Tag Archives: Tropical Storm Usagi

Typhoon Man-Yi Strengthens to Equivalent of a Major Hurricane

Typhoon Man-yi strengthened to the equivalent of a major hurricane as it moved toward the Philippines on Friday.  At 4:00 p.m. EST on Friday the center of Typhoon Man-yi was located at latitude 12.3°N and longitude 127.2°E which put the center about 490 miles (790 km) east-southeast of Manila, Philippines.  Man-yi was moving toward the west-northwest at 15 m.p.h. (24 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 952 mb.

Typhoon Man-yi intensified to the equivalent of a major hurricane on Friday.  A circular eye with a diameter of 25 miles (40 km) was at the center of Man-yi’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Man-yi’s circulation.  Storms near the center of Man-yi generated strong upper level divergence that pumped mass away from the typhoon in all directions.  The removal of large quantities of mass caused the surface pressure to decrease rapidly.

The circulation around Typhoon Man-yi was very symmetrical.  Winds to typhoon force extended out 30 miles (50 km) from the center of Man-yi’s circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center of Typhoon Man-yi.

The Hurricane Intensity Index (HII) for Typhoon Man-yi was 23.6.  The Hurricane Size Index (HSI) was 10.3 and the Hurricane Wind Intensity Size Index (HWISI) was 33.9.  Typhoon Man-yi was similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

Typhoon Man-yi will move through an environment favorable for intensification during the next 24 hours.  Man-yi will move over water where where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Man-yi is likely to continue to intensify during the next 24 hours.

Typhoon Man-yi will move around the southern side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Man-yi toward the west-northwest during the next 24 hours.  On its anticipated track, Typhoon Man-yi will reach southeastern Luzon in less than 18 hours.

Typhoon Man-yi will bring very strong winds and heavy rain to Luzon.  Heavy rain will cause flash floods and mudslides.  Man-yi could also cause a storm surge of up to 13 feet (4 meters) along the coast of Luzon.  Luzon has already been hit by a series of in recent weeks.  Typhoon Man-yi is capable of causing regional major damage.  Man-yi will seriously set back efforts to recover from the previous typhoons.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Usagi was bringing wind and rain to Taiwan.  At 4:00 p.m. EST on Friday the center of Tropical Storm Usagi was located at latitude 22.5°N and longitude 120.3°E which put the center about 25 miles (40 km) southwest of Kaohsiung, Taiwan.  Usagi was moving toward the north-northeast at 10 m.p.h. (16 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 998 mb.  Heavy rain is likely to cause flash floods in Taiwan.

Tropical Storm Man-yi Brings Gusty Winds to Guam

Tropical Storm Man-yi brought gusty winds to Guam on Tuesday.  At 4:00 p.m. EST on Tuesday the center of Tropical Storm Man-yi was located at latitude 12.5°N and longitude 144.4°E which put the center about 40 miles (65 km) southeast of Guam.  Man-yi was moving toward the southwest at 18 m.p.h. (30 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 Warnings were in effect for Guam, Rota, Tinian, and Saipan.

Tropical Storm Man-yi brought gusty wind to Guam and the Marianas on Tuesday.  A weather station at the Guam International Airport reported a sustained wind speed of 30 m.p.h. (50 km/h) and a wind gust of 48 m.p.h. (77 km/h) on Tuesday.

The circulation around Tropical Storm Man-yi was somewhat disorganized.  There were not many thunderstorms near the center of Man-yi’s circulation.  Thunderstorms were occurring in bands in the southern side of the center of Tropical Storm Man-yi.  Bands in the northern side of Man-yi’s circulation consisted primarily of showers and lower clouds.

The circulation around Tropical Storm Man-yi was small.  Winds to tropical storm force extended out 85 miles (135 km) from the center of Man-yi’s circulation.

Tropical Storm Man-yi will move through an environment somewhat favorable for intensification during the next 24 hours.  Man-yi will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the southern side of an upper level ridge over the Western North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Man-yi’s circulation.  Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but the shear may not be enough to prevent intensification. Tropical Storm Man-yi could intensify during the next 24 hours.

Tropical Storm Man-yi will move around the southern side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Man-yi toward the west during the next 24 hours.  On its anticipated track, Tropical Storm Man-yi will move away from the Marianas.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Usagi strengthened east of the Philippines, Tropical Depression Yinxing moved inland over Vietnam, and Tropical Storm Toraji was spinning over the South China Sea southeast of Hong Kong.

At 4:00 p.m. EST on Tuesday the center of Tropical Storm Usagi was located at latitude 15.0°N and longitude 128.3°E which put the center about 530 miles (850 km) east of Manila, Philippines.  Usagi was moving toward the west at 17 m.p.h. (28 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 987 mb.

At 10:00 a.m. EST on Tuesday the center of Tropical Depression Yinxing was located at latitude 14.0°N and longitude 108.2°E which put the center about 145 miles (235 km) south of Da Nang, Vietnam.  Yinxing was moving toward the west at 9 m.p.h. (15 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 1004 mb.

At 4:00 p.m. EST on Tuesday the center of Tropical Storm Toraji was located at latitude 20.1°N and longitude 116.8°E which put the center about 245 miles (395 km) southeast of Hong Kong.  Toraji 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 997 mb.

