Category Archives: Western North Pacific

Western Pacific Typhoons and Tropical Storms

Pakhar Weakens to a Tropical Depression

Former Tropical Storm Pakhar weakened to a tropical depression over the Western North Pacific Ocean northeast of the Philippines on Monday. At 4:00 p.m. EST on Monday the center of Tropical Depression Pakhar was located at latitude 19.3°N and longitude 131.1°E which put it about 745 miles (1205 km) east-northeast of Manila, Philippines. Pakhar was moving toward the southeast at 7 m.p.h. (21 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.

After strengthening on Sunday, former Tropical Storm Pakhar weakened to a tropical depression on Monday. An upper level trough west of Japan produced strong southwesterly winds that blew across the top of Pakhar’s circulation. Those winds caused strong vertical wind shear and they blew the top of former Tropical Storm Pakhar away to the northeast of the lower level circulation. The circulation around Tropical Depression Pakhar on Monday afternoon consisted of a swirl of showers and lower clouds. Any clouds that grew higher into the atmosphere were quickly sheared apart by the strong upper level winds.

The circulation around Tropical Depression Pakhar will spin down gradually during the next 24 hours. Pakhar will move over water where the Sea Surface Temperatures are near 28˚C. However, the upper level trough west of Japan will continue to cause strong vertical wind shear. The wind shear will prevent the development of new thunderstorms around Tropical Depression Pakhar.

Since the circulation around Tropical Depression Pakhar only exists in the lower levels of the atmosphere, it will be steered by the winds near the surface. Northeasterly winds will push Pakhar back toward the southwest. On its anticipated track, the circulation around Tropical Depression Pakhar should dissipate east of the Philippines during the next 48 hours.

Tropical Storm Pakhar Develops Northeast of the Philippines

Tropical Storm Pakhar developed over the Western North Pacific Ocean northeast of the Philippines on Sunday. At 10:00 a.m. EST on Sunday the center of Tropical Storm Pakhar was located at latitude 18.5°N and longitude 127.5°E which put it about 470 miles (755 km) east-northeast of Manila, Philippines. Pakhar was moving toward the northeast at 13 m.p.h. (20 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.

The circulation around a low pressure system northeast of the Philippines strengthened on Sunday and the Japan Meteorological Agency designated the system as Tropical Storm Pakhar. More thunderstorms developed near the center of Pakhar’s circulation. Bands of showers and thunderstorms were revolving around the center of Tropical Storm Pakhar. Storms near the center of Pakhar generated upper level divergence that pumped mass away to the northeast of the tropical storm. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation.

Tropical Storm Pakhar will move through an environment favorable for intensification during the next 18 hours. Pakhar will move over water where the Sea Surface Temperatures are near 28˚C. An upper level trough east of China will produce southwesterly winds that will blow toward the top of Pakhar’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification, but Tropical Storm Pakhar could strengthen during the next 18 hours. The upper level trough will move closer to Pakhar on Monday and the upper level winds will get stronger. More vertical wind shear will cause Tropical Storm Pakhar to weaken early next week.

The upper level trough over eastern China will steer Tropical Storm Pakhar toward the northeast during the next 24 hours. On its anticipated track, Pakhar will move farther away from the Philippines. When the vertical wind shear increases on Monday, strong upper level winds could blow the top off of Tropical Storm Pakhar. If that happens, then Pakhar will be steered by winds in the lower levels of the atmosphere. Those winds could steer Pakhar back toward the southwest early next week.

Tropical Storm Yamaneko Moves North of Wake Island

Tropical Storm Yamaneko moved north of Wake Island on Sunday. At 4:00 p.m. EST on Sunday the center of Tropical Storm Yamaneko was located at latitude 23.4°N and longitude 166.0°E which put it about 245 miles (395 km) north of Wake Island. Yamaneko was moving toward the north 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 1000 mb.

Tropical Storm Yamaneko moved farther north of Wake Island on Sunday. The distribution of thunderstorms in Yamaneko was asymmetrical. Thunderstorms were occurring in bands in the far eastern part of Tropical Storm Yamaneko. Bands in the rest of Yamaneko’s circulation consisted primarily of showers and lower clouds. An upper level trough southeast of Japan was producing strong southwesterly winds that were blowing across the top of Tropical Storm Yamaneko. Those winds were causing strong vertical wind shear. The strong vertical wind shear was causing the upper part of Yamaneko’s circulation to tilt toward the northeast. The strong upper level winds were also blowing off the tops of thunderstorms that started to form near the center of Yamaneko and in the western part of the circulation.

