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Typhoon Chanthu Moves Away from Taiwan

Typhoon Chanthu moved away from Taiwan on Sunday. At 11:00 a.m. EDT on Sunday the center of Typhoon Chanthu was located at latitude 26.8°N and longitude 122.7°E which put it about 105 miles (165 km) northeast of Taipei, Taiwan. Chanthu was moving toward the north-northeast at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h). The minimum surface pressure was 965 mb.

Typhoon Chanthu moved away from Taiwan on Sunday and the weather conditions were improving there. The core of Chanthu passed east of Taiwan and so it remained intact. A small circular eye was present at the center of Typhoon Chanthu. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Multiple bands of showers and thunderstorms were revolving around the core of Chanthu. Storms near the core generated upper level divergence that pumped mass away to the north of the typhoon.

The overall circulation of Typhoon Chanthu was larger after it moved past Taiwan. Winds to typhoon force extended out 25 miles (40 km) from the center of Chanthu. Winds to tropical storm force extended out 190 miles (305 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 19.2. The Hurricane Size Index (HSI) was 10.7 and the Hurricane Wind Intensity Size Index (HWISI) was 29.9. Typhoon Chanthu was capable of causing regional serious damage.

Typhoon Chanthu will move through an environment that will be mostly unfavorable for intensification during the next 36 hours. Chanthu will move over water where the Sea Surface Temperature is near 29˚C. An upper level trough over eastern China will produce southwesterly winds that will blow toward the top of Chanthu’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will likely be strong enough to cause Typhoon Chanthu to weaken gradually.

Typhoon Chanthu will move around the western side of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Chanthu toward the north during the next 24 hours. On its anticipated track Typhoon Chantu will continue to move away from Taiwan. Chanthu could approach the coast of Chine south of Shanghai in 24 hours. Typhoon Chanthu will bring gusty winds and locally heavy rain to the parts of east coast of China on Monday.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Conson weakened near the coast of Vietnam. At 11:00 a.m. EDT on Sunday the center of Tropical Depression Conson was located at latitude 15.4°N and longitude 109.1°E which put it about 70 miles (110 km) southeast of Da Nang, Vietnam. Conson was stationary. 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 1003 mb.

Typhoon Chanthu Brings Wind and Rain to Taiwan

Typhoon Chanthu brought wind and rain to Taiwan on Saturday morning. At 11:00 a.m. EDT on Saturday the center of Typhoon Chanthu was located at latitude 22.2°N and longitude 121.8°E which put it about 100 miles (160 km) south-southeast of Hualien, Taiwan. Chanthu was moving toward the north-northeast at 8 m.p.h. (13 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 938 mb.

Bands in the northwestern part of Typhoon Chanthu brought wind and rain to eastern Taiwan on Saturday morning. Typhoon Chanthu appeared to be in the middle of another eyewall replacement cycle. A small eye was present at the center of Chanthu. The eye was surrounded by concentric eyewalls. The strongest winds were occurring in the innermost eyewall. Bands of showers and thunderstorms were revolving around the core of Typhoon Chanthu. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The current eyewall replacement cycle increased the overall size of the circulation around Typhoon Chanthu. Winds to typhoon force extended out 35 miles (55 km) from the center of Chanthu. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 28.3. The Hurricane Size Index (HSI) was 12.5 and the Hurricane Wind Intensity Size Index (HWISI) was 40.8. Typhoon Chanthu was capable of causing regional severe damage.

Typhoon Chanthu will move over water capable of supporting an intense typhoon during the next 24 hours. Chanthu 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. The current eyewall replacement cycle could cause Typhoon Chanthu to weaken if the innermost eyewall dissipates.

