Category Archives: Western North Pacific

Western Pacific Typhoons and Tropical Storms

Saudel Intensifies to a Typhoon

Former Tropical Storm Saudel intensified to a typhoon east of the Marianas on Friday morning.  At 11:00 a.m. EDT on Friday the center of Typhoon Saudel was located at latitude 16.4°N and longitude 147.8°E which put the center about 160 miles (260 km) east-northeast of Saipan.   Saudel was moving toward the north-northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 983 mb.

Typhoon Warnings are in effect for Pagan and Agrihan.

A Tropical Storm Warning is in effect for Alamagan.

A Typhoon Watch is also in effect for Alamagan.

Tropical Storm Watches are in effect for Tinian and Saipan.

Former Tropical Storm Saudel intensified to a typhoon on Friday morning.  The inner end of a rainband wrapped around the center of Typhoon Saudel.  A circular eye formed at the center of Saudel’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 Typhoon Saudel.  Storms near the center of Saudel generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the eastern half of Typhoon Saudel.  Winds to typhoon force extended out 35 miles (55 km) in the eastern half of Saudel’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Typhoon Saudel.

Typhoon Saudel will move through an environment that will be very favorable for intensification during the next 24 hours.  Saudel will move over water where the Sea Surface Temperatures are near 29°C.  It will move into a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Saudel will intensify during the next 24 hours.  Saudel is likely to intensify rapidly at times.  Typhoon Saudel is likely to strengthen to the equivalent of a major hurricane during the next 24 hours.

Typhoon Saudel will move around the southwestern part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Saudel toward the northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Saudel will be near Agrihan and Pagan in less than 12 hours.

Typhoon Saudel will bring strong winds and heavy rain to Pagan and Agrihan.  Heavy rain is likely to cause flash floods.  Saudel will also bring gusty winds and heavy rain to Alamagan. Typhoon Saudel could bring gusty winds to Tinian and Saipan.

Tropical Storm Saudel Strengthens

Tropical Storm Saudel strengthened on Thursday as it moved east of the Marianas.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Saudel was located at latitude 15.1°N and longitude 148.7°E which put the center about 215 miles (350 km) east of Saipan.  Saudel was moving toward the north-northwest 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 994 mb.

Typhoon Warnings are in effect for Pagan and Agrihan.

A Tropical Storm Warning is in effect for Alamagan.

A Typhoon Watch is also in effect for Alamagan.

Tropical Storm Watches are in effect for Tinian and Saipan.

Tropical Storm Saudel strengthened on Thursday.  Even though Saudel strengthened, the distribution of thunderstorms was still asymmetrical.  Thunderstorms were occurring mainly in bands in the southern half of Saudel’s circulation.  Bands in the northern side of Tropical Storm Saudel consisted primarily of showers and lower clouds.  Storms near the center of Saudel generated upper level divergence that pumped mass away to the south and west of the tropical storm.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds in Tropical Storm Saudel was also asymmetrical.  Winds to tropical storm force extended out 100 miles (160 km) in the southern side of Saudel’s circulation.  Winds to tropical storm force only extended out 45 miles (75 km) in the northern side of Tropical Storm Saudel.

Tropical Storm Saudel will move through an environment that will become more favorable for intensification during the next 24 hours.  Saudel will move over water where the Sea Surface Temperatures are near 29°C.  It will move into a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Saudel will intensify during the next 24 hours.  Saudel could intensify rapidly at times.  Tropical Storm Saudel is likely to strengthen to a typhoon on Friday.  Saudel could intensify to the equivalent of a major hurricane during the weekend.

Tropical Storm Saudel will move around the southwestern part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Saudel toward the northwest during the next 24 hours.  On its anticipated track, the center of Tropical Storm Saudel will be near Agrihan and Pagan in less than 24 hours.

Tropical Storm Saudel will bring strong winds and heavy rain to Pagan and Agrihan.  Heavy rain is likely to cause flash floods.  Saudel will also bring gusty winds and heavy rain to Alamagan.  Tropical Storm Saudel could bring gusty winds to Tinian and Saipan.

Tropical Storm Saudel Forms Northeast of Chuuk

Tropical Storm Saudel formed over the Western North Pacific Ocean northeast of Chuuk on Wednesday.  At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Saudel was located at latitude 8.9°N and longitude 153.9°E which put the center about 165 miles (265 km) northeast of Chuuk.  Saudel was moving toward the north at 5 m.p.h. (8 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.

A low pressure system over the Western North Pacific Ocean northeast of Chuuk strengthened on Tuesday night and the Japan Meteorological Agency designated the system as Tropical Storm Saudel.

