Tag Archives: 06W

Tropical Storm Danas Nears Southern Ryukyu Islands

Tropical Storm Danas moved near the southern Ryukyu Islands late on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Danas was located at latitude 23.9°N and longitude 124.1°E which put it about 30 miles (50 km) south of Ishigaki, Japan.  Danas was moving toward the north at 21 m.p.h. (34 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 990 mb.

The circulation around Tropical Storm Danas exhibited a little more organization on Wednesday.  More thunderstorms formed near the center of circulation and several bands of showers and thunderstorms formed in the eastern half of the circulation.  The bands north and west of the center consisted primarily of showers and lower clouds.  Storms near the center began to generate upper level divergence which pumped mass away to the northeast of the tropical storm.  Winds to tropical storm force extended out about 125 miles (200 km) from the center of circulation.

Tropical Storm Danas will move into an environment somewhat favorable for intensification.  Danas will move over water where the Sea Surface Temperature is near 30°C.  A small upper level low near Taiwan will produce southwesterly winds which blow toward the top of the circulation around Tropical Storm Danas.  Those winds were the reason why the stronger rainbands were in the eastern half of the circulation.  Those winds will cause moderate vertical wind shear, which will inhibit intensification.  However, the shear will have less of an effect since Danas will move in the same direction as the upper level winds.  Tropical Storm Danas is likely to intensify during the next 24 hours and there is a chance it could strengthen into a typhoon.

Tropical Storm Danas will move around the western end of a subtropical ridge over the western North Pacific Ocean.  The ridge will steer Danas toward the north-northeast.  On its anticipated track Tropical Storm Danas will move through the southern Ryukyu Islands during the next few hours.  Danas will bring gusty winds and locally heavy rain when it passes over those islands.  Tropical Storm Danas will move over the East China Sea toward southwestern Japan and South Korea during the next several days.

Tropical Storm Danas Forms East of Luzon

Tropical Storm Danas formed east of Luzon on Tuesday.  A distinct low level center of circulation developed in an area of low pressure east of Luzon and the Japan Meteorological Agency designated the system as Tropical Storm Danas.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Danas was located at latitude 17.5°N and longitude 123.1°E which put it about 80 miles (130 km) east of Tuguegarao, Philippines.  Danas was moving toward the west at 4 m.p.h. (6 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 994 mb.

The distribution of thunderstorms around Tropical Storm Danas was highly asymmetrical.  There were a few thunderstorms just to the southwest of the center of circulation, but most of the thunderstorms were occurring in a band on the far western edge of the circulation around Danas.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  Tropical Storm Danas was moving around the southeastern portion of an upper level ridge over east Asia.  The ridge was producing strong easterly winds which were blowing across the top of the circulation around Danas.  The easterly winds were causing strong vertical wind shear and the wind shear was causing the asymmetric distribution of thunderstorms.  The circulation around Tropical Storm Danas was large.  Winds to tropical storm force extended out about 200 miles (320 km) from the center of circulation.

Tropical Storm Danas will move into an environment that is only marginally favorable for intensification.  Danas will move over water where the Sea Surface Temperature is near 31°C.  So, there is plenty of energy in the upper ocean.  The strong upper level easterly winds are expected to weaken somewhat during the next several days.  If those winds weaken, then there will be less vertical wind shear and Tropical Storm Danas could strengthen.  If the upper level winds remain strong, then Danas will not strengthen and it could weaken to a tropical depression.  The forecast is for very slow intensification during the next 24 to 48 hours.

Since there are not a lot of taller thunderstorms near the center of Tropical Storm Danas, it will be steered by the winds in the lower troposphere.  Danas will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will turn Danas toward the north on Wednesday.  On its anticipated track the center of Tropical Storm Danas will remain east of Luzon.  The center of Danas could be near southeastern Taiwan in 24 to 36 hours.  Tropical Storm Danas could be near the east coast of China in about three days.  The primary risks will be locally heavy rain and flash floods.