Typhoon Chanthu will move around the western end of a high pressure system over the Western North Pacific. The high pressure system will steer Chanthu toward the north during the next 36 hours. On its anticipated track the center of Typhoon Chanthu will be near northeastern Taiwan in 18 hours. Typhoon Chanthu will drop very heavy rain over eastern Taiwan. The risk of flash floods is very high. Even though the core of Chanthu may pass just east of Taiwan, strong winds are likely to cause damage along the east coast of Taiwan.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Conson was approaching toward central Vietnam. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Conson was located at latitude 15.4°N and longitude 109.0°E which put it about 65 miles (105 km) southeast of Da Nang, Vietnam. Conson was moving toward the west-southwest at 5 m.p.h. (8 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.

Typhoon Chanthu Brings Wind and Rain to Northeast Luzon

Typhoon Chanthu brought wind and rain to northeastern Luzon on Friday. At 5:00 a.m. EDT on Friday the center of Typhoon Chanthu was located at latitude 18.3°N and longitude 123.1°E which put it about 100 miles (160 km) east of Aparri, Philippines. Chanthu was moving toward the northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 165 m.p.h. (265 km/h) and there were wind gusts to 200 m.p.h. (320 km/h). The minimum surface pressure was 915 mb.

Even though the center of Typhoon Chanthu was passing northeast of northeastern Luzon, bands on the western side of Chanthu brought gusty wind and heavy rain to northeastern Luzon. Typhoon Chanthu strengthened back to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale after it completed an eyewall replacement cycle on Thursday. A circular eye was present at the center of Chanthu. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Storms near the core of Chanthu generated strong upper level divergence that pumped mass away from the typhoon in all directions.

The circulation around Typhoon Chanthu was relatively small. Winds to typhoon force extended out 45 miles (75 km) from the center of Chanthu. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 36.8. The Hurricane Size Index (HSI) was 14.1 and the Hurricane Wind Intensity Size Index (HWISI) was 50.9. Typhoon Chanthu was capable of causing regional catastrophic damage.

Typhoon Chanthu will move over water capable of supporting an intense typhoon during the next 24 hours. Chanthu 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. If the inner end of a rainband wraps around the existing eye and eyewall, another eyewall replacement cycle could start. If another eyewall replacement cycle occurs, Typhoon Chanthu would weaken, but the size of the circulation would increase.

Typhoon Chanthu will move around the western end of a high pressure system during the next few days. The high pressure system will steer Chanthu toward the northwest during the next 24 hours. On its anticipated track Typhoon Chanthu will gradually move away from northeastern Luzon. Chantu will approach southern Taiwan in 24 hours. Typhoon Chanthu will bring very strong winds and heavy rain to Taiwan. Widespread flash floods could occur.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Conson moved toward central Vietnam. At 5:00 a.m. EDT on Friday the center of Tropical Storm Conson was located at latitude 15.6°N and longitude 111.7°E which put it about 250 miles (400 km) east of Da Nang, Vietnam. Conson was moving toward the west at 9 m.p.h. (15 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.

Dangerous Typhoon Chanthu Nears Northeast Luzon

Dangerous Typhoon Chanthu neared northeastern Luzon on Thursday night. At 11:00 p.m. EDT on Thursday the center of Typhoon Chanthu was located at latitude 17.5°N and longitude 123.7°E which put it about 135 miles (215 km) southeast of Aparri, Philippines. Chanthu was moving toward the west-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h). The minimum surface pressure was 925 mb.

Typhoon Chanthu completed an eyewall replacement cycle on Thursday and Chanthu was strengthening again. The original eye and eyewall were almost entirely dissipated. A new, slightly larger eye was visible at the center of Typhoon Chanthu 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 Chanthu. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon.

Although the eyewall replacement cycle increased the size of the core of Typhoon Chanthu, the total circulation around Chanthu was relative small. Winds to typhoon force extended out 45 miles (75 km) from the center of Chanthu. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 31.6. The Hurricane Size Index (HSI) was 13.7 and the Hurricane Wind Intensity Size Index (HWISI) was 45.3. Typhoon Chanthu was capable of causing regional severe damage.