The distribution of thunderstorms in Tropical Storm Saudel was asymmetrical.  Thunderstorms were occurring in bands in the western side of Saudel’s circulation.  Bands in the eastern side of Tropical Storm Saudel consisted primarily of showers and lower clouds.  Storms near the center of Saudel generated upper level divergence that pumped mass away to the west of the tropical storm.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds in Tropical Storm Saudel was also asymmetrical.  Winds to tropical storm force extended out 90 miles (145 km) in the southern side of Saudel’s circulation.  Winds to tropical storm force only extended out 45 miles in the northern side of Tropical Storm Saudel.

Tropical Storm Saudel will move through an environment favorable for intensification during the next 24 hours.  Saudel 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 is east of the Marianas.  The upper level ridge will produce northeasterly winds that will blow toward the top of Saudel’s circulation.  Those winds will cause moderate vertical wind shear.  The moderate vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Saudel will intensify during the next 24 hours.  Saudel is forecast to strengthen to a typhoon later this week.

Tropical Storm Saudel will move around the southwestern part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Saudel toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Saudel will pass north of Chuuk.  Saudel will be near the Northern Marianas in three days.

Tropical Storm Chan-hom Brings Wind and Rain to Honshu

Tropical Storm Chan-hom brought wind and rain to central Honshu on Tuesday morning.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Chan-hom was located at latitude 36.0°N and longitude 139.0°E which put the center about 25 miles (40 km) north of Tokyo, Japan.  Chan-hom was moving toward the west-southwest at 20 m.p.h. (32 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 994 mb.

The center of Tropical Storm Chan-hom crossed the coast of Honshu northeast of Tokyo on Tuesday morning.

The strongest winds were occurring in the northern side of Tropical Storm Chan-hom.  Winds to tropical storm force extended out 45 miles in the northern half of Chan-hom’s circulation.  The winds in the southern half of Tropical Storm Chan-hom were blowing at less than tropical storm force.

An upper level low south of Japan will steer Tropical Storm Chan-hom toward the west during the next 24 hours.  On its anticipated track, the center of Tropical Storm Chan-hom will move across central Honshu.

Tropical Storm Chan-hom will bring gusty winds and locally heavy rain to parts of central Honshu.  Heavy rain could cause floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Peilou continued to weaken slowly northwest of Wake Island.  At 11:00 a.m. EDT on Tuesday the center of Tropical Depression Peilou was located at latitude 26.7°N and longitude 160.1°E which put the center about 645 miles (1035 km) northwest of Wake Island.  Peilou was moving toward the east-northeast at 17 m.p.h. (28 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 999 mb.

Tropical Storm Chan-hom Moves Toward Japan

Tropical Storm Chan-hom was moving toward Japan on Monday morning.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Chan-hom was located at latitude 35.7°N and longitude 147.1°E which put the center about 460 miles (745 km) east of Tokyo, Japan.  Chan-hom was moving toward the northwest at 12 m.p.h. (19 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 981 mb.

The surface center of Tropical Storm Chan-hom is under the eastern part of an upper level low.  The upper level low is producing southeasterly winds that are blowing toward the top of Chan-hom’s circulation.  Those winds are causing moderate vertical wind shear.  The circulation around Tropical Storm Chan-hom is also puling drier air into the southern and eastern parts of Chan-hom’s circulation.

The combination of the moderate vertical wind shear and the drier air is causing the distribution of thunderstorms in Tropical Storm Chan-hom to be asymmetrical.  Thunderstorms are occurring in bands in the western half of Chan-hom’s circulation.  Bands in the eastern part of Tropical Storm Chan-hom consist primarily of showers and lower clouds.  Storm near the enter of Chan-hom generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds in Tropical Storm Chan-hom was also asymmetrical.  Winds to tropical storm force extended out 145 miles (235 km) in the northern half of Chan-hom’s circulation.  Winds to tropical storm force only extended out 70 miles (110 km) in the southern half of Tropical Storm Chan-hom.

Tropical Storm Chan-hom will move through an environment that will be somewhat favorable for intensification during the next 24 hours.  Chan-hom will move over water where the Sea Surface Temperatures are near 26°C.  However, the upper level low just to the west of the low level center of Chan-hom’s circulation will continue to cause moderate vertical wind shear.  Tropical Storm Chan-hom could intensify a little in spite of the moderate vertical wind shear.

The upper level low just to the west of the surface center of Tropical Storm Chan-hom will steer Chan-hom toward the west during the next 24 hours.  On its anticipated track, the center of Tropical Storm Chan-hom will reach the coast of Honshu northeast of Tokyo in about 24 hours.

