Tag Archives: Okinawa

Typhoon Mangkhut Strengthens to Equivalent of a Major Hurricane

Typhoon Mangkhut strengthened into the equivalent of a major hurricane as it moved west of Guam on Monday.  At 11:00 p.m. EDT on Monday the center of Typhoon Mangkhut was located at latitude 14.0°N and longitude 140.6°E which put it about 230 miles (375 km) west of Guam.  Mangkhut was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (270 km/h).  The minimum surface pressure was 939 mb.  Typhoon Mangkhut was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.

Typhoon Mangkhut intensified rapidly on Monday.  A circular eye was at the center of circulation.  A ring of strong 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 Typhoon Mangkhut.  Storms around the core were generating upper level divergence which was pumping mass away from the typhoon.

Winds to typhoon force extended out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Mangkhut was 28.2.  The Hurricane Size Index (HSI) was 18.9 and the Hurricane Wind Intensity Size Index (HWISI) was 47.1.

Typhoon Mangkhut will move through an environment capable of supporting very strong typhoons during the next two or three days.  Mangkhut will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Mangkhut is likely to remain very strong for the next few days.  Eyewall replacement cycles could cause fluctuations in intensity.

Typhoon Mangkhut will move south of a ridge over the Western North Pacific Ocean.  The ridge will steer Mangkhut to the west during the next day or two.  Typhoon Mangkhut will move more toward the west-northwest later this week.  On its anticipated track Typhoon Mangkhut could be near northern Luzon in about four days.

Typhoon Mangkhut Brings Wind and Rain to the Marianas

Typhoon Mangkhut brought wind and rain to the Marianas on Sunday night.  At 11:00 p.m. EDT on Sunday the center of Typhoon Mangkhut was located at latitude 14.4°N and longitude 146.6°E which put it about 175 miles (285 km) east-northeast of Guam.  Mangkhut was moving toward the west at 19 m.p.h. (31 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 955 mb.  Typhoon Warnings were in effect for Saipan, Tinian, Rota and Guam.  The airport on Saipan was reporting sustained winds of 41 m.p.h. (66 km/h) and wind gusts to 61 m.p.h. (98 km/h).

Typhoon Mangkhut had a well organized circulation.  There was a circular eye at the center of Mangkhut.  A ring of strong 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 Typhoon Mangkhut.  Storms near the core were generating upper level divergence which was pumping mass away from the typhoon.

Winds to 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 Typhoon Mangkhut was 13.9.  The Hurricane Size Index (HSI) was 13.5 and the Hurricane Wind Intensity Size Index was 27.4.  Typhoon Mangkhut was capable of causing regional significant damage.

Typhoon Mangkhut will move through an environment favorable for intensification.  Mangkhut will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge north of Mangkhut will cause 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.  Typhoon Mangkhut could intensify into the equivalent of a major hurricane later this week.

The ridge north of Typhoon Mangkhut will steer the typhoon in a westerly direction.  The core of Typhoon Mangkhut will move over the Marianas during the next few hours.  It will bring strong winds and it will drop locally heavy rain.  On its anticipated track Typhoon Mangkhut could be east of Luzon later this week.

Tropical Storm Mangkhut Causes Typhoon Watch for Marianas

Tropical Storm Mangkhut caused a Typhoon Watch to be issued for the Marianas on Saturday.  A Typhoon Watch was in effect for Guam, Rota, Saipan and Tinian.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Mangkhut was located at latitude 14.9°N and longitude 156.0°E which put it about 760 miles (1225 km) east of Guam.  Mangkhut was moving toward the west at 24 m.p.h. (39 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 983 mb.

The circulation of Tropical Storm Mangkhut became much better organized on Saturday despite its rapid westward movement.  A primary band of thunderstorms wrapped around the southern side of the center of circulation and an eye appeared to be forming.  Winds near the core of Mangkhut were generating upper level divergence which was pumping mass away from the tropical storm.  Several other bands of showers and thunderstorms were revolving around the core of Tropical Storm Mangkhut.  The strongest rainbands were in the western half of the circulation.  Bands in the eastern half of the tropical storm consisted primarily of showers and lower clouds.  An upper level ridge north of Mangkhut was producing easterly winds which were blowing toward the top of the circulation.  Those winds were causing vertical wind shear and they were probably the reason why the strongest rainbands were west of the center of circulation.

Tropical Storm Mangkhut will move through an environment favorable for intensification.  Mangkhut will move over water where the Sea Surface Temperature is near 30°C.  It will move into an area where the upper level winds are weaker and there will be less vertical wind shear.  Tropical Storm Mangkhut will intensify into a typhoon on Sunday and it could intensify rapidly once the inner core and eye are fully formed.

