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Typhoon Nock-ten Rapidly Intensifies Into Equivalent of a Major Hurricane

Typhoon Nock-ten intensified rapidly into the equivalent of a major hurricane on Friday.  At 10:00 p.m. EST on Friday the center of Typhoon Nock-ten was located at latitude 13.2°N and longitude 128.6°E which put it about 545 miles (880 km) east of Manila, Philippines.  Nock-ten was moving toward the west at 11 m.p.h. (18 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 935 mb.

Nock-ten is a very well organized typhoon.  There is an eye with a diameter of 14 miles (23 km) at the center of Typhoon Nock-ten.  The eye is surrounded by a ring of strong thunderstorms.  Additional bands of thunderstorms surround the core of the circulation.  Winds to typhoon force extend out about 40 miles (65 km) from the center.  Thunderstorms around the center are generating strong upper level divergence in all directions.  The divergence is pumping out large amounts of mass which allowed the surface pressure to decrease rapidly.

The Hurricane Intensity Index (HII) is 23.6 and the Hurricane Size Index (HSI) is 15.5.  The Hurricane Wind Intensity Size Index (HWISI) is 39.1.  Those indices indicate that Typhoon Nock-ten is capable of causing major regional wind damage.

Typhoon Nock-ten will continue to move through an environment that is very favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  Nock-ten could intensify more during the next 24 hours and it could become a super typhoon before it reaches the Philippines.

A subtropical ridge to the north of Nock-ten is steering the typhoon toward the west and that general motion is expected to continue.  On its anticipated track Typhoon Nock-ten could be near Catanduanes Island within 36 hours.  Nock-ten is likely to pass across southern Luzon and the center could move close to Manila.  Typhoon Nock-ten will be capable of causing major wind damage.  It will also bring heavy rain and create the potential for floods and mudslides.

Tropical Cyclone Yvette Turns Toward Western Australia

Tropical Cyclone Yvette turned toward western Australia on Friday.  At 1:00 p.m. EST on Friday the center of Tropical Cyclone Yvette was located near latitude 15.1°S and longitude 117.3°E which put it about 370 miles (600 km) north-northwest of Port Headland, Australia.  Yvette was moving toward the east-southeast at 8 m.p.h. (13 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.

An upper level ridge located to the northeast of Yvette is generating strong northeasterly winds which are blowing across the top of the tropical cyclone.  Those winds are creating strong vertical wind shear and for a time the strong upper levels winds sheared the top off of the circulation.  The upper level winds weakened slightly and new thunderstorms developed near the center of Tropical Cyclone Yvette.  The circulation of Yvette is very asymmetrical.  Most of the new thunderstorms are forming west of the center of circulation, although a few storms recently formed east of the center.  The upper level winds are also preventing upper level divergence to the east of Yvette.

Tropical Cyclone Yvette will be moving through an environment that will be only marginally favorable for intensification.  Yvette will move over water where the Sea Surface Temperature is near 29°C.  So, there is enough energy in the upper ocean to support intensification.  However, the strong upper level winds and vertical wind shear will inhibit intensification.  It is possible that the shear could decrease when Yvette moves east and gets closer to the core of the upper level ridge.  If the shear decreases, then some intensification may occur before Yvette reaches western Australia.

A subtropical ridge is steering Tropical Cyclone Yvette toward the east-southeast and that general motion is expected to continue.  On its anticipated track Tropical Cyclone Yvette will reach the coast of Western Australia in about 36 hours.  Landfall will likely occur between Cape Leveque and De Grey.  The highest probability is for a landfall near Bidyadanga.  Tropical Cyclone Yvette will produce locally heavy rain near where the center makes landfall.  Heavy rain could create the potential for flash floods.

Tropical Storm Nock-ten Strengthens on Its Way to the Philippines

Tropical Storm Nock-ten strengthened as it moved closer to the Philippines on Thursday.  At 10:00 p.m. EST on Thursday the center of Tropical Storm Nock-ten was located at latitude 12.0°N and longitude 132.7°E which put it about 850 miles (1370 km) east-southeast of Manila, Philippines.  Nock-ten was moving toward the west-northwest at 22 m.p.h. (35 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 987 mb.

