Tag Archives: HWISI

Tropical Cyclone Trevor Makes Landfall in the Northern Territory

Tropical Cyclone Trevor made landfall on the coast of the Northern Territory of Australia southeast of Port McArthur early on Saturday.  At 11:00 p.m. EDT on Friday the center of Tropical Cyclone Trevor was located at latitude 16.5°S and longitude 137.0°E which put it about 50 miles (80 km) east-southeast of Port McArthur, Northern Territory.  Trevor was moving toward the southwest 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. (230 km/h).  The minimum surface pressure was 949 mb.  A Tropical Cyclone Warning was in effect from Port Roper, Northern Territory to Burketown, Queensland.

Tropical Cyclone Trevor intensified into the equivalent of a major hurricane before it made landfall.  The Hurricane Intensity Index (HII) for Trevor was 17.8.  The Hurricane Size Index (HSI) was 16.8 and the Hurricane Wind Intensity Size Index (HWISI) was 34.6.  Tropical Cyclone Trevor was capable of causing major damage when it made landfall.  It could have generated a storm surge of up to 12 feet (4 meters at the coast).

Tropical Cyclone Trevor will continue to move southwestward and it will gradually weaken as it moves farther inland.  Trevor will also drop heavy rainfall while it moves inland.  Flood Watches have been issued for parts of the eastern Northern Territory and western Queensland.

Elsewhere, Tropical Cyclone Veronica was advancing slowly toward the coast of Western Australia.  At 11:00 p.m. EDT on Friday the center of Tropical Cyclone Veronica was located at latitude 18.9°S and longitude 117.1°E.  Veronica was moving toward the south 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 962 mb.  A Tropical Cyclone Warning was in effect for the portion of the coast from Wallal to Mardie including Port Hedland and Karratha.

The structure of Tropical Cyclone Veronica changed significantly on Friday.  A large eye with a diameter of about 40 miles (65 km) developed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Veronica.  Winds to hurricane/typhoon force extended out about 45 miles (75 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.

Tropical Cyclone Veronica is moving around the western end of a subtropical high pressure system.  The high will steer Veronica toward the southeast during the next 24 hours.  On its anticipated track Tropical Cyclone Veronica will make landfall on the coast of Western Australia west of Port Hedland in about 24 hours.  Veronica will be the equivalent of a hurricane/typhoon when it makes landfall and it will be capable of causing serious damage.

Tropical Cyclones Veronica and Trevor Threaten Australia

Tropical Cyclones Veronica and Trevor posed threats to Australia on Wednesday night.  Tropical Cyclone Veronica intensified very rapidly into the equivalent of a major hurricane on Wednesday off the coast of Western Australia.  At 11:00 p.m. EDT on Wednesday the center of Tropical Cyclone Veronica was located at latitude 16.5°S and longitude 117.6°E which put it about 275 miles (445 km) north-northwest of Port Hedland, Australia.  Veronica was moving toward the south-southwest at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 145 m.p.h. (230 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 929 mb.  A Tropical Cyclone Watch was in effect for the portion of the coast from Pardoo to Mardie including Port Hedland and Karratha.

Tropical Cyclone Veronica intensified very rapidly during the past 24 hours.  Veronica strengthened from the equivalent of a tropical storm to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.  A small pinhole eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the core were generating strong upper level divergence which was pumping mass away from the tropical cyclone.

Tropical Cyclone Veronica had a large circulation.  Winds to hurricane/typhoon force extended out about 45 miles (75 km) from the center of circulation.  Winds to tropical storm force extended out about 200 miles (320 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Veronica was 29.8.  The Hurricane Size Index (HSI) was 18.6 and the Hurricane Wind Intensity Size Index (HWISI) was 48.4.

Tropical Cyclone Veronica will remain in an environment favorable for strong tropical cyclones for several more days.  Veronica will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Veronica could strengthen into the equivalent of a Category 5 hurricane during the next 24 hours.  If a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause fluctuations in the intensity of Veronica.

Tropical Cyclone Veronica will move around the western end of a subtropical ridge.  The ridge will steer Veronica toward the south-southwest.  Tropical Cyclone Veronica could move toward the south-southeast after it rounds the western end of the ridge.  On its anticipated track Tropical Cyclone Veronica could approach the coast of Western Australia in about three days.  Veronica could be the equivalent of a major hurricane at that time.

Tropical Cyclone Trevor moved over the eastern Gulf of Carpentaria on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Cyclone Trevor was located at latitude 13.1°S and longitude 141.1°E which put it about 55 miles (90 km) southwest of Weipa, Australia.  Trevor was moving toward the southwest at 2 m.p.h. (3 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 minium surface pressure was 988 mb.  A Tropical Cyclone Watch was in effect for the coast from Nhulunbuy to Karumba.

