Category Archives: Western North Pacific

Western Pacific Typhoons and Tropical Storms

Tropical Storm Fung-wong Nears Southern Ryukyu Islands

Tropical Storm Fung-wong neared the southern Ryukyu Islands on Thursday night.  At 10:00 p.m. EDT on Thursday the center of Tropical Storm Fung-wong was located at latitude 23.3°N and longitude 124.9°E which put it about 110 miles (175 km) south-southwest of Harari, Japan.  Fung-wong was moving toward the north-northeast at13 m.p.h. (20 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 989 mb.

Tropical Storm Fung-wong was weakening gradually as it neared the southern Ryukyu Islands.  An upper level trough over east Asia was producing southwesterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear.  There was still a well defined low level center of circulation.  A broken ring of thunderstorms surrounded the center and the strongest winds were occurring near the center of Fung-wong.  Most of the stronger thunderstorms were occurring in bands north and east of the center of circulation.  Bands in the southern and western parts of the tropical storm consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 120 miles (195 km) from the center of circulation.

A high pressure system over the Western North Pacific Ocean and the trough over east Asia will interact to steer Tropical Storm Fung-wong toward the north-northeast during the next 24 to 36 hours.  On its anticipated track Fung-wong will move over the southern Ryukyu Islands during the next 24 hours.  The center of the tropical storm could pass close to Miyako Jima in about 12 hours.  Tropical Storm Fung-wong will continue to weaken gradually because of the moderate vertical wind shear.  Fung-wong will bring gusty winds and locally heavy rain to some of the southern Ryukyu Islands.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Kalmaegi was moving across the South China Sea toward Vietnam.  At 10:00 p.m. EST on Thursday the center of Tropical Depression Kalmaegi was located at latitude 11.5°N and longitude 114.5°E which put it about 550 miles (890 km) east of Ho Chi Minh City, Vietnam.  Kalmaegi was moving toward the west-southwest at 11 m.p.h. (17 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 1004 mb.  Tropical Depression Kalmaegi could drop locally heavy rain over parts of southern Vietnam during the weekend.

Tropical Storm Kalmaegi Brings Wind and Rain to Northern Luzon

Tropical Storm Kalmaegi brought wind and rain to northern Luzon on Tuesday night.  At 10:00 p.m. EST on Tuesday the center Tropical Storm Kalmaegi was located at latitude 17.0°N and longitude 121.2°W which put it about 70 miles (110 km) northeast of Baguio, Philippines.  Kalmaegi was moving toward the south-southwest at 15 m.p.h. (24 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 987 mb.

Former Typhoon Kalmaegi weakened to a tropical storm before it made landfall on the north coast of Luzon near Aparri.  Kalmaegi was under the western end of an upper level ridge.  The ridge produced strong southerly winds which blew toward the top of the circulation.  Those winds caused moderate vertical wind shear which weakened thunderstorms in the southern half of the circulation.  Drier air from Asia was pulled into the western part of the tropical storm.  The stronger thunderstorms were occurring northeast of the center of circulation.  Winds to tropical storm force extended out 100 miles (160 km) from the center in most parts of Tropical Storm Kalmaegi.  A high pressure system over Asia was contributing to a bigger pressure gradient in the northwestern quadrant of Kalmaegi and winds to tropical storm force extended out 200 miles (320 km) in that area.

Tropical Storm Kalmaegi was dropping locally heavy rain over parts of northern Luzon.  The heavy rain was creating the potential for flash floods.  Kalmaegi will be steered toward the southwest by the high pressure system over Asia. On its anticipated track the center of Tropical Storm Kalmaegi will pass near Baguio.  Kalmaegi will continue to weaken as it moves over northern Luzon.  It will move over the South China Sea northwest of Manila.  Tropical Storm Kalmaegi will continue to drop heavy rain over parts of Luzon and the flash flood threat will continue for several more days.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Fung-wong developed east of Luzon on Tuesday night.  At 10:00 p.m. EST the center of Tropical Storm Fung-wong was located at latitude 16.3°N and longitude 127.8°E which put it about 425 miles (685 km) east-southeast of Aparri, Philippines.  Fung-wong was moving toward the 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 1000 mb.  Tropical Storm Fung-wong is forecast to strengthen during the next 36 hours while it moves toward the Luzon Strait.

