Tag Archives: HWISI

Dorian Strengthens to Major Hurricane

Hurricane Dorian strengthened to a major hurricane on Friday afternoon.  Data from a reconnaissance plane indicated that Hurricane Dorian had strengthened to Category 3 on the Saffir-Simpson Scale on Friday afternoon, which meant it was a major hurricane.  At 2:00 p.m. EDT on Friday the center of Hurricane Dorian was located at latitude 24.8°N and longitude 70.3°W which put it about 625 miles (1005 km) east of West Palm Beach, Florida.  Dorian was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 970 mb.

Hurricane Watches had been issued for the Northwestern Bahamas.

The circulation around Hurricane Dorian exhibited much more impressive organization on satellite images and radar products generated by reconnaissance aircraft.  Clouds cleared out of the eye and it became even more circular.  The diameter of the eye was 21 miles (34 km).  The eye was surround by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  The overall appearance of Hurricane Dorian was more symmetrical.  Bands of showers and thunderstorms were revolving around the core of the circulation.  Storms around the core generating upper level divergence which was pumping mass away from the hurricane.

The circulation around Hurricane Dorian was still small.  Winds to hurricane force extended out about 25 miles from the center of circulation.  Winds to tropical storm force extended out about 100 miles from the center.  The Hurricane Intensity Index (HII) for Dorian was 20.6.  The Hurricane Size Index (HSI) was 9.0 and the Hurricane Wind Intensity Index (HWISI) was 29.6.  Hurricane Dorian was already capable of causing major damage.

Hurricane Dorian will move through an environment that is favorable for intensification.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Dorian could start a period of rapid intensification at any time.  Dorian will almost certainly intensify to Category 4 and there is the potential for it to strengthen to Category 5.  After Hurricane Dorian strengthens, eyewall replacement cycles could cause fluctuations in intensity.

A ridge of high pressure north of Hurricane Dorian is starting to turn Dorian more toward the west.  The high is forecast to steer Dorian toward the west during the next two to three days.  On its anticipated track Hurricane Dorian will be near the Northwestern Bahamas on Sunday and it will approach the southeast coast of Florida on Monday.  Dorian will reach the western end of the high when it gets close to the Florida coast.  Hurricane Dorian could slow down and turn northward on Tuesday.

Typhoon Lekima Moves Through Southern Ryukyu Islands

Powerful Typhoon Lekima moved through the southern Ryukyu Islands on Thursday.  At 5:00 p.m. EDT on Thursday the center of Typhoon Lekima was located at latitude 25.8°N and longitude 124.2°E which put it about 405 miles (655 km) south-southeast of Shanghai, China.  Lekima was moving toward the north-northwest at 13 m.p.h. (20 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. (270 km/h).  The minimum surface pressure was 935 mb.

An inner rainband wrapped around the original eye and eyewall of Typhoon Lekima and a larger outer eye formed around the original eye.  The inner eye remained intact and the strongest winds were occurring in a small ring of thunderstorms around the inner eye.  The diameter of the outer eye was about 60 miles (95 km).  Additional bands of showers and thunderstorms were revolving around the two concentric eyewalls.

The formation of two concentric eyewalls increased the size of the circulation around Typhoon Lekima.  Winds to typhoon force extended out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 275 miles (445 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 28.3.  The Hurricane Size Index (HSI) was 28.1 and the Hurricane Wind Intensity Size Index (HWISI) was 56.4.  Those indices indicated that Typhoon Lekima was capable of causing widespread significant damage.

The inner eye of Typhoon Lekima wobbled between Ishigakijima and Miyakojima on Thursday.  The inner eyewall appeared to pass over Taramajima and Minnajima.  No reports were available from a weather station on Taramajima.  Stations on Ishigakijima and Miyakojima reports winds to tropical storm force, but the strong inner eye passed between those two islands.

