Tag Archives: WP23

Namtheun Strengthens to a Typhoon North of Wake Island

Former Tropical Storm Namtheun strengthened to a typhoon over the Western North Pacific Ocean north of Wake Island on Saturday morning. At 5:00 a.m. EDT on Saturday the center of Typhoon Namtheun was located at latitude 31.4°N and longitude 165.6°E which put it about 800 miles (1290 km) north of Wake Island. Namtheun was moving toward the north-northeast at 18 m.p.h. (29 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. (150 km/h). The minimum surface pressure was 979 mb.

Former Tropical Storm Namtheun passed over water where the Sea Surface Temperatures are near 27˚C during the past 24 hours and it was able to extract enough energy to strengthen to a typhoon. A small eye formed at the center of Typhoon Namtheun. The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms. Storms near the center of Namtheun generated upper level divergence that pumped mass away from the typhoon. The circulation around Typhoon Namtheun was relatively small. Winds to typhoon force extended out 20 miles (30 km) from the center of Namtheun. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

An upper level trough east of Japan will steer Typhoon Namtheun toward the north-northeast during the weekend. On its anticipated track Namtheun will move toward the Aleutian Islands. Typhoon Namtheun will move into an environment unfavorable for intensification during the weekend. Namtheun will move over much cooler water. The upper level trough east of Japan will produce strong southwesterly winds that will blow toward the top of Namtheun’s circulation. Those winds will cause moderate vertical wind shear. The combination of cooler water and more vertical wind shear will cause Typhoon Namtheun to make a transition to an extratropical cyclone as it moves toward the Aleutian Islands.

Tropical Storm Namtheun Spins Southeast of Japan

Tropical Storm Namtheun was spinning southeast of Japan on Friday morning. At 5:00 a.m. EDT on Friday the center of Tropical Storm Namtheun was located at latitude 26.6°N and longitude 161.9°E which put it about 495 miles (800 km) east-northeast of Minami Tori Shima. Namtheun was moving toward the east-northeast at 18 m.p.h. (29 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 Namtheun was the only current tropical cyclone on Friday morning as it churned over the Western North Pacific Ocean between Japan and Hawaii. Namtheun intensified during the past 24 hours as it moved well to the east of the main islands of Japan. The inner end of a rainband wrapped around the center of Tropical Storm Namtheun. A broken ring of thunderstorms was around the center of circulation. The strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Namtheun. Storms near the core generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 85 miles (135 km) from the center of circulation.

Tropical Storm Namtheun will move through an environment somewhat favorable for intensification during the next 24 hours. Namtheun will move over water where the Sea Surface Temperatures are near 27˚C. An upper level trough southeast of Japan will produce southwesterly winds that will blow toward the top of Namtheun’s circulation. Those winds will cause some vertical wind shear and the wind shear will inhibit intensification. Tropical Storm Namtheun could strengthen during the next 24 hours. Namtheun will move over colder water during the weekend. It will also move in a region where the upper level winds will be stronger. Tropical Storm Namtheun will weaken during the weekend.

The upper level trough southeast of Japan will steer Tropical Storm Namtheun toward the northeast during the next several days. On its anticipated track Namtheun will move farther away from Japan.

Tropical Storm Kompasu Brings Wind and Rain to Northern Luzon

Tropical Storm Kompasu brought wind and rain to northern Luzon on Monday. At 11:00 a.m. EDT on Monday the center of Tropical Storm Kompasu was located at latitude 18.9°N and longitude 120.9°E which put it about 35 miles (55 km) north of Claveria, Philippines. Kompasu was moving toward the west at 16 m.p.h. (26 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 981 mb.

Rainbands in the southern side of Tropical Storm Kompasu brought wind and rain to northern Luzon on Monday. The center of Kompasu passed just north of Luzon. Thunderstorms in bands in southern half of Tropical Storm Kompasu passed over the northern end of Luzon. Kompasu strengthened as it approached northern Luzon. More thunderstorms developed in bands revolving around the center of Tropical Storm Kompasu. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 145 miles (235 km) from the center of Kompasu.