Even though Tropical Storm Nock-ten moved quickly on Thursday the circulation continued to organized.  A mid-level eye appeared to develop on microwave satellite imagery.  Additional rainbands developed outside the core of the tropical storm.  Thunderstorms around the core of Nock-ten generated strong upper level divergence that pumped out mass in all directions.

Tropical Storm Nock-ten is moving through an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  An upper level ridge to the east of Nock-ten is producing southeasterly winds that are blowing toward the top of the circulation.  However, Tropical Storm Nock-ten is moving fairly rapidly toward the west-northwest.  The rapid motion is reducing the effective vertical wind shear, and so the wind shear is not inhibiting intensification.  Tropical Storm Nock-ten will continue to strengthen and it should become a typhoon within 12 to 24 hours.

A subtropical ridge to the north of Nock-ten is steering the tropical storm toward the west-northwest.  That general motion is expected to continue for another 24 to 36 hours.  The subtropical ridge is expected to strengthen after that time and it will steer Nock-ten more toward the west.  On its anticipated track Nock-ten will approach southeast Luzon in about 48 hours.

Nock-ten is likely to be a strong typhoon when it reaches the Philippines.  It could be the equivalent of a major hurricane.  In addition to strong winds, Nock-ten will generate a storm surge  and produce locally heavy rains.  It will produce a risk of floods and mudslides.

Tropical Storm Nock-ten Forms Near Yap

Tropical Storm Nock-ten formed near Yap on Wednesday.  At 10:00 p.m. EST on Wednesday the center of Tropical Storm Nock-ten was located at latitude 9.1°N and longitude 138.4°E which put it about 85 miles (140 km) southeast of Yap.  Nock-ten was moving toward the northwest at 16 m.p.h. (26 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 993 mb.

A distinct center of circulation developed in an area of thunderstorms near Yap and the system was named Tropical Storm Nock-ten.  The circulation of Nock-ten is still organizing.  A small well defined center exists at the core of the circulation.  A band of thunderstorms is beginning to wrap around the center.  Several additional bands of thunderstorms formed in the northern part of the circulation.  Thunderstorms near the center are beginning to generate upper level divergence which is pumping mass out to the west of the center.

Tropical Storm Nock-ten will move through an environment that is moderately favorable for intensification.  Nock-ten will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge north of Nock-ten is producing southeasterly winds which are blowing across the top of the tropical storm.  Those winds are preventing upper level divergence to east of Nock-ten.  Those winds are also causing moderate vertical wind shear which is slowing the rate of intensification.  When Nock-ten moves a little farther west, the vertical wind shear is expected to diminish and faster intensification could occur.  Nock-ten could intensify into a typhoon during the next several days.

A subtropical ridge north of Nock-ten is steering the tropical storm toward the northwest.  That general motion is expected to continue for another day or two.  The ridge could strengthen during the weekend and it could turn Nock-ten more toward the west in a couple of days.  On its anticipate track Tropical Storm Nock-ten could approach the Philippines in three or four days.  Nock-ten could be a typhoon by the time it reaches the Philippines.

Tropical Cyclone Yvette Develops Northwest of Australia

The circulation of a tropical low northwest of Australia continued to organize on Wednesday and the Australian Bureau of Meteorology named the system Tropical Cyclone Yvette.  At 7:00 a.m. EST on Wednesday the center of Tropical Cyclone Yvette was located at latitude 14.2°N and longitude 114.2°E which put it about 515 miles (830 km) northwest of Port Headland, Australia.  Yvette was making a slow clockwise loop and it was basically stationary.  The maximum sustained wind speed was 45 m.p.h. (70 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 991 mb.

The circulation of Tropical Cyclone Yvette is asymmetrical.  It has a well developed low level circulation but most of the thunderstorms are developing southwest of the center.  An upper level ridge over Australia is generating northeasterly winds which are blowing across the top of the circulation.  The moderate vertical wind shear is probably the reason why most of the thunderstorms are southwest of the center of circulation.  The upper level winds are inhibiting divergence to the east of Yvette, but they are enhancing the divergence to the west of the tropical cyclone.