Maliksi Strengthens Into a Typhoon East of Okinawa

Former Tropical Storm Maliksi strengthened into a typhoon east of Okinawa near Minami Daito Jima late on Saturday.  At 11:00 p.m. EDT on Saturday the center of Typhoon Maliksi was located at latitude 25.7°N and longitude 131.7°E which put it about 210 miles (335 km) east of Okinawa.  Maliksi was moving toward the northeast at 24 m.p.h. (39 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 970 mb.

The circulation of Typhoon Maliksi became more organized on Saturday.  An inner rainband wrapped around the center of circulation and an eye was apparent on satellite images.  There were intermittent breaks in the rings of thunderstorms around the eye.  Several bands of showers and thunderstorms in the eastern half of the circulation were revolving around the core of the typhoon.  Bands west of the center consisted primarily of showers and low clouds.  Storms near the core of Maliksi were generating upper level divergence which was pumping mass away to the northeast of the typhoon.  The circulation of Typhoon Maliksi was large and winds to tropical storm force extended out about 250 miles (400 km) from the center of circulation.

Typhoon Maliksi will move through an environment favorable for intensification during the next 12 to 24 hours.  Maliksi will move over water where the Sea Surface Temperature is near 30°C.  An upper level trough to the west of Maliksi will produce southwesterly winds which will blow toward the top of the circulation.  Those winds will produce some vertical wind shear, but the shear will not be strong enough to prevent intensification on Sunday.  The shear will increase after 18 to 24 hours and that will likely cause Maliksi to start to weaken.

The upper level trough is steering Maliksi toward the northeast and that general motion is expected to continue for another two or three days.  Typhoon Maliksi will speed past Minami Daito Jima during the next few hours.  On its anticipated track Maliksi will reach some of the islands south of Honshu in about 24 hours.  Typhoon Maliksi will produce gusty winds and locally heavy rain.

Tropical Storm Maliksi Forms East of Luzon, Ewiniar Brings Rain to South China.

Tropical Storm Maliksi formed east of Luzon on Thursday while Tropical Storm Ewiniar brought rain to parts of South China.  At 8:00 p.m. EDT on Thursday the center of Tropical Storm Maliksi was located at latitude 17.4°N and longitude 127.7°E which put it about 330 miles (535 km) east of Luzon.  Maliksi was moving toward the north at 4 m.p.h. (6 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 996 mb.

The Japan Meteorological Agency designated an area of low pressure east of Luzon as Tropical Storm Maliksi late on Thursday.  There was a large counterclockwise circulation east of Luzon, but there were few thunderstorms near the center of the circulation.  Most of the thunderstorms were occurring in three bands in the outer portions of the circulation.  One band was located well to the west of the center of circulation, a second band was located well to the north of the center and the third band was located well to the east of the center.  The winds to tropical storm force were occurring in those bands.

Tropical Storm Maliksi will move through an environment favorable for intensification during the next 24 to 48 hours.  Maliksi will move over water where the Sea Surface Temperature is near 30°C.  Maliksi will move underneath an upper level ridge where the winds are weak and there will be little vertical wind shear.  The large circulation will be the primary factor inhibiting intensification in the short term.  Maliksi will intensify slowly until thunderstorms develop near the center of circulation and the strongest winds occur closer to the center.

Tropical Storm Maliksi will move around the western end of a subtropical ridge.  The ridge will steer Maliksi slowly toward the north.  When Tropical Storm Maliksi moves farther to the north westerly winds will begin to steer it toward the northeast.  On its anticipated track Tropical Storm Maliksi will remain east of Luzon.  The circulation of Maliksi is so large that rainbands on the western side of the circulation could affect the northern Philippines.

Elsewhere over the western North Pacific Ocean, Tropical Storm Ewiniar brought heavy rain to parts of South China.  Ewiniar made landfall on the coast of China near Yangjiang on Thursday.  At 8:00 p.m. EDT on Thursday the center of Tropical Storm Ewiniar was located at latitude 22.6°N and longitude 112.1°E which put it about 50 miles (80 km) northeast of Yangjiang, China.  Ewiniar was moving toward the north at 9 m.p.h. (15 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 998 mb.

The center of Tropical Storm Ewiniar was moving farther inland over South China.  The winds to tropical storm force were occurring in rainbands that were still over the South China Sea.  Ewiniar was dropping heavy rain over parts of western Guangdong province and over southern Zizhiqu province.  The heavy rain could cause flooding in those areas.