Tropical Storm Yamaneko will move through an environment that will cause it to make a transition to an extratropical cyclone during the next 36 hours. Yamaneko will move over water where the Sea Surface Temperatures are colder than 26˚C. The upper level trough southeast of Japan will continue to cause strong vertical wind shear. A combination of cooler water and strong vertical wind shear will cause Tropical Storm Yamaneko to make a transition to an extratropical cyclone.

The upper level trough will steer Tropical Storm Yamaneko toward the north-northeast during the next 36 hours. On its anticipated track, Tropical Storm Yamaneko will pass far to the west of Midway Island in 24 hours.

Tropical Storm Yamaneko Forms Northwest of Wake Island

Tropical Storm Yamaneko formed over the Western North Pacific Ocean northwest of Wake Island on Saturday afternoon. At 4:00 p.m. EST on Saturday the center of Tropical Storm Yamaneko was located at latitude 22.0°N and longitude 165.7°E which put it about 180 miles (295 km) north-northwest of Wake Island. Yamaneko was moving toward the north-northeast 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 1000 mb.

An area of low pressure over the Western North Pacific Ocean northwest of Wake Island strengthened on Saturday afternoon and the Japan Meteorological Agency designated the system as Tropical Storm Yamaneko. Thunderstorms near the center of circulation generated upper level divergence that pumped mass away to the east of the tropical storm. The inner end of a rainband wrapped around the northern and western side of the center of Yamaneko’s circulation. Other bands of thunderstorms were in the eastern half of Tropical Storm Yamaneko. Many of the bands in the western side of Yamaneko consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 130 miles (210 km) in the eastern side of Tropical Storm Yamaneko. The winds in the western side of Yamaneko were blowing at less than tropical storm force.

Tropical Storm Yamaneko will move through an environment somewhat favorable for intensification during the next 24 hours. Yamaneko 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 Yamaneko’s circulation. Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but the shear will not be enough to prevent Yamaneko from getting a little stronger. Tropical Storm Yamaneko is likely to intensify gradually during the next 24 hours.

The upper level trough southeast of Japan will steer Tropical Storm Yamaneko toward the north during the next 24 hours. On its anticipated track, Tropical Storm Yamaneko will move farther away from Wake Island.

Nalgae Strengthens to a Typhoon South-Southeast of Hong Kong

Former Tropical Storm Nalgae strengthened to a typhoon over the South China Sea south-southeast of Hong Kong on Monday. At 11:00 a.m. EDT on Monday the center of Typhoon Nalgae was located at latitude 18.2°N and longitude 116.3°E which put it about 310 miles (500 km) south-southeast of Hong Kong. Nalgae was moving toward the north-northwest at 8 m.p.h. (13 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 981 mb.

Typhoon Nalgae strengthened gradually over the South China Sea south-southeast of Hong Kong on Monday. A large eye with a diameter of 30 miles (50 km) formed at the center of Nalgae’s circulation. A broken ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Typhoon Nalgae. Storms near the center of circulation generated upper level divergence that pumped mass away from the typhoon. Winds to typhoon force extended out 20 miles (30 km) in the western side of Nalgae. Winds to tropical storm force extended out 330 miles (515 km) from the center of circulation.

Typhoon Nalgae will move through an environment mostly favorable for intensification during the next 24 hours. Nalgae will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western side of an upper level ridge over the Western North Pacific. The upper level ridge will produce southerly winds that will blow toward the top of Nalgae’s circulation. Those winds will cause vertical wind shear, but the wind shear will not be strong enough to prevent intensification. Typhoon Nalgae is likely to intensify during the next 24 hours. Nalgae will move into an environment where there is drier air in the lower levels of the atmosphere when it moves closer to China. Typhoon Nalgae will weaken when the drier air gets pulled into its circulation.

Typhoon Nalgae will move around the western end of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Nalgae toward the northwest during the next 24 hours. On its anticipated track Typhoon Nalgae will move closer to Hong Kong during the next 24 hours. Nalgae will move more toward the west when it encounters the drier environment near China and weakens.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Banyan developed east of the Philippines. At 11:00 a.m. EDT on Monday the center of Tropical Storm Banyan was located at latitude 7.3°N and longitude 131.2°E which put it about 320 miles (515 km) east of Mindanao. Banyan was moving toward the west-northwest at 11 m.p.h. (17 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1000 mb.

