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Typhoon Hagibis Strengthens to Equivalent of Cat. 5 Hurricane over Northern Marianas

Typhoon Hagibis strengthened to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale over the Northern Marianas on Monday.  At 5:00 p.m. EDT on Monday the center of Typhoon was located at latitude 16.8°N and longitude 144.8°E which put it about 195 miles (305 km) north-northwest of Guam.  Hagibis was moving toward the west-northwest at 20 m.p.h. (32 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 195 m.p.h. (305 km/h).  The minimum surface pressure was 915 mb.

Typhoon Hagibis rapidly intensified into the equivalent of a Category 5 hurricane on Monday.  A small, pinhole eye was surrounded by a ring of strong thunderstorms.  The strongest winds were occurring in that ring of storms.  A rainband appeared to be wrapping around the original eye and eyewall and an eyewall replacement cycle could be underway.  The start of an eyewall replacement cycle may have ended the period of rapid intensification.  Bands of showers and thunderstorms were revolving around the core of Typhoon Hagibis.  Storms around the core were generating strong upper level divergence which was pumping mass away from the typhoon.

The apparent beginning of an eyewall replacement cycle produced an increase in the size of the circulation around Typhoon Hagibis.  Winds to typhoon force extended out 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 250 miles (400 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Hagibis was 35.0.  The Hurricane Size Index (HSI) was 27.8 and the Hurricane Wind intensity Size Index (HWISI) was 62.8.  Hagibis was capable of causing catastrophic damage.

The center of Typhoon Hagibis passed north of Tinian and Saipan.  Hagibis would have produced very strong winds on some of the Northern Marianas.  The strongest winds would have occurred between Saipan and Alamagan.  Typhoon Hagibis also dropped heavy rain over Saipan, Tinian, Rota and Guam.

Typhoon Hagibis will remain in an environment very favorable for strong typhoons during the next 24 to 36 hours.  Hagibis will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Hagibis is likely to weaken, while the inner eyewall dissipates and the outer eyewall becomes the part of the typhoon with the strongest winds.  Hagibis could strengthen again if the outer eyewall begins to contract.  An eyewall replacement cycle would increase the size of the circulation.

Typhoon Hagibis will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean.  The ridge will steer Hagibis toward the northwest during the next several days.  Typhoon Hagibis will move toward the northeast after it moves around the western of the high pressure system.  On its anticipated track Typhoon Hagibis could approach the coast of Honshu near Tokyo by the end of this week.

Typhoon Hagibis Rapidly Intensifies Into Equivalent of Major Hurricane

Typhoon Hagibis rapidly intensified into the equivalent of a major hurricane east of the Marianas on Sunday night.  At 11:00 p.m. EDT on Sunday the cener of Typhoon Hagibis was located at latitude 15.3°N and longitude 148.8°E which put it about 320 miles (515 km) east-northeast of Guam.  Hagibis was moving toward the west-northwest at 19 m.p.h. (31 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 953 mb.

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

Typhoon Hagibis intensified very rapidly on Sunday night.  The maximum sustained wind speed increased from 75 m.p.h. (120 km/h) to 115 m.p.h. (185 km/h) in six hours.  A small circular eye formed at the center of Hagibis and a ring of strong thunderstorms surrounded the eye.  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 strong upper level divergence which was pumping mass away in all directions.  The removal of mass was allowing the minimum surface pressure to decrease rapidly.

The circulation around Typhoon Hagibis was increasing in size.  Winds to typhoon force extended out 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Hagibis was 20.2.  The Hurricane Size Index (HSI) was 18.1 and the Hurricane Wind intensity Size Index (HWISI) was 38,3,  Typhoon Hagibis was capable of causing major damage.

Typhoon Hagibis will continue to move through an environment very favorable for intensification for another 24 to 36 hours.  Hagibis will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Hagibis could continue to intensify rapidly and it could strengthen into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale during the next 24 hours.  At some point a rainband is likely to wrap around the existing eye and eyewall and an eyewall replacement cycle will end the intensification of Typhoon Hagibis.

Typhoon Hagibis will move around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer Hagibis toward the west-northwest during the next 12 to 24 hours.  Hagibis will turn more toward the northwest in a day or so.  On its anticipated track Typhoon Hagibis will reach the Marianas in about 12 hours.  The center of Hagibis is likely to pass north of Saipan.  Typhoon Hagibis will bring strong winds and heavy rain.  It will be capable of causing major damage to the Northern Marianas.  Typhoon Hagibis could approach southwestern Japan in four or five days.