Tropical Storm Talas Makes Landfall in Vietnam

Tropical Storm Talas made landfall on the coast of Vietnam on Sunday.  Talas was bringing gusty winds and heavy rainfall to parts of Vietnam, Laos and Thailand.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Talas was located at latitude18.6°N and longitude 105.5°E which put the center near Vinh, Vietnam.  Talas was moving toward the west at 17 m.p.h. (27 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 984 mb.

Tropical Storm Talas strengthened before it made landfall in Vietnam.  A primary band wrapped around the western and southern sides of the center of circulation.  Thunderstorms formed near the center of Talas as the tropical storm approached the coast of Vietnam.  The strongest winds in Tropical Storm Talas were occurring in thunderstorms over the South China Sea.  Tropical Storm Talas will weaken as it moves farther inland.

Tropical Storm Talas was bringing gusty winds and heavy rain to parts of Vietnam, Laos and Thailand.  Locally heavy rain could cause flooding, which will be the greatest risk as Tropical Storm Talas moves farther inland.

Tropical Storm Talas Forms East of Vietnam

Tropical Storm Talas formed east of Vietnam on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Talas was located at latitude 17.3°N and longitude 110.1°E which put it about 170 miles (270 km) east-northeast of Da Nang, Vietnam.  Talas was moving toward the west at 11 m.p.h. (17 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 996 mb.

A large area of showers and thunderstorms persisted over the South China Sea for the past several days.  A distinct center of circulation began to develop in the northern part of the area of thunderstorms.  The Japan Meteorological Agency classified the system as Tropical Storm Talas on Saturday.

The circulation of Tropical Storm Talas is still organizing.  The center of rotation was near the northwestern edge of the area of thunderstorms.  Additional thunderstorms were beginning to form near the center of circulation.  Several bands of showers and thunderstorms were southwest of the center.  Bands of lighter showers were occurring in the remainder of Tropical Storm Talas.  Thunderstorms forming near the center of circulation were beginning to generate strong upper level divergence which was pumping out mass.

Tropical Storm Talas has about 24 hours to strengthen.  Talas will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge north of Talas is producing easterly winds which are blowing toward the top of the tropical storm.  There is some vertical wind shear, but the shear appears to have diminished during the past few hours.  Since Tropical Storm Talas will be moving through an environment of very warm water and reduced vertical wind shear, it will likely strengthen during the next 24 hours.

A subtropical ridge north of Talas is steering the tropical storm toward the west and motion a little to the north of due west is forecast.  On its anticipated track the center of Tropical Storm Talas will pass south of Hainan Island.  Tropical Storm Talas will approach the coast of Vietnam near Vinh in about 24 hours.  Tropical Storm Talas will bring gusty winds and locally heavy rain to Central Vietnam when it makes landfall.

Typhoon Nida Makes Landfall Near Hong Kong

Typhoon Nida made landfall on Monday near Hong Kong on the coast of China.  At 5:00 p.m. EDT on Monday the center of Typhoon Nida was located at latitude 22.8°N and longitude 114.4°E which put it about 50 miles (80 km) east-northeast of Hong Kong.  Nida was moving toward the northwest t 13 m.p.h.  The maximum sustained wind speed was 95 m.p.h. (155 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 963 mb.

Typhoon Nida made landfall on the southeast coast of China just to the north of Hong Kong.  The core of Nida is large and the typhoon is capable of causing wind damage on a regional scale.  Wind blowing toward the coast could also generate a storm surge until Typhoon Nida moves farther inland.  However, very heavy rain and fresh water flooding are much greater risks as Nida moves farther inland over China.

A subtropical ridge north of Nida is steering the typhoon toward the northwest and that general motion is expected to continue for the next several days.  The ridge will steer Nida farther inland over southeastern China.  Typhoon Nida’s fairly slow motion and large size mean that heavy rain could fall over an expansive area.  The risk for flooding will continue as Nida moves inland.

