Tag Archives: Laos

Tropical Storm Podul Drops Heavy Rain on Vietnam

Tropical Storm Podul dropped heavy rain on Vietnam on Thursday.  At 2:00 p.m. EDT on Thursday the center of Tropical Storm Podul was located at latitude 17.5°N and longitude 106.5°E which put it about 10 miles (15 km) northwest of Dong Hoi, Vietnam.  Podul was moving toward the west 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 994 mb.

Tropical Storm Podul made landfall near Dong Hoi, Vietnam on Thursday.  The structure of Podul was very asymmetrical.  Most of the thunderstorms were occurring in the western half of the circulation.  Tropical Storm Podul was moving south of an upper level ridge over eastern Asia.  The ridge was producing strong easterly winds which were blowing across the top of Podul.  Those winds were causing strong vertical wind shear and they were the reason why most of the thunderstorms were in the western half of the circulation.  As a result of the wind shear, heavy rain was already falling over Vietnam even before the center made landfall.

The upper level ridge was steering Tropical Storm Podul rapidly toward the west.  Podul will weaken quickly as it moves farther inland.  Even though Tropical Storm Podul will weaken quickly, heavy rain will fall over portions of Laos and northeastern Thailand on Friday.  Locally heavy rainfall could cause flash floods in parts of Vietnam, Laos and northeastern Thailand.

Tropical Storm Rumbia Makes Landfall Near Shanghai, Bebinca Hits Vietnam

Tropical Storm Rumbia made landfall on the east coast of China just south of Shanghai on Thursday, and Tropical Storm Babinca hit Vietnam.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Rumbia was located at latitude 30.5°N and longitude 121.0°E which put it about 60 miles (95 km) southwest of Shanghai, China.  Rumbia was moving toward the west at 14 m.p.h. (22 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.

Tropical Storm Rumbia strengthened before it made landfall.  Thunderstorms developed near the center of circulation and a band wrapped around the center.  The circulation became more circular and storms near the center began to generate upper level divergence.  In the western half off the circulation where the winds were blowing toward the land, increased friction enhanced rising motion and heavier rain fell.

Tropical Storm Rumbia caused some gusty winds near the coast, but the greater risks were the locally heavy rain and the potential for floods.  Tropical Storm Rumbia is forecast to move slightly north of due west as it moves inland over eastern China.  Rumbia will drop locally heavy rain over the area around Shanghai, and over parts Zhejiang, Jiangsu and Anhui provinces.  Some of those regions have received heavy rain from previous storms and the potential for serious flooding exists.

Tropical Storm Bebinca made landfall on the coast of Vietnam on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Bebinca was located at latitude 19.9°N and longitude 106.3°E which put it about 70 miles (110 km) southeast of Ninh Binh, Vietnam.  Bebinca was moving toward the west-southwest at 8 m.p.h. (13 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 979 mb.

Tropical Storm Bebinca also strengthened before it made landfall.  An eye started to form at the center of circulation and Bebinca was on the threshold of becoming a typhoon when it made landfall.  Tropical Storm Bebinca produced gusty winds and a storm surge near the coast.  However, the greatest risks are locally heavy rain and the potential for floods.  Tropical Storm Bebinca is forecast to move in a general westerly direction.  Bebinca will drop locally heavy rain over parts of Vietnam, northern Laos and extreme northern Thailand.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Soulik moved quickly toward Iwo To and strengthened.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Soulik was located at latitude 20.9°N and longitude 141.3°E which put it about 315 miles (510 km) south of Iwo To.  Soulik was moving toward the north at 20 m.p.h. (32 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 981 mb.

Tropical Storm Ampil Nears Landfall Southeast of Shanghai

Tropical Storm Ampil neared landfall on the coast of China southeast of Shanghai on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Ampil was located at latitude 31.0°N and longitude 122.3°E which put it about 60 miles (95 km) southeast of Shanghai, China.  Ampil was moving toward the west-northwest at 14 m.p.h. (22km/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 990 mb.

