Tag Archives: Vietnam

Typhoon In-Fa Churns Southeast of Ishigaki

Typhoon In-Fa churned southeast of Ishigaki, Japan on Thursday. At 11:00 a.m. EDT on Thursday the center of Typhoon In-Fa was located at latitude 23.7°N and longitude 125.8°E which put it about 120 miles (195 km) southeast of Ishigaki, Japan. In-Fa was moving toward the northwest at 2 m.p.h. (3 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 957 mb.

Typhoon In-Fa went through an eyewall replacement cycle as it moved slowly toward the southwestern Ryukyu Islands on Thursday. The inner end of an rainband wrapped completely around the original eye and eyewall. Two concentric eyewalls existed simultaneously for a time on Wednesday. Low level convergence became concentrated in the newer, outer eyewall and the inner eyewall dissipated. The eyewall replacement cycle left a much larger eye with a diameter of 65 miles (105 km) at the center of Typhoon In-Fa. Bands of showers and thunderstorms were revolving around the new, larger eye. Storms near the eye generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon In-Fa was large. Winds to typhoon force extended out 70 miles (110 km) from the center of In-Fa. Winds to tropical storm force extended out 230 miles (370 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon In-Fa was 16.5. The Hurricane Size Index (HSI) was 27.4 and the Hurricane Wind Intensity Size Index (HWISI) was 43.9 .

Typhoon In-Fa will move through an environment favorable for intensification during the next 24 hours. In-Fa will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon In-Fa has moved little during the past 12 hours and it has mixed cooler water to the surface. Once In-Fa starts to move a little faster, the core of the typhoon will move back over warmer water. Typhoon In-Fa is likely to strengthen during the next 24 hours and it could intensify to the equivalent of a major hurricane.

Typhoon In-Fa will move around the southwestern part of a high pressure system over the Western North Pacific Ocean during the next 36 hours. The high will steer In-Fa toward the northwest. On its anticipated track the center of Typhoon In-Fa will be near the southwestern Ryukyu Islands in 18 hours. In-Fa will be capable of causing widespread serious damage. It will also cause a significant storm surge. Typhoon In-Fa will drop heavy rain and flash floods are likely. The core of In-Fa could be northeast of Taiwan in 36 hours. In-Fa will also drop heavy rain on parts of northern Taiwan and flash floods are likely there as well.

Elsewhere, Tropical Depression Cempaka continued to meander over southern China. At 11:00 a.m. EDT on Thursday the center of Tropical Depression Cempaka was located at latitude 21.9°N and longitude 107.8°E which put it about 25 miles (40 km) north of Mong Cai, Vietnam. Cempaka was moving toward the northwest 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 1003 mb.

Tropical Storm Koguma Nears Vietnam

The center of Tropical Storm Koguma moved closer to northern Vietnam on Saturday. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Koguma was located at latitude 20.2°N and longitude 106.9°E which put it about 115 miles (185 km) southeast of Hanoi, Vietnam. Koguma was moving toward the northwest at 20 m.p.h. (32 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 997 mb.

The circulation around former Tropical Depression 05W strengthened slightly on Saturday and the system was upgraded to Tropical Storm Koguma. Even though the circulation around the former tropical depression was a little stronger, the distribution of thunderstorms around Tropical Storm Koguma was still asymmetrical. The strongest thunderstorms were occurring in bands southwest of the center of Koguma. Bands in the other parts of the tropical storm consisted primarily of showers and lower clouds. An upper level ridge centered over southern China was producing moderate northeasterly winds that were blowing toward the top of the depression. Those winds were causing moderate vertical wind shear and they were also causing the asymmetrical distribution of thunderstorms.

Tropical Storm Koguma will move into an environment only marginally favorable for intensification during the next few hours. Koguma will move over an area where the Sea Surface Temperatures are near 30°C. However, the upper level ridge over southern China will continue to produce moderate vertical wind shear. The moderate wind shear will keep Tropical Storm Koguma from strengthening significantly before it reaches Vietnam. The circulation around Koguma will weaken after the center moves over Vietnam.