The formation of the larger outer eye probably indicates that an eyewall replacement cycle will occur.  Typhoon Lekima will weaken when the inner eyewall dissipates.  However, the circulation will remain large.  Typhoon Lekima will be in an environment favorable for strong typhoons during the next 24 hours.  Lekima will move over water where the Sea Surface Temperature is near 28.5°C.  It will move through a region where the upper level winds are not strong and there will not be a lot of vertical wind shear.  Typhoon Lekima will weaken because of an eyewall replacement cycle, but it will remain a large, powerful typhoon.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the north-northwest during the next several days.  On its anticipated track Typhoon Lekima could approach the coast of China south of Shanghai in about 24 hours.  It is likely to be a large typhoon at that time.

Elsewhere around the Western North Pacific Ocean, Typhoon Krosa was nearly stationary south of Iwo To on Thursday.  At 5:00 p.m. EDT on Thursday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 141.0°E which put it about 195 miles (315 km) south of Iwo To.  Krosa was nearly stationary.  The maximum sustained wind speed was 110 m.p.h. (180 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 950 mb.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 75 miles (120 km) from the center of circulation.  Winds to tropical storm force extended out about 250 miles (405 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Krosa was 19.2.  The Hurricane Size Index (HSI) was 28.4 and the Hurricane Wind Intensity Size Index (HWISI) was 47.6.

Typhoon Krosa is forecast to move slowly north toward Iwo To on Friday.  On its anticipated track Krosa could approach Iwo To in about 36 hours.  It will be a large typhoon capable of causing serious damage at that time.

Typhoons Lekima and Krosa Threaten Japanese Islands

Typhoons Lekima and Krosa threatened Japanese islands on Wednesday.  Typhoon Lekima posed a serious threat to the southern Ryukyu Islands and Typhoon Krosa was headed for Iwo To.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Lekima was located at latitude 22.4°N and longitude 126.0°E which put it about 190 miles (305 km) southeast of Ishigaki, Japan.  Lekmia was moving toward the northwest at 8 m.p.h. (13 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 925 mb.

Typhoon Lekima rapidly intensified into the equivalent of a major hurricane on Wednesday.  A small distinct 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.  Several 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 typhoon in all directions.

Typhoon Lekima had a large circulation.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 23.6.  The Hurricane Size Index (HSI) was 21.6 and the Hurricane Wind Intensity Size Index (HWISI) was 44.7.   Those indices indicated that Typhoon Lekima was capable of causing widespread major damage.

Typhoon Lekima will move through an environment favorable for intensification during the next 24 hours.  Lekima 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 not be a lot of vertical wind shear.  Typhoon Lekima could intensify further during the next day or so.  It is possible that a rainband could wrap around the existing eye and eyewall.  If a rainband wraps around the core of Lekima then an eyewall replacement cycle could cause weakening.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the northwest on Thursday.  On its anticipated track Typhoon Lekima will reach Ishigaki and the southern Ryukyu Islands in less than 24 hours.  Lekima will be capable of causing major damage to the southern Ryukyu Islands.  Typhoon Lekima will move more toward the north when it moves around the end of the subtropical ridge.  The center of Lekima could be northeast of Taiwan within 36 hours.  Typhoon Lekima could reach the east coast of China in less than three days.

At 5:00 p.m. EDT on Wednesday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 140.8°E which put it about 210 miles (340 km) south of Iwo To.  Krosa was moving toward the north-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 970 mb.

Former Tropical Storm Krosa strengthened into a typhoon on Wednesday.  The inner portion of a rainband wrapped around the center of circulation and an eye formed.  The inner part of the rainband closed around the eye and a circular ring of thunderstorms formed a closed eyewall.  The strongest winds were occurring in the eyewall.  Several bands of showers and thunderstorms were revolving around the core of Typhoon Krosa.  Storms near the center were pumping mass away to the east of the typhoon.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 225 miles (360 km) from the center.  The Hurricane Intensity Index for Typhoon Krosa was 11.5.  The Hurricane Size Index was 22.5 and the Hurricane Wind Intensity Size Index was 34.0.