Typhoon Nida Brushes Luzon and Heads for Hong Kong

Typhoon Nida brought wind and rain to northern Luzon on Sunday as it continued to move toward Hong Kong on the coast of China.  At 11:00 p.m. EDT on Sunday the center of Typhoon Nida was located at latitude 20.4°N and longitude 118.3°E which put it about 340 miles (545 km) east-southeast of Hong Kong.  Nida was moving toward the west-northwest at 17 m.p.h. (27 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 Hurricane Intensity Index (HII) for Typhoon Nida is 10.4.  The Hurricane Size Index (HSI) is 13.1 and the Hurricane Wind Intensity Size Index (HWISI) is 23.5.  These indices suggest that Typhoon Nida will be capable of causing minor wind damage on a regional scale.

The structure of Typhoon Nida changed significantly on Sunday.  The primary rainband wrapped around the core of the circulation and a very large eye was created at the center.  The diameter of the eye is approximately 50 miles (80 km).  The strongest winds are occurring in the ring of thunderstorms that surrounds the eye.  Other spiral bands of thunderstorms are rotating around the large eye.  The thunderstorms were generating upper level divergence which pumped out mass and allowed the surface pressure to decrease.

Typhoon Nida is in an environment that would favor intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  Easterly winds are blowing in the upper levels, but there is not much vertical wind shear.  The large size of the eye of Nida is the major factor inhibiting intensification.  It takes more energy to increase the wind speed in a large typhoon than it does in a smaller storm.  If the eye contracts, then Typhoon Nida could intensify more before it makes landfall.

A subtropical ridge north of Nida is steering the typhoon toward the west-northwest and that general motion is expected to continue for another day or so.  On its anticipated track Typhoon Nida will be very near Hong Kong in about 24 hours.

As mentioned above, the large size of Typhoon Nida means that it will be capable of causing wind damage on a regional scale.  In addition, Typhoon Nida will be capable of creating a significant storm surge when it moves into the coast of China.  A large slow moving typhoon like Nida will also produce heavy rain and flooding as it moves inland.

Intensifying Tropical Storm Nida Nears Northern Philippines

Tropical Storm Nida intensified on Saturday as it slowly approached the northern portion of Luzon in the Philippines.  At 5:00 p.m. EDT (2100 UTC) the center of of Tropical Storm Nida was located at latitude 16.5°N and longitude 123.8°E which put it about 245 miles (395 km) east-northeast of Manila, Philippines.  Nida was moving toward the west-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 50 m.p.h. (95 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 989 mb.

The circulation of Tropical Storm Nida has become increasingly well organized during the past 24 hours.  A primary rainband wraps about two thirds of the way around the western and southern sides of the center of circulation.  Additional spiral bands of thunderstorms are developing outside the core of the circulation.  Rising motion associated with the convection is generating upper level divergence which is pumping out mass and allowing the surface pressure to decrease.

Tropical Storm Nida is moving through an environment that is very favorable for further intensification.  It is moving over water where the Sea Surface Temperature (SST) is near 31°C.  Nida is beneath an upper level ridge where the upper level winds are light and there is little vertical wind shear.  Very warm SSTs and little wind shear will allow the circulation of Tropical Storm Nida to consolidate further and it should continue to intensify.  Nida could intensify rapidly once an eye starts to form at the center of circulation.  Tropical Storm Nida will move near or over the northeastern part of Luzon.  Interaction with land could slow or temporarily stop the intensification.  However, Tropical Storm Nida should intensify further after it move wests of the Philippines.

A subtropical ridge north of Nida is steering the tropical storm toward the west-northwest and that general motion is expected to continue.  On its anticipated track Tropical Storm Nida could move over the northern part of Luzon during the next 12 to 24 hours.  Nida could approach the area around Hong Kong as a typhoon in about 48 hours.

The primary threats posed by Tropical Storm Nida to the Philippines are locally heavy rain and flash floods.  Tropical Storm Nida could generate very heavy rain in locations where the circulation causes the wind to blow up the slopes of mountains.  Heavy rain falling on steep terrain in those locations could also cause flash flooding.  Nida could be a typhoon by the time it reaches the part of China near Hong Kong.  Nida will be capable of producing some wind damage and storm surge in addition to heavy rain and flooding when it reaches the coast of China.