Tropical Storm Koguma will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean during the next 24 hours. The high pressure system will steer Koguma toward the northwest. On its anticipated track the center of Tropical Storm Koguma will make landfall on the coast of northern Vietnam south of Haiphong in a few hours. Koguma will bring gusty winds to parts of northern Vietnam. Since the heaviest rain is falling southwest of the center of Tropical Storm Koguma, heavy rain is already falling over parts of northern Vietnam, northern Laos and extreme northeastern Thailand. The heavy rain could cause flash floods in some locations.

Tropical Depression Forms South of Hainan Island

A tropical depression formed just to the south of Hainan Island on Friday night. At 11:00 p.m. EDT on Friday the center of Tropical Depression 05W was located at latitude 18.3°N and longitude 109.5°E which put it about 35 miles (55 km) south of Sanya, China. The depression was moving toward the west at 16 m.p.h. (26 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 1000 mb.

Thunderstorms developed closer to the center of a low pressure system south of Hainan Island on Friday night and both the Japan Meteorological Agency and the Joint Typhoon Warning Center designated the system as a tropical depression. The distribution of thunderstorms around Tropical Depression 05W was asymmetrical. The strongest thunderstorms were occurring in bands southwest of the center of the tropical depression. Bands in the other parts of the circulation consisted primarily of showers and lower clouds. An upper level ridge centered over southern China was producing moderate northeasterly winds that were blowing toward the top of the depression. Those winds were causing moderate vertical wind shear and they were also causing the asymmetrical distribution of thunderstorms.

The center of Tropical Depression 05W will move near Hainan Island during the next few hours. The northern half of the circulation around the tropical depression will be over Hainan Island, which will inhibit intensification. Tropical Depression 05W will move into an environment favorable for intensification when it moves west of Hainan Island. The tropical depression will move over an area where the Sea Surface Temperatures are near 30°C. The upper level ridge over southern China will continue to produce moderate vertical wind shear. Even with the moderate wind shear, Tropical Depression 05W is likely to intensify to a tropical storm during the next 24 hours.

Tropical Depression 05W will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean during the next 36 hours. The high pressure system will steer the tropical depression toward the west-northwest. On its anticipated track the center of Tropical Depression 05W will pass near the southern part of Hainan Island. Since the strongest thunderstorms are in the southwestern part of the circulation, the tropical depression will cause mainly gustier winds over Hainan Island. Tropical Depression 05W could approach northern Vietnam in 24 hours. It could bring gusty winds and locally heavy rain to parts of northern Vietnam. Heavy rain could cause flash floods in some locations.

Tropical Storm Krovanh Develops over South China Sea

Tropical Storm Krovanh developed over the South China Sea on Sunday. At 4:00 p.m. EST on Sunday the center of Tropical Storm Krovanh was located at latitude 9.7°N and longitude 113.9°E which put it about 515 miles (830 km) east of Ho Chi Minh City, Vietnam. Krovanh was moving toward the west-southwest 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 1001 mb.

The circulation around Tropical Storm Krovanh was very asymmetrical. A high pressure system over eastern Asia was contributing to a strong pressure gradient northwest of Krovanh. The pressure gradient between the high pressure system and Krovanh was producing strong northeasterly winds in the northwestern quadrant of the tropical storm. Winds to tropical storm force extended out 300 miles (485 km) in the northwestern quadrant of Tropical Storm Krovanh. However, winds in the southeastern quadrant of Krovanh were blowing at less than tropical storm force.

Tropical Storm Krovanh will move through an environment that is only marginally favorable for intensification. Krovanh will move over water where the Sea Surface Temperature is near 27°C. So, there will be enough energy in the upper ocean to support intensification. However, the northeasterly winds on the northwestern side of Tropical Storm Krovanh will transport drier air into the circulation. The drier air will inhibit the development of thunderstorms. Krovanh will move under the southern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce strong easterly winds which will blow toward the top of the tropical storm. Those winds will cause moderate vertical wind shear, which will also inhibit intensification. Tropical Storm Krovanh could intensify a little during the next 24 hours, but the dry air and wind shear are likely to cause it to weaken next week.

