Tag Archives: Tropical Storm Neoguri

Typhoon Bualoi Strengthens to Equivalent of Major Hurricane over Marianas

Typhoon Bualoi strengthened to the equivalent of a major hurricane over the Marianas on Monday.  At 5:00 p.m. EDT on Monday the center of Typhoon Bualoi was located at latitude 16.7°N and longitude 145.5°E which put it about 660 miles (1060 km) south-southeast of Iwo To.  Bualoi was moving toward the northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 949 mb.

Typhoon Bualoi continued to intensify quickly on Monday.  There was a small eye at the center of Bualoi.  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 Bualoi.  Storms near the core were generating upper level divergence which was pumping mass away from the typhoon in all directions.

The circulation around Typhoon Bualoi was small.  Winds to typhoon force extended out 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out 115 miles (185 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Bualoi was 25.1.  The Hurricane Size Index (HSI) was 10.0 and the Hurricane Wind intensity Size Index (HWISI) was 35.1.  Typhoon Bualoi was capable of causing localized major damage.  The core of Bualoi where the strongest winds were occurring passed north of Saipan.

Typhoon Bualoi will move through an environment capable of supporting a strong typhoon for another 24 to 36 hours.  Bualoi 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.  Bualoi could strengthen during the next 24 hours.  If an inner rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause the typhoon to start to weaken.

Typhoon Bualoi will move around the western end of high pressure system over the Western North Pacific Ocean.  The high will steer Bualoi toward the northwest during the next 24 hours.  The typhoon will move more toward the north when it reaches the western end of the high pressure system.  On its anticipated track Typhoon Bualoi will move away from the Northern Marianas.  Conditions should improve when Bualoi gets farther away.  Typhoon Bualoi could be near Iwo To in about 60 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Neoguri was moving south of Honshu.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Neoguri was located at latitude 32.4°N and longitude 137.6°E which put it about 285 miles (460 km) southwest of Tokyo, Japan.  Neoguri was moving toward the east-northeast at 14 m.p.h. (22 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 997 mb.  The center of Tropical Storm Neoguri is likely to pass south of Tokyo during in about 12 hours.

Typhoon Bualoi Strengthens as it Approaches the Marianas

Typhoon Bualoi strengthened as it approached the Marianas on Sunday.  At 11:00 p.m. EDT on Sunday the center of Typhoon Bualoi was located at latitude 14.5°N and longitude 147.8°E which put it about 175 miles (285 km) east-southeast of Saipan.  Bualoi was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 967 mb.

Typhoon Warnings were in effect for Tinian and Saipan.  A Typhoon Watch was in effect for Rota.  Tropical Storm Watches were in effect for Alamagan, Pagan and Agrihan.

Typhoon Bualoi strengthened quickly on Sunday.  A small circular eye developed at the center of Bualoi.  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 the typhoon.  Storms near the core were generating upper level divergence which was pumping mass away from Bualoi in all directions.

The circulation around Typhoon Bualoi was relatively small.  Winds to typhoon force extended out 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out 130 miles (215 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Bualoi was 16.5.  The Hurricane Size Index (HSI) was 9.8 and the Hurricane Wind Intensity Size Index (HWISI) was 26.3.  Bualoi was capable of causing localized serious damage.

Typhoon Bualoi will move through an environment favorable for intensification for another 36 to 48 hours.  Bualoi 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 Bualoi will continue to intensify and it could strengthen into the equivalent of a major hurricane during the next 12 to 24 hours.

Typhoon Bualoi will move around the western end of a high pressure system over the Western North Pacific.  The high will steer Bualoi toward the northwest during the next 48 hours.  The typhoon will move more toward the north when it reaches the western end of the high pressure system.  On its anticipated track the center of Typhoon Bualoi could pass near Saipan in about 12 hours.  If the center passes near or over Saipan, then there will be winds of typhoon force.  However, since the circulation around Bualoi is fairly small, if the typhoon passes north of Saipan, it will receive much weaker winds.  Typhoon Bualoi could be near Iwo To in less than three days.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Neoguri was moving toward Honshu.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Neoguri was located at latitude 29.5°N and longitude 133.6°E which put it about 600 miles (965 km) southwest of Tokyo, Japan.  Neoguri was moving toward the north-northeast 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 989 mb.  Tropical Storm Neoguri could pass close to the coast of Honshu near Tokyo in about 24 hours.

