Subtropical Storm Andrea Develops Southwest of Bermuda

Subtropical Storm Andrea developed southwest of Bermuda on Monday afternoon.  An Air Force Reserve Hurricane Hunter aircraft investigated an area of low pressure southwest of Bermuda on Monday afternoon.  The aircraft determined that there was a well defined center of circulation at the surface and the National Hurricane Center designated the system as Subtropical Storm Andrea.  At 11:00 p.m. EDT on Monday the center of Subtropical Storm Andrea was located at latitude 29.5°N and longitude 68.7°W which put it about 300 miles (485 km) southwest of Bermuda.  Andrea was moving toward the north at 12 m.p.h. (19 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 1006 mb.

The circulation around Subtropical Storm Andrea was asymmetrical.  Most of the thunderstorms and the strongest winds were occurring northeast of the center of circulation.  Bands in other parts of the circulation consisted primarily of lower clouds and showers and the winds were weaker in those parts of Andrea.  An upper low northeast of the Bahamas was producing southerly winds which were blowing toward the top of the circulation.  Those winds were creating moderate vertical wind shear and the shear was the primary cause of the asymmetrical structure of Subtropical Storm Andrea.  The asymmetrical structure was the reason why Andrea was classified as a subtropical storm.  Winds to tropical storm force extended out about 65 miles (105 km) from the center of Andrea in the northeastern quadrant of the circulation.

Subtropical Storm Andrea will move through an environment marginally favorable for intensification on Tuesday.  Andrea will move over water where the Sea Surface Temperature is near 25°C.  The upper low will continue to cause moderate vertical wind shear, but the low could weaken slightly on Tuesday.  If the upper level winds weaken, then Andrea could get stronger.  Stronger upper level westerly winds could affect Subtropical Storm Andrea on Wednesday.  Those winds will cause stronger vertical wind shear which will weaken Andrea.

The upper level low northeast of the Bahamas will steer Subtropical Storm Andrea toward the north during the next 12-18 hours.  After that time the upper level westerly winds are likely to steer Andrea more toward the east.  On its anticipated track Subtropical Storm Andrea could be near Bermuda in about 36 hours.  Andrea could bring gusty winds and rain showers to Bermuda on Wednesday.

Weaker Tropical Cyclone Ann Nears Northern Queensland

A weaker Tropical Cyclone Ann neared northern Queensland on Monday.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Ann was located at latitude 14.4°S and longitude 148.4°E which put it about 230 miles (370 km) east-northeast of Cooktown, Australia.  Ann was moving toward the west-northwest at 14 m.p.h. (22km/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 996 mb.  The Australian Bureau of Meteorology issued a Tropical Cyclone Warning that extended from Lockhart River to Cooktown including Coen and Lizard Island.

The circulation around Tropical Cyclone Ann weakened on Monday because of a drier, more stable environment and more vertical wind shear.  Low level convergence pulled drier, more stable air closer to the center of Tropical Cyclone Ann.  The drier, more stable air caused many of the stronger thunderstorms to weaken.  Despite the drier, more stable environment stronger thunderstorms redeveloped south of the center of circulation late on Monday.  Tropical Cyclone Ann was moving near the northwestern portion of an upper level ridge.  The ridge produced easterly winds which caused moderate vertical wind shear.  The wind shear also contributed to the weakening of storms in the northern half of the circulation.

Tropical Cyclone Ann continued to have a distinct low level center of circulation despite the less favorable environment.  However, the wind field exhibited a more asymmetric structure.  The strongest winds were occurring in an area of thunderstorms south of the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center in the southern half of the circulation.  Winds to tropical storm force only extended out about 50 miles (80 km) from the center in the northern half of the circulation.

Tropical Cyclone Ann will continue to move through a less favorable environment during the next 24 hours.  Ann will move over water in the Coral Sea where the Sea Surface Temperature is near 27.5°C.  It will continue to move through a region where there is drier, more stable air and the upper level ridge will continue to cause moderate vertical wind shear.  The drier, more stable air and moderate vertical wind shear will prevent significant intensification.  Tropical Cyclone Ann could maintain its intensity during the next 12 hours, but it may weaken when it approaches the coast of the Cape York Peninsula.

Tropical Cyclone Ann will move north of a ridge which will steer Ann toward the west-northwest.  On its anticipated track Tropical Cyclone Ann will make landfall on the Cape York Peninsula in northern Queensland in about 24 hours.  Ann will bring some gusty winds, but the greatest risk will be locally heavy rain.