Hagibis Strengthens to a Typhoon, Warnings Issued for Marianas

Former Tropical Storm Hagibis strengthened into a typhoon Sunday and warnings were issued for the Marianas.  At 5:00 p.m. EDT on Sunday the center of Typhoon Hagibis was located at latitude 15.1°N and longitude 150.3°E which put it about 425 miles (685 km) east-northeast of Guam.  Hagibis was moving toward the west-northwest at 16 m.p.h. (26 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 978 mb.

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

Typhoon Hagibis exhibited much better organization on satellite images on Sunday.  The inner end of a rainband wrapped almost entirely around the center of circulation and an eye was forming in the middle of Hagibis.  Other bands of showers and thunderstorms were revolving around the core of Typhoon Hagibis.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.  Winds to typhoon force extend out 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out 145 miles (230 km) from the center.

Typhoon Hagibis will move through an environment very favorable for intensification during the next 48 to 72 hours.  Hagibis will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Hagibis will continue to intensify and it is likely to intensify rapidly once the eye and eyewall are fully developed.  Hagibis could strengthen into the equivalent of a major hurricane within 36 hours and it could intensify to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale within 72 hours.

Typhoon Hagibis will move around the southwestern portion of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Hagibis toward the west-northwest during the next 24 to 48 hours.  Typhoon Hagibis will move more toward the northwest when it gets closer to western end of the ridge in a couple of days.  On its anticipated track Typhoon Hagibis will move through the Marianas in about 24 hours.  The center of Hagibis is forecast to pass north of Saipan.  Typhoon Hagibis will bring strong gusty winds and heavy rain to portions of the Northern Marianas.

Dangerous Typhoon Yutu Slams Tinian and Saipan

Dangerous Typhoon Yutu slammed Tinian and Saipan on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Yutu was located at latitude 15.5°N and longitude 144.8°E which put it about 35 miles (55 km) west-northwest of Saipan.  Yutu was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 205 m.p.h. (330 km/h).  The minimum surface pressure was 908 mb.

Typhoon Warnings were in effect for Rota, Tinian and Saipan.  Tropical Storm Warnings were in effect for Guam, Alamagan, Pagan and Agrihan.

The eye of Typhoon Yutu passed directly over Tinian on Wednesday and the northern side of the eyewall moved over Saipan.  So, they would have experienced the strongest parts of Typhoon Yutu.  The Hurricane Intensity Index (HII) for Typhoon Yutu is 40.4.  The Hurricane Size Index (HSI) is 26.7 and the Hurricane Wind Intensity Size Index (HWISI) is 67.1.  Typhoon Yutu was capable of causing widespread catastrophic damage when it passed over Tinian and Saipan.

Yutu is still a very powerful typhoon, but an eyewall replacement cycle appears to have started.  A rainband has wrapped around the original eye and eyewall.  The inner eye and eyewall are still intact and the strongest winds are occurring in the ring of thunderstorms that surround the original eye.  The imminent formation of a second, outer eyewall increased the size of the circulation around Typhoon Yutu.  Winds to typhoon force extend out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extend out about 240 miles (390 km) from the center.

Typhoon Yutu will remain in an environment capable of supporting a very strong typhoon for several more days.  Yutu will move over water where the Sea Surface Temperature is near 31°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  The incipient eyewall replacement cycle will cause Typhoon Yutu to weaken when the inner eyewall dissipates.  However, Yutu could strengthen again, if it remains in a favorable environment and the outer eyewall contracts closer to the center of circulation.  Typhoon Yutu is likely to remain a powerful typhoon during the next 48 hours.

Typhoon Yutu will move southwest of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Yutu toward the west-northwest during the next several days.  On its anticipated track Typhoon Yutu will move away from the Northern Marianas, and conditions should gradually improve there.  Yutu could be south of Okinawa in four or five days.

Typhoon Yutu Intensifies Rapidly to Equivalent of Cat. 4 Hurricane, Imminent Threat to Marianas

Typhoon Yutu intensified rapidly on Tuesday into the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale and Yutu posed an imminent threat to the Marianas.  At 11:00 p.m. EDT on Tuesday the center of Typhoon Yutu was located at latitude 13.6°N and longitude 147.5°E which put it about 155 miles (255 km) east-southeast of Rota.  Yutu was moving toward the northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 935 mb.

Typhoon Warnings are in effect for Rota, Saipan and Tinian.  Tropical Storm Warnings are in effect for Guam, Alamagan, Pagan and Agrihan.

Typhoon Yutu intensified rapidly during the past 24 hours.  A circular eye developed at the center of Yutu.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Numerous bands of showers and thunderstorms were revolving around the core of Typhoon Yutu.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.  The removal of mass allowed the surface pressure to decrease rapidly.