Tropical Storm Kalmaegi Almost a Typhoon Near Northern Luzon

Tropical Storm Kalmaegi was almost a typhoon as it neared northern Luzon on Sunday night.  At 10:00 p.m. EST on Sunday the center of Tropical Storm Kalmaegi was located at latitude 17.7°N and longitude 123.2°E which put it about 120 miles (195 km) east-southeast of Aparri, Philippines.  Kalmaegi was moving toward the northwest at 6 m.p.h. (10 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 984 mb.

Tropical Storm Kalmaegi was on the verge of strengthening into a typhoon on Sunday night.  The inner end of a band of showers and thunderstorms wrapped most of the way around the center of circulation and an eye appeared to be forming.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Kalmaegi.  Storms near the center were generating upper level divergence which was pumping mass away to the northeast of the tropical storm.  Winds to tropical storm force extended out 110 miles (175 km) from the center of circulation.

Tropical Storm Kalmaegi will move through an environment favorable for intensification for anther 12 to 24 hours.  Kalmaegi will move over water where the Sea Surface Temperature is near 29°C.  It will move under the western end of an upper level ridge.  The ridge will produce southerly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Storm Kalmaegi is likely to strengthen into a typhoon on Monday.

A ridge of high pressure will steer Tropical Storm Kalmaegi toward the northwest during the next 12 to 24 hours.  On its anticipated track the center of Tropical Storm Kalmaegi will make a landfall on the north coast of Luzon near Aparri in about 24 hours.  Kalmaegi will weaken after the center moves over land.  When Tropical Storm Kalmaegi weakens a strong northeasterly flow in the lower levels will steer the tropical storm back toward the southwest.  Tropical Storm Kalmaegi will bring gusty winds and it will drop locally heavy rain over northern Luzon.  Heavy rain could cause flash floods in some locations.

Tropical Storm Kalmaegi Strengthens East of Luzon

Tropical Storm Kalmaegi strengthened east of Luzon on Saturday night.  At 10:00 p.m. EST on Saturday the center of Tropical Storm Kalmaegi was located at latitude 15.7°N and longitude 125.2°E which put it about 300 miles (185 km) east-southeast of Aparri, Philippines.  Kalmaegi was moving toward the west-northwest at 5 m.p.h. (8 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 996 mb.

After meandering for days east of Luzon, Tropical Storm Kalmaegi began to strengthen on Saturday night.  Bands of showers and thunderstorms strengthened and wrapped around the eastern and northern sides of the center of circulation.   Storms near the center began to generate upper level divergence which pumped mass away to the northeast of the tropical storm.  Bands in the western half of the circulation still consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 120 miles (195 km) from the center.

Tropical Storm Kalmaegi will move through an environment favorable for intensification during the next 24 to 36 hours.  Kalmaegi will move over water where the Sea Surface Temperature is near 29°C.  It will move south of an upper level ridge over the Western North Pacific Ocean.  The ridge will produce easterly winds which will cause some vertical wind shear.  The shear will slow the rate of intensification, but it will not be strong enough to prevent intensification.  Tropical Storm Kalmaegi could strengthen into a typhoon during the next 36 hours.

The ridge over the Western Pacific Ocean will steer Tropical Storm Kalmaegi toward the northwest during the next 36 hours.  On its anticipated track Tropical Storm Kalmaegi could approach northern Luzon in about 36 hours.  Kalmaegi could be a typhoon by that time.

Elsewhere over the Western North Pacific Ocean, Typhoon Fengshen was speeding away from Iwo To.  At 10:00 p.m. EST on Saturday the center of Typhoon Fengshen was located at latitude 26.4°N and longitude 153.1°E which put it about 690 miles (1110 km) east-northeast of Iwo To.  Fengshen was moving toward the east at 31 m.p.h. (50 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 962 mb.