Tropical Storm Usagi Forms East of the Philippines

Tropical Storm Usagi formed over the Western North Pacific Ocean east of the Philippines on Monday.  At 4:00 p.m. EST on Monday the center of Tropical Storm Usagi was located at latitude 13.0°N and longitude 134.2°E which put the center about 945 miles (1525 km) east of Manila, Philippines.  Usagi was moving toward the west at 17 m.p.h. (28 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 991 mb.

Another tropical storm formed east of the Philippines on Monday.  Former Tropical Depression Twentyseven-W strengthened and the Japan Meteorological Agency designated the system as Tropical Storm Usagi.  More thunderstorms formed near the center of Usagi’s circulation.  However, the distribution of thunderstorms in Tropical Storm Usagi was asymmetrical.  Many of the thunderstorms were occurring in bands in the western half of Usagi’s circulation.  Bands in the eastern half of Tropical Storm Usagi consisted primarily of showers and lower clouds.  Storms near the center of Usagi generated upper level divergence that pumped mass away to the west of the tropical storm.

The circulation around Tropical Storm Usagi was small.  Winds to tropical storm force extended out 50 miles (80 km) from the center of Usagi’s circulation.

Tropical Storm Usagi will move through an environment favorable for intensification during the next 24 hours.  Usagi will move over water where the Sea Surface Temperatures are near 30°C.   It will move under the southern side of an upper level ridge over the Western North Pacific Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Usagi’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 intensification.  Tropical Storm Usagi will intensify during the next 24 hours.  Usagi could strengthen to a typhoon on Tuesday.

Tropical Storm Usagi will move around the southern side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Usagi toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Usagi will move toward the Philippines.

Elsewhere over the Western North Pacific Ocean, former Typhoon Toraji weakened as it moved away from the Philippines, Tropical Storm Yinxing approached the coast of Vietnam, Tropical Storm Watches were issued in the Marianas for Tropical Storm Man-yi.

At 4:00 p.m. EST on Monday the center of Tropical Storm Toraji was located at latitude 18.5°N and longitude 118.7°E which put the center about 420 miles (675 km) southeast of Hong Kong.  Toraji was moving toward the west-northwest at 10 m.p.h. (16 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 985 mb.

At 4:00 p.m. EST on Monday the center of Tropical Storm Yinxing was located at latitude 14.6°N and longitude 109.6°E which put the center about 130 miles (210 km) southeast of Da Nang, Vietnam.  Yinxing was moving toward the south-southwest at 10 m.p.h. (16 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 999 mb.

At 4:00 p.m. EST on Monday the center of Tropical Storm Man-yi was located at latitude 14.0°N and longitude 150.5°E which put the center about 430 miles (695 km) east of Guam.  Man-yi was moving toward the west-southwest at 8 m.p.h. (13 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 992 mb.

Tropical Storm Watches were in effect for Guam, Rota, Tinian and Saipan.

Tropical Storm Usagi Forms East of Vietnam

Tropical Storm Usagi formed over the South China Sea east of Vietnam on Thursday.  At 10:00 a.m. EST on Thursday the center of Tropical Storm Usagi was located at latitude 11.2°N and longitude 113.7°E which put it about 350 miles (565 km) east of Lien Huong, Vietnam.  Usagi was moving toward the west at 18 m.p.h. (29 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.

More thunderstorms developed near the center of former Tropical Depression 33W and the Japan Meteorological Agency designated the system as Tropical Storm Usagi.  Satellite imagery indicated that the inner end of a rainband was wrapping around the center of circulation.  Several other bands of showers and thunderstorms were in the western half of Tropical Storm Usagi.  Bands in the eastern half of the circulation consisted primarily of showers and low clouds.  An upper level ridge north Usagi was producing southeasterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear and they were the reason why the stronger thunderstorms were developing west of the center of circulation.  Storms near the center were producing upper level divergence which was pumping mass away to the west of the tropical storm.

Tropical Storm Usagi will move through an environment favorable for intensification during the next 24 to 36 hours.  Usagi will move over water where the Sea Surface Temperature is near 29°C.  It will continue to move south of an upper level ridge and moderate vertical wind shear will continue to affect Tropical Storm Usagi.  The wind shear will slow intensification, but Usagi will strengthen during the next day or so.  It could intensify into a typhoon during the next 36 hours.

The ridge north of Tropical Storm Usagi will steer the tropical storm on a track a little to the south of due west.  On its anticipated track the center of Tropical Storm Usagi will approach the coast of southern Vietnam in about 36 hours.  Usagi could make landfall on the portion of the coast between Cam Ranh and Vung Tau.  Tropical Storm Usagi will bring gusty winds and it could drop locally heavy rain over southern Vietnam and Cambodia.  Heavy rain could cause flash foods in some locations.

Elsewhere over the Western North Pacific, Typhoon Man-yi was moving away from the Marianas after causing power outages in southern Guam.  At 10:00 a.m. EST on Thursday the center of Typhoon Man-yi was located at latitude 13.5°N and longitude 137.8°E which put it about 1155 miles (1860 km) southeast of Okinawa.  Man-yi was moving toward the northwest at 21 m.p.h. (34 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 969 mb.