Tropical Storm Mangkhut will move south of a ridge over the Western North Pacific Ocean.  The ridge will steer Mangkhut in a general westerly direction during the next few days.  On its anticipated track Tropical Storm Mangkhut could reach the Marianas in about 36 hours.  It is likely to be a typhoon at that time.  Mangkhut could bring strong winds and locally heavy rain to Guam, Rota, Saipan and Tinian.

Tropical Storm Cimaron Prompts Warnings for Northern Marianas, Soulik Strengthens West of Iwo To

Tropical Storm Cimaron developed east of the Northern Marianas on Saturday and it prompted Typhoon Warnings for some of the islands, while Typhoon Soulik strengthened west of Iwo To.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Cimaron was located at latitude 15.5°N and longitude 151.6°E which put it about 420 miles (675 km) east of Saipan.  Cimaron was moving toward the northwest at 8 m.p.h. (13 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 997 mb.  A Typhoon Warning was in effect for Agrihan, Pagan and Almagan.

A distinct center of circulation developed in an area of thunderstorms east of the Northern Marianas on Saturday and the Japan Meteorological Agency designated the system as Tropical Storm Cimaron.  Numerous bands of showers and thunderstorms developed around the circulation of Tropical Storm Cimaron.  The rainbands west and south of the center of circulation were stronger than the bands east and north of the center.  An inner bands of thunderstorms started to wrap around the south side of the center.  Storms near the center began to generate upper level divergence.

Tropical Storm Cimaron will move through an environment favorable for intensification during the next several days.  Cimaron will move over water where the Sea Surface Temperature is near 29°C.  Tropical Storm Cimaron will move through an area where it will be near the upper level divergence from Typhoon Soulik.  Tropical Storm Cimaron is forecast to stay just southeast of the divergence from Soulik.  If it does that, Cimaron will strengthen into a typhoon during the next few days.  However, if Cimaron moves under the upper level divergence from Typhoon Soulik, then the vertical wind shear will keep Cimaron from strengthening.

Typhoon Soulik strengthened into the equivalent of a major hurricane west of Iwo To on Saturday.  At 11:00 p.m. EDT on Saturday the center of Typhoon Soulik was located at latitude 25.2°N and longitude 138.8°E which put it about 145 miles (235 km) west-northwest of Iwo To.  Soulik was moving toward the west-northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (215 km/h).  The minimum surface pressure was 952 mb.

Typhoon Soulik is well organized.  There is a circular eye at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms.  Several bands of showers and thunderstorms are revolving around the core of Soulik.  Storms near the core are generating strong upper level divergence which is pumping mass away in all directions.  Winds to typhoon force extend out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extend out about 170 miles (280 km) from the center.

Typhoon Soulik will move through an area favorable for strong typhoons.  Soulik will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Soulik could maintain its intensity for another 24 to 48 hours.

Typhoon Soulik will move around the western end of a ridge in the middle troposphere.  The ridge will steer Soulik in a general northwesterly direction.  On it anticipated track Typhoon Soulik will move toward the Ryukyu Islands.  Tropical Storm Cimaron will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  On its anticipated track, Cimaron will move near the northern Marianas in 24 to 36 hours.  Tropical Storm Cimaron could approach Iwo To in about three days.

Tropical Storm Leepi Forms Southeast of Iwo To

Tropical Storm Leepi formed southeast of Iwo To on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Leepi was located at latitude 21.5°N and longitude 142.7°W which put it about 285 miles (465 km) south-southeast of Iwo To.  Leepi was moving toward the north-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 995 mb.

A distinct center of circulation developed within an area of thunderstorms between the Northern Marianas and Iwo To and the Japan Meteorological Agency designated the system as Tropical Storm Leepi.  The distribution of thunderstorms around Tropical Storm Leepi was very asymmetrical.  The stronger thunderstorms were all occurring in bands in the eastern half of the circulation.  The bands in the western half of the circulation consisted of showers and low clouds.  Storms near the center of Leepi were generating upper level divergence which was pumping mass away to the northeast of the tropical storm.

Tropical Storm Leepi will move through an environment somewhat favorable for intensification during the next 12 to 24 hours.  Leepi will move over water where the Sea Surface Temperature is near 29°C.  An upper level trough northeast of the tropical storm was producing southwesterly winds which were causing moderate vertical wind shear.  The wind shear was inhibiting the divergence to the west of Tropical Storm Leepi.  The tropical storm also appeared to be drawing drier air into the western side of the circulation.  Leepi could intensify on Sunday, but it will move into an area of stronger upper level winds in a day or so.  Increased vertical wind shear will likely start to weaken Tropical Storm Leepi after that occurrs.