Tropical Storm Chan-hom will bring strong winds and locally heavy rain to parts of central Honshu.  Heavy rain is likely to cause floods in some locations.

Elsewhere, Tropical Storm Dolphin continued to drop heavy rain over parts of eastern China and former Tropical Storm Peilou weakened to a tropical depression.

At 8:00 a.m. EDT on Monday the center of Tropical Storm Dolphin was located at latitude 29.0°N and longitude 117.9°E which put the center about 60 miles (95 km) southeast of Jingdezhen, China.  Dolphin was moving toward the north-northwest at 10 m.p.h. (16 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 990 mb.

At 11:00 a.m. EDT on Monday the center of Tropical Depression Peilou was located at latitude 22.1°N and longitude 153.6°E which put the center about 195 miles (315 km) south-southwest of Minami Tori Shima.  Peilou was moving toward the northeast at 20 m.p.h. (32 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 993 mb.

Typhoon Dolphin Hits Eastern China

Typhoon Dolphin hit the coast of eastern China near Wenzhou early on Sunday.  At 5:00 a.m. EDT on Sunday the center of Typhoon Dolphin was located at latitude 28.2°N and longitude 121.4°E which put the center about 50 miles (80 km) east of Wenzhou, China.  Dolphin was moving toward the west-northwest at 14 m.p.h. (22 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 954 mb.

Typhoon Dolphin made landfall on the east coast of China near Wenzhou early on Sunday.  Dolphin was a large typhoon.  Winds to typhoon force extended out 35 miles (55 km) from the enter of Dolphin’s circulation.  Winds to tropical storm force extended out 295 miles (475 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 12.7.  The Hurricane Size Index (HSI) is 16.7 and the Hurricane Wind Intensity Size Index (HWISI) is 29.4.  Typhoon Dolphin is similar in intensity to Hurricane Isaac when Isaac hit southeast Louisiana in 2012.  Typhoon Dolphin is much larger than Isaac was.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will continue to move farther inland over eastern China during the next 24 hours.

Typhoon Dolphin will bring strong winds and heavy rain to parts of eastern China.  Dolphin will bring strong winds and heavy rain to Zhejiang, Anhui, and Jiangsu.  Heavy rain is likely to cause floods in some locations.  Typhoon Dolphin could also produce a storm surge of up to 10 feet (3 meters) along parts of the east coast of China.

Even though Typhoon Dolphin will weaken as it moves farther inland, Dolphin could also drop heavy rain over parts of Henan, Shandong, Hebei, and Shanxi as it moves farther inland.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Chan-hom was still churning east of Japan and Tropical Storm Peilou formed south of Iwo To.

At 5:00 a.m. EDT on Sunday the center of Tropical Storm Chan-hom was located at latitude 32.4°N and longitude 150.5°E which put the center about 650 miles (1050 km) east-southeast of Tokyo, Japan.  Chan-hom was moving toward the west-northwest at 4 m.p.h. (6 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 984 mb.

At 5:00 a.m. EDT on Sunday the center of Tropical Storm Peilou was located at latitude 21.0°N and longitude 143.6°E which put the center about 265 miles (425 km) south-southeast of Iwo To.  Peilou was moving toward the east-southeast 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 998 mb.

Typhoon Dolphin Approaches East Coast of China

Typhoon Dolphin was approaching the east coast of China on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Typhoon Dolphin was located at latitude 27.9°N and longitude 122.7°E which put the center about 130 miles (210 km) east of Wenzhou, China.  Dolphin was moving toward the northwest at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 959 mb.

Typhoon Dolphin weakened gradually on Saturday as it approached the east coast of China.  Dolphin appeared to pull drier air from China into the western side of its circulation.  The drier air caused thunderstorms in bands in the western side of Typhoon Dolphin to weaken.  A small circular eye was still present at the center of Dolphin’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 still occurring in the eastern side of Dolphin’s circulation.  Storms near the core of Dolphin generated upper level divergence that pumped mass away from the typhoon.  The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased slowly on Saturday.

The area of stronger winds in Typhoon Dolphin decreased in size on Saturday.  Winds to typhoon force extended out 35 miles (55 km) from the enter of Dolphin’s circulation.  Winds to tropical storm force extended out 310 miles (500 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 11.5.  The Hurricane Size Index (HSI) is 17.0 and the Hurricane Wind Intensity Size Index (HWISI) is 28.5.  Typhoon Dolphin is similar in intensity to Hurricane Isaac when Isaac hit southeast Louisiana in 2012.  Typhoon Dolphin is much larger than Isaac was.