Typhoon Krosa will move through an environment mostly favorable for intensification.  Krosa will move over water where the Sea Surface Temperature is near 29°C.  Upper level divergence from Typhoon Lekima which is to the west of Typhoon Krosa could cause some vertical wind shear.  The wind shear will not be great enough to prevent intensification, but it could slow the rate at which Typhoon Krosa strengthens.

Typhoon Krose will move into a region where the steering winds are weaker.  Typhoon Krosa is forecast to move slowly toward the north during the next two or three days.  On its anticipated track the center of Typhoon Krosa could be near Iwo To in about 48 hours.

Erick Rapidly Intensifies Into Major Hurricane

Erick rapidly intensified into a major hurricane over the the Central Pacific Ocean during Monday night.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Erick was located at latitude 13.4°N and longitude 142.8°W which put it about 920 miles (1485 km) east-southeast of Hilo, Hawaii.  Erick was moving toward the west at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 966 mb.

The core of Hurricane Erick intensified rapidly during the overnight hours.  The eye became more circular and distinct on infrared satellite images.  The diameter of the eye was about 12 miles (19 km) on Tuesday morning.  Thunderstorms in the ring around the eye grew taller and the wind speed around the eye increased quickly.  Storms around the core of Erick generated strong upper level divergence which pumped mass away from the hurricane.  Multiple bands of showers and thunderstorms were revolving around the core of the circulation.

The circulation around Hurricane Erick was relatively small.  Winds to hurricane force were occurring within 25 miles (40 km) of the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) of the center.  The Hurricane Intensity Index (HII) for Hurricane Erick was 20.6.  The Hurricane Size Index (HSI) was 8.2 and the Hurricane Wind Intensity Size Index (HWISI) was 28.8.

Hurricane Erick will remain in an environment favorable for intensification for about another 24 hours.  Erick 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 during the next day or so.  Hurricane Erick will approach an upper level trough east of Hawaii on Wednesday.  The trough will produce stronger southwesterly winds which will cause the vertical wind shear to increase.  Hurricane Erick will start to weaken when the wind shear increases.

Hurricane Erick will move south of a subtropical high pressure system over the Eastern and Central North Pacific Ocean.  The high will steer Erick toward the west during the next several days.  On its anticipated track Hurricane Erick could be south of Hawaii on Thursday night.

Elsewhere, Tropical Storm Flossie was nearing hurricane strength over the Eastern North Pacific Ocean.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Flossie was located at latitude 12.2°N and longitude 120.5°W which put it about 1015 mile (1635 km) southwest of the southern tip of Baja California.  Flossie was moving toward the west at 15 m.p.h. (24 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 999 mb.

Hurricane Barbara Starts to Weaken

Hurricane Barbara started to weaken on Wednesday when it moved over cooler water well to the east of Hawaii.  At 5:00 p.m. EDT on Wednesday the center of Hurricane Barbara was located at latitude 14.3°N and longitude 127.5°W which put it about 1860 miles (2990 km) east of Hilo, Hawaii.  Barbara was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 170 m.p.h. (275 km/h).  The minimum surface pressure was 941 mb.

The circulation around Hurricane Barbara remained very well organized.  There was a circular eye 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.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Barbara.  Storms near the core of the circulation were generating strong upper level divergence which was pumping mass away from the hurricane.  Winds to hurricane 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.

Hurricane Barbara still rated at Category 4 on the Saffir-Simpson Scale.  The Hurricane Intensity Index (HII) for Barbara was 28.3.  The Hurricane Size Index (HSI) was 16.5 and the Hurricane Wind Intensity Size Index (HWISI) was 44.8.

Hurricane Barbara will gradually move into an environment less capable of supporting a strong hurricane during the next few days.  Barbara will move over water where the Sea Surface Temperature is near 26°C.  As a result, Hurricane Barbara will extract less energy from the upper ocean and it will gradually weaken.  Barbara will move closer to an upper level trough located northeast of Hawaii.  When Hurricane Barbara gets closer to the trough later this week, stronger upper level southwesterly winds will create more vertical wind shear and the hurricane will weaken more quickly.