Tropical Storm Krovanh will move around the southern side of the high pressure system over eastern Asia. The high will steer Krovanh toward the west-southwest during the next several days. On its anticipated track Tropical Storm Krovanh could be near the southernmost part of Vietnam in about three days.

Typhoon Vamco Strengthens to Equivalent of Major Hurricane

Typhoon Vamco strengthened to the equivalent of a major hurricane east of Vietnam on Friday. At 4:00 p.m. EST on Friday the center of Typhoon Vamco was located at latitude 15.7°N and longitude 111.9°E which put it about 275 miles (440 km) east of Da Nang, Vietnam. Vamco was moving toward the west at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 954 mb.

Typhoon Vamco rapidly intensified into the equivalent of a major hurricane over the East China east of Vietnam on Friday. The circulation contracted around a small clear eye. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Vamco. Storms near the core were generating strong upper level divergence which was pumping mass away fro the typhoon. The removal of mass allowed the pressure to decrease rapidly which contributed to the rabid intensification.

Winds to typhoon force extended out 40 miles (65 km) from the center of Typhoon Vamco. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Vamco was 25.1. The Hurricane Size Index (HSI) was 16.7 and the Hurricane Wind Intensity Size Index (HWISI) was 41.8. Vamco was capable of causing significant damage.

Typhoon Vamco will move through an environment that will become less favorable for intensification during the next day or so. Vamco will move over water where the Sea Surface Temperature is near 28°C. So, there will be enough energy in the upper ocean to support an intense typhoon. However, northeasterly winds will transport drier air over eastern Asia toward the western side of Typhoon Vamco. Vamco is likely to start to weaken when the drier air is pulled into the core of the circulation.

Typhoon Vamco will move south of a high pressure system over the eastern Asia. The high will steer Vamco toward the west during the next several days. On its anticipated track Typhoon Vamco will approach the coast of Vietnam north of Da Nang in about 24 hours. Vamco is likely to still be a typhoon when it reaches Vietnam. Typhoon Vamco will drop heavy rain over Vietnam, Laos and northeastern Thailand. The rain will fall on saturated surfaces and floods will occur in those areas.

Typhoon Vamco Moves Toward Vietnam

Typhoon Vamco moved toward Vietnam on Thursday. At 10:00 p.m. EST on Thursday the center of Typhoon Vamco was located at latitude 15.5°N and longitude 115.0°E which put it about 480 miles (775 km) east of Da Nang, Vietnam. Vamco was moving toward the west-northwest at 9 m.p.h. (15 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. (165 km/h). The minimum surface pressure was 972 mb.

One day after causing widespread damage on Luzon, Typhoon Vamco moved across the South China Sea toward Vietnam. An eye was present at the center of Vamco, but there were clouds in the eye. The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Vamco. The size of the circulation around Vamco increased after it crossed Luzon. Winds to typhoon force extended out 75 miles (120 km) from the center of circulation. Winds to tropical storm force extended out 230 miles (370 km) from the center.

Typhoon Vamco will move through an environment that could allow it to maintain its intensity for another 24 to 36 hours. Vamco will move over water where the Sea Surface Temperature is near 28°C. It will move under the southern portion of an upper level ridge over eastern Asia. The ridge will produce easterly winds which will blow toward the top of the Typhoon Vamco. Those winds will cause some vertical wind shear, but the shear will not be too strong. Northeasterly winds will transport drier air toward the western side of Typhoon Vamco when it moves closer to land in 24 to 36 hours. Vamco could start to weaken if the drier air is pulled into the core of the typhoon.

Typhoon Vamco will move south of a high pressure system over the eastern Asia. The high will steer Vamco toward the west-northwest during the next several days. On its anticipated track Typhoon Vamco will approach the center coast of Vietnam in about 36 hours.

Tropical Storm Etau Nears Vietnam, Vamco Threatens Philippines

Tropical Storm Etau neared Vietnam on Monday and newly formed Tropical Storm Vamco threatened the Philippines. At 4:00 a.m. EST on Monday the center of Tropical Storm Etau was located at latitude 12.8°N and longitude 111.6°E which put it about 170 miles (280 km) east of Tuy Hoa, Vietnam. Etau was moving toward the west at 15 m.p.h. (24 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 995 mb.