Tropical Storm Kompasu will move through an environment somewhat favorable for intensification during the next 36 hours. Kompasu will move over water where the Sea Surface Temperatures are near 29˚C. It will move south of an upper level ridge over China. The ridge will produce northeasterly winds that will blow toward the top of Kompasu’s circulation. Those winds will cause moderate vertical wind shear and the wind shear will inhibit intensification. Tropical Storm Kompasu is likely to strengthen gradually during the next 24 hours. Kompasu could intensify to a typhoon over the South China Sea.

Tropical Storm Kompasu will move south of a high pressure system over China. The high pressure system will steer Kompasu toward the west during the next several days. On its anticipated track the center of Tropical Storm Kompasu will pass south of Hong Kong in 24 hours. Kompasu could approach Hainan in 36 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Namtheun intensified east of the northern Marianas. At 11:00 a.m. EDT on Monday the center of Tropical Storm Namtheun was located at latitude 19.4°N and longitude 154.0°E which put it about 555 miles (895 km) east of Agrihan. Namtheun was moving toward the west-northwest at 16 m.p.h. (26 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 988 mb.

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.

Dangerous Typhoon Goni Hits Catanduanes

Extremely dangerous Typhoon Goni hit Catanduanes Island on Saturday. At 5:00 p.m. EDT on Saturday the center of Typhoon Goni was located at latitude 13.7°N and longitude 124.4°E which put it about 25 miles (40 km) northeast of Virac, Philippines. Goni was moving toward the west-southwest at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 195 m.p.h. (315 km/h) and there were wind gusts to 235 m.p.h. (380 km/h). The minimum surface pressure was 884 mb.

The eye of Typhoon Goni moved over the southern part of Catanduanes Island on Saturday. Despite the development of concentric eyewalls and the occurrence of an eyewall replacement cycle, Goni actually strengthened on Saturday. The original inner eyewall weakened and the outer eyewall contracted around the center of Typhoon Goni. Goni exhibited an eye with a diameter of 14 miles (22 km) when it made landfall on Catanduanes Island.

The circulation around Typhoon Goni increased in size during the eyewall replacement cycle. Winds to typhoon force extended out 60 miles (95 km) from the center of Goni. Winds to tropical storm force extended out 130 miles (210 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Goni was 48.0. The Hurricane Size Index (HSI) was 16.0 and the Hurricane Wind Intensity Size Index (HWISI) was 64.0. Typhoon Goni was capable of causing catastrophic damage on a regional scale.

Typhoon Goni will also generate a storm surge of up to 20 feet (6 meters) along the coasts of Catanduanes Island and southeastern Luzon. Typhoon Goni will move west across the Philippines. Goni will weaken as the core passes over land. The center of Goni will make landfall in southeastern Luzon near Tabaco. The southern eyewall of Goni will produce strong winds in Legaspi. The northern eyewall will bring strong winds to Naga. Typhoon Goni could be near Manila in 18 hours and it could still be the equivalent of a major hurricane at that time. Goni will also drop locally heavy rain over southern Luzon and flash floods are likely.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Atsani was organizing slowly east of the Philippines. At 5:00 p.m. EDT on Saturday the center of Tropical Storm Atsani was located at latitude 15.2°N and longitude 135.8°E which put it about 900 miles (1450 km) east of Luzon. Atsani 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 1001 mb. Tropical Storm Atsani was forecast to move toward the west and to strengthen.

Potentially Catastrophic Typhoon Goni Nears Luzon

Potentially catastrophic Typhoon Goni neared Luzon on Saturday morning. At 5:00 a.m. EDT on Saturday the center of Typhoon Goni was located at latitude 14.6°N and longitude 126.9°E which put it about 300 miles (485 km) east-northeast of Labo, Philippines. Goni was moving toward the west-southwest at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 180 m.p.h. (290 km/h) and there were wind gusts to 220 m.p.h. (355 km/h). The minimum surface pressure was 898 mb.

Typhoon Goni exhibited a double eyewall structure sometimes seen in very intense tropical cyclones. There was a small inner eye with a diameter of 6 miles (10 km). That eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that inner eyewall. A second, outer eyewall with a diameter of 35 miles (56 km) surrounded the inner core of Typhoon Goni. Storms near the core of Gone generated strong upper level divergence which pumped large quantities of mass away from the typhoon. The removal of so much mass allowed the surface pressure to remain very low. Bands of showers and thunderstorms were revolving around the core of the typhoon.