Hurricane Barbara will move south of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge will steer Barbara toward the west-northwest during the next 24 to 36 hours.  The ridge is forecast to strengthen on Friday and it will steer Hurricane Barbara more toward the west when that happens.  On its anticipated track Barbara could approach Hawaii in about five days.  It will be much weaker by that time.

Powerful Tropical Cyclone Fani Makes Landfall in India

Powerful Tropical Cyclone Fani made landfall near Puri, India on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Fani was located at latitude 19.4°N and longitude 85.8°E which put it about 25 miles (40 km) south of Puri, India.  Fani was moving toward the north-northeast at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 922 mb.

Tropical Cyclone Fani is a large dangerous system.  Winds to hurricane/typhoon force extend out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extend out about 225 miles (360 km) from the center over the Bay of Bengal.  The Hurricane Intensity Index (HII) for Tropical Cyclone Fani is 31.6.  The Hurricane Size Index (HSI) is 25.6 and the Hurricane Wind Intensity Size Index (HWISI) is 57.2.  Tropical Cyclone Fani has the potential to cause widespread significant damage.

Tropical Cyclone Fani will cause the greatest wind damage along the northeast coast of Odisha.  It could also produce a significant storm surge along the coast.  The surge will be highest in bays, estuaries and mouths of rivers.  Fani will drop heavy rain over northeast Odisha, West Bengal and portions of Bangladesh.  The heavy rain is likely to cause inland fresh water floods in some locations.  Wind and rain could cause damage around Kolkata (Calcutta), India.

An upper level trough over India will steer Tropical Cyclone Fani toward the northeast during the next 48 hours.  On its anticipated path Fani will pass near Bhubaneshwar, Cuttack and Baleshwar in Odisha.  Tropical Cyclone Fani could still be the equivalent of a hurricane/typhoon when it passes near those locations.  Fani will weaken steadily while it moves northeast.  It is likely to be the equivalent of a tropical storm when it passes near Kolkata.  Tropical Cyclone Fani will weaken to the equivalent of a tropical depression when it passes over Bangladesh, but it could still drop heavy rain around Dhaka.  Serious flooding could occur in Bangladesh while Fani weakens.

Dangerous Tropical Cyclone Fani Near Northeast India

Dangerous Tropical Cyclone Fani neared the coast of northeastern India on Thursday.  Fani rapidly intensified into the nearly the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  At 11:00 a.m. EDT on Thursday the center of Tropical Cyclone Fani was located at latitude 18.0°N and longitude 84.9°E which put it about 100 miles (160 km) east of Visakhapatnam, India.  Fani was moving toward the north at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 918 mb.

Tropical Cyclone Fani intensified rapidly during recent hours.  A circular eye with a diameter of 20 miles (32 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.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Fani.  Storms near the core were generating strong upper level divergence which was pumping mass away from the tropical cyclone.

The circulation around Tropical Cyclone Fani grew larger as it intensified.  Winds to hurricane/typhoon force extended out about 60 miles (95 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 Tropical Cyclone Fani was 33.3.  The Hurricane Size Index (HSI) was 21.7 and the Hurricane Wind Intensity Size Index (HWISI) was 55.0.  Tropical Cyclone Fani was capable of causing widespread significant damage.

Tropical Cyclone Fani is moving around the western end of a subtropical ridge.  The ridge is steering Fani toward the north.  On its anticipated track Tropical Cyclone Fani is likely to make landfall near Brahmapur, India in about 12 hours.  An upper level trough over India will steer Fani toward the northeast after it makes landfall.  Tropical Cyclone Fani could pass near Puri, Bhubaneswar, Cuttack and Kolkata (Calcutta), India.

Tropical Cyclone Fani will remain in a favorable environment during the 12 hours prior to landfall.  Fani will be over water where the Sea Surface Temperature is near 30°C.  It will move through an environment where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Fani will weaken after landfall.  The upper level trough over India will produce stronger southwesterly winds, which will increase the vertical wind shear after Fani makes landfall.  More wind shear and more friction over the land will cause Tropical Cyclone Fani to weaken to the equivalent of a tropical storm within 24 hours after landfall occurs.