Tropical Storm Ampil moved steadily toward the coast of China on Saturday with little change of structure or intensity.  Drier air continued to circulate around the tropical storm and it limited the development of taller thunderstorms in much of Ampil.  The strongest thunderstorms were occurring in the inner portion of a band northwest of center of circulation.  The strongest winds were associated with those storms.  Bands around the rest of Tropical Storm Ampil consisted of showers and lower clouds.  Winds to tropical storm force extended out about 165 miles (270 km) from the center.

Tropical Storm Ampil will make landfall on the coast of China southeast of Shanghai in a few hours.  Ampil will cause gusty winds and the strong band of thunderstorms will drop locally heavy rain.  The heavy rain could cause flash floods in parts of eastern China.

Elsewhere the tropics became more active over the Western North Pacific Ocean on Saturday.  The remnants of former Tropical Storm Son-tinh were reorganizing west of Hainan Island over the Gulf of Tongking, Tropical Depression 13W moved east of Taiwan, and Tropical Depression 14W formed northwest of Wake Island and Tropical Depression 15W formed west of Guam.

At 11:00 p.m. EDT on Saturday the center of Tropical Depression Son-tinh was located at latitude 19.2°N and longitude 108.2°E which put it about 45 miles (75 km) west of Dongfeng, China.  Son-tinh was moving toward the east-southeast at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 999 mb.

Former Tropical Storm Son-tinh completed a slow clockwise loop over Laos and Vietnam which during the past several days and it emerged back over the Gulf of Tongking on Saturday.  There was a distinct low level center of circulation.  Bands of showers and thunderstorms were circulating around the enter.  The rainbands were dropping heavy rain over Hainan Island and creating the potential for flash floods.

At 11:00 p.m. EDT on Saturday the center of Tropical Depression 13W was located at latitude 21.6°N and longitude 122.9°E which put it about 165 miles (265 km) south-southeast of Hualien, Taiwan.  It was moving toward the northwest at 18 m.p.h. (29 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 998 mb.

At 11:00 p.m. EDT on Saturday the center of Tropical Depression 14W was located at latitude 22.5°N and longitude 159.4°E which put it about 370 miles (600 km) east-southeast of Minami Tori Shima.  It was moving toward the north 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 998 mb.

At 11:00 p.m. EDT on Saturday the center of Tropical Depression 15W was located at latitude 13.2°N and longitude 138.1°E which put it about 225 miles (365 km) north-northwest of Ulithi.  It was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 998 mb.

Tropical Storm Son-tinh Makes Landfall in Vietnam, Ampil Forms South of Okinawa

Tropical Storm Son-tinh made landfall in Vietnam on Wednesday while Tropical Storm Ampil formed south of Okinawa.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Son-tinh was located at latitude 19.1°N and longitude 105.5°E which put it about 30 miles (50 km) north-northwest of Vinh, Vietnam.  Son-tinh was moving toward the west at 14 m.p.h. (22 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 990 mb.

Tropical Storm Son-tinh strengthened on Wednesday after it moved away from Hainan Island.  A primary rainband wrapped around the western and southern side of the center of circulation and the inner end of the band began to evolve into a partial eyewall.  Thunderstorms in the core of Son-tinh generated upper level divergence which pumped away mass.  The removal of mass allowed the surface pressure to decrease.  A stronger pressure gradient force produced higher wind speeds.

Tropical Storm Son-tinh moved south of a ridge in the upper and middle troposphere.  The ridge steered Son-tinh steadily toward the west and the tropical storm made landfall just north of Vinh, Vietnam late on Wednesday.  Tropical Storm Son-tinh brought gusty winds and locally heavy rain to the coast of northern Vietnam around Vinh.  Son-tinh was also dropping locally heavy rain over portions of northern Vietnam and flash flooding could occur in some locations.

Tropical Storm Son-tinh will continue to move westward over northern Vietnam and northern Laos.  Son-tinh will weaken as the circulation moves inland.  It will continue to drop locally heavy rain and flash floods could occur in parts of northern Vietnam and northern Laos during the next several days.

The organization of former Tropical Depression 12W improved on Wednesday and the Japan Meteorological Agency designated the system as Tropical Storm Ampil.  At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Ampil was located at latitude 19.9°N and longitude 129.6°E which put it about 480 miles (775 km) south-southeast of Okinawa.  Ampil was moving toward the east-northeast 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 996 mb.