The circulation around Typhoon Goni increased in size when the double eyewalls formed. Winds to typhoon force extended out 35 miles (55 km) from the center of Goni. Winds to tropical storm force extended out 130 miles (210 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Goni was 42.2. The Hurricane Size Index (HSI) was 13.6 and the Hurricane Wind Intensity Size Index (HWISI) was 55.8. Typhoon Goni was capable of causing catastrophic damage.

Typhoon Goni will move through an environment favorable for a strong typhoon during the next 12 hours. Goni 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. An eyewall replacement cycle could cause Typhoon Goni to start to weaken. If the original inner eyewall dissipates and convergence becomes concentrated into the new outer eyewall, then the wind speed will decrease. However, Goni is likely to maintain much of its intensity until it reaches Luzon.

Typhoon Goni will move south of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Goni toward the west. On its anticipated track Typhoon Goni will be near Cataduanes Island in 12 48 hours. Goni could be near Manila in 24 hours. Typhoon Goni is capable of causing catastrophic damage to Luzon. Goni could generate a storm surge of up to 20 feet (6 meters) along the coast of southeastern Luzon. Typhoon Goni will drop heavy rain over parts of Luzon and flash floods are likely.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Atsani moved north of Yap. At 5:00 a.m. EDT on Saturday the center of Tropical Storm Atsani was located at latitude 14.6°N and longitude 138.2°E which put it about 1060 miles (1705 km) east of Luzon. Astani was moving toward the west at 17 m.p.h. (28 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. Tropical Storm Atsani was forecast to move toward the northwest and to strengthen.

Typhoon Goni Rapidly Intensifies Into Equivalent of Cat. 5 Hurricane

Typhoon Goni intensified rapidly into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale east of the Philippines on Thursday night. At 5:00 a.m. EDT on Friday the center of Typhoon Goni was located at latitude 16.2°N and longitude 131.2°E which put it about 620 miles (1000 km) east of Luzon. Goni was moving toward the west at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 205 m.p.h. (330 km/h). The minimum surface pressure was 912 mb. Typhoon Goni is capable of causing catastrophic damage.

Typhoon Goni continued to intensify rapidly on Thursday night. A small circular eye with a diameter of 10 miles (16 km) was at the center of Goni. 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 tight core of Typhoon Goni. Storms near the core generated strong upper level divergence which pumped mass away from the typhoon. The removal of mass allowed the surface pressure to decrease quickly which contributed to the rapid increase in wind speed.

Typhoon Goni will move through an environment favorable for a strong typhoon during the next 36 to 48 hours. Goni 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, then an eyewall replacement cycle could occur. The cycle would cause Goni to weaken when the original inner eyewall dissipates and convergence becomes concentrated into a new outer eyewall. An eyewall replacement cycle would also cause the size of the circulation around Goni to Increase.

Typhoon Goni will move south of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Goni toward the west. On its anticipated track Typhoon Goni will approach the coast of Luzon in about 48 hours. Goni is likely to be the equivalent of a major hurricane when it approaches Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Atsani moved south of the Marianas. At 5:00 a.m. EDT on Friday the center of Tropical Storm Atsani was located at latitude 11.6°N and longitude 142.6°E which put it about 170 miles (275 km) south-southwest of Guam. Astani was moving toward the west-northwest at 30 m.p.h. (48 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. Tropical Storm Atsani was forecast to move toward the northwest and to strengthen.

Typhoon Goni Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Goni intensified rapidly into the equivalent of a major hurricane east of the Philippines on Thursday. At 11:00 p.m. EDT on Thursday the center of Typhoon Goni was located at latitude 16.2°N and longitude 132.2°E which put it about 690 miles (1115 km) east of Luzon. Goni was moving toward the west at 7 m.p.h. (11 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 934 mb.

Typhoon Goni intensified rapidly on Thursday. A small circular eye with a diameter of 12 miles (19 km) was at the center of Goni. 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 Goni. Storms near the core generated strong upper level divergence which pumped mass away from the typhoon. The removal of mass allowed the surface pressure to decrease quickly which contributed to the rapid increase in wind speed.

The circulation around Typhoon Goni was small. Winds to typhoon force extended out 25 miles (40 km) from the center of Goni. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Goni was 29.9. The Hurricane Size Index (HSI) was 6.3 and the Hurricane Wind Intensity Size Index (HWISI) was 36.2.