Typhoon Chanthu will move through an environment favorable for intensification during the next 12 hours. Chanthu 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 Chanthu could strengthen during the next 12 hours. Chanthu will weaken if the core of the typhoon moves over northeastern Luzon. If the core of Typhoon Chanthu passes northeast of Luzon, then it could maintain its intensity during the next 36 hours.

Typhoon Chanthu will move around the western end of a high pressure system during the next few days. The high pressure system will steer Chanthu toward the northwest during the next 24 hours. On its anticipated track the core of Typhoon Chanthu will pass very close to northeastern Luzon. Chanthu could cause severe damage to northeastern Luzon. Typhoon Chantu will bring very strong winds and locally heavy rain. Heavy rain is likely to cause flash floods. Typhoon Chantu could affect Taiwan during the weekend.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Conson moved toward central Vietnam. At 11:00 p.m. EDT on Thursday the center of Tropical Storm Conson was located at latitude 15.8°N and longitude 112.2°E which put it about 280 miles (460 km) east of Da Nang, Vietnam. Conson was moving toward the west-southwest at 13 m.p.h. (20 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.

Typhoon Chanthu Strengthens to Equivalent of Cat. 5 Hurricane

Typhoon Chanthu intensified to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale east of northern Luzon on Wednesday. At 5:00 a.m. EDT on Wednesday the center of Typhoon Chanthu was located at latitude 15.5°N and longitude 130.8°E which put it about 630 miles (1015 km) east-southeast of Aparri, Philippines. Chanthu was moving toward the west-southwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 195 m.p.h. (315 km/h). The minimum surface pressure was 915 mb.

Typhoon Chanthu intensified to the equivalent of a Category 5 hurricane on Wednesday morning. A small eye was at the center of Typhoon Chanthu. 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 revolved around the core of Chanthu. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon. The inner end of a rainband wrapped part of the way around the core of Typhoon Chanthu. Concentric eyewalls might be developing, which would indicate the start of an eyewall replacement cycle.

The circulation around Typhoon Chanthu was small. Winds to typhoon force extended out 20 miles (30 km) from the center of Chanthu. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 35.0. The Hurricane Size Index (HSI) was 7.1 and the Hurricane Wind Intensity Size Index (HWISI) was 42.1. Typhoon Chanthu was capable of causing localized catastrophic damage.

Typhoon Chanthu will move through an environment capable of maintaining a strong typhoon during the next 48 hours. Chanthu 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. If an eyewall replacement cycle occurs, Typhoon Chanthu will weaken when the inner eyewall weakens. An eyewall replacement cycle would increase the size of the circulation around Chanthu when the outer eyewall forms.

Typhoon Chanthu will move south of a high pressure system over the Western North Pacific Ocean. The high will steer Chanthu toward the west during the next several days. On its anticipated track Typhoon Chanthu could approach northeastern Luzon in 48 hours. Chanthu will likely still be a powerful typhoon when it approaches Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Conson continued to bring wind and rain to parts of Luzon. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Conson was located at latitude 14.3°N and longitude 120.5°E which put it about 35 miles (55 km) south-southwest of Manila, Philippines. Conson was moving toward the northwest 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 988 mb.

Typhoon Chanthu Rapidly Intensifies to Equivalent of Major Hurricane

Typhoon Chanthu rapidly intensified to the equivalent of a major hurricane over the Western North Pacific Ocean on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Typhoon Chanthu was located at latitude 16.3°N and longitude 133.0°E which put it about 915 miles (1475 km) east-southeast of Taiwan. Chanthu was moving toward the west at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 145 m.p.h. (230 km/h) and there were wind gusts to 175 m.p.h. (280 km/h). The minimum surface pressure was 929 mb.

