped the coast of Mozambique near Inhambane on Friday night.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Gezani was located at latitude 24.4°S and longitude 35.8°E which put the center about 35 miles (55 km) southeast of Inhambane, Mozambique.  Gezani was moving toward the south-southwest at 11 m.p.h. (17 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 960 mb.

Tropical Cyclone Gezani was the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale when it clipped the coast of Mozambique on Friday night.  A circular eye with a diameter of 20 miles (32 km) was present at the center of Gezani’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 center of Gezani’s circulation.  Storms near the center of Gezani 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 Gezani was small.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Gezani’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Tropical Cyclone Gezani.

The Hurricane Intensity Index (HII) for Tropical Cyclone Gezani was 19.2.  The Hurricane Size Index (HSI) was 12.9 and the Hurricane Wind Intensity Size Index (HWISI) was 32.1.  Tropical Cyclone Gezani was similar in size and intensity to Hurricane Sally when Sally hit Alabama in 2020.

Tropical Cyclone Gezani will move through an environment that will become less favorable for intensification during the next 24 hours.  Gezani will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the eastern side of an upper level trough that is over South Africa.  The upper level trough will produce northwesterly winds that will blow toward the top of Gezani’s circulation.  Those winds will cause the vertical wind shear to increase.  Tropical Cyclone Gezani is likely to maintain its intensity during the next 24 hours.

The upper level trough will start to steer Tropical Cyclone Gezani toward the south-southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Gezani will start to move away from the coast of central Mozambique on Saturday.

Bands in the western half of Tropical Cyclone Gezani circulation will continue to bring strong winds and locally heavy rain to the region near Inhambane during the next few hours.  Heavy rain could cause flash floods in some locations.

Tropical Cyclone Gezani Nears Mozambique

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Tropical Cyclone Gezani was nearing the coast of Mozambique on Friday morning.  At 10:00 a.m. EST on Friday the center of Tropical Cyclone Gezani was located at latitude 22.8°S and longitude 36.3°E which put the center about 130 miles (210 km) north-northeast of Inhambane, Mozambique.  Gezani was moving toward the southwest at 9 m.p.h. (15 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 964 mb.

Tropical Cyclone Gezani was strengthening on Friday morning as it neared the coast of Mozambique.  A circular eye with a diameter of 25 miles (40 km) was present at the center of Gezani’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 center of Gezani’s circulation.  Storms near the center of Gezani 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 Gezani increased a little when Gezani strengthened.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Gezani’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Tropical Cyclone Gezani.

The Hurricane Intensity Index (HII) for Tropical Cyclone Gezani was 17.8.  The Hurricane Size Index (HSI) was 14.1 and the Hurricane Wind Intensity Size Index (HWISI) was 31.9.  Tropical Cyclone Gezani was similar in size and intensity to Hurricane Sally when Sally hit Alabama in 2020.

Tropical Cyclone Gezani will move through an environment that will be favorable for intensification during the next 24 hours.  Gezani 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 Mozambique Channel.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Gezani is likely to intensify during the next 24 hours.  Gezani could strengthen to the equivalent of a major hurricane on Friday.

Tropical Cyclone Gezani will move around the western side of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Gezani toward the south during the next 24 hours.  On its anticipated track, the center of Tropical Cyclone Gezani will pass very close to the coast of central Mozambique during the next 24 hours.

The center of Tropical Cyclone Gezani is currently forecast to pass just to the east of the coast of central Mozambique.  Bands in the western half of Gezani’s circulation could bring strong winds and locally heavy rain to the region near Inhambane.  Heavy rain could cause flash floods in some locations.  If Tropical Cyclone Gezani moves a little to the west of the forecast track, then the strongest part of Gezani’s circulation could hit the area around Inhambane.

Tropical Cyclone Gezani Intensifies to Equivalent of Major Hurricane

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Tropical Cyclone Gezani intensified to the equivalent of a major hurricane east of Madagascar on Tuesday morning.  At 10:00 a.m. EST on Tuesday the center of Tropical Cyclone Gezani was located at latitude 18.1°S and longitude 49.5°E which put the center about 105 miles (165 km) east of Toamasina, Madagascar.  Gezani was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 956 mb.