Typhoon Fengshen Strengthens into Equivalent of a Major Hurricane

Typhoon Fengshen strengthened into the equivalent of a major hurricane on Friday.  At 4:00 p.m. EST on Friday the center of Typhoon Fengshen was located at latitude 23.0°N and longitude 142.9°E which put it about 175 miles (285 km) south-southeast of Io To.  Fengshen was moving toward the north at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 949 mb.

Typhoon Fengshen strengthened quickly into the equivalent of a major hurricane on Friday.  An eye with a diameter of 25 miles (40 km) developed at the center of Fengshen.  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 Fengshen.  Storms near the core were generating strong upper level divergence which was pumping mass away to the northeast of the typhoon.

The circulation around Typhoon Fengshen increased in size on Friday.  Winds to typhoon force extended out 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out 140 miles (225) km from the center.  The Hurricane Intensity Index (HII) for Typhoon Fengshen was 23.6.  The Hurricane Size Index (HSI) was 11.2 and the Hurricane Wind Intensity Size Index (HWISI) was 34.8.

Typhoon Fengshen may have reached its peak intensity.  Fengshen will move over water where the Sea Surface Temperature is near 28°C.  So, there will be suffiicient energy in the upper levels of the Western Pacific to support intensification.  However, a large upper level trough southwest of Japan will move toward Fengshen.  The trough will produce strong southwesterly winds which will blow toward the top of the typhoon.  Those winds will cause moderate to strong vertical wind shear and the shear will cause Typhoon Fengshen to being to weaken.

A ridge of high pressure east of Typhoon Fengshen and the upper level trough southwest of Japan will interact to steer the typhoon toward the northeast during the weekend.  On its anticipated track the core of Typhoon Fengshen which contains the strongest winds will pass southeast of Iwo To.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Kalmaegi moved very slowly toward northern Luzon.  At 4:00 p.m. EST on Friday the center of Tropical Storm Kalmaegi was located at latitude 16.0°N and longitude 125.9°E which put it about 345 miles (555 km) southeast of Aparri, Philippines.  Kalmaegi was moving toward the west at 2 m.p.h. (3 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.

Typhoon Fengshen Brings Wind and Rain to Northern Marianas

Typhoon Fengshen brought wind and rain to the Northern Marianas on Thursday.  At 10:00 p.m. EST on Thursday the center of Typhoon Fengshen was located at latitude 19.6°N and longitude 143.3°E which put it about 385 miles (620 km) south-southeast of Iwo To.  Fengshen was moving toward the northwest at 18 m.p.h. (30 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 974 mb.

Typhoon Fengshen intensified rapidly into a typhoon on Thursday as it moved over the Northern Marianas.  Fengshen brought strong, gusty winds and heavy rain to Alamagan, Agrihan and Pagan.  There was a small circular eye at the center of Typhoon Fengshen.  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 Fengshen.  Storms near the core were generating upper level divergence which was pumping mass away from the typhoon.  Winds to typhoon force extended out 30 miles from the center of circulation.  Winds to tropical storm force extended out 85 miles (135 km) from the center.

Typhoon Fengshen will move through an environment favorable for intensification during the next day or so.  Fengshen will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Fengshen could strengthen into the equivalent of a major hurricane on Friday.

Typhoon Fengshen will move around the western end of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Fengshen toward the north during the next 24 hours.  The typhoon will move toward the northeast on Saturday after it moves around the end of the ridge.  On its anticipated track Typhoon Fengshen will be south of Iwo To in about 24 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Kalmaegi move closer to northern Luzon.  At 10:00 p.m. EST on Thursday the center of Tropical Storm Kalmaegi was located at latitude 16.6°N and longitude 125.0°E which put it about 250 miles (400 km) southeast of Aparri, Philippines.  Kalmaegi was moving toward the west-northwest at 12 m.p.h. (19 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 Fengshen Prompts Typhoon Warning for Northern Marianas

Tropical Storm Fengshen prompted the National Weather Service Office in Guam to issue a Typhoon Warning for portions of the Northern Marianas on Wednesday night.  At 10:00 a.m. EST on Wednesday the center of Tropical Storm Fengshen was located at latitude 17.2°N and longitude 149.0°E which put it about 265 miles (430 km) east of Alamagan.  Fengshen was moving toward west at 18 m.p.h. (30 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. (129 km/h).  The minimum surface pressure was 991 mb.