The circulation of Tropical Storm Ampil was not particularly well organized.  It exhibited characteristics of a hybrid low pressure system.  There was an upper low northwest of the low level circulation.  The upper low was causing strong southwesterly winds which were blowing across the top of the lower level circulation.  Those winds were causing significant vertical wind shear and they were tilting the circulation strongly toward the northeast.  The strongest bands of showers and thunderstorms were occurring south and west of the low level circulation.  Bands north and west of the center consisted primarily of showers and lower clouds.

The upper low will gradually move toward the west.  As the low moves westward, the vertical wind shear over Tropical Storm Ampil will start to decrease.  Ampil will move over water where the Sea Surface Temperature is near 29°C.  So, when the vertical wind shear decreases, then Tropical Storm Ampil will likely intensify.  Ampil could eventually strengthen into a typhoon in two or three days.

The upper low will initially will steer Tropical Storm Ampil toward the northeast.  When the upper low moves farther to the west on Thursday, then Ampil will move toward the north.  On its anticipated track the center of Tropical Storm Ampil could be near Okinawa and the Ryukyu Islands in two or three days.

Tropical Storm Son-tinh Moves Across Hainan Island

Tropical Storm Son-tinh moved across Hainan Island on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Son-tinh was located at latitude 18.9°N and longitude 108.5°E which put it about 15 miles (25 km) southwest of Dongfang, China.  Son-tinh was moving toward the west at 21 m.p.h. (34 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 center of Tropical Storm Son-tinh moved east to west across the southern half of Hainan Island on Tuesday.  In spite of moving over the island, the circulation of Tropical Storm Son-tinh retained its organization.  There was still a distinct low level center of circulation.  A primary rainband wrapped around the southern and eastern portions of the center.  Additional bands of showers and thunderstorms were revolving around the core of Son-tinh.  The strongest rainbands were in the western half of the tropical storm.  The circulation of Tropical Storm Son-tinh remains small.  Winds to tropical storm force only extend out about 70 miles (110 km) from the center of circulation.

Tropical Storm Son-tinh will move through an environment somewhat favorable for intensification during the next 12 hours.  Son-tinh will move over water where the Sea Surface Temperature is near 30°C.  It will move south of an upper level ridge.  The ridge will produce northeasterly winds which will blow toward the top of the circulation.  Those winds will create moderate vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Storm Son-tinh could strengthen after it moves west of Hainan Island and the center of circulation moves back over water.  Son-tinh is likely to reach the coast of Vietnam in 12 to 18 hours and it will weaken after landfall.

The ridge north of Son-tinh steered the tropical storm quickly toward the west on Tuesday.  It will continue to steer Tropical Storm Son-tinh in a general westerly direction on Wednesday.  On its anticipated track Tropical Storm Son-tinh will move steadily west of Hainan Island.  Locally heavy rain and gusty winds should gradually diminish there on Wednesday.  Son-tinh is likely to make landfall on the coast of Vietnam near Vinh in 12 to 18 hours and then move across Vietnam toward Laos.  Tropical Storm Son-tinh will bring gusty winds and locally heavy rain, but its impact will be lessened because of the small size of the circulation.  The heavy rain could cause flooding in isolated locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 12W formed east of Luzon.  At 11:00 p.m. EDT on Tuesday the center of Tropical Depression 12W was located at latitude 18.9°N and longitude 126.1°E which put it about 545 miles (875 km) south of Okinawa.  It was moving toward the west at 12 m.p.h.  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 999 mb.

Tropical Storm Son-tinh Develops East of Hainan Island

Tropical Storm Son-tinh developed east of Hainan Island on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Son-tinh was located at latitude 19.4°N and longitude 116.9°E which put it about 430 miles east of Hainan Island.  Son-tinh was moving toward the west at 24 m.p.h. (35 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 small circulation began west of Guam last week and then it moved north of the Philippines on Monday.  Thunderstorms would form near the circulation and then wind shear would blow the tops of the storms away.  A small area of thunderstorms eventually persisted near the center of circulation on Monday and the Japan Meteorological Agency designated the system as Tropical Storm Son-tinh.  There was a small tight center of circulation in Son-tinh, but strong upper level winds were causing the distribution of thunderstorms to be asymmetrical.  More of the thunderstorms were occurring west of the center.  The circulation of Son-tinh was relatively small.  Winds to tropical storm force only extended out 80 miles (130 km) from the center of circulation.