Typhoon Yutu has a large circulation.  Winds to typhoon force extend out about 65 miles (105 km) from the center of circulation.  Winds to tropical storm force extend out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Yutu is 31.6.  The Hurricane Size Index (HSI) is 20.8 and the Hurricane Wind Intensity Size index (HWISI) is 52.4.  Typhoon Yutu is capable of causing widespread extensive damage.

Typhoon Yutu will move through an environment favorable for further intensification during the next several days.  Yutu will move over water where the Sea Surface Temperature is near 31°C.  It will move through a region where the upper level winds are weak and there is little vertical wind shear.  Typhoon Yutu could intensify into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  At some point a rainband will wrap around the existing eye and eyewall, and an eyewall replacement cycle will occur.  Yutu will weaken during the eyewall replacement cycle, but the typhoon could strengthen afterwards if it remains in an environment favorable for intensification.

Typhoon Yutu will move around the southwestern portion of a ridge of high pressure over the Western North Pacific Ocean.  The ridge will steer Yutu in a general west-northwesterly direction.  On its anticipated track Typhoon Yutu will reach the Northern Marianas in about 12 hours.  The core of Yutu will pass between Rota and Tinian.  Rota, Tinian and Saipan are likly to have winds to typhoon force.  Typhoon Yutu will be capable of causing extensive damage in those locations.  Guam, Alamagan, Pagan and Agrihan are likely to receive winds to tropical storm force.  Wind speeds will be stronger on the northern part of Guam and the damage potential is greater there than it is for the southern part of Guam.

Typhoon Jebi Hits Northern Marianas

Typhoon Jebi hit the Northern Mariana Islands on Thursday.  At 11:00 a.m. EDT on Thursday the center of Typhoon Jebi was located at latitude 17.8°N and longitude 146.2°E which put it about 35 miles (55 km) east-southeast of Pagan.  Jebi was moving toward the west at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 155 m.p.h. (230 km/h).  The minimum surface pressure was 940 mb.  A Typhoon Warning was in effect for Agrihan, Pagan and Alamagan.

Typhoon Jebi was very well organized.  There was a small eye at the center of circulation.  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 Jebi.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon.

Winds to typhoon force extended out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 185 miles (295 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Jebi was 23.6.  The Hurricane Size Index (HSI) was 19.4 and the Hurricane Wind Intensity Size Index (HWISI) was 43.0.  Those indices indicate that Typhoon Jebi was capable of causing major damage.

Typhoon Jebi will be moving through an environment favorable for intensification during the next day or so.  Jebi 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 is little vertical wind shear.  Typhoon Jebi is forecast to intensify during the next 24 hours.  If an outer rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause the typhoon to weaken at least temporarily.

Typhoon Jebi will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  Jebi will make a gradual turn toward the north during the next few days while it moves around the end of the ridge.  On its anticipated track Typhoon Jebi will move slowly away from the Northern Marianas.  Weather conditions should slowly improve when Jebi moves away.  The center of Jebi is forecast to pass south of Iwo To.  Typhoon Jebi could approach Honshu in four or five days.

Typhoon Jebi Intensifies Rapidly East of Northern Marianas

Typhoon Jebi intensified rapidly east of the Northern Marianas on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Jebi was located at latitude 17.5°N and longitude 149.8°E which put it about 270 miles (435 km) east of Pagan.  Jebi was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (205 km/h).  The minimum surface pressure was 959 mb.  A Typhoon Warning was in effect for Agrihan, Pagan and Alamagan in the Northern Marianas.

The circulation of Typhoon Jebi was very well organized and it was symmetrical.  A small circular eye formed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of thunderstorms were revolving around the core of Typhoon Jebi.  Storms around the core were generating strong upper level divergence which was pumping large quantities of mass away from the typhoon.  Winds to typhoon force extended out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center.

Typhoon Jebi will be moving through an environment very favorable for further intensification.  Jebi 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.  Jebi is likely to intensify into the equivalent of a major hurricane on Thursday.

Typhoon Jebi will move south of a subtropical ridge over the Western North Pacific for several more days.  The ridge will steer Jebi in a general westerly direction during that time.  Typhoon Jebi will reach the western end of the ridge in about 48 hours.  Jebi will make a gradual turn toward the north when it reaches the end of the ridge.  On its anticipated track Typhoon Jebi will reach the northernmost Mariana Islands within 24 hours.  Jebi will be capable of causing major damage when it arrives.  Jebi is forecast to pass south of Iwo To, but it will turn toward the major islands of Japan during the weekend.