Tropical Cyclone Ann Strengthens Over Coral Sea

Tropical Cyclone Ann strengthened over the Coral Sea on Sunday.  At 11:00 p.m. EDT on Sunday the center of Tropical Cyclone Ann was located at latitude 15.4°S and longitude 153.6°E which put it about 565 miles (910 km) east of Cairns, Australia.  Ann was moving toward the west-northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 987 mb.

The circulation around Tropical Cyclone Ann exhibited greater organization on Sunday.  There were indications on satellite images that a cloud filled eye might be trying to form at the center of circulation.  A broken ring of 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 Tropical Cyclone Ann.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out about 100 miles (160 km) from the center of circulation.

Tropical Cyclone Ann will be moving through an environment that contains factors favorable for intensification and a factor that will inhibit potential intensification.  Ann will move over water where the Sea Surface Temperature is near 28°C.  So, there will be sufficient energy in the upper ocean to support intensification.  Tropical Cyclone Ann will move north of an upper level ridge.  The ridge will produce easterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Cyclone Ann is surrounded by drier more stable air and the drier air is the factor that will inhibit intensification.  So far, the circulation around Ann has kept the drier air outside the tropical cyclone.  If the drier air remains outside the circulation, then Tropical Cyclone Ann would have a chance to strengthen.  However, if the drier air gets pulled into the circulation, then Ann will weaken.  The higher probability is that Tropical Cyclone Ann could maintain its intensity or weaken slowly during the next day or two depending on what happens to the drier air.

Tropical Cyclone Ann will move north of an area of high pressure, which will steer the tropical cyclone toward the west-northwest.  On its anticipated track Ann will approach the Cape York Peninsula north of Coen in less than 48 hours.  Tropical Cyclone Ann could bring gusty winds and locally heavy rain to northern Queensland.

Tropical Cyclone Ann Forms Over Coral Sea

Tropical Cyclone Ann formed over the Coral Sea on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Ann was located at latitude 16.3°S and longitude 158.7°E which put it about 875 miles (1410 km) east of Cairns, Australia.  Ann was moving toward the west at 5 m.p.h. (8 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 999 mb.

A distinct low level center of circulation became more evident in satellite images of a low pressure system over the eastern Coral Sea on Saturday and the system was designated as Tropical Cyclone Ann.  A rainband wrapped around the southern and western sides of the center of circulation.  A microwave satellite image indicated that the band may have wrapped completely around the center in the middle levels of the circulation.  Storms near the center of circulation began to generate upper level divergence which was pumping mass away from the tropical cyclone.  The circulation around Tropical Cyclone Ann was relatively small.  Winds to tropical storm force extended out about 85 miles (135 km) from the center of circulation in the southern half of Ann.

Tropical Cyclone Ann will move through an environment somewhat favorable for intensification during the next day or two.  Ann will move over water where the Sea Surface Temperature is near 28.5°C.  It will move south of an upper level ridge.  The ridge will produce easterly winds which will cause some vertical wind shear.  The shear will inhibit intensification, but it is not likely to be strong enough to prevent intensification.  Tropical Cyclone Ann is likely to intensify during the next 24 hours.

The ridge will steer Tropical Cyclone Ann toward the west-northwest during the next two to three days.  On its anticipated track Tropical Cyclone Ann will approach the Cape York Peninsula in northern Queensland in about 72 hours.  Ann could bring gusty winds and locally heavy rain.

Elsewhere around the tropics in the southern hemisphere, Tropical Cyclone Lili was weakening near the coast of East Timor.  At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Lili was located at latitude 9.1°S and longitude 126.8°E which put it about 120 miles (195 km) east-northeast of Suai, East Timor.  Lili was moving toward the west at 4 m.p.h. (6 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 1000 mb.

Tropical Cyclone Lili Forms Over Timor Sea

Tropical Cyclone Lili formed over the Timor Sea on Thursday.  At 11:00 a.m. EDT on Thursday the center of Tropical Cyclone Lili was located at latitude 9.1°S and longitude 128.8°E which put it about 100 miles (160 km) southeast of Tutuala, East Timor.  Lili was moving toward the south-southwest at 5 m.p.h. (8 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 991 mb.

The circulation around a low pressure system over the Timor Sea exhibited more organization on Thursday and the system was designated as Tropical Cyclone Lili.  Several bands of showers and thunderstorms began to wrap around the low level center of circulation.  Additional bands of showers and thunderstorms began to develop around the periphery of the circulation.  Storms near the center of circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.   The circulation around Tropical Cyclone Lili was relatively small.  Winds to tropical storm force only extended out about 60 miles (95 km) from the center of circulation.

