Tag Archives: Northern Marianas

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.

Tropical Storm Jebi Forms East of the Marianas

Tropical Storm Jebi formed east of the Marianas on Monday.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Jebi was located at latitude 15.8°N and longitude 156.6°E which put it about 745 miles (1200 km) east of Saipan.  Jebi was moving toward the northwest at 17 m.p.h. (28 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 1004 mb.

A distinct low level center of circulation developed in a cluster of showers and thunderstorms east of the Northern Marianas and the Japan Meteorological Agency designated the system as Tropical Storm Jebi.  The circulation of Jebi was still organizing.  A primary rainband wrapped around the eastern and northern sides of the center of circulation.  Other bands of showers and thunderstorms were developing in the eastern half of the circulation.  Storms near the center started to generate upper level divergence.

Tropical Storm Jebi will move through an environment favorable for intensification during the next several days.  Jebi 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 cause some vertical wind shear.  Two upper level lows northwest and northeast of Jebi will enhance upper level divergence to the north of the tropical storm.  Tropical Storm Jebi will strengthen and it could become a typhoon later this week.

Tropical Storm Jebi will move southwest of a ridge over the Western North Pacific Ocean.  The ridge is forecast to strengthen and it will steer Jebi in a general west-northwesterly direction during the next several days.  On its anticipated track Tropical Storm Jebi could be near the northernmost Mariana Islands in about three days.  Jebi could be a typhoon by that time.  Jebi could be south of Iwo To by the end of the week.

Large Typhoon Soulik Nears Ryukyu Islands, Cimaron Brushes Northern Marianas

Large Typhoon Soulik neared the Ryukyu Islands on Monday night, while Typhoon Cimaron brushed the Northern Mariana Islands.  At 11:00 p.m. EDT on Monday the center of Typhoon Soulik was located at latitude 28.0°N and longitude 131.7°E which put it about 160 miles (260 km) south-southeast of Yaku Shima, Japan.  Soulik was moving toward the northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (215 km/h).  The minimum surface pressure was 952 mb.

A large circular eye with a diameter of 50 miles (80 km) developed at the center of Typhoon Soulik.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in the ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Typhoon Soulik.  The strongest rainbands were occurring in the eastern half of the circulation.  Winds around the core Soulik were generating strong upper level divergence which was pumping mass away from the typhoon.

Typhoon Soulik has a large circulation.  Winds to typhoon force extend out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extend out about 230 miles (370 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Soulik was 20.6.  The Hurricane Size Index (HSI) was 23.5 and the Hurricane Wind Intensity Size Index (HWISI) was 44.1.

The large symmetrical structure of Typhoon Soulik will allow it to maintain its intensity for a longer period than a smaller tropical cyclone.  Soulik will move through an environment during the next 24 to 36 hours that will support a strong typhoon.  It will move over water where the Sea Surface Temperature is near 28°C.  It will move through an environment where the vertical wind shear will not be too strong.

Typhoon Soulik will move around the western end of ridge centered north of Japan.  The ridge will steer Soulik toward the northwest for another 24 to 36 hours.  On its anticipated track Typhoon Soulik will move over the northern Ryukyu Islands on Tuesday.  Soulik could approach South Korea within 36 hours.

Typhoon Cimaron brushed the northernmost Mariana Islands on Monday.  At 11:00 p.m. EDT on Monday the center of Typhoon Cimaron was located at latitude 20.5°N and longitude 144.5°E which put it about 90 miles (145 km) north-northwest of Agrihan.  Cimaron was moving toward the west-northwest at 14 m.p.h. (22 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 Cimaron is forecast to be near Iwo To in about 24 hours.  Cimaron could approach Honshu within 48 hours.  Upper level divergence from Typhoon Soulik is inhibiting the divergence on the western side of Cimaron.  The effects of Soulik will reduce the potential intensification of Typhoon Cimaron, but Cimaron could strengthen slowly during the next day or two.

Typhoon Soulik Moves Toward Ryukyu Islands, Cimaron Approaches Northern Marianas

Typhoon Soulik moved toward the northern Ryukyu Islands on Sunday and Typhoon Cimaron approached the Northern Mariana Islands.  At 11:00 p.m. EDT on Sunday the center of Typhoon Soulik was located at latitude 25.9°N and longitude 135.8°E which put it about 450 miles (730 km) east-southeast of Yaku Shima.  Soulik 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.