Tropical Cyclone Gezani rapidly intensified to the equivalent of a major hurricane east of Toamasina, Madagascar on Tuesday morning.  A small circular eye with a diameter of 20 miles (32 km) was at the center of Tropical Cyclone Gezani.  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 Gezani’s circulation.  Storms near the center of Gezani 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 small circulation around Tropical Cyclone Gezani was very symmetrical.  Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Gezani’s circulation.   Winds to tropical storm force extended out 80 miles (130 km) from the center of Tropical Cyclone Gezani.

The Hurricane Intensity Index (HII) for Tropical Cyclone Gezani is 23.6. The Hurricane Size Index (HSI) is 11.0 and the Hurricane Wind Intensity Size Index (HWISI) is 34.6. Tropical Cyclone Gezani is similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

Tropical Cyclone Gezani will move through an environment that will be very favorable for intensification during the next few hours.  Gezani will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the middle of an upper level ridge that is 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 Gezani could continue to intensify during the next few hours.

Tropical Cyclone Gezani will move around the northern side of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Gezani toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Gezani will reach the east coast of Madagascar near Toamasina in a few hours.

Tropical Cyclone Gezani will be the equivalent of a major hurricane when it hits the east coast of Madagascar.  Gezani will bring strong winds and locally heavy rain to central Madagascar. Heavy rain will cause flash floods in some locations.  Tropical Cyclone Gezani will be capable of causing major damage to central Madagascar.  Widespread outages of electricity are likely.  Tropical Cyclone Gezani could also cause a storm surge of up to 13 feet (4 meters) along parts of the east coast of Madagascar near Toamasina.

Tropical Cyclone Gezani Rapidly Intensifies to Equivalent of Cat. 2 Hurricane

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Tropical Cyclone Gezani rapidly intensified to the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale east of Madagascar on Monday.  At 10:00 p.m. EST on Monday the center of Tropical Cyclone Gezani was located at latitude 18.2°S and longitude 51.6°E which put the center about 245 miles (395 km) east of Toamasina, Madagascar.  Gezani was moving toward the west at 9 m.p.h. (15 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 973 mb.

Tropical Cyclone Gezani rapidly intensified to the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale on Monday.  The inner end of a rainband wrapped around the center of Gezani’s circulation.  A circular eye with a diameter of 20 miles (32 km) formed at the center of Tropical Cyclone Gezani.  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 Gezani’s circulation.  Storms near the center of Gezani 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 Gezani was small.  Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Gezani’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Tropical Cyclone Gezani.

The Hurricane Intensity Index (HII) for Tropical Cyclone Gezani is 17.8.  The Hurricane Size Index (HSI) is 9.8 and the Hurricane Wind Intensity Size Index (HWISI) is 27.6.  Tropical Cyclone Gezani is similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Tropical Cyclone Gezani will move through an environment that will be very favorable for intensification during the next 12 hours.  Gezani will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the middle of an upper level ridge that is 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 Gezani will intensify during the next 12 hours. Gezani could continue to intensify rapidly.  Tropical Cyclone Gezani could strengthen to the equivalent of a major hurricane.

Tropical Cyclone Gezani will move around the northern side of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Gezani toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Gezani will reach the east coast of Madagascar near Toamasina in 12 hours.

Tropical Cyclone Gezani is likely to be the equivalent of a major hurricane when it hits the east coast of Madagascar.  Gezani will bring strong winds and locally heavy rain to central Madagascar.  Heavy rain will cause flash floods in some locations. Tropical Cyclone Gezani will be capable of causing major damage to central Madagascar.  Tropical Cyclone Gezani could also cause a storm surge of up to 13 feet (4 meters) along parts of the east coast of Madagascar near Toamasina.

Tropical Cyclone Fytia Rapidly Intensifies to Equivalent of a Major Hurricane

Tropical Cyclone Fytia rapidly intensified to the equivalent of a major hurricane before it hit the west coast of Madagascar on Friday night.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Fytia was located at latitude 16.3°S and longitude 45.2°E which put the center about 25 miles (40 km) west of Soalala, Madagascar.  Fytia was moving toward the east-southeast at 12 m.p.h. (19 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 Fytia continued to intensify rapidly on Friday right up to the time it hit the west coast of Madagascar.  A small circular eye was at the center of Tropical Cyclone Fytia.  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 Fytia’s circulation.  Storms near the core of Fytia 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 Fytia was small.  Winds to tropical storm force extended out 25 miles (40 km) from the center of Fytia’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Tropical Cyclone Fytia.