The circulation of Tropical Cyclone Trevor was gradually reorganizing as the center moved farther into the Gulf of Carpentaria.  Trevor will move over water where the Sea Surface Temperature is near 31°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Trevor will intensify during the next 48 hours and it could strengthen into the equivalent of a major hurricane.  On its anticipated track Trevor is forecast to approach the southwest of the Gulf of Carpentaria near Port McArthur in about 48 hours.

Rapidly Intensifying Tropical Cyclone Trevor Nears Cape York Peninsula

Rapidly intensifying Tropical Cyclone Trevor neared the Cape York Peninsula on Monday.  At 5:00 p.m. EDT on Monday the center of Tropical Cyclone Trevor was located at latitude 13.0°S and longitude 144.3°E which put it about 80 miles (130 km) east of Lockhart River, Australia.  Trevor was moving toward the west-southwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 955 mb.

The Australian Bureau of Meteorology issued Tropical Cyclone Warnings for the portion of the east coast of the Cape York Peninsula from Orford Ness to Cape Flattery, from Mapoon to Pormpuraaw on the west coast of the peninsula and for inland locations between the two coasts.

Tropical Cyclone Trevor rapidly intensified into the equivalent of a hurricane/typhoon on Monday.  An eye with a diameter of 15 miles (24 km) developed at the center of circulation.  The eye was surround by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Trevor.  Storms near the core were generating strong upper level divergence which was pumping mass away from the tropical cyclone in all directions.

The circulation around Tropical Cyclone Trevor was relatively small.  Winds to hurricane/typhoon force extended out about 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out about 90 miles (145 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Trevor was 17.8.  The Hurricane Size Index (HSI) was 11.0 and the Hurricane Wind Intensity Size Index (HWISI) was 28.8.

Tropical Cyclone Trevor will remain in an environment favorable for intensification for another 12 hours until it makes landfall.  Trevor will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Trevor could intensify into the equivalent of a major hurricane before it makes landfall.  It will take Trevor about 24 hours to cross the Cape York Peninsula.  Tropical Cyclone Trevor will weaken during that time.  Trevor will emerge over the Gulf of Carpentaria in about 36 hours and it will strengthen again after it gets back over water.

Tropical Cyclone Trevor will move around the northwestern portion of a subtropical ridge.  The ridge will steer Trevor toward the west-southwest.  On its anticipated track Tropical Cyclone Trevor will make landfall near or just to the south of Lockhart River in about 12 hours.    Trevor is forecast to move westward across the Cape York Peninsula.  it is likely to emerge over the Gulf of Carpentaria between Weipa and Aurukun in about 36 hours.  Tropical Cyclone Trevor will be capable of causing major damage.  It will bring strong winds and a storm surge to the area around Lockhart River.  Trevor will drop locally heavy rain over parts of the Cape York Peninsula and flooding could occur in some locations.  Tropical Cyclone Trevor could threaten the Northern Territory of Australia later this week.

Tropical Cyclone Idai Makes Landfall in Mozambique

Strong Tropical Cyclone Idai made landfall in Mozambique very close to Beira on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Idai was located at latitude 19.4°S and longitude 34.5°E which put it about 30 miles (50 km) northwest of Beira, Mozambique.  Idai was moving toward the west at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 958 mb.

The core of Tropical Cyclone Idai moved directly over Beira, Mozambique.  The eye moved over Beira.  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) at the time of landfall.  Winds to hurricane/typhoon force extended out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles from the center of Tropical Cyclone Idai.

The Hurricane Intensity Index (HII) for Tropical Cyclone Idai was 19.2 at the time of landfall.  The Hurricane Size Index (HSI) was 13.8 and the Hurricane Wind Intensity Size Index (HWISI) was 33.0.  Tropical Cyclone Idai was capable of causing very serious wind damage.  Both sides of the eyewall which contained the strongest winds moved over Beira.  The relatively slow rate at which Idai was moving would have resulted in a prolonged period of strong winds, which would have increased the potential for damage.

Clockwise rotation around Tropical Cyclone Idai would have produced strong southerly winds when Idai approached Beira.  Those winds would have pushed water into the mouth of the Rio Pungoe which is on the western side of Beria.  There could have been an enhanced storm surge of 12 to 18 feet (4 to 6 meters) in that area.  Beira is one of the largest cities in Mozambique and it has a population of over half a million people.  Idai could have cause very serious damage around Beira.

Tropical Cyclone Idai will move toward the west-northwest during the next day or two.  On its anticipated track Idai will move farther inland over Mozambique and it will eventually move over Zimbabwe.  Tropical Cyclone Idai will weaken steadily as it moves inland, but it will drop heavy rain over central Mozambique and over parts of Zimbabwe.  The heavy rain could cause flooding along portions of Rio Pungoe and Rio Buzi as well as other parts of central Mozambique and Zimbabwe.