Typhoon Goni will move through an environment favorable for intensification during the next 24 hours. Goni 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. Goni could intensify more during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause Goni to weaken.

Typhoon Goni will move south of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Goni toward the west. On its anticipated track Typhoon Goni will approach the coast of Luzon in about 48 hours. Goni is likely to be the equivalent of a major hurricane when it approaches Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Atsani moved south-southeast of the Marianas. At 11:00 p.m. EDT on Thursday the center of Tropical Storm Atsani was located at latitude 10.7°N and longitude 145.3°E which put it about 245 miles (400 km) south-southeast of Guam. Astani was moving toward the northwest at 18 m.p.h. (30 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. Tropical Storm Atsani was forecast to move toward the northwest and to strengthen.

Goni Rapidly Intensifies to a Typhoon, Atsani Forms

Former Tropical Storm Goni intensified rapidly into a typhoon east of the Philippines on Thursday and Tropical Storm Atsani formed south-southeast of the Marianas. At 11:00 a.m. EDT on Thursday the center of Typhoon Goni was located at latitude 16.7°N and longitude 134.1°E which put it about 820 miles (1320 km) east of Luzon. Goni was moving toward the west at 14 m.p.h. (22 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 973 mb.

Typhoon Goni intensified rapidly on Thursday. A small circular eye was at the center of Goni. 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 Goni. Storms near the core generated strong upper level divergence which pumped mass away from the typhoon. The removal of mass allowed the surface pressure to decrease quickly which contributed to the rapid increase in wind speed. The circulation around Typhoon Goni was small. Winds to typhoon force extended out 20 miles (30 km) from the center of Goni. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation.

Typhoon Goni will move through an environment favorable for intensification during the next several days. Goni 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. Goni could intensify into the equivalent of a major hurricane during the next 24 hours.

Typhoon Goni will move south of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Goni toward the west. On its anticipated track Typhoon Goni will approach the coast of Luzon in about 72 hours. Goni is likely to be the equivalent of a major hurricane when it approaches Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Atsani formed south-southeast of the Marianas. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Atsani was located at latitude 8.7°N and longitude 148.0°E which put it about 450 miles (720 km) south-southeast of Guam. Astani was moving toward the north-northwest 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 1001 mb. Tropical Storm Atsani was forecast to move toward the northwest and to strengthen.

Tropical Cyclone Bulbul Makes Landfall Southeast of Kolkata

Tropical Cyclone Bulbul made landfall southeast of Kolkata, India on Saturday.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Bulbul was located at latitude 21.8°N and longitude 89.2°E which put it about 75 miles (120 km) southeast of Kolkata, India.  Bulbul was movign toward the east-northeast at 9 m.p.h. (15 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 967 mb.

Tropical Cyclone Bulbul made landfall on the coast of West Bengal southeast of Kolkata, India on Saturday.  The India Meteorological Department’s weather radar in Kolkata indicated that the eye of Bulbul crossed the coast of West Bengal.  Tropical Cyclone Bulbul was the equivalent of a hurricane/typhoon at the time of landfall.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center.

The northern section of the eyewall of Tropical Cyclone Bulbul moved across the southeastern part of West Bengal and the southwestern portion of Bangladesh.  Thunderstorms in the eyewall were dropping heavy rain over those areas.  Bands of showers and thunderstorms in the northeastern part of Bulbul were also dropping heavy rain over other parts of Bangladesh.  The heavy rain could cause floods in some locations.  Southerly winds blowing around the eastern side of Tropical Cyclone Bulbul were pushing water toward the coast.  Bulbul could cause a storm surge of 6 to 9 feet (2 to 3 meters) in some coastal locations.

Tropical Cyclone Bulbul will move around the northwestern part of a ridge of high pressure over southeast Asia.  The ridge will steer Bulbul toward the east-northeast during the next several days.  On its anticipated track Tropical Cyclone Bulbul will move over coastal areas of Bangladesh between Dhaka and Chittagong.  Bulbul will weaken gradually as the center moves over land.  The wind speeds and storm surges will gradually decrease.  Tropical Cyclone Bulbul will continue to drop heavy rain over southern Bangladesh during the next 24 hours and the threat of fresh water floods will remain.