Tag Archives: 13W

Tropical Storm Noul Brings Wind and Rain to Central Vietnam

Tropical Storm Noul brought wind and rain to central Vietnam on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Noul was located at latitude 16.7°N and longitude 107.2°E which put it about 45 miles (75 km) north-northwest of Da Nang, Vietnam.  Noul was moving toward the west at 22 m.p.h. (35 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 994 mb.

The distribution of thunderstorms and rain around Tropical Storm Noul was asymmetrical.  The strongest thunderstorms and the heaviest rain were on the western side of Noul.  Tropical Storm Noul was moving under the southern part of a large upper level ridge over Asia and the Western North Pacific Ocean.  The ridge was producing strong easterly winds which were blowing toward the top of Noul.  Those winds were causing moderate vertical wind shear and they were also the cause of the asymmetrical distribution of rainfall.  Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation.

The upper level ridge will steer Tropical Storm Noul quickly toward the west.  Noul will across central Vietnam and southern Laos on Friday.  Tropical Storm Noul will drop locally heavy rain over parts of central Vietnam, southern Laos and northeastern Thailand.  Flash floods could occur in some locations.

Tropical Storm Noul Moves Toward Vietnam

Tropical Storm Noul moved toward Vietnam on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Noul was located at latitude 14.8°N and longitude 113.8°E which put it about 420 miles (675 km) east-southeast of Da Nang, Vietnam.  Noul was moving toward the northwest at 12 m.p.h. (19 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 994 mb.

Tropical Storm Noul moved under the southern portion of a large upper level ridge over Asia and the Western North Pacific Ocean.  The ridge produced strong easterly winds which blew toward the top of Noul’s circulation.  Those winds caused moderate vertical wind shear and they contributed to an asymmetrical distribution of thunderstorms in Tropical Storm Noul.  The strongest thunderstorms were occurring in the western half of Noul.  Bands in the eastern half of the circulation consisted primarily of showers and lower clouds.  Storms near the center of circulation generated upper level divergence which pumped mass away to the west of the tropical storm.  Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation.

Tropical Storm Noul will move through an environment marginally favorable for intensification during the next 24 hours.  Noul will move over water where the Sea Surface Temperature is near 30.5°C.  The upper level ridge will continue to cause moderate vertical wind shear.  The shear will inhibit intensification.  Tropical Storm Noul could strengthen if the wind shear decreases.

The upper level ridge will steer Tropical Storm Noul toward the west-north west during the next day or so.  On its anticipated track Noul will approach the coast of central Vietnam in about 24 hours.  Tropical Storm Noul will bring gusty winds and rain to central Vietnam on Friday.

Tropical Storm Noul Forms West of the Philippines

Tropical Storm Noul formed over the South China Sea west of the Philippines on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Noul was located at latitude 12.9°N and longitude 118.0°E which put it about 215 miles (345 km) southwest of Manila, Philippines.  Noul was moving toward the west-northwest 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 1000 mb.

The circulation around Tropical Storm Noul was still organizing on Tuesday afternoon.  More thunderstorms were developing near the center of circulation.  Bands of showers and thunderstorms were revolving around the center of Noul.  Storms near the center started to generate upper level divergence which pumped mass away to the west of the tropical storm.  Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation.

Tropical Storm Noul will move through an environment favorable for intensification during the next 48 hours.  Noul will move over water where the Sea Surface Temperature is near 30.5°C.  It will move south of an upper level ridge over the South China Sea.  The ridge will produce easterly winds which will blow toward the top of Tropical Storm Noul.  Those winds will cause moderate vertical wind shear, but they will not be strong enough to prevent Noul from intensifying.  Tropical Storm Noul could strengthen into a typhoon within 48 hours.

Tropical Storm Noul will move south of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer Noul toward the west-northwest during the next several days.  On its anticipated track Noul could approach the coast of Vietnam in about 60 hours.  It is likely to be a typhoon when it nears Vietnam.

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 Podul Forms East of Luzon

Tropical Storm Podul formed east of Luzon on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Podul was located at latitude 15.1°N and longitude 125.2°E which put it about 250 miles (400 km) east of Baler, Philippines.  Podul was moving a little to the north of due west at 25 m.p.h. (40 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.

A low level center of circulation in an area of thunderstorms east of Luzon was visible in satellite imagery on Monday night and the Japan Meteorological Agency designated the system as Tropical Storm Podul.  The circulation around Tropical Storm Podul was not well organized.  Many of the thunderstorms were occurring in broken bands west of the center of circulation.  Bands in the eastern half of Podul consisted primarily showers and lower clouds.  Tropical Storm Podul was moving south of an upper level ridge over eastern Asia and the Western North Pacific Ocean.  The ridge was producing easterly winds which were causing moderate vertical wind shear.  The shear was contributing to the poorly organized circulation around Podul.

Tropical Storm Podul will move through an environment mostly unfavorable for intensification during the next 24 hours,  Podul will move over water where the Sea Surface Temperature is near 29°C.  However, the upper level ridge will continue to cause moderate vertical wind shear.  The center will move across northern Luzon and increased friction will weaken the circulation.  Tropical Storm Podul could weaken to a tropical depression when it crosses Luzon.  Podul could strengthen in the middle of the week when it moves west of Luzon and out over the South China Sea.