Typhoon Dolphin will move through an environment that will be unfavorable for intensification during the next 12 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is 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.  However, the circulation around Typhoon Dolphin will continue to pull drier air over China into its circulation.  Typhoon Dolphin is likely to continue to weaken gradually during the next 12 hours.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will hit the east coast of China just to the north of Wenzhou in less about 12 hours.

Typhoon Dolphin will bring strong winds and heavy rain to parts of eastern China.  Dolphin will bring strong winds and heavy rain to Zhejiang, Anhui, and Jiangsu.  Heavy rain is likely to cause floods in some locations.  Typhoon Dolphin could also produce a storm surge of up to 10 feet (3 meters) along parts of the east coast of China.

Typhoon Dolphin could also drop heavy rain over parts of Henan, Shandong, Hebei, and Shanxi after it moves inland.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Chan-hom continued to spin east of Japan.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Chan-hom was located at latitude 32.2°N and longitude 150.8°E which put the center about 670 miles (1080 km) east of Tokyo, Japan.  Chan-hom was moving toward the west-southwest 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 987 mb.

Typhoon Dolphin Moves Toward Eastern China

Typhoon Dolphin moved away from Okinawa and toward eastern China on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Dolphin was located at latitude 26.6°N and longitude 126.2°E which put the center about 350 miles (565 km) east-southeast of Wenzhou, China. Dolphin was moving toward the west at 11 m.p.h. (17 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 948 mb.

Typhoon Dolphin maintained its intensity as it moved away from Okinawa on Friday.  A small circular eye was visible at the center of Dolphin’s circulation.  A band of thunderstorms surrounded the eye and the strongest winds were occurring in that band of storms.  Bands of showers and thunderstorms were revolving around the core of Dolphin’s circulation.  Storms near the core of Dolphin generated upper level divergence that pumped mass away from the typhoon.  The removal of mass in the upper levels was nearly equal to the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure did not change much on Friday.

Typhoon Dolphin was a large typhoon.  Winds to typhoon force extended out 145 miles (235 km) in the northern half of Dolphin’s circulation.  Winds to typhoon force extended out 20 miles (30 km) in the southern half of Typhoon Dolphin.  Winds to tropical storm force extended out 305 miles (490 km) from the center of Dolphin’s circulation.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 17.8.  The Hurricane Size Index (HSI) is 32.3 and the Hurricane Wind Intensity Size Index (HWISI) is 50.1.  Typhoon Dolphin is similar in size and intensity to Hurricane Frances when Frances hit South Florida in 2004.

Typhoon Dolphin will move through an environment that will become less favorable for intensification during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge that is 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.  However, the circulation around Typhoon Dolphin could pull drier air over China into its circulation.  Typhoon Dolphin is likely to start to weaken gradually as it moved closer to eastern China.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin could hit the east coast of China in less than 48 hours.

The large circulation around Typhoon Dolphin will continue to produce strong winds and locally heavy rain to the Ryukyu Islands on Saturday.

Typhoon Dolphin will bring strong winds and heavy rain to parts of eastern China by the end of the weekend.  Dolphin will bring strong winds and heavy rain to Zhejiang, Anhui, and Jiangsu.  Heavy rain is likely to cause floods in some locations.  Typhoon Dolphin could also produce a storm surge of up to 10 feet (3 meters) along parts of the east coast of China.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Chan-hom weakened east of Japan.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Chan-hom was located at latitude 32.3°N and longitude 157.3°E which put the center about 1100 miles (1775 km) east of Tokyo, Japan.  Chan-hom 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 990 mb.

Typhoon Dolphin Hits Okinawa

Typhoon Dolphin hit Okinawa on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Typhoon Dolphin was located at latitude 27.2°N and longitude 128.3°E which put the center about 25 miles (40 km) north-northeast of Okinawa.  Dolphin was moving toward the west at 17 m.p.h. (28 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 955 mb.

Typhoon Dolphin started to intensify on Thursday evening as it approached Okinawa.  A small circular eye was visible at the center of Dolphin’s circulation on satellite and radar images.   Bands of showers and thunderstorms were revolving around the core of Dolphin’s circulation.    Storms near the core of Dolphin generated upper level divergence that pumped mass away from the typhoon.  The removal of mass in the upper levels was greater than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure decreased a little on Thursday.

The eye of Typhoon Dolphin was passing just to the north of Okinawa.  The southern part of the eyewall of Dolphin was passing over northern Okinawa.