Tropical Storm Son-tinh will move through an environment marginally favorable for intensification.  Son-tinh will move over water where the Sea Surface Temperature is near 30°C.  Tropical Storm Son-tinh is moving south of an upper level ridge.  The ridge is producing strong easterly winds which are blowing toward the top of the circulation.  Those winds will cause strong vertical wind shear and the shear will limit intensification.  Tropical Storm Son-tinh could intensify a little before it reaches Hainan Island, but it will weaken when it moves over the island.

The ridge north of Son-tinh is steering the tropical storm rapidly toward the west and that general motion is forecast to continue on Tuesday.  On its anticipated track Tropical Storm Son-tinh will reach Hainan Island in about 18 hours.  Son-tinh will bring gusty winds and locally heavy rain.  Isolated flash floods could occur,but the overall impacts are likely to be minor.

Tropical Storm Bolaven Forms Over the South China Sea

Tropical Storm Bolaven formed over the South China Sea near the Spratly Islands on Tuesday.  At 10:00 p.m. EDT on Tuesday the center of Tropical Storm Bolaven was located at latitude 10.4°N and longitude 115.1°E which put it about 620 miles (1000 km) east of Ho Chi Minh City, Vietnam.  Bolaven was moving toward the west-northwest at 21 m.p.h. (33 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 1002 mb.

A low level center of circulation developed on the eastern side of a cluster of thunderstorms that moved across the southern Philippines on Monday.  The center exhibited greater organization on Tuesday and the Japan Meteorological Agency designated the system as Tropical Storm Bolaven.  The structure of Tropical Storm Bolaven is asymmetrical.  The strongest thunderstorms are occurring northwest of the center of circulation.  Thin bands of low clouds and showers were revolving around the center of circulation in the other quadrants of Tropical Storm Bolaven.

Tropical Storm Bolaven is moving around the southern side of an upper level ridge centered east of the Philippines.  The ridge is generating strong southeasterly winds which are blowing across the top of the circulation.  Those winds are causing moderate vertical wind shear.  The wind shear is probably the reason why most of the stronger storms are occurring northwest of the center of circulation.  Although Bolaven will move over water where the Sea Surface Temperature is near 28°C, the vertical wind shear will likely prevent intensification.  In fact if the shear increases, then Bolaven could weaken to a tropical depression.

The ridge north of Bolaven is steering the tropical storm toward the west-northwest and that general motion is expected to continue for several more days.  On its anticipated track Tropical Storm Bolaven could reach the coast of South Vietnam in 24 to 36 hours.  Bolaven will bring gusty winds and locally heavy rain to parts of southern Vietnam.

Tropical Depression Tembin Passes Near Southern Tip of Vietnam

The center of Tropical Depression Tembin passed near the southern tip of Vietnam on Monday night.  At 10:00 p.m. EST on Monday the center of Tropical Depression Tembin was located at latitude 8.5°N and longitude 104.6°E which put it about 200 miles (320 km) southwest of Ho Chi Minh City, Vietnam.  Tembin was moving toward the west at 14 m.p.h. (22 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 1005 mb.

An upper level ridge north of Tropical Depression Tembin continued to produce strong easterly winds which were blowing across the top of the circulation.  Those winds were causing strong vertical wind shear.  The shear was strong enough to prevent thunderstorm from developing in most parts of the circulation of Tropical Depression Tembin.  A few thunderstorms formed in the extreme northwestern portion of the circulation, but most of the circulation consisted of bands of low clouds and showers.  The strong shear and lack of tall thunderstorms caused the wind speeds at the surface to decrease and Tembin weakened to a tropical depression.

Tropical Depression Tembin will remain in an environment that is unfavorable for intensification.  Tembin 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 upper ridge will continue to produce strong easterly winds.  The vertical wind shear is likely to cause the circulation of Tropical Depression Tembin to spin down.