Tropical Cyclone Fani is a dangerous tropical cyclone.  The strengthen and size of Fani will create the potential for widespread significant damage.  The counterclockwise circulation will cause the winds to blow water toward the coast along the northern Bay of Bengal.  Tropical Cyclone Fani could generate a storm surge of 15 to 20 feet (4.5 to 6.0 meters) in bays, estuaries and the mouths of rivers which act as funnels during storm surges.  Heavy rain could cause inland fresh water flooding in parts of northeastern India and Bangladesh.  The greatest threats are to the Indian states of Odisha (Orissa) and West Bengal.

Tropical Cyclone Fani Strengthens to Equivalent of Major Hurricane

Tropical Cyclone Fani strengthened to the equivalent of a major hurricane on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Tropical Cyclone Fani was located at latitude 14.1°N and longitude 83.9°E which put it about 670 miles (1080 km) south-southwest of Kolkata (Calcutta), India.  Fani was moving toward the northwest at 7 m.p.h. (11 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 946 mb.

Tropical Cyclone Fani strengthened on Tuesday.  A small eye emerged at the center of circulation.  The eye was surround by a ring of thunderstorms.  The storms were stronger in the western half of the ring and that was where the strongest winds were.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Fani.  The stronger bands were south and west of the center of Fani.  It appeared that a little drier air may have been pulled into the northern half of the circulation and the bands were weaker in that part of the circulation.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical cyclone.

Tropical Cyclone Fani had a moderately sized circulation.  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 Fani was 22.1.  The Hurricane Size Index (HSI) was 14.7 and the Hurricane Wind Intensity Size Index (HWISI) was 36.8.

Tropical Cyclone Fani will remain in an environment favorable for strong tropical cyclones during the next 24 to 36 hours.  Fani will move over water where the Sea Surface Temperature is near 30°C.  It will move near the western end of an upper level ridge and the upper level winds will not be too strong.  The major inhibiting factor will be the drier air over the northern half of the circulation.  Tropical Cyclone Fani could maintain its intensity and even strengthen during the next 24 hours if the drier air moistens over the warm water of the Bay of Bengal.

Tropical Cyclone Fani will move around the western end of a subtropical ridge on Wednesday.  Fani will move more toward the north when it rounds the end of the ridge.  An upper level trough approaching India from the west will turn Tropical Cyclone Fani toward the northeast in about 18 to 24 hours.  On its anticipated track Fani could approach the coast of Orissa state southwest of Kolkata in about 48 hours.  Tropical Cyclone Fani could bring strong winds to parts of Orissa and West Bengal.  Fani could also cause a significant storm surge along portions of the coast around the northern Bay of Bengal.  Locally heavy rain could also cause floods in Orissa and West Bengal.

Major Tropical Cyclone Kenneth Brings Strong Wind, Rain to Comoros

Major Tropical Cyclone Kenneth brought strong wind and rain to the Comoros on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Cyclone Kenneth was located at latitude 11.3°S and longitude 42.8°E which put it about 35 miles (55 km) north of the Comoros.  Kenneth was moving toward the west at 13 m.p.h. (20 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 954 mb.

Tropical Cyclone Kenneth intensified rapidly on Tuesday into the equivalent of a major hurricane.  A small circular eye appeared at the center of circulation on infrared satellite images.  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 the circulation.  Storms near the core were generating strong upper level divergence which was pumping mass away from the tropical cyclone in all directions.

Winds to hurricane/typhoon force extended out about 35 miles (55 km) from the center of Tropical Cyclone Kenneth.  Winds to tropical storm force extended out about 130 miles (215 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Kenneth was 20.1.  The Hurricane Size Index (HSI) was 11.0 and the Hurricane Wind Intensity Size Index (HWISI) was 31.1.  Tropical Cyclone Kenneth was capable of causing major damage.