The environmental factors are marginally favorable for intensification.  Tropical Cyclone Yvette will be moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds are forecast to weaken and the vertical wind shear could decrease during the next several day.  As a result, Tropical Cyclone Yvette could slowly strengthen.

Winds at the steering level are currently variable around Yvette and as a result the tropical cyclone has made several clockwise loops.  The upper level ridge over Australia is forecast to extend west and the ridge is expected to steer Tropical Cyclone Yvette toward Western Australia.  On its anticipated track Tropical Cyclone Yvette is expected to approach the coast of Western Australia in three or four days.

Tropical Cyclone Yvette could bring gusty winds and locally heavy rain when it makes landfall.  Yvette could also generate a storm surge near where the center makes landfall.

Tropical Cyclone Vardah Nears Somalia

Tropical Cyclone Vardah neared landfall in Somalia late on Sunday.  At 7:00 p.m. EST on Sunday the center of Tropical Cyclone Vardah was located at latitude 8.9°N and longitude 51.2°E which put it about 80 miles (130 km) east of Eyl, Somalia.  Vardah was moving toward the west at 17 m.p.h. (27 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. (70 km/h).  The minimum surface pressure was 1005 mb.

Tropical Cyclone Vardah has a small but well organized circulation.  A couple of rainbands wrap tightly near the center of circulation.  The are several other thin bands of showers.  Thunderstorms near the center are generating upper level divergence.  There is a distinct low level circulation, but it only extends about 120 miles (195 km) from the center.

Tropical Cyclone Vardah is being steering a little south of due west by a subtropical ridge north of the cyclone.  That general motion is expected to continue and Vardah could make landfall on the coast of Somalia in about 12 hours.  Tropical Cyclone Vardah could bring gusty winds and locally heavy rain where the center moves into Somalia.

Tropical Cyclone Vardah Moves Closer to Somalia

Tropical Cyclone Vardah moved closer to Somalia on Saturday.  At 7:00 p.m. EST on Saturday  the center of Tropical Cyclone Vardah was located at latitude 9.3°N and longitude 56.9°E which put it about 465 miles (745 km) east of Eyl, Somalia.  Vardah was moving toward the west-southwest at 18 m.p.h. (28 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. (70 km/h).  The minimum surface pressure was 1004 mb.

Tropical Cyclone Vardah has a small but well defined circulation.  Several rainbands wrap close to the center.  However, the rainbands are thin and thunderstorms are scattered along them.  It appears that the circulation is pulling in drier air from the surrounding environment.  The thunderstorms near the core of the circulation are generating some upper level divergence.

Environmental conditions around Tropical Cyclone Vardah contain both positive and negative factors.  Vardah is moving over water where the Sea Surface Temperature is near 27°C.  So, there is enough energy in the upper ocean to support intensification.  The winds in the upper levels are not very strong and there is little vertical wind shear.  Drier air seems to be the primary negative factor that is preventing intensification of Tropical Cyclone Vardah.  The drier air could prevent significant intensification of Vardah, but the low level circulation could be strong enough to persist for several more days.

A strong subtropical ridge north of Vardah is steering the tropical cyclone toward the west-southwest and that general motion is expected to continue for several more days.  On its anticipated track Tropical Storm Vardah could approach the coast of Somalia in a little over 24 hours.

Tropical Cyclone Vardah is small.  It could produce gusty winds when it reaches the coast.  Isolated areas could also receive locally heavy rain.

Tropical Cyclone Vardah Reorganizes Over the Arabian Sea

After moving across southern India and weakening Tropical Cyclone Vardah began to reorganize over the eastern Arabian Sea on Thursday.  At 7:00 p.m. EST on Thursday the center of Tropical Cyclone Vardah was located near latitude 11.0°N and longitude 68.0°E which put it about 1140 miles (1840 km) east of Baargaal, Somalia.  Vardah was moving toward the west at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 25 m.p.h. (40 km/h) and there were wind gusts to 35 m.p.h. (55 km/h).  The minimum surface pressure was 1007 mb.