A Typhoon Warning was in effect for Alamagan, Pagan and Agrihan.

Tropical Storm Fengshen strengthened slowly on Wednesday, although the thunderstorm activity fluctuated during the day.  More thunderstorms developed near the center of circulation on Wednesday night.  Those thunderstorms were generating some upper level divergence which was pumping mass away to the west of the tropical storm.  The strongest rainbands were in the southern and eastern parts of Fengshen.  Bands in the northern wand western parts of the circulations consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation.

The circulation around Tropical Storm Fengshen may have pulled drier air into the tropical storm.  The drier air may have mixed into rainbands in the northern and western parts of Fengshen and caused the thunderstorms in those parts of the tropical storm to weaken.  Tropical Storm Fengshen will move through an environment favorable for intensification during the next several days.  Fengshen will move over water where the Sea Surface Temperature is near 29°C.  It will move south of an upper level ridge centered south of Japan.  The ridge will produce northeasterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear.  The wind shear and drier air will slow the rate of intensification.  Tropical Storm Fengshen could strengthen into a typhoon within 24 hours.

The ridge south of Japan will steer Tropical Storm Fengshen toward the west for another 12 to 24 hours.  Fengshen will start to move toward the north when it reaches the western end of the ridge.  On its anticipated track Tropical Storm Fengshen could reach Alamagan, Pagan and Agrihan in about 12 hours.  Fengshen could be a typhoon at that time.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Kalmaegi moved slowly toward northern Luzon.  At 10:00 p.m. EST on Wednesday the center of Tropical Storm Kalmaegi was located at latitude 14.3°N and longitude 127.2°E which put it about 425 miles (685 km) east-southeast of Baler, Philippines.  Kalmaegi was moving toward northwest at 12 m.p.h. (19 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 Kalmaegi Forms East of Luzon

Tropical Storm Kalmaegi formed east of Luzon on Tuesday night.  At 10:00 p.m. EST on Tuesday the center of Tropical Storm Kalmaegi was located at latitude 12.9°N and longitude 128.8°E which put it about 350 miles (565 km) east of Legaspi, Philippines.  Kalmaegi was moving toward the west-northwest at 15 m.p.h. (24 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.

The Japan Meteorological Agency determined that former Tropical Depression 27W strengthened into Tropical Storm Kalmaegi on Tuesday night.  The circulation Kalmaegi was not well organized.  There was a large, broad area of low pressure, but there were few thunderstorms near the center of circulation.  Most of the stronger thunderstorms were occurring in bands in the northwestern part of Tropical Storm Kalmaegi.  Bands in the other portions of the circulation consisted primarily of showers and lower clouds.

Tropical Storm Kalmaegi will move through an environment marginally favorable for intensification.  Kalmaegi will move over water where the Sea Surface Temperature is near 29°C.  So, there is plenty of energy in the upper layer of the Western North Pacific Ocean to support intensification.  However, Tropical Storm Kalmaegi will move around the southwestern part of an upper level ridge centered south of Japan on Wednesday.  The ridge will produce northeasterly winds which will blow across the eastern part of the tropical storm.  Those winds will cause moderate vertical wind shear and they will inhibit intensification.  In 12 to 24 hours Kalmaegi will move closer to the western end of the ridge and the upper level winds will blow from the south.  The wind shear could decrease when the wind direction changes, which may allow the tropical storm to strengthen.