The southern half of the eyewall of Tropical Cyclone Kenneth passed over northern Grande Comore (Njazidja).  Mitsamiouli and Mbeni were likely to have experienced winds to hurricane/typhoon force.  Strong winds may have also affected the capital, Moroni.  Major wind damage may have occurred in those areas.  Heavy rain falling on steep slopes may cause flash flooding.  Easterly winds blowing up the slopes would have enhanced rainfall and the greatest risks for flooding were on the eastern sides of the mountains.  Those easterly winds may have also generated a significant storms surge along the northeast coast of Grande Comore (Njazidja).

Tropical Cyclone Kenneth will move through an environment very favorable for intensification during the next 12 to 18 hours.  Kenneth will move over water where the Sea Surface Temperature is near 29°C.  It will move under the axis of an upper level ridge where the winds are weak and there will be little vertical wind shear.  Tropical Cyclone Kenneth is likely to intensify more while it moves across the Mozambique Channel.

Tropical Cyclone Kenneth will move north of a subtropical ridge.  The ridge will steer Kenneth a little to the south of due west.  On its anticipated track Tropical Cyclone Kenneth will make landfall on the north coast of Mozambique between Ibo and Mocimboa da Praia in about 18 hours.  Kenneth is likely to be a strong tropical cyclone at the time of landfall.  It will be capable of causing major wind damage and a storm surge at the coast.  Tropical Cyclone Kenneth will also drop heavy rain when it moves inland over northern Mozambique and it could cause additional flooding in that region.

Elsewhere over the South Indian Ocean, Tropical Cyclone Lorna moved gradually farther away from Diego Garcia.  At 5:00 p.m. EDT on Wednesday the center of Tropical Cyclone Lorna was located at latitude 10.3°S and longitude 84.8°E which put it about 855 miles (1380 km) east-southeast of Diego Garcia.  Lorna was moving toward the east at 4 m.p.h. (6 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 997 mb.

Major Tropical Cyclone Joaninha Brings Wind and Rain to Rodrigues

Major Tropical Cyclone Joaninha brought wind and rain to Rodrigues on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Joaninha was located at latitude 19.3°S and longitude 63.9°E which put it about 45 miles (75 km) from Rodrigues, Mauritius.  Joaninha was moving toward the southeast at 10 m.p.h. (16 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 946 mb.

Tropical Cyclone Joaninha was the equivalent of a major hurricane.  Winds to hurricane/typhoon force extended out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 180 miles (290 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Joaninha was 23.6.  The Hurricane Size Index (HSI) was 18.7 and the Hurricane Wind Intensity Size Index (HWISI) was 42.3.  Joaninha was capable of causing major damage.

The southwestern portion of the eyewall of Tropical Cyclone Joaninha was very near Rodrigues.  Winds to hurricane typhoon force were occurring in that part of the eyewall.  Winds to tropical storm force are likely to affect all of Rodrigues.  The circulation around Joaninha was somewhat asymmetrical.  Most of the stronger rainbands were occurring in the eastern half of the circulation and the heaviest rain is likely to fall east of Rodrigues.  However, heavy rain in the eyewall could cause flooding in some locations.

Tropical Cyclone Joaninha will move through an environment favorable for intensification during the next 24 hours.  Joaninha will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where there will be little vertical wind shear.  Tropical Cyclone Joaninha could strengthen slightly while it passes by Rodrigues.

An upper level trough near Madagascar will produce northwesterly winds which will steer Tropical Cyclone Joaninha toward the southeast.  On its anticipated track Joaninha will move away from Rodrigues on Tuesday.  Conditions in Rodrigues should improve gradually as Tropical Cyclone Joaninha moves away.

Elsewhere over the South Indian Ocean, weakening Tropical Cyclone Veronica was skirting the coast of Western Australia.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Veronica was located at latitude 21.1°S and longitude 115.4°E which put it about 140 miles (230 km) northeast of Learmonth, Australia.  Veronica was moving toward the southwest at 10 m.p.h. (16 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 992 mb.  Tropical Cyclone Veronica dropped heavy rain over parts of Western Australia and flooding was occurring in some locations.