The Hurricane Intensity Index (HII) for Tropical Cyclone Fytia was 20.6. The Hurricane Size Index (HWISI) was 9.4 and the Hurricane Wind Intensity Size Index (HWISI) was 30.0 Tropical Cyclone Fytia was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Tropical Cyclone Fytia will move around the southwestern part of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Fytia toward the southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Fytia will across central Madagascar on Saturday.

The center of Tropical Cyclone Fytia made landfall on the west coast of Madagascar west of Soalala.  The center of Fytia’s circulation is likely to pass between Antananarivo and Toamasina on Saturday night.  Tropical Cyclone Fytia will weaken as it moves across Madagascar.

Tropical Cyclone Fytia will bring strong winds and locally heavy rain to the coast of west central Madagascar and to central Madagascar.  Fytia could cause major damage in those areas.   Heavy rain is very likely to cause flash floods in some locations. Tropical Cyclone Fytia could also cause a storm surge of up to 10 feet (3 meters) along parts of the west coast of Madagascar.

Tropical Cyclone Fytia Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Fytia rapidly intensified to the equivalent of a hurricane/typhoon over the Mozambique Channel early on Friday.  At 10:00 a.m. EST on Friday the center of Tropical Cyclone Fytia was located at latitude 15.5°S and longitude 43.0°E which put the center about 240 miles (385 km) west of Mahajanga, Madagascar.  Fytia was moving toward the east at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 973 mb.

Tropical Cyclone Fytia rapidly intensified to the equivalent of a hurricane/typhoon early on Friday.  The inner end of a rainband wrapped around the center of Fytia’s circulation.  A small circular eye formed at the center of Tropical Cyclone Fytia.  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 Fytia’s circulation.  Storms near the core of Fytia 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 Fytia was small.  Winds to tropical storm force extended out 25 miles (40 km) from the center of Fytia’s circulation.  Winds to tropical storm force extended out 90 miles (145 km) from the center of Tropical Cyclone Fytia.

The Hurricane Intensity Index (HII) for Tropical Cyclone Fytia was 13.9.  The Hurricane Size Index (HWISI) was 9.3 and the Hurricane Wind Intensity Size Index (HWISI) was 23.2  Tropical Cyclone Fytia was similar in size and intensity to Hurricane Hanna when Hanna hit South Texas in 2020.

Tropical Cyclone Fytia will move through an environment very favorable for intensification during the next 12 hours.  Fytia 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 Mozambique Channel.  The upper level winds are weak in the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Fytia will intensify during the next 12 hours.  Fytia could rapidly intensify to the equivalent of a major hurricane.

Tropical Cyclone Fytia will move around the southwestern part of a high pressure system that is over the South Indian Ocean.  The high pressure system will steer Fytia toward the east-southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Fytia will reach the west coast of Madagascar between Soalala and Besalampy on Friday night.

Tropical Cyclone Fytia will bring strong winds and locally heavy rain to the coast of west central Madagascar and to central Madagascar.  Fytia could cause major damage in those areas.  Heavy rain is very likely to cause flash floods in some locations.  Tropical Cyclone Fytia could also cause a storm surge of up to 10 feet (3 meters) along parts of the west coast of Madagascar.

Tropical Cyclone Dudzai Strengthens to Equivalent of Cat. 4 Hurricane

Tropical Cyclone Dudzai strengthened to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Monday.  At 4:00 p.m. EST on Monday the center of the Tropical Cyclone Dudzai was located at latitude 17.1°S and longitude 78.0°E which put the center about 775 miles (1255 km) south-southeast of Diego Garcia.  Dudzai was moving toward the south-southeast at 3 m.p.h. (5 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 948 mb.

Tropical Cyclone Dudzai continued to intensify on Monday afternoon.  Dudzai strengthened to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.  A small circular eye was present at the center of Tropical Cyclone Dudzai.  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 Dudzai’s circulation.  Storms near the core of Dudzai generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to continue to decrease.