The distribution of thunderstorms around Tropical Storm Etau was asymmetrical. Etau was moving under the southern part of an upper level ridge over eastern Asia. The ridge was producing easterly winds which were blowing toward the top of Etau. Those winds were causing moderate vertical wind shear. The shear was causing the stronger thunderstorms to occur in bands on the western side of Tropical Storm Etau. The bands in the eastern side of Etau consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 150 miles (240 km) in the northern half of Tropical Storm Etau. Winds to tropical storm force only extended out 50 miles in the southern half of Etau.

Tropical Storm Etau will move south of a high pressure system over eastern Asia. The high will steer Etau toward the west during the next two days. On its anticipated track the center of Etau will make landfall in Vietnam near Tuy Hoa in about 12 hours.

Tropical Storm Etau will move through an environment that should allow it to maintain its intensity until it makes landfall in Vietnam. Etau will move over water where the Sea Surface Temperature is near 28°C. The upper level ridge over eastern Asia will continue to cause moderate vertical wind shear which will limit intensification.

Since the stronger thunderstorms are in the western half of Tropical Storm Etau, heavy rain will fall over central Vietnam before the center of Etau makes landfall. Etau will drop locally heavy rain over central Vietnam, northern Cambodia, southern Laos and northeastern Thailand. The ground is already saturated in that region and flash floods are likely.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Vamco developed east of the Philippines. At 4:00 a.m. EST on Monday the center of Tropical Storm Vamco was located at latitude 12.8°N and longitude 130.6°E which put it about 370 miles (605 km) east of Laoang, Philippines. Vamco was moving toward the northwest at 13 m.p.h. (20 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. Tropical Storm Vamco is forecast to move toward Luzon and to strengthen into a typhoon.

Tropical Storm Atsani Passes Just South of Taiwan

Tropical Storm Atsani passed just south of Taiwan early on Friday. At 4:00 a.m. EST on Friday the center of Tropical Storm Atsani was located at latitude 21.5°N and longitude 120.7°E which put it about 30 miles (50 km) south of Taiwan. Atsani was moving toward the west-northwest at 12 m.p.h. (19 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 995 mb.

The center of Tropical Storm Atsani passed just to the south of the southern tip of Taiwan early on Friday. Radar images from the Taiwan Central Weather Bureau showed the well organized structure of Tropical Storm Atsani.

There was a small, tight center of circulation. The center was surrounded by a partial eyewall and the strongest winds were occurring in eyewall. Multiple bands of showers and thunderstorms were revolving around the core of Tropical Storm Atsani. Bands in the northern half of Atsani were dropping heavy rain over the southern half of Taiwan. The heaviest rain was falling in parts of southeastern Taiwan where the wind was pushing air up the eastern slopes of mountains. Flash floods are possible in those areas. Winds to tropical storm force extended out 100 miles (160 km) from the center of Atsani.

Tropical Storm Atsani will be in an environment favorable for intensification during the next 12 to 24 hours. Atsani will move over water where the Sea Surface Temperature is near 28°C. It will be in an area where the upper level winds are weaker and there will be little vertical wind shear. Tropical Storm Atsani could intensify during the next 24 hours and there is a chance it could strengthen into a typhoon. An upper level trough over eastern Asia will approach Atsani during the weekend. The trough will produce stronger southwesterly winds which will cause more vertical wind shear. Tropical Storm Atsani will weaken when the wind shear increases. If the shear is strong enough, the upper level winds could blow the top half of Atsani northeast of the low level circulation.

Tropical Storm Atsani will move south of a ridge of high pressure over the Western North Pacific Ocean. The high will steer Atsani toward the west during the next day or so. If the wind shear blows the top half of Tropical Storm Atsani northeast of the lower level circulation, then a surface high pressure system over eastern Asia could push the lower half of Atsani toward the southeast. On its anticipated track Tropical Storm Atsani will pass southeast of Hong Kong and it could eventually move toward Vietnam.