The ridge south of Japan will steer Tropical Storm Kalmaegi toward the northwest during the next 48 hours.  On its anticipated track Tropical Storm Kalmaegi could approach northeastern Luzon in 48 to 72 hours.  Since the strongest thunderstorms are in the northwestern part of Kalmaegi, the tropical storm could drop locally heavy rain over Luzon even if the center does not make landfall.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Fengshen continued to organize east of the Northern Marianas.  At 10:00 p.m. EST on Tuesday the center of Tropical Storm Fengshen was located at latitude 17.4°N and longitude 155.3°E which put it about 690 miles (1115 km) east-northeast of Saipan.  Fengshen was moving toward the west-northwest at 21 m.p.h. (34 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 1002 mb.

Tropical Storm Fengshen Forms East of Northern Marianas

Tropical Storm Fengshen formed east of the Northern Marianas on Tuesday.  At 4:00 p.m. EST on Tuesday the center of Tropical Storm Fengshen was located at latitude 17.1°N and longitude 157.1°E which put it about 805 miles (1300 km) east of Saipan.  Fengshen was moving toward the west-northwest at 18 m.p.h. (30 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 1000 mb.

More thunderstorms developed near the center of a cluster of thunderstorms east of the Northern Marianas on Tuesday and the Japan Meteorological Society designated the system as Tropical Storm Fengshen.  The distribution of thunderstorms around Tropical Storm Fengshen was asymmetrical.  Stronger thunderstorms were occurring in bands in the western half of the circulation.  Bands in the eastern half of the tropical storm consisted primarily of showers and lower clouds.  Fengshen was moving south of an upper level ridge over the Western North Pacific Ocean.  The ridge was producing easterly winds which were causing moderate vertical wind shear.  The wind shear was contributing to the asymmetrical distribution of thunderstorms.

Tropical Storm Fenshen will move through an environment favorable for intensification during the next several days.  Fengshen will move over water where the Sea Surface Temperature is near 29°C.  The upper level ridge will continue to cause vertical wind shear.  The wind shear will inhibit intensification, but the shear will not be strong enough to prevent intensification.  Tropical Storm Fengshen will intensify gradually and it could strengthen into a typhoon during the next two to three days.

Tropical Storm Fengshen will move around the western end of the ridge over the Western North Pacific.  The ridge will steer Fengshen toward the west-northwest during the next 24 to 36 hours.  Tropical Storm Fengshen will move more toward the north in about 36 hours when it reaches the western end of the ridge.  On its anticipated track Fengshen will pass northeast of the Northern Marianas.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 27W developed east of Luzon.  At 4:00 p.m. EST on Tuesday the center of Tropical Depression 27W was located at latitude 12.1°N and longitude 130.9°E which put it about 315 miles (510 km) east of Laoang, Philippines.  The depression 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 1004 mb.

Tropical Storm Nakri Brings Wind, Rain to Vietnam and Cambodia

Tropical Storm Nakri brought wind and rain to Vietnam and Cambodia on Sunday.  At 4:00 p.m. EST on Sunday the center of Tropical Storm Nakri was located at latitude 13.0°N and longitude 108.9°E which put it about 20 miles (35 km) west of Tuy Hoa, Vietnam.  Nakri was moving toward the west at 8 m.p.h. (13 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 992 mb.

The center of Tropical Storm Nakri made landfall on the coast of Vietnam near Tuy Hoa on Sunday.  The maximum sustained wind speed at the time of landfall was 65 m.p.h. (105 km/h).  Nakri moved slowly toward the west after it made landfall.  Tropical Storm Nakri has been weakening slowly since the center moved over land.  The heaviest rain was falling in bands in the western half of the circulation.  Heavy rain was falling over portions of southern Vietnam and northeastern Cambodia.  The strongest winds were occurring in the eastern half of Nakri which was still over the South China Sea.  Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Tropical Storm Nakri will move south of a ridge over high pressure over the South China Sea and southeast Asia.  The ridge will steer Nakri toward the west-northwest during the next 24 to 36 hours.  Tropical Storm Nakri will continue to weaken as it moves farther inland.  On its anticipated track Nakri will drop locally heavy rain over parts of southern Vietnam, northern Cambodia, southern Laos and eastern Thailand.  Heavy rain could cause flash floods in some locations.