The structure of Typhoon Soulik changed on Sunday.  A large circular eye with a diameter or 45 miles (75 km) developed at the center of circulation.  A circular ring of thunderstorms surrounded the eye.  The ring was thinner on the western side of the eye and there may have been breaks in the ring.  Several bands of thunderstorms were revolving around the core of Typhoon Soulik.  Storms around the core were generating strong upper level divergence which was pumping mass away from the typhoon.  Winds to typhoon force extended out about 45 miles (75 km) from the center of circulation.  Winds to tropical storm force extended out about 195 miles (315 km) from the center.

Typhoon Soulik will move through an environment that should allow it to maintain its intensity for another day or two.  Soulik will move over water where the Sea Surface Temperature is near 29°C.  An upper level ridge north of Japan will produce easterly winds that will blow toward the top of the typhoon, but the winds will not cause significant vertical wind shear.  Typhoon Soulik could weaken a little, but it is likely to maintain most of its strength for another 24 to 48 hours.

Typhoon Soulik will move around the western end of the ridge north of Japan.  The ridge will steer Soulik toward the northwest for another 36 to 48 hours.  When Soulik reaches the western end of the ridge, it will turn toward the north.  On its anticipated track Typhoon Soulik could reach the northern Ryukyu Islands in about 36 hours.

At 11:00 p.m. EDT on Sunday the center of Typhoon Cimaron was located at latitude 17.3°N and longitude 148.5°E which put it about 240 miles (390 km) east-northeast of Saipan.  Cimaron was moving toward the west-northwest at 7 m.p.h. (11 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.  A Typhoon Warning was in effect for Agrihan, Pagan, Almagan.  A Tropical Storm Warning was in effect for Saipan and Tinian.

Typhoon Cimaron will move through an environment that could allow it to intensify during the next several days.  Cimaron will move over water where the Sea Surface Temperature is near 28°C.  Upper level divergence from Typhoon Soulik could inhibit the divergence generated by Cimaron on the northern side of the circulation.  Typhoon Cimaron is likely to intensify during the next day or two,

Typhoon Cimaron will move around the western end of a subtropical ridge.  The ridge will steer Cimaron toward the northwest during the next two or three days.  On its anticipated track Typhoon Cimaron will move over the Northern Marianas during the next 12 to 18 hours.  Cimaron could reach Iwo To within 48 hours and it could be south of Honshu in about three days.

Tropical Storm Cimaron Prompts Warnings for Northern Marianas, Soulik Strengthens West of Iwo To

Tropical Storm Cimaron developed east of the Northern Marianas on Saturday and it prompted Typhoon Warnings for some of the islands, while Typhoon Soulik strengthened west of Iwo To.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Cimaron was located at latitude 15.5°N and longitude 151.6°E which put it about 420 miles (675 km) east of Saipan.  Cimaron was moving toward the northwest 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 997 mb.  A Typhoon Warning was in effect for Agrihan, Pagan and Almagan.

A distinct center of circulation developed in an area of thunderstorms east of the Northern Marianas on Saturday and the Japan Meteorological Agency designated the system as Tropical Storm Cimaron.  Numerous bands of showers and thunderstorms developed around the circulation of Tropical Storm Cimaron.  The rainbands west and south of the center of circulation were stronger than the bands east and north of the center.  An inner bands of thunderstorms started to wrap around the south side of the center.  Storms near the center began to generate upper level divergence.

Tropical Storm Cimaron will move through an environment favorable for intensification during the next several days.  Cimaron will move over water where the Sea Surface Temperature is near 29°C.  Tropical Storm Cimaron will move through an area where it will be near the upper level divergence from Typhoon Soulik.  Tropical Storm Cimaron is forecast to stay just southeast of the divergence from Soulik.  If it does that, Cimaron will strengthen into a typhoon during the next few days.  However, if Cimaron moves under the upper level divergence from Typhoon Soulik, then the vertical wind shear will keep Cimaron from strengthening.