Elsewhere over the Western North Pacific Ocean, the remnants of former Typhoon Goni were dropping heavy rain over parts of Vietnam. At 4:00 a.m. EST on Friday the center of Tropical Depression Goni was located at latitude 13.8°N and longitude 108.3°E which put it about 50 miles (80 km) west of Quy Nhon, Vietnam. Goni was moving toward the west 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 1003 mb. Tropical Depression Goni is dropping heavy rain over ground that is already saturated and the rain will make ongoing floods worse.

Typhoon Molave Makes Landfall in Vietnam

Typhoon Molave made landfall on the central coast of Vietnam on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Typhoon Molave was located at latitude 15.1°N and longitude 109.1°E which put it about 10 miles (15 km) east of Quang Ngai, Vietnam. Molave was moving toward the west-northwest at 18 m.p.h. (30 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 957 mb.

Typhoon Molave made landfall on the coast of Vietnam near Quang Ngai on Tuesday night. Winds to typhoon force extended out 45 miles (75 km) from the center of Molave. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Molave was 17.8. The Hurricane Size Index (HSI) was 17.2 and the Hurricane Wind Intensity Size Index (HWISI) was 35.0. Molave was capable of causing regional serious damage.

Typhoon Molave will cause winds to typhoon force along the central coast of Vietnam. Molave will cause a significant storm surge near and to the north of where the center made landfall. Typhoon Molave will weaken steadily while it moves inland. Molave will drop locally heavy rain over parts of central Vietnam, southern Laos, northern Cambodia and northeastern Thailand. The surface in those areas is already saturated by rain dropped be previous tropical cyclones and other weather systems. Molave will almost certainly cause floods in some locations.

Elsewhere over the Western North Pacific, a new tropical depression formed east of the Philippines. At 11:00 p.m. EDT on Tuesday the center of Tropical Depression 22W was located at latitude 16.6°N and longitude 139.6°E which put it about 1200 miles (1965 km) east of the Philippines. The depression was moving toward the west at 7 m.p.h. (11 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 1006 mb. The tropical depression is forecast to move toward the Philippines and to strengthen into a typhoon.

Typhoon Molave Intensifies to Equivalent of a Major Hurricane

Typhoon Molave intensified to the equivalent of a major hurricane east of Vietnam on Monday night. At 11:00 p.m. EDT on Monday the center of Typhoon Molave was located at latitude 13.4°N and longitude 114.1°E which put it about 465 miles (750 km) east-southeast of Da Nang, Vietnam. Molave was moving toward the west at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h). The minimum surface pressure was 952 mb.

Typhoon Molave intensified steadily on Monday and it strengthened into the equivalent of a major hurricane over the South China Sea east of Vietnam. An eye appeared at the center of Typhoon Molave intermittently on satellite images. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Molave. Storms near the core generated upper level divergence which pumped mass away from the typhoon.

The circulation around Typhoon Molave increased in size on Monday. Winds to typhoon force extended out 60 miles (95 km) from the center of Molave. Winds to tropical storm force extended out 190 miles (305 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Molave was 20.6. The Hurricane Size Index (HSI) was 20.3 and the Hurricane Wind Intensity Size Index (HWISI) was 40.9. Typhoon Molave was capable of causing major damage.

Typhoon Molave will move through an environment favorable for intensification during the next 12 hours. Molave will move over water where the Sea Surface Temperature is near 29°C. It will move under the southern part of an upper level ridge. The ridge will produce easterly winds which will cause some vertical wind shear. The wind shear will limit the intensification during the next 12 hours. The upper level easterly winds could get stronger later on Tuesday. Stronger winds would cause more vertical wind shear which could cause Molave to start to weaken.

Typhoon Molave will move south of a high pressure system over eastern Asia. The high will steer Molave toward the west. On its anticipated track Typhoon Molave will approach the coast of Vietnam near Quy Nhon in about 24 hours. Molave will be capable of causing serious wind damage when it makes landfall. Wind blowing water toward the coast could cause a storm surge of up to 10 feet (3 meters) along the coast of central Vietnam. Typhoon Molave will drop locally heavy rain over central Vietnam, southern Laos, northern Cambodia and northeastern Thailand. Heavy rain could cause flash floods in some of those places.