Former Tropical Storm Chanthu rapidly intensified from a minimal tropical storm to the equivalent of a major hurricane during the past 24 hours. A small eye quickly developed at the center of Typhoon Chanthu. 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 Chanthu. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Chanthu was small. Winds to typhoon force extended out 20 miles (30 km) from the center of Chanthu. Winds to tropical storm force extended out 85 miles (135 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 30.0. The Hurricane Size Index (HSI) was 7.4 and the Hurricane Wind Intensity Size Index (HWISI) was 37.4. Typhoon Chanthu was capable of causing localized severe damage.

Typhoon Chanthu will move through an environment favorable for intensification during the next 24 hours. Chanthu 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 Chanthu could continue to intensify during the next 24 hours and there is a chance it could strengthen to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.

Typhoon Chanthu will move south of a high pressure system over the Western North Pacific Ocean. The high will steer Chanthu toward the west during the next several days. On its anticipated track Typhoon Chanthu could approach northeastern Luzon in 60 hours. Chanthu could be near Taiwan in less than four days.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Conson brought wind and rain to Luzon. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Conson was located at latitude 13.5°N and longitude 121.7°E which put it about 110 miles (175 km) southeast of Manila, Philippines. Conson was moving toward the west-northwest at 9 m.p.h. (15 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 988 mb.

Tropical Storm Conson Brings Wind and Rain to Central Philippines

Tropical Storm Conson brought wind and rain to the central Philippines on Monday. At 5:00 p.m. EDT on Monday the center of Tropical Storm Conson was located at latitude 11.7°N and longitude 124.6°E which put it about 50 miles (80 km) south-southeast of Calbayog, Philippines. Conson was moving toward the west-northwest at 12 m.p.h. (19 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 985 mb.

The center of Tropical Storm Conson made landfall on the east coast of Samar near Borongan on Monday. Conson was nearly a typhoon at the time of landfall. A small eye was visible at the center of Tropical Storm Conson on both radar and microwave satellite images. Conson produced gusty winds as it passed over Samar. Winds to tropical storm force extended out 45 miles (75 km) from the center of circulation. Tropical Storm Conson dropped heavy rain on Samar, Leyte, northern Cebu and northeastern Panay. Heavy rain could result in flash floods in some locations.

Tropical Storm Conson will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high will steer Conson toward the northwest during the next 36 hours. On its anticipated track Tropical Storm Conson will pass over the Visayan Sea and the Sibuyan Sea. The center of Conson could pass over Masbate during the next 12 hours. Tropical Storm Conson could reach southern Luzon in a day or so. Conson could be be near Manila in 48 hours. Tropical Storm Conson will bring gusty winds and locally heavy rain to parts of Masbate, Mindoro and southern Luzon.

Tropical Storm Conson will move through an environment mostly favorable for intensification during the next 24 hours. Conson 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. Since the circulation around Tropical Storm Conson is small, it is likely to weaken each time the center passes over land. The intensity of Conson could fluctuate when it moves over islands and water surfaces.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 19W was organizing quickly and it appeared to be on the verge of strengthening to a tropical storm. At 5:00 p.m. EDT on Monday the center of Tropical Depression 19W was located at latitude 15.5°N and longitude 137.1°E which put it about 1170 miles (1890 km) east-southeast of Taiwan. The tropical depression was moving toward the northwest at 8 m.p.h. (13 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 1003 mb. Tropical Depression 19W is forecast to move toward the west-northwest and to intensify.

Tropical Storm Conson Develops Quickly near the Philippines

Tropical Storm Conson developed quickly near the Philippines on Monday morning. At 5:00 a.m. EDT on Monday the center of Tropical Storm Conson was located at latitude 11.0°N and longitude 126.6°E which put it about 120 miles (195 km) east-southeast of Dolores, Philippines. Conson was moving toward the west-northwest at 8 m.p.h. (13 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 991 mb.

The circulation around Tropical Storm Conson organized quickly on Monday morning, The inner end of a primary rainband wrapped around the center of circulation. A small circular eye was at the center of Conson on microwave satellite images. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. The circulation around Tropical Storm Conson was small. Winds to tropical storm force extended out 35 miles (55 km) from the center of Conson.

