Tag Archives: Japan

Chan-hom Intensifies Into a Typhoon

The circulation around Chan-hom organized rapidly on Monday and it intensified into a typhoon.  At 11:00 p.m. EDT on Monday the center of Typhoon Chan-hom was located at latitude 18.1°N and longitude 136.8°E which put it about 850 miles (1370 km) southeast of Okinawa.  Chan-hom was moving toward the west at 11 m.p.h. (18 km/h).  The maximum sustained wind speed was 85 m.p.h. (140 km/h) and there were wind gusts to 105 m.p.h. (170 km/h).  The minimum surface pressure was 967 mb.

A primary rainband wrapped completely around the center of circulation of Typhoon Chan-hom and a large eye is apparent on satellite images.  Strong thunderstorms around the eye are generating upper level divergence which is pumping out mass and allowing the surface pressure to decrease.  The typhoon is over water where the Sea Surface Temperature is around 28°C and there is plenty of energy in the upper ocean.  Upper level winds are relatively light and there is not much vertical wind shear.  The environment is very favorable for further intensification and rapid intensification is possible.  Chan-hom is expected to continue to intensify and it could become the equivalent of a major hurricane later this week.

A subtropical ridge north of Chan-hom is steering the typhoon toward the west.  The ridge is expected to steer Chan-hom toward the northwest during the next few days.  On its anticipated track Typhoon Chan-hom could approach the southern islands of Japan in about three days.  It could be a large and powerful typhoon at that time.

Tropical Storm Chan-hom Moving Away From the Marianas

Tropical Storm Chan-hom continued to move farther west of the Mariana Islands on Sunday.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Chan-hom was located at latitude 16.6°N and longitude 142.0°E which put it about 1170 miles (1890 km) southeast of Okinawa.  Chan-hom was moving toward the north-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 982 mb.

The circulation around Tropical Storm Chan-hom became a little better organized on Sunday.  A primary band of thunderstorms wrapped around the southern half of the circulation.  There also appears to be some drier air wrapping into the circulation as well.  The upper level winds have decreased and some upper level divergence appears to be developing.  Chan-hom is over water there the Sea Surface Temperature is near 28°C.  With the exception of the drier air the environment is favorable for intensification Chan-hom is expected to become a typhoon.

A subtropical ridge is steering Chan-hom in a generally northwesterly direction and that steering pattern is expected to continue for the next few days.  On its anticipated track Chan-hom could approach Okinawa in three or four days.

Tropical Storm Chan-hom Bringing Wind and Rain to Guam

Tropical Storm Chan-hom is passing through the Marianas and bringing gusty winds and rain to Guam and Rota.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Chan-hom was located at latitude 14.3°N and longitude 144.8°E which put it about 10 miles (15 km) west of Rota.  Chan-hom was moving toward the west-northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 45 m.p.h. (70 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 991 mb.

Despite being over warm water Chan-hom did not intensify on Saturday.  The circulation could be pulling in some drier air which is limiting the development of thunderstorms.  More thunderstorms developed near the inner core of Chan-hom late on Saturday.  There is not much vertical wind shear over the tropical storm.  If a well organized inner core forms, then intensification will be possible.  Chan-hom could become a typhoon after it moves west of the Mariana Islands.

The subtropical ridge steering Chan-hom is expected to continue to steer it toward the northwest during the next few days.  On its anticipated track Chan-hom could approach the southern islands of Japan in about four days.

Tropical Storm Linfa Makes Landfall in Northern Luzon

Tropical Storm Linfa made landfall in northern Luzon on Saturday.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Linfa was located at latitude 17.8°N and longitude 121.7°E which put it near Tuguegarao, Philippines.  Linfa was moving toward the west at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 m.p.h.) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 989 mb.   Linfa is bringing gusty winds and locally heavy rain to parts of northern Luzon.

Linfa should continue to weaken during the next 12 to 18 hours while the center is over land.  If the circulation is intact when it moves back over water, then the tropical storm may intensify once it gets north of the Philippines.  Linfa will soon reach the western end of a subtropical ridge which has been steering it toward the west.  When Linfa reaches the end of the ridge, it will likely turn toward the north.  The tropical storm could approach Taiwan in 48 to 72 hours.

Tropical Storm Linfa Nearing Northern Luzon

Tropical Storm Linfa is moving steadily toward the coast of northern Luzon.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Linfa was located at latitude 16.1°N and longitude 123.9°E which put it about 230 miles (370 km) east-northeast of Manila, Philippines.  Linfa was moving toward the northwest at 9 m.p.h. (15 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 989 mb.

Tropical Storm Linfa has a small circulation, but it appears to be intensifying quickly.  A circular area of strong thunderstorms has developed around the center of circulation and it is producing strong upper level outflow.  Linfa is over water where the Sea Surface Temperature is near 30°C.  An upper level ridge northwest of the tropical storm is producing some vertical wind shear, but the shear does not seem to be enough to prevent intensification.  Linfa has about 18 hours to intensify before it reaches the coast of Luzon and it could attain typhoon intensity before it gets there.  Mountains in northern Luzon will disrupt the lowers levels of the circulation and Linfa will weaken after if makes landfall.

A subtropical ridge is steering Linfa toward the northwest and that steering pattern is expected to continue until the tropical storm makes landfall in northern Luzon.   Linfa will reach the western end of the subtropical ridge while it is over Luzon and if the circulation remains intact vertically, it will turn toward the north.  On its anticipated track Linfa will make landfall in northern Luzon in about 18 hours.  It is expected to eventually turn north toward Taiwan and the southern islands of Japan.  Linfa cold bring strong winds and locally heavy rainfall for parts of northern Luzon.  Heavy rainfall could contribute to flooding and mudslides in some locations.

Tropical Storm Chan-hom Moving Toward Marianas

Tropical Storm Chan-hom has resumed a northwesterly motion and it is moving toward the Mariana Islands.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Chan-hom was located at latitude 12.7°N and longitude 148.2°E which put it about 250 miles (400 km) east-southeast of Guam.  Chan-hom was moving toward the northwest at 11 m.p.h. (18 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 989 mb.  A Typhoon Watch is in effect for Guam, Rota, Tinian and Saipan.

The upper level low that produced the vertical wind shear which blew the top off Chan-hom on Thursday moved northeast and the upper level winds decreased on Friday.  A reduction in vertical wind shear allowed new thunderstorms to develop around the center of circulation and the circulation became better organized.  The thunderstorms near the center are beginning to generate upper level divergence and more spiral bands appear to be forming.  Chan