Typhoon Soulik strengthened into the equivalent of a major hurricane west of Iwo To on Saturday.  At 11:00 p.m. EDT on Saturday the center of Typhoon Soulik was located at latitude 25.2°N and longitude 138.8°E which put it about 145 miles (235 km) west-northwest of Iwo To.  Soulik was moving toward the west-northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (215 km/h).  The minimum surface pressure was 952 mb.

Typhoon Soulik is well organized.  There is a circular eye at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms.  Several bands of showers and thunderstorms are revolving around the core of Soulik.  Storms near the core are generating strong upper level divergence which is pumping mass away in all directions.  Winds to typhoon force extend out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extend out about 170 miles (280 km) from the center.

Typhoon Soulik will move through an area favorable for strong typhoons.  Soulik 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.  Soulik could maintain its intensity for another 24 to 48 hours.

Typhoon Soulik will move around the western end of a ridge in the middle troposphere.  The ridge will steer Soulik in a general northwesterly direction.  On it anticipated track Typhoon Soulik will move toward the Ryukyu Islands.  Tropical Storm Cimaron will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  On its anticipated track, Cimaron will move near the northern Marianas in 24 to 36 hours.  Tropical Storm Cimaron could approach Iwo To in about three days.

Tropical Storm Leepi Forms Southeast of Iwo To

Tropical Storm Leepi formed southeast of Iwo To on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Leepi was located at latitude 21.5°N and longitude 142.7°W which put it about 285 miles (465 km) south-southeast of Iwo To.  Leepi was moving toward the north-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 995 mb.

A distinct center of circulation developed within an area of thunderstorms between the Northern Marianas and Iwo To and the Japan Meteorological Agency designated the system as Tropical Storm Leepi.  The distribution of thunderstorms around Tropical Storm Leepi was very asymmetrical.  The stronger thunderstorms were all occurring in bands in the eastern half of the circulation.  The bands in the western half of the circulation consisted of showers and low clouds.  Storms near the center of Leepi were generating upper level divergence which was pumping mass away to the northeast of the tropical storm.

Tropical Storm Leepi will move through an environment somewhat favorable for intensification during the next 12 to 24 hours.  Leepi will move over water where the Sea Surface Temperature is near 29°C.  An upper level trough northeast of the tropical storm was producing southwesterly winds which were causing moderate vertical wind shear.  The wind shear was inhibiting the divergence to the west of Tropical Storm Leepi.  The tropical storm also appeared to be drawing drier air into the western side of the circulation.  Leepi could intensify on Sunday, but it will move into an area of stronger upper level winds in a day or so.  Increased vertical wind shear will likely start to weaken Tropical Storm Leepi after that occurrs.

Tropical Storm Leepi will move near the western end of a ridge in the middle troposphere.  The ridge will Leepi in a general motion toward the northwest.  On its anticipated track Tropical Storm Leepi will move near Iwo To in about 24 hours.  Leepi could approach the northern Ryukyu Islands and Kyushu in about three days.

Elsewhere over the Western North Pacific, Tropical Storm Yagi passed over the southern Ryukyu Islands on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Yagi was located at latitude 25.6°N and longitude 124.8°E which put it about 250 miles (400 km) east of Taipei, Taiwan.  Yagi was moving toward the west 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 993 mb.

Shanshan Strengthens to a Typhoon Southeast of Japan

Former Tropical Storm Shanshan strengthened into a typhoon southeast of Japan on Saturday.  At 5:00 a.m. EDT on Saturday the center of Typhoon Shanshan was located at latitude 21.2°N and longitude 148.5°E which put it about 245 miles (395 km) northeast of Agrihan.  Shashan was moving toward the north-northwest at 10 m.p.h. (16 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 975 mb.

A primary rainband wrapped around the center of circulation and an eye was developing at the center of Typhoon Shanshan.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Shanshan.  The strongest rainbands were south and east of the center of circulation.  Bands north and west of the center consisted primarily of showers and lower clouds.  Storms around the core were generating upper level divergence which was pumping mass away from the typhoon.  Shanshan has a large circulation.  Winds to tropical storm force extend out about 190 miles (305 km) from the center of circulation.

Typhoon Shanshan will move through an environment favorable for intensification during the next 24 to 48 hours.  Shanshan will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Shanshan will intensify and it could strengthen into the equivalent of a major hurricane.