Tropical Storm Conson will move through an environment favorable for intensification during the next 12 hours. Conson 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. Tropical Storm Conson is likely to intensify during the next 12 hours and it could strengthen to a typhoon.

Tropical Storm Conson will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high will steer Conson toward the northwest during the next 24 hours. On its anticipated track Tropical Storm Conson will reach northeastern Samar in 12 hours. Conson could be a typhoon when it reaches Samar. It will bring strong winds and locally heavy rain to Samar. Heavy rain could cause flash floods in some locations. Conson will weaken when the center passes over northeastern Samar. Since the circulation of Tropical Storm Conson is small, it could weaken quickly over land. The center of Tropical Storm Conson could move back over water when it moves north of Samar. The circulation could strengthen again when that happens. Conson could reach southeastern Luzon in a day or so.

Elsewhere over the Western North Pacific, Tropical Depression 19W formed north of Yap. At 5:00 a.m. EDT on Monday the center of Tropical Depression 19W was located at latitude 14.3°N and longitude 138.1°E which put it about 310 miles (500 km) north of Yap. The tropical depression was moving toward the north 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 1006 mb. Tropical Depression 19W is forecast to move toward the west-northwest and to strengthen.

Tropical Storm Nangka Makes Landfall in Vietnam

Tropical Storm Nangka made landfall on the coast of northern Vietnam on Wednesday morning.  Nangka weakened to a tropical depression after the center moved over land.  At 8:00 a.m. EDT on Wednesday the center of Tropical Depression Nangka was located at latitude 20.0°N and longitude 105.0°E which put it about 80 miles (130 km) southwest of Hanoi, Vietnam.  Nangka was moving toward the west at 12 m.p.h. (19 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 1002 mb.

The center of Tropical Storm Nangka made landfall on the coast of Vietnam about 70 miles (110 km) southeast of Hanoi on Wednesday morning.  Nangka brought gusty winds and heavy rain to the northern coast of Vietnam.  Nangka quickly weakened to a tropical depression when it moved westward over northern VIetnam.  Bands of showers and thunderstorms dropped locally heavy rain over parts of northern Vietnam.

Tropical Depression Nangka will continue to move toward the west until the circulation spins down over northern Laos on Thursday.  Nangka will continue to drop locally heavy rain over parts of northern Vietnam and northern Laos during the next 24 hours.  Heavy rain could cause flash floods in some locations.

Tropical Storm Nangka Brings Wind and Rain to Hainan

Tropical Storm Nangka brought wind and rain to Hainan Island on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Nangka was located at latitude 19.1°N and longitude 110.0°E which put it about 70 miles south-southwest of Haikou, China.  Nangka was moving toward the west-northwest at 9 m.p.h. (15 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.

The center of Tropical Storm Nangka moved directly across Hainan Island on Tuesday.  Nangka strengthened before it made landfall on the east coast of Hainan.  Winds to tropical storm force extended out 200 miles (320 km) from the center of Tropical Storm Nangka.  So, Nangka may have produced tropical storm force winds over much of Hainan.  Thunderstorms near the center of circulation and in bands revolving around the center were dropping heavy rain over parts of Hainan.  The heavy rain was likely to cause flash floods in some locations.

Tropical Storm Nangka will weaken while it moves across Hainan.  Nangka will move into an environment favorable for intensification for about 12 hours when it moves west of Hainan Island.  Nangka 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 over eastern Asia.  The ridge will produce 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 Tropical Storm Nangka from strengthening again.

Tropical Storm Nangka will move south of a high pressure system over eastern Asia.  The high will steer Nangka toward the west during the next 48 hours.  Tropical Storm Nangka will move west of Hainan Island in about 6 hours.  On its anticipated track Nangka will make landfall on the northern coast of Vietnam southeast of Hanoi in about 18 hours.  Tropical Storm Nangka will bring gusty winds and locally heavy rain to northern Vietnam.  Heavy rain will cause flash floods in some locations.