Tropical Storm Leepi will move near the western end of a ridge in the middle troposphere.  The ridge will Leepi in a general motion toward the northwest.  On its anticipated track Tropical Storm Leepi will move near Iwo To in about 24 hours.  Leepi could approach the northern Ryukyu Islands and Kyushu in about three days.

Elsewhere over the Western North Pacific, Tropical Storm Yagi passed over the southern Ryukyu Islands on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Yagi was located at latitude 25.6°N and longitude 124.8°E which put it about 250 miles (400 km) east of Taipei, Taiwan.  Yagi was moving toward the west at 14 m.p.h. (22 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 993 mb.

Typhoon Shanshan Brushes East Coast of Honshu

Typhoon Shanshan brushed the east coast of Honshu late on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Shanshan was located at latitude 36.8°N and longitude 141.5°E which put it about 40 miles (65 km) east of Iwaki, Japan.  Shanshan was moving toward the north at 12 m.p.h. (19 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 975 mb.

The center of Typhoon Shanshan moved very close to the east coast of Honshu near Choshi on Wednesday and then it moved nearly parallel to the coast.  The stronger winds and heavier rain were occurring on the eastern side of Shanshan, and they passed east of Honshu.  The winds were weaker and the rain was lighter in the western side of Typhoon Shanshan.  Winds to tropical storm force were occurring near the east coast of Honshu.  The typhoon had little effect on the weather near Tokyo.  Some locations near the coast did have a period of heavier rain after the center of Typhoon Shanshan passed and the winds blew from the southwest toward the coast.

Typhoon Shanshan will affect the coast of Honshu for another six to twelve hours, while the center moves nearly parallel to the coast.  Shanshan will reach an area where stronger westerly winds are blowing in the middle and upper troposphere.  Those winds will turn Typhoon Shanshan toward the east and they will push it away from Japan.  The stronger winds will also cause significant vertical wind shear.  Shanshan will move over cooler water when it turns eastward.  The combination of vertical wind shear and cooler water will cause Typhoon Shanshan to weaken and it could make a transition to an extratropical cyclone in a day or two.

Elsewhere over the Western North Pacific, Tropical Storm Yagi formed southeast of Okinawa on Wednesday.  At 11:00 p.m. EDT the center of Tropical Storm Yagi was located at latitude 21.3°N and longitude 133.6°E which put it about 530 miles (855 km) southeast of Okinawa.  Yagi was moving toward the northwest at 7 m.p.h. (11 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 993 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 Storm Ampil Moves Toward Okinawa

Tropical Storm Ampil moved toward Okinawa on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Ampil was located at latitude 23.3°N and longitude 130.6°E which put it about 320 miles (520 km) southeast of Okinawa.  Ampil was moving toward the north-northwest at 11 m.p.h. (17 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 Ampil strengthened on Thursday, although its appearance on satellite imagery was not particularly impressive.  There was a distinct low level center of circulation, but the most of the stronger thunderstorms were occurring in a rainband southwest of the center of circulation.  Bands in other parts of the tropical storm consisted primarily of showers and low clouds.  It appeared that some drier air could have wrapped around the southern and eastern sides of the circulation.  The drier air may have inhibited the development of taller thunderstorms in those parts of Tropical Storm Ampil.  The circulation was fairly large and winds to tropical storm force extended out about 185 miles (295 km) from the center of circulation.

Tropical Storm Ampil will move through an environment that could support further intensification during the next day or two.  Ampil will move over water where the Sea Surface Temperature is near 29°C.  It will be near the eastern end of an upper level low, but Tropical Storm Ampil will move under a zone where the upper level winds will not be too strong.  There will be some vertical wind shear, but the shear will not be strong enough to prevent intensification.  The main factor that could inhibit intensification will be the drier air already around the circulation.  If the strong rainband in the southwestern part of Tropical Storm Ampil wraps around the center of circulation, it could prevent the drier air from affecting the core of the tropical storm.  If that happens, the Tropical Storm Ampil would be likely to intensify and it could become a typhoon.  However, if the drier air works its way into the center of circulation, then Ampil will not intensify.

Tropical Storm Ampil will move southwest of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Ampil in a northwesterly direction during the next 24 to 48 hours.  On its anticipated track Tropical Storm Ampil could be near Okinawa and the Ryukyu Islands in less than 24 hours.  Ampil could reach the east coast of China south of Shanghai in about two days.  Tropical Storm Ampil will bring gusty winds to the Ryukyu Islands later on Friday.  Ampil could bring gusty winds and locally heavy rain to parts of eastern China during the weekend.

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.