Tropical Cyclone Lili will move through an environment favorable for intensification during the next 12 to 24 hours.  Lili will move over water where the Sea Surface Temperature is near 29°C.  It will move under the western portion of an upper level ridge.  Tropical Cyclone Lili will move through an area where the upper level winds are not too strong during the next 12 to 24 hours and there will not be a lot of vertical wind shear.  Lili could intensify during that period.  Tropical Cyclone Lili will move closer to the western end of the ridge in about 24 hours.  There are strong northerly winds blowing around the western end of the ridge and there will be more vertical wind shear.  If the shear increases, then the circulation around Lili is likely to weaken.

Tropical Cyclone Lili will move north of a subtropical ridge.  The ridge is likely to steer Lili more toward the west.  On its anticipated track Tropical Cyclone Lili could reach East Timor in about 36 hours.  Lili will bring gusty winds, but heavy rain and flooding are greater risks.  An alternative forecast scenario is possible.  If the vertical wind shear is not too strong and the vertical structure of Tropical Cyclone Lili remains intact, the upper level ridge could steer Lili more toward the south.  In that case Tropical Cyclone Lili could bring rain to Western Australia.

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.

Tropical Cyclone Fani Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Fani strengthened to the equivalent of a hurricane/typhoon over the Bay of Bengal on Monday.  At 5:00 p.m. EDT on Monday the center of Tropical Cyclone Fani was located at latitude 11.4°N and longitude 86.9°E which put it about 800 miles (1290 km) south of Kolkata (Calcutta), India.  Fani was moving toward the north 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 974 mb.

The circulation around Tropical Cyclone Fani exhibited greater organization on Monday.  The inner end of a rainband wrapped most of the way around the eastern and northern sides of the center of circulation.  Although there was still a break on the southwestern side of the center, an eye may have been forming at the center of circulation.  Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Fani and the circulation was much more symmetrical.  Storm around the core were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out about 140 miles (225 km) from the center of circulation.

Tropical Cyclone Fani will move through an environment favorable for intensification during the next several days.  Fani will move over water where the Sea Surface Temperature is near 31°C.  It will move under the axis of an upper level ridge where the winds are weak.  Very warm water and little vertical wind shear will allow Tropical Cyclone Fani to intensify during the next 48 hours.  It could intensify rapidly once the inner core is fully developed.  Fani is likely to strengthen into the equivalent of a major hurricane during the next  2 to 3 days.

Tropical Cyclone Fani will move around the western end of a subtropical ridge during the next few days.  The ridge will steer Fani in a generally northward direction.  On its anticipated track Tropical Cyclone Fani could approach the coast of India southwest of Kolkata in three or four days.  Fani could be the equivalent of a major hurricane when it approaches the coast.  Tropical Cyclone Fani has the potential to cause major wind damage.  It will also generate a dangerous storm surge along the coast.  Heavy rain will create the potential for fresh water flooding in inland locations.  The greatest risks at this time are for the Indian states of Orissa and West Bengal.

Tropical Cyclone Fani Develops East of Sri Lanka

Tropical Cyclone Fani developed over the southern Bay of Bengal east of Sri Lanka on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Cyclone Fani was located at latitude 7.8°N and longitude 88.6°E which put it about 635 miles (1020 km) east-southeast of Chennai, India.  Fani was moving toward the north-northwest at 15 m.p.h. (24 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 989 mb.

A distinct low level center of circulation formed on the eastern side of a cluster of thunderstorms over the southern Bay of Bengal on Saturday and the India Meteorological Department designated the system as Tropical Cyclone Fani.  The circulation around Fani was still organizing.  Bands of showers and thunderstorms were developing.  Many of the stronger thunderstorms were developing in two clusters which were east and northwest of the center of circulation.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out about 100 miles (160 km) from the center of circulation.

Tropical Cyclone Fani will move into an environment that is more favorable for intensification.  Fani is currently under the southern part of an upper level ridge.  The ridge is producing easterly winds which are causing moderate vertical wind shear.  The wind shear is the primary factor slowing the intensification of Tropical Cyclone Fani.  Fani is forecast to move under the axis of the ridge where the upper level winds are weaker.  There will be less vertical wind shear when that happens.  Tropical Cyclone Fani will move over water where the Sea Surface Temperature is near 31°C.  So, intensification is very likely when the wind shear decreases.  Fani is likely to strengthen into the equivalent of a hurricane/typhoon.  Rapid intensification could occur if the inner core of the circulation becomes more well developed.

Tropical Cyclone Fani will move around the western end of a subtropical ridge over southeast Asia.  The ridge will steer Fani toward the north-northwest during the next several days.  It will move more toward the north when it moves around the western end of the ridge.  On its anticipated track Tropical Cyclone Fani will move toward the northern Bay of Bengal.