Tropical Storm Podul will move south of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Podul a little to the north of due west during the next few days.  On its anticipated track Tropical Storm Podul will move across northern Luzon on Tuesday. Podul will cause gusty winds and locally heavy rain.  The rain could cause flash floods in some locations.  Tropical Storm Podul will move west of Luzon and over the South China Sea in about 24 hours.  Podul could approach Hainan Island in about 72 hours.

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 Ampil Moves Over Okinawa

Tropical Storm Ampil moved over Okinawa on Friday night.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Ampil was located at latitude 27.3°N and longitude 127.4°E which put it about 25 miles (40 km) north-northwest of Okinawa.  Ampil was moving toward the northwest at 21 m.p.h. (34 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 990 mb.

Drier air continued to circulated around Tropical Storm Ampil on Friday and the drier air prevented Ampil from intensifying.  Several bands of stronger thunderstorms were occurring northeast of the center of circulation and the strongest winds were occurring in those bands.  The bands in other parts of Tropical Storm Ampil consisted primarily of the showers and low clouds.  There was a distinct low level center of circulation, but there were few thunderstorms near the center.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Tropical Storm Ampil is unlikely to intensify significantly before it makes landfall in China.  Ampil will move over water where the Sea Surface Temperature is near 28°C.  So, there will be enough energy in the ocean to support intensification.  There is a chance for some intensification on Saturday, if more thunderstorms develop near the center of circulation.  However, the drier air will inhibit the formation of taller thunderstorms and that will limit possible intensification..

Tropical Storm Ampil will move south of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Ampil quickly toward the northwest.  On its anticipated track Tropical Storm Ampil will move quickly away from Okinawa and the Ryukyu Islands.  Ampil could approach the coast of China near Shanghai in about 24 hours.  Tropical Storm Ampil will bring gusty winds and locally heavy rain to the region of China around Shanghai.

Elsewhere over the Western North Pacific Ocean Tropical Depression 13W formed west of northern Luzon.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 13W was located at latitude 18.0°N and longitude 118.9°E which put it about 140 miles (225 km) west of Laoag, Philippines.  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.  The depression could bring locally heavy rain and cause flash floods over Luzon during the weekend.

Tropical Storms Lionrock and Kompasu Spin Up Near Japan

A large cyclonic atmospheric gyre near Japan spun up two more tropical storms at the end of the week.  The Japan Meteorological Agency named two smaller circulations within the larger gyre Tropical Storm Lionrock and Tropical Storm Kompasu.

At 2:00 p.m. EDT on Saturday the center of Tropical Storm Kompasu was located at latitude 37.8°N and longitude 142.3°E which put it about 75 miles (120 km) east of Sendai, Japan.  Kompasu was moving toward the northwest at 26 m.p.h. (42 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.

At 2:00 p.m. EDT on Saturday the center of Tropical Storm Lionrock was located at latitude 30.6°N and longitude 135.7°E which put it about 530 miles (860 km) east-northeast of Okinawa.  Lionrock was moving toward the west-southwest 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 994 mb.

Tropical Storm Kompasu is located farther north and it is beginning to make a transition into an extratropical cyclone.  Kompasu is moving over water where the Sea Surface Temperature (SST) is near 26°C, but it is moving rapidly toward cooler SSTs.  Most of the thunderstorms are in a single primary rainband that wraps around the southern part of the circulation.  An upper level trough west of Japan is pulling southwesterly winds across the top of Tropical Storm Kompasu and the vertical wind shear is increasing.

The upper level trough is expected to turn Tropical Storm Kompasu toward the northeast.  On its anticipated track Tropical Storm Kompasu will move across Hokkaido in about 18 hours.  It will bring locally heavy rain and some wind.

Tropical Storm Lionrock is more well organized.  Several spiral bands of thunderstorms are wrapping around the southern and east sides of the center of circulation.  There is drier air in the western portion of the circulation and there are few thunderstorms in that part of Lionrock.  The thunderstorms east of the center are generating upper level divergence that is pumping mass toward the northeast away from core of Tropical Storm Lionrock.

Tropical Storm Lionrock is in an environment that is somewhat favorable for additional intensification.  It is moving over water where the SST is near 30°C.  The upper level trough west of Japan is generating some vertical wind shear.  The drier air in the western part of the circulation will also inhibit intensification, but Lionrock could gradually get better organized.  Upper level outflow from stronger Tropical Storm Mindulle, which is southwest of Lionrock, could produce enough vertical wind shear to weaken Lionrock at times.

The large atmospheric gyre is steering Tropical Storm Lionrock toward the west-southwest.  Lionrock could be pulled more toward the south as the larger, stronger Tropical Storm Mindulle passes east of it.  Tropical Storm Lionrock is expected to remain south of Japan during the next several days.  An alternative scenario would be for Tropical Storm Mindulle to intensify into a typhoon and grow large enough to absorb the circulation of Lionrock.