Tropical Cyclone Idai Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Idai strengthened into the equivalent of a major hurricane over the Mozambique Channel on Monday.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Idai was located at latitude 18.2°S and longitude 42.0°E which put it about 490 miles (785 km) east-northeast of Beira, Mozambique.  Idai was moving toward the southwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 952 mb.

Tropical Cyclone Idai intensified into the equivalent of a major hurricane on Monday and then it appeared to begin an eyewall replacement cycle.  A rainband wrapped around the original eye and eyewall.  Convergence became concentrated on the outer eyewall and the inner eyewall began to dissipate.  The overall size of the circulation increased.  Winds to hurricane/typhoon force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 130 miles (210 km) from the center.

The Hurricane Intensity Index (HII) for Tropical Cyclone Idai was 20.6.  The Hurricane Size Index (HSI) was 15.2 and the Hurricane Wind Intensity Size Index (HWISI) was 35.8.

Tropical Cyclone Idai will remain in an environment favorable for intensification for several more days.  Idai will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Idai could strengthen further once the inner eyewall dissipates completely and the eyewall replacement cycle ends.

Tropical Cyclone Idai will move around the southeastern part of a subtropical ridge over southern Africa.  The ridge will steer Idai on a course that is a little south of due west.  On its anticipated track Tropical Cyclone Idai could reach the coast of Mozambique near Beira in less than 72 hours.  Idai could still be the equivalent of a major hurricane when it reaches the coast.

Tropical Cyclone Idai Rapidly Intensifies Into Equivalent of Hurricane/Typhoon

Tropical Cyclone Idai rapidly intensified into the equivalent of a hurricane/typhoon over the Mozambique Channel on Sunday.  At 11:00 p.m. EDT on Sunday the center of Tropical Cyclone Idai was located at latitude 17.4°S and longitude 43.2°E which put it about 75 miles (120 km) northwest of Maintirano, Madagascar.  Idai was moving toward the south at 1 m.p.h. (2 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 958 mb.

Tropical Cyclone Idai intensified rapidly on Sunday.  An eye was apparent on satellite imagery,  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Idai.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to hurricane/typhoon force extended out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center.

The Hurricane Intensity Index (HII) for Tropical Cyclone Idai was 17.8.  The Hurricane Size Index (HSI) was 10.7 and the Hurricane Wind Intensity Size Index (HWISI) was 28.5.

Tropical Cyclone Idai will continue to move through an environment favorable for intensification during the next day or two,  Idai will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Idai could intensify into the equivalent of a major hurricane during the next 24 hours.

Tropical Cyclone Idai will move around the eastern end of a subtropical ridge over southern Africa. The ridge will steer Idai toward the west during the next several days.  On its anticipated track Tropical Idai could approach the coast of Mozambique in about four days.  Idai could be the equivalent of a major hurricane at that time.

Tropical Cyclone Haleh Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Haleh strengthened into the equivalent of a major hurricane on Monday.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Haleh was centered at latitude 18.9°S and longitude 72.3°E which put it about 800 miles (1290 km) south of Diego Garcia.  Haleh was moving toward the south-southwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 948 mb.

Tropical Cyclone Haley rapidly intensified into the equivalent of a major hurricane during the past 24 hours.  A circular eye was clearly evident on satellite imagery.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Storms near the core of the circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Haleh.  The strongest bands were in the southern half of the circulation.  Bands in the northern half of the circulation consisted primarily of showers and lower clouds.

Winds to hurricane/typhoon force extended out about 50 miles (80 km) from the center of Tropical Cyclone Haleh.  Winds to tropical storm force extended out about 210 miles (330 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Haleh was 22.1.  The Hurricane Size Index (HSI) was 16.0 and the Hurricane Wind Intensity Size Index (HWISI) was 38.1.

Tropical Cyclone Haleh will move through an environment favorable for intensification during the next 24 hours.  Haleh will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds will be weak and there will be little vertical wind shear.  Tropical Cyclone Haleh could intensify during the next day or so.  Eventually, Haleh will move over cooler water and it will start to weaken when that occurs.

Tropical Cyclone Haleh will move around the western end of a subtropical ridge over the South Indian Ocean.  The ridge will steer Haleh toward the south-southwest.  On its anticipated track Tropical Cyclone Haleh is forecast to remain well to the southeast of Mauritius and La Reunion.

Typhoon Wutip Strengthens to Equivalent of a Category 5 Hurricane

Typhoon Wutip strengthened into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale on Monday.  At 5:00 a.m. EST on Monday the center of Typhoon Wutip was located at latitude 14.0°N and longitude 140.1°E which put it about 300 miles (480 km) west-northwest of Guam.  Wutip was moving toward the north-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km.h) and there were wind gusts to 195 m.p.h. (315 km/h).  The minimum surface pressure was 929 mb.