Typhoon Shanshan will move around the western portion of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Shanshan in a north-northwesterly direction.  On its anticipated track the center of Typhoon Shanshan will pass east of Iwo To in 24 to 36 hours.  Shanshan could be just southeast of Honshu in about four days.

Tropical Storm Jongdari Makes Landfall South of Shanghai, Shanshan Forms Northeast of Guam

Tropical Storm Jongdari made landfall south of Shanghai on Thursday, while Tropical Storm Shanshan formed northeast of Guam.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Jongdari was located at latitude 30.7°N and longitude 121.4°E which put it about 40 miles (65 km) south of Shanghai, China.  Jongdari was moving toward the west at 19 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 994 mb.

The center of Tropical Storm Jongdari made landfall on the east coast of China near Zhoushan and Ningbo on Thursday.  Jongdari retained a distinct low level center of circulation while it made landfall.  The tropical storm brought gusty winds to the coast of Zhejiang and Shanghai Shi provinces.  Tropical Storm Jongdari dropped locally heavy rain over parts of those provinces and some flooding could occur.  The center of Jongdari will move quickly toward Hangzhou and the risk of flooding will continue as the tropical storm moves inland and weakens.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Shanshan formed northeast of Guam.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Shanshan was located at latitude 17.9°N and longitude 150.1°E which put it about 460 miles (740 km) northeast of Guam.  Shanshan was moving toward the west-southwest at 7 m.p.h. (11 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. (65 km/h).  The minimum surface pressure was 998 mb.

A distinct low level center of circulation formed in a cluster of thunderstorms east of the Northern Marianas on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Shanshan.  The circulation of Shanshan was still organizing.  Several bands of showers and thunderstorms developed southwest of the center of circulation.  Bands northeast of the center consisted mostly of showers and lower clouds.  Storms near the center of circulation started to generate upper level divergence.

Tropical Storm Shanshan will move through an environment favorable for intensification.  Shanshan will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Shanshan will intensify and it could strengthen into a typhoon during the weekend.

Tropical Storm Shashan will move around the western end of a subtropical high pressure system.  The high will steer Shanshan in a general northwesterly direction during the next 12 to 24 hours.  It will turn more toward the north during the weekend.  On its anticipated track Tropical Storm Shanshan will move near the Northern Marianas during the next 24 to 36 hours.

Tropical Depression 04W Forms East of the Northern Marianas

Tropical Depression 04W formed east of the Northern Marianas very late on Friday.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 04W was located at latitude 18.8°N and longitude 148.5°E which put it about 185 miles (300 km) east of Agrihan.  It was moving toward the northwest 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 1003 mb.

An area of showers and thunderstorms persisted for much of the past week east of the Northern Marianas.  Several smaller centers of circulation formed within the area of showers and storms, but those centers ran into strong upper level winds and weakened because strong vertical wind shear and they dissipated.  Another center formed on Friday, but the upper level winds were a little weaker and the center persisted.  An upper level trough south of Japan was still producing southwesterly winds which were blowing toward the top of the circulation.  Those winds were producing moderate vertical wind shear, but the center of circulation persisted.  Most of the thunderstorms were occurring in bands east of the center of circulation.  The bands west of the center consisted primarily of low clouds and showers.

Tropical Depression will move through an area marginally favorable for intensification during the next 24 hours.  it will move over water where the Sea Surface Temperatures are near 28°C.  So, there will be enough energy in the upper ocean to support some intensification.  The upper level trough south of Japan will continue to cause moderate vertical wind shear, but the upper level winds could be weak enough to allow for further intensification.  Tropical Depression 04W could strengthen into a tropical storm on Saturday.

Tropical Depression 04W is moving near the southwestern part of a ridge over the North Pacific Ocean.  The ridge is steering the depression toward the northwest and that general motion is expected to continue for another day or two.  On its anticipated track Tropical Depression 04W is expected to pass near the northernmost Mariana Islands.  It could pass near Asuncion Island, the Maug Islands, Supply Reef and Farallon de Pajaros.  Tropical Depression 04W could bring gust winds, locally heavy rain and higher waves to those places.