Tropical Cyclone Vardah retained a well organized low level circulation as it moved across southern India and into the eastern Arabian Sea.  However, almost all of the showers and thunderstorms dissipated as the cyclone crossed over land.  A few showers and thunderstorms began to redevelop about 24 hours ago.  There are now several rainbands that are spiraling around the circulation and stronger thunderstorms are forming in some of those bands.  The thunderstorms are beginning to produce upper level divergence.

Tropical Cyclone Vardah will be moving through an environment that is favorable for intensification.  Vardah will be moving over water where the Sea Surface Temperature is near 28°C.  The upper level winds are weak and there is not much vertical wind shear.  Tropical Cyclone Vardah should continue to redevelop during the next 24 hours.

A subtropical ridge to the north of Vardah has been steering the tropical cyclone toward the west and that general motion is expected to continue.  On its anticipated track Tropical Cyclone Vardah will move across the Arabian Sea toward eastern Africa during the next several days.

Tropical Cyclone Vardah Moving Across Southern India

Tropical Cyclone Vardah made landfall near Chennai and moved westward across southern India on Monday.  At 8:00 p.m. EST on Monday the center of Tropical Cyclone Vardah was located at latitude 13.1°N and longitude 77.9°E which put it about 60 miles (100 km) east of Bangalore, India.  Vardah was moving toward the west at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1005 mb.

Tropical Cyclone Vardah was the equivalent of a hurricane when it made landfall and it brought strong winds and heavy rain to the area around Chennai, India.  Vardah weakened steadily after making landfall and most of the thunderstorms have weakened.  The spiral bands still contains scattered showers, but the winds have diminished.  The low level circulation is still well organized and there is a distinct center of low pressure at the surface.

A subtropical ridge to the north of Vardah continues to steer the tropical cyclone toward the west.  On its anticipated track Tropical Cyclone Vardah is expected to move over the Arabian Sea near Mangalore in about 24 hours.  Some numerical models are suggesting that Tropical Cyclone Vardah could reorganize after the center moves back over the water.

Tropical Cyclone Vardah Nearing Landfall in India

Tropical Cyclone Vardah moved steadily toward a landfall near Chennai India on Sunday.  At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Vardah was located at latitude 13.2°N and longitude 81.1°E which put it about 60 miles (105 km) east of Chennai, India.  Vardah was moving toward the west at 10 m.p.h. (16 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. (170 km/h).  The minimum surface pressure was 967 mb.

The Indian Meteorological Department’s radar at Chennai shows that Tropical Cyclone Vardah is very well organized and symmetrical.  There is a circular eye surrounded by a ring of strong thunderstorms.  The strongest storms are west and south of the eye, and the ring is thinner east of the eye.  There are multiple bands of thunderstorms and the heaviest thunderstorms in those bands are also in the western half of the circulation.  The thunderstorms are generating strong upper level divergence which is pumping out mass to the west and north of the tropical cyclone.

Tropical Cyclone Vardah is moving over water where the Sea Surface Temperature is near 29°C.  The energy from the ocean will keep Vardah from weakening before it makes landfall.  Tropical Cyclone Vardah will weaken steadily once it begins to move over southern India.

A subtropical ridge north of Vardah is steering the tropical cyclone toward the west and that general motion is expected to continue.  On its anticipated track Tropical Cyclone Vardah will make landfall near Chennai, India in a few hours.  Vardah will continue to move west across southern India after it moves inland.

Tropical Cyclone Vardah will bring strong winds and heavy rain to the area around Chennai.  The Hurricane Intensity Index (HII) is 12.7.  The Hurricane Size Index (HSI) is 11.3 and the Hurricane Wind Intensity Size Index (HWISI) is 24.0.  Those indices indicate that Tropical Cyclone Vardah is capable of causing regional minor wind damage when it makes landafall.

Vardah will also generate a storm surge along portion of the coast north of Chennai where the wind will blow the water toward the coast.  Vardah will produce locally heavy rain over Tamil Nadu, Andhra Pradesh and Karnataka.  The heavy rain could produce floods and mudslides.