Tropical Storm Nalgae Causes Floods and Mudslides in the Philippines

Tropical Storm Nalgae caused floods and mudslides in the Philippines on Saturday. At 5:00 p.m. EDT on Saturday the center of Tropical Storm Nalgae was located at latitude 15.9°N and longitude 119.8°E which put it about 100 miles (160 km) north-northwest of Manila, Philippines. Nalgae was moving toward the northwest at 15 m.p.h. (24 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 Nalgae dropped heavy rain as it moved across Luzon on Saturday. Heavy rain caused floods and mudslides in some locations. There were reports of deaths and injuries that were caused by the floods and mudslides. Tropical Nalgae did weaken as it moved across Luzon, but some bands were still dropping heavy rain in places. The center of Nalgae was about to move over the South China Sea. Winds to tropical storm force extended out 175 miles (280 km) from the center of Nalgae’s circulation.

Tropical Storm Nalgae will move through an environment mostly favorable for intensification during the next 36 hours. Nalgae will move over water where the Sea Surface Temperatures are near 29˚C. Nalgae will move under the western side of an upper level ridge over the Western North Pacific. The upper level ridge will produce southerly winds that will blow toward the top of Nalgae’s circulation. Those winds will cause vertical wind shear, but the wind shear will not be strong enough to prevent intensification. Tropical Storm Nalgae is likely to intensify when it move over the South China Sea. Nalgae could strengthen to a typhoon during the next 36 hours.

Tropical Storm Nalgae will move around the western end of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Nalgae toward the northwest during the next 36 hours. On its anticipated track Tropical Storm Nalgae will move away from northern Luzon. The heavy rain in the Philippines will diminish when Nalgae moves farther away from Luzon.

Tropical Storm Nalgae Brings Wind and Rain to the Philippines

Tropical Storm Nalgae brought wind and rain to the Philippines on Friday. At 5:00 p.m. EDT on Friday the center of Tropical Storm Nalgae was located at latitude 14.3°N and longitude 123.1°E which put it about 175 miles (280 km) east of Manila, Philippines. Nalgae was moving toward the west-northwest at 22 m.p.h. (35 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 Nalgae strengthened on Friday as it approached southeastern Luzon. The inner end of a rainband wrapped around the eastern side of the center of Nalgae. Bands of showers and thunderstorms were revolving around the core of Tropical Storm Nalgae. Storms near the core generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 200 miles (320 km) from the center of Nalgae.

Tropical Storm Nalgae will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Nalgae toward the west-northwest during the next 24 hours. On its anticipated track Tropical Storm Nalgae will move quickly across Luzon. Nalgae will continue to produce gusty winds and locally heavy rain in Luzon during the next 24 hours. Heavy rain is likely to cause flash floods in some locations.

Tropical Storm Nalgae will move through an environment mostly favorable for intensification during the next 36 hours. When the center of Nalgae is over water, it will move over water where the Sea Surface Temperatures are near 29˚C. An upper level ridge over the Western North Pacific will produce northeasterly winds that will blow toward the top of Nalgae’s circulation. Those winds will cause vertical wind shear, but the wind shear will not be strong enough to prevent intensification. Tropical Storm Nalgae will be unlikely to intensify while the center of its circulation is over Luzon. Nalgae could intensify when the center moves over the South China Sea.

Tropical Storm Nalgae Forms East of the Philippines

Tropical Storm Nalgae formed over the Western North Pacific Ocean east of the Philippines on Thursday. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Nalgae was located at latitude 12.2°N and longitude 129.7°E which put it about 410 miles (660 km) east of Legazpi, Philippines. Nalgae was moving toward the west at 6 m.p.h. 105 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1000 mb.

An area of low pressure over the Western North Pacific Ocean east of the Philippines strengthened on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Nalgae. The distribution of thunderstorms around Tropical Storm Nalgae was asymmetrical. Thunderstorms were occurring in bands in the southern half of Nalgae’s circulation. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. Tropical Storm Nalgae was moving under the southern part of an upper level ridge over the Western North Pacific. The ridge was producing northeasterly winds that were blowing toward the top of Nalgae’s circulation. Those winds were causing moderate vertical wind shear and the wind shear was causing the asymmetrical distribution of thunderstorms.

Tropical Storm Nalgae will move through an environment favorable for intensification during the next 36 hours. Nalgae will move over water where the Sea Surface Temperatures are near 29˚C. The upper level ridge over the Western North Pacific will continue to cause moderate vertical wind shear. However, the wind shear will not be strong enough to prevent intensification. Tropical Storm Nalgae will intensify during the next 36 hours. It is forecast to strengthen to a typhoon.