Tropical Depression 22W Forms East of Guam

Tropical Depression 22W formed east of Guam on Friday night.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 22W was located at latitude 10.5°N and longitude 156.0°E which put it about 815 miles (1315 km) east of Guam.  The depression was moving toward the west-northwest at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1006 mb.

The circulation around Tropical Depression 22W was still organizing on Friday night.  More thunderstorms were forming near the center of circulation.  Bands of showers and thunderstorms were developing and were beginning to revolve around the center of circulation.  Storms near the center started to generate upper level divergence which was pumping mass away from the tropical depression.

Tropical Depression 22W will move through an environment favorable for intensification during the next several days.  The depression 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 not be a lot of vertical wind shear.  Tropical Depression 22W is likely to intensify into a tropical storm during the weekend and it could strengthen into a typhoon by early next week.

Tropical Depression 22W will move south of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer the depression toward the west-northwest during the next two to three days.  On its anticipated track the depression could reach the Marianas within 72 hours.  It could be a typhoon by that time.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Neoguri strengthened south of Okinawa.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Neoguri was located at latitude 21.3°N and longitude 127.8°E which put it about 370 miles (600 km) south of Okinawa.  Neoguri was moving toward the northwest at 7 m.p.h. (11 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 985 mb.  Tropical Storm Neoguri could approach the southern Ryukyu Islands including Okinawa in about 36 hours.

Tropical Storm Neoguri Forms East of Northern Luzon

Tropical Storm Neoguri formed east of northern Luzon on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Neoguri was located at latitude 20.1°N and longitude 129.4°E which put it about 470 miles (755 km) south-southeast of Okinawa and about 500 miles (800 km) east-northeast of the northern end of Luzon.  Neoguri was moving toward the north-northwest at 7 m.p.h. (11 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.

A distinct low level center of circulation developed on the western side of a cluster of thunderstorms east of northern Luzon on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Neoguri.  The circulation around Neoguri exhibited much more organization.  The inner part of a rainband wrapped around the center of circulation.  A broken ring of thunderstorms formed around the southwestern half of the center and an elliptical eyelike feature appeared on microwave satellite images.  The long axis of the elliptical eye was oriented northeast to southwest.  Bands of showers and thunderstorms developed in the eastern half of Tropical Storm Neoguri.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Thunderstorms near the center generated upper level divergence which pumped mass away to the northeast of the tropical storm.

Tropical Storm Neoguri will move through an environment mostly favorable for intensification during the next 24 to 36 hours.  Neoguri will move over water where the Sea Surface Temperature is near 28°C.  It will move under the western part of an upper level ridge where the winds are weaker.  There will not be a lot of vertical wind shear during the next 24 hours.  There appears to be drier air to the northwest of Tropical Storm Neoguri, which may be the reason why the rainbands in the western half of the circulation are weaker.  If Neoguri pulls drier air into the core of the circulation, then that would inhibit intensification.  On the other hand, if an eye does form completely, then Tropical Storm Neoguri could strengthen into a typhoon.

The future track of Tropical Storm Neoguri will depend on how strong it becomes.  If Neoguri strengthens, then a trough over China will likely steer the tropical storm toward the northeast.  However, if drier air gets pulled into the core of the circulation, then a weaker Tropical Storm Neoguri would be steered by winds closer to the surface.  A high pressure system over the Western North Pacific would steer Tropical Storm Neoguri toward the west.  Guidance from numerical models is split between these two scenarios.  Some models forecast a track toward the northeast and other models predict a track toward the west.  Tropical Storm Neoguri did not move much on Thursday and either scenario is possible.