A weather station at Naha Airport (ROAH) in Okinawa reported a sustained wind speed of 46 m.p.h. (74 km/h) and a wind gust of 61 m.p.h. (98 km/h).

Typhoon Dolphin was a large typhoon.  Winds to typhoon force extended out 140 miles (220 km) in the northern half of Dolphin’s circulation.  Winds to typhoon force extended out 70 miles (110 km) in the southern half of Typhoon Dolphin.  Winds to tropical storm force extended out 310 miles (500 km) from the center of Dolphin’s circulation.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 16.5.  The Hurricane Size Index (HSI) is 38.3 and the Hurricane Wind Intensity Size Index (HWISI) is 54.8

Typhoon Dolphin will move through an environment that will be favorable for intensification during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge that is 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 Dolphin could intensify on Friday as long as Okinawa does not disrupt the inner core of its circulation..

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will move west of the Ryukyu Islands on Friday.  Dolphin could hit the east coast of China in less than 48 hours.

Typhoon Dolphin will continue to bring strong winds and heavy rain to the Ryukyu Islands on Friday.  The strongest winds and heaviest rain will occur in Okinawa.  Heavy rain will cause flash floods in some locations.  Typhoon Dolphin could also cause a storm surge of up to 10 feet (3 meters) along the coast of some of the islands.

Even the center of Typhoon Dolphin will pass north of Taiwan, bands in the southern part of Dolphin’s circulation will drop heavy rain on northern Taiwan.

Typhoon Dolphin will also bring strong winds and heavy rain to eastern China.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Chan-hom formed southeast of Japan.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Chan-hom was located at latitude 29.6°N and longitude 160.3°E which put the center about 1300 miles (2095 km) east-southeast of Tokyo, Japan.  Chan-hom was moving toward the northwest 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 987 mb.

Typhoon Dolphin Continues Toward Okinawa

Typhoon Dolphin continued to move toward Okinawa on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Dolphin was located at latitude 26.3°N and longitude 132.9°E which put the center about 355 miles (570 km) east of Okinawa.  Dolphin was moving toward the west at 15 m.p.h. (24 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 956 mb.

Typhoon Dolphin weakened slowly on Wednesday.  The circulation around Dolphin pulled some drier air close to the core of the typhoon.  The drier air caused thunderstorms in some parts of Typhoon Dolphin to weaken.

There was still a small circular eye at the center of Typhoon Dolphin.  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 still were revolving around the core of Dolphin’s circulation.  There were wider areas of clear air in between the rainbands.  Storms near the core of Dolphin generated less upper level divergence that pumped less mass away from the typhoon. The removal of mass in the upper levels was less than the convergence of mass in the lower levels of the atmosphere.  So, the surface pressure increased on Wednesday.

The circulation around Typhoon Dolpin was still large on Wednesday.  Winds to typhoon force extended out 140 miles (220 km) from the center of Dolphin’s circulation.  Winds to tropical storm force extended out 305 miles (490 km) from the center of Typhoon Dolphin.

The Hurricane Intensity Index (HII) for Typhoon Dolphin is 13.9.  The Hurricane Size Index (HSI) is 44.7 and the Hurricane Wind Intensity Size Index (HWISI) is 58.6. Typhoon Dolphin is similar in intensity to Hurricane Sandy was when Sandy hit the East Coast of the U.S. in 2012.  Typhoon Dolphin is not quite as big as Sandy was.

Typhoon Dolphin will move through an environment that will be favorable for a strong typhoon during the next 24 hours.  Dolphin will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge that is 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.  However, the drier air being pulled into Dolphin’s circulation will inhibit intensification.  Typhoon Dolphin is likely to maintain its intensity on Thursday.

Typhoon Dolphin will move around the southern side of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Dolphin toward the west during the next 24 hours.  On its anticipated track, the center of Typhoon Dolphin will be near Minami Daito Jima in 12 hours. The center of Typhoon Dolpin will approach Okinawa in 24 hours,

Typhoon Dolphin will bring strong winds and heavy rain to Minami Daito Jima and to the central Ryukyu Islands including Okinawa later this week.  Heavy rains are likely to cause flash floods in some locations.  Typhoon Dolphin could also cause a storm surge of up to 10 feet (3 meters) along the coast of some of the islands.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Kujira dropped heavy rain on parts of Luzon.  Kujira weakened to a tropical depression after the center moved over Luzon.  At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Kujira was located at latitude 17.3°N and longitude 121.6°E which put the center about 25 miles (40 km) northwest of Cauayan, Philippines.  Kujira was moving toward the east-southeast at 7 m.p.h. (11 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 997 mb.