Tropical Storm Nalgae will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Nalgae toward the west-northwest during the next 36 hours. On its anticipated track Tropical Storm Nalgae will approach southeastern Luzon on Friday. Nalgae could be a typhoon when it reaches southeast Luzon. It could bring strong winds and locally heavy rain. Heavy rain is likely to cause flash floods in some locations.

Tropical Storm Nesat Drops Rain on Hainan

Tropical Storm Nesat dropped rain on Hainan on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Nesat was located at latitude 17.0°N and longitude 110.5°E which put it about 100 miles (160 km) south-southeast of Lingshui China. Nesat was moving toward the west at 12 m.p.h. (19 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.

Former Typhoon Nesat weakened to a tropical storm on Tuesday as it moved over the South China Sea southeast of Hainan. An upper level ridge over China produced easterly winds that blew toward the top of Nesat’s circulation. Those winds caused moderate vertical wind shear and the wind shear caused an asymmetrical distribution of thunderstorms around Tropical Storm Nesat. Most of the thunderstorms were occurring in the northwestern part of Nesat. Those thunderstorms dropped heavy rain over Hainan and parts of southern China. Winds to tropical storm force extended out 200 miles (320 km) from the center of Nesat.

Tropical Storm Nesat will move through an environment unfavorable for intensification during the next 48 hours. Nesat will move over water where the Sea Surface Temperatures are near 29˚C. It will continue to move under the southern part of the over China. The ridge will produce easterly winds that will cause moderate vertical wind shear and the wind shear will inhibit intensification. A surface high pressure system over southern China will produce northeasterly winds that will transport drier air into the northern and western parts of Tropical Storm Nesat. The vertical wind shear and the drier air will cause Tropical Storm Nesat to continue to weaken during the next 48 hours.

The surface high pressure system over southern China will steer Tropical Storm Nesat toward the west during the next 48 hours. On its anticipated track, the center of Tropical Storm Nesat will pass south of Hainan during the next 24 hours. Nesat could approach the coast of Vietnam in 36 hours. Bands on the northern side of Tropical Storm Nesat will drop locally heavy rain on parts of Hainan, southern China and northern Vietnam. Heavy rain could cause flash floods in some locations.

Typhoon Nesat Passes South of Hong Kong

Typhoon Nesat passed south of Hong Kong as it moved across the South China Sea on Monday night. At 11:00 p.m. EDT on Monday the center of Typhoon Nesat was located at latitude 18.0°N and longitude 113.3°E which put it about 285 miles (460 km) south of Hong Kong. Nesat was moving toward the west-southwest at 12 m.p.h. (19 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 971 mb.

Typhoon Nesat started to weaken on Monday night as it passed south of Hong Kong. A circular eye was still present at the center of Nesat’s circulation. However a break occurred in the southeastern part of the ring of thunderstorms surrounded the eye of Typhoon Nesat. The strongest winds were occurring in the broken ring of thunderstorms. Bands of showers and thunderstorms were occurring in the western half of Nesat. Bands in the eastern side of the circulation consisted primarily of showers and lower clouds. Storms near the center of Nesat generated upper level divergence that pumped mass away to the west of the typhoon.

The circulation around Typhoon Nesat interacted with a large surface high pressure system over southern China to produce a large area of tropical storm force winds in the northern part of Nesat’s circulation. Winds to tropical storm force extended out 400 miles (640 km) in the northern side of Typhoon Nesat. Winds to tropical storm force extended out 120 miles (195 km) in the southern side of Nesat. Winds to typhoon force extended out 40 miles (65 km) from the center of circulation.

Typhoon Nesat will move through an environment unfavorable for intensification during the next 48 hours. Nesat will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the southern part of an upper level ridge that extends over the Western North Pacific Ocean to southern China. The ridge will produce easterly winds that will cause moderate vertical wind shear and the wind shear will inhibit intensification. The surface high pressure system over southern China will produce northeasterly winds that will transport drier air into the northern and western parts of Typhoon Nesat. The vertical wind shear and the drier air will cause Typhoon Nesat to weaken during the next 48 hours.

The surface high pressure system over southern China will steer Typhoon Nesat toward the west during the next 48 hours. On its anticipated track, Typhoon Nesat will pass south of Hainan in 36 hours. Nesat is likely to weaken to a tropical storm by the time it passes south of Hainan. Nesat could bring gusty winds and locally heavy rain to Hainan on Tuesday night and Wednesday.