Typhoon Wutip completed an eyewall replacement cycle on Sunday and then it rapidly intensified into the equivalent of a Category 5 hurricane.  The inner eyewall dissipated completely and the outer eyewall contracted around a circular, symmetrical eye.  A ring of strong thunderstorms surrounded the new eye and the strongest winds were occurring in that ring of storms.  Storms near the core of Typhoon Wutip were generating strong upper level divergence which was pumping mass away from the typhoon.  Bands of showers and thunderstorms were revolving around the core of Wutip.

Winds to typhoon force extended out about 45 miles (75 km) from the center of Typhoon Wutip.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Wutip was 35.0.  The Hurricane Size Index (HSI) was 16.6 and the Hurricane Wind Intensity Size Index (HWISI) was 51.6.

Typhoon Wutip will remain in an environment capable of supporting a strong typhoon for another 12 to 24 hours.  Wutip will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  A band of stronger westerly winds north of the Philippines will approach Typhoon Wutip in another day or so.  Those winds will cause the vertical wind shear to increase and the increased shear will cause Wutip to weaken.

Typhoon Wutip will move southwest of a subtropical ridge over the Western North Pacific Ocean.  The ridge is forecast to steer Wutip in a west-northwesterly direction.  On its forecast track Typhoon Wutip will gradually move farther away from the Northern Marianas.

Typhoon Wutip Strengthens to Equivalent of a Major Hurricane South of Guam

Typhoon Wutip strengthened into the equivalent of a major hurricane south of Guam on Friday.  At 10:00 a.m. EST on Friday the center of Typhoon Wutip was located at latitude 10.1°N and longitude 144.7°E which put it about 240 miles (385 km) south of Guam.  Wutip was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 949 mb.

Tropical Storm Warnings were in effect for Guam, Rota and Faraulep.  Tropical Storm Watches have been issued for Tinian, Saipan, Agrihan and Pagan.

Typhoon Wutip was a very well organized tropical cyclone.  A small eye was at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Typhoon Wutip.  Storms near the core were generating upper level divergence which was pumping mass away from the typhoon.

Typhoon Wutip had a large circulation.  Winds to typhoon force extended out about 45 miles (75 km) from the center of circulation.  Winds to tropical storm force extended out about 185 miles (295 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Wutip was 22.1.  The Hurricane Size Index (HSI) was 17.3 and The Hurricane Wind Intensity Size Index (HWISI) was 39.4.  Typhoon Wutip was capable of causing major damage.

Typhoon Wutip may be near its peak intensity.  Wutip will move over water where the Sea Surface Temperature is near 29°C.  So, there is enough energy in the upper ocean to support a strong typhoon.  Typhoon Wutip has been in an area where the upper level winds were weak and there was little vertical wind shear.  The shear will remain small for another 12 to 24 hours.  Then an upper level trough will approach Typhoon Wutip from the west in a day or so.  The trough will bring southwesterly winds and the vertical wind shear will increase.  Wutip will start to weaken when the shear increases.

Typhoon Wutip will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  Wutip will gradually turn more toward the north while it moves around the end of the ridge.  On its anticipated track the core of Typhoon Wutip will pass west of Guam and the Northern Marianas.  Wutip could bring winds to tropical storm force to Guam and some of the other islands, which is why the warnings and watches were issued.

Tropical Cyclone Gelena Brings Wind and Rain to Rodrigues

Tropical Cyclone Gelena brought wind and rain to Rodrigues on Saturday.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Gelena was located at latitude 20.5°S and longitude 63.7°E which put it about 55 miles (90 km) southeast of Rodrigues, Mauritius.  Gelena was moving toward the east-southeast at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 959 mb.

Tropical Cyclone Gelena was the equivalent of a major hurricane when it moved past Rodrigues.  Winds to hurricane/typhoon force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Gelena was 20.6.  The Hurricane Size Index (HSI) was 15.9 and the Hurricane Wind Intensity Size Index (HWISI) was 36.5.

The northeastern part of the eyewall of Tropical Cyclone Gelena appeared to cross Rodrigues.  Winds to hurricane/typhoon force may have occurred when that part of the eyewall moved over the island.  Winds to tropical storm force will continue for a few more hours until Gelena moves farther away from Rodrigues.  Conditions on Rodrigues should gradually improve on Sunday while Tropical Cyclone Gelena moves farther away.  Gelena will weaken as it moves over colder water.

Elsewhere over South Indian Ocean, Tropical Cyclone Funani made a transition to an extratropical cyclone.  At 4:00 p.m. EST the center of Tropical Cyclone Funani was located at latitude 31.9°S and longitude 77.4°E which put it about 1390 miles (2245 km) southeast of Mauritius.  Funani was moving toward the southeast at 28 m.p.h. (45 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 996 mb.