The circulation around Tropical Cyclone Dudzai was small.  Winds to hurricane/typhoon force extended out 30 miles (50 km) from the center of Dudzai’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Tropical Cyclone Dudzai.

The Hurricane Intensity Index (HII) for Tropical Cyclone Dudzai is 25.1.  The Hurricane Size Index (HSI) is 10.5 and the Hurricane Wind Intensity Size Index (HWISI) is 35.6.  Tropical Cyclone Dudzai is similar in intensity to Hurricane Harvey when Harvey hit Texas in 2017.  Dudzai is slightly smaller than Harvey was.

Tropical Cyclone Dudzai will move through an environment that will become less favorable for intensification during the next 24 hours.  It will move under the middle of an upper level ridge that is over the South Indian Ocean.  The upper level winds are weak in the middle of the ridge and there will be little vertical wind shear.  However, the strong winds in the lower levels of Dudzai’s circulation will mix cooler water to the surface of the South Indian Ocean.  The cooler water will transfer less energy into Tropical Cyclone Dudzai.  Tropical Cyclone Dudzai is likely to weaken during the next 24 hours due to the upwelling of cooler water.

Tropical Cyclone Dudzai will move through a region where the steering winds are weak during the next 12 hours.  Dudzai is likely to move slowly toward the south during that time period.  A high pressure system that is southwest of Dudzai will start to steer it toward the west on Wednesday.  On its anticipated track, Tropical Cyclone Dudzai will remain far to the south of Diego Garcia.

Tropical Cyclone Grant Passes South of Diego Garcia

Tropical Cyclone Grant passed south of Diego Garcia on Tuesday night.  At 10:00 a.m. EST on Wednesday the center of Tropical Cyclone Grant was located at latitude 15.8°S and longitude 69.2°E which put the center about 625 miles (1005 km) south-southwest of Diego Garcia.  Grant was moving toward the west at 26 m.p.h. (43 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 958 mb.

Tropical Cyclone Grant weakened as it passed south of Diego Garcia on Tuesday night.  An eye was no longer visible on satellite images of Grant.  Bands of showers and thunderstorms were revolving around the center of Grant’s circulation.  Storms near the center of Grant generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure was increasing.

The circulation around Tropical Cyclone Grant was still very small.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Grant’s circulation.  Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Cyclone Grant.

The Hurricane Intensity Index (HII) for Tropical Cyclone Grant was 20.6.  The Hurricane Size Index (HSI) was 8.9 and the Hurricane Wind Intensity Size Index (HWISI) was 29.5.

Tropical Cyclone Grant will move through an environment unfavorable for intensification during the next 24 hours.  Grant will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the northern part of an upper level ridge over the South Indian Ocean. The upper level ridge will produce easterly winds that will blow toward the top of Grant’s circulation.  Those winds will cause moderate vertical wind shear.  The moderate wind shear will cause Tropical Cyclone Grant to continue to weaken during the next 24 hours.

Tropical Cyclone Grant will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Grant toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Grant will move farther away from Diego Garcia.  Grant will pass north of Rodrigues in 48 hours.

Tropical Cyclone Hayley Brings Wind and Rain to Western Australia

Tropical Cyclone Hayley brought wind and rain to Western Australia on Tuesday.  At 10:00 a.m. EST on Tuesday the center of Tropical Cyclone Hayley was located at latitude 16.7°S and longitude 123.7°E which put the center about 50 miles (80 km) north-northwest of Derby, Australia.  Hayley was moving toward the east at 15 m.p.h. (24 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 969 mb.

A Warning was in effect for the region from north of Beagle Bay to south of Kuri Bay, Australia.

Tropical Cyclone Hayley made landfall on the coast of Western Australia south of Lombadina on Tuesday morning.  Hayley moved across the northern part of the Dampier Peninsula.  Tropical Cyclone Haley was currently over King Sound.

The circulation around Tropical Cyclone Hayley was small.  Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of Hayley’s circulation.  Winds to tropical storm force extended out 100 miles (160 km) from the center of Tropical Cyclone Hayley.

The Hurricane Intensity Index (HII) for Tropical Cyclone Hayley was 12.7.  The Hurricane Size Index (HSI) was 7.9 and the Hurricane Wind Intensity Size Index (HWISI) was 20.6.

Tropical Cyclone Hayley will move around the northeastern part of an upper level trough over Western Australia.  The upper level trough will steer Hayley toward the east during the next 24 hours.  On its anticipated track, Tropical Cyclone Hayley will make another landfall in Western Australia north of Derby in a few hours.

Tropical Cyclone Hayley will bring strong winds and locally heavy to parts of Western Australia north and east of Derby.  Heavy rain could cause flash floods in some locations,

The Australian Bureau of Meteorology has issued a Severe Weather Warning for heavy rainfall for parts of the Kimberley District.

Elsewhere over the South Indian Ocean, Tropical Cyclone Grant was moving south-southeast of Diego Garcia.  At 10:00 a.m. EST on Tuesday the center of Tropical Cyclone Grant was located at latitude 14.8°S and longitude 75.1°E which put the center about 565 miles (910 km) south-southeast of Diego Garcia.  Grant was moving toward the west-southwest at 16 m.p.h. (26 km/h).  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 950 mb.

Tropical Cyclone Hayley Rapidly Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Hayley rapidly intensified to the equivalent of a hurricane/typhoon northwest of Australia early on Monday.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Hayley was located at latitude 15.8°S and longitude 120.3°E which put the center about 210 miles (340 km) northwest of Broome, Australia.  Hayley was moving toward the southeast at 7 m.p.h. (11 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 976 mb.

The Australian Bureau of Meteorology issued a Warning for the portion of the coast from north of Broome to Cockatoo Island.  The Warning included the Dampier Peninsula and Derby.

The Australia Bureau of Meteorology issued a Watch for the region from east of Derby to Kuri Bay.

Tropical Cyclone Hayley rapidly intensified to the equivalent of a hurricane/typhoon early on Monday.  The inner end of a rainband wrapped around the center of Hayley’s circulation.  A small eye with a diameter of 10 miles (16 km) formed at the center of Tropical Cyclone Hayley.  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 Hayley’s circulation.  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 Hayley was very small.  Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of Hayley’s circulation.  Winds to tropical storm force extended out 65 miles (105 km) from the center of Tropical Cyclone Hayley.

The Hurricane Intensity Index (HII) for Tropical Cyclone Hayley was 12.7.  The Hurricane Size Index (HSI) was 7.1 and the Hurricane Wind Intensity Size Index (HWISI) was 19.8.

Tropical Cyclone Hayley will move through an environment favorable for intensification during the next 12 hours.  Hayley will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of a small upper level ridge that is northwest of Australia.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Cyclone Hayley is likely to continue to  intensify during the next 12 hours. Hayley could intensify rapidly because its circulation is so small.  Tropical Cyclone Hayley will move under the northeastern part of an upper level trough that is near the west coast of Australia in about 12 hours.  The upper level trough will produce northwesterly winds that will blow toward the top of Hayley’s circulation.  Those winds will cause the vertical wind shear to increase.  Tropical Cyclone Hayley will start to weaken when the vertical wind shear increases.

The upper level trough will steer Tropical Cyclone Hayley toward the east-southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Hayley will make landfall in the northern part of the Dampier Peninsula between Beagle Bay and Cape Leveque in 24 hours.

Tropical Cyclone Hayley is likely to be the equivalent of a hurricane/typhoon at the time of landfall.  Hayley will bring strong winds and heavy rain to the Dampier Peninsula and parts of Western Australia.  Heavy rain could cause flash floods in some locations.  Tropical Cyclone Hayley could also cause a storm surge of up to 10 feet (3 meters) along portions of the coast near where the center makes landfall.

Elsewhere over the South Indian Ocean, Tropical Cyclone Grant intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale southeast of Diego Garcia.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Grant was located at latitude 13.8°S and longitude 80.0°E which put the center about 710 miles (1145 km) southeast of Diego Garcia.  Grant was moving toward the west at 12 m.p.h. (19 km/h).  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 944 mb.

The Hurricane Intensity Index for Tropical Cyclone Grant was 28.3.  The Hurricane Size Index (HSI) was 10.4 and the Hurricane Wind Intensity Size Index (HWISI) was 38.7.  Tropical Cyclone Grant was similar in size and intensity to Hurricane Charley when Charley hit Southwest Florida in 2004.