The ridge north of Tembin has been steering the tropical depression toward the west and a general westerly motion is expected to continue for another day or two.  On its anticipated track Tropical Depression Tembin will move across the Gulf of Thailand.   The center of Tropical Depression Tembin could reach the coast of Thailand near Sichon in about 36 hours.

Typhoon Tembin Nears Southern Vietnam

Typhoon Tembin moved nearer to southern Vietnam on Sunday.  At 10:00 p.m. EST on Sunday the center of Typhoon Tembin was located at latitude 8.0°N and longitude 109.3°E which put it about 290 miles (470 km) southeast of Ho Chi Minh City, Vietnam.  Tembin was moving toward the west at 13 m.p.h. (21 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 979 mb.

Typhoon Tembin weakened during the past 12 hours as it moved over the South China Sea.  An upper level ridge north of Tembin generated stronger easterly winds on Sunday which increased the vertical wind shear.  The strong upper level winds weakened the rainbands in the eastern half of the circulation of Typhoon Tembin.  Those winds also tilted the upper portion of the circulation toward the west.  The low level circulation of Typhoon Tembin remained well organized, but the storms around the center weakened.  The strongest thunderstorms were occurring in bands west of the core of Tembin.  Winds to typhoon force extended out about 40 miles (65 km) from the center in the northern half of the circulation and about 25 miles (40 km) in the southern half.  Winds to tropical storm force extended out about 155 miles (250 km) from the center.

Typhoon Tembin is likely to continue to weaken on Monday.  Typhoon Tembin will move over water where the Sea Surface Temperature is near 29°C.  However, the upper level ridge is likely to continue to generate strong easterly winds and the significant vertical wind shear will make it difficult for tall thunderstorms to develop around much of the circulation.  The wind shear will probably weaken Tembin to a tropical storm on Monday.

The ridge north of Tembin is steering the typhoon toward the west and a general westerly motion is expected to continue for several more days.  On its anticipated track the center of Typhoon Tembin will pass near the southern tip of Vietnam in about 24 hours.  Tembin will likely move into the Gulf of Thailand as a tropical storm or tropical depression.

The heavy rain with Typhoon Tembin is occurring in bands west of the core of the typhoon.  So, the heavy rain will begin to fall before the center of circulation reaches places.  The heaviest rain will fall over the Mouths of the Mekong River and the part of Vietnam south of that area.  The rain could be heavy enough to cause floods in some locations.  Gusty winds could produce isolated damage as well in the southern part of Vietnam.

Tembin Strengthens to a Typhoon Over South China Sea

Tropical Storm Tembin strengthened into a typhoon on Saturday as it moved over the South China Sea.  At 10:00 p.m. EST on Saturday the center of Typhoon Tembin was located at latitude 8.2°N and longitude 113.6°E which put it about 540 miles (880 km) east of Ho Chi Minh City, Vietnam.  Tembin was moving toward the west at 18 m.p.h. (29 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 976 mb.

Typhoon Tembin became much better organized on Saturday.  A primary rainband wrapped around the center of circulation and an eye became apparent on microwave satellite imagery.  Several other rainbands strengthened outside the core of Typhoon Tembin.  Storms near the core of the circulation generated strong upper level divergence which pumped mass away to the west and northeast of the typhoon.  The removal of mass allowed the surface pressure to decrease and the wind speed to increase.  Winds to typhoon force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 155 miles (250 km) from the center.

Typhoon Tembin will move through an environment favorable for intensification during the next 24 hours.  Tembin will move over water where the Sea Surface Temperature is near 29°C.  An upper level ridge north of Tempin is producing easterly winds which are blowing toward the typhoon.  However, the easterly winds are blowing at most levels of the atmosphere and there is not a lot of vertical wind shear.  Typhoon Tembin is likely to continue to intensify on Sunday.

The subtropical ridge north of Tembin is steering the typhoon quickly toward the west.  A general motion toward the west is expected to continue.  On its anticipated track Typhoon Tembin could approach the southern part of Vietnam in about 36 hours.  Tembin has the potential to bring strong winds, heavy rain and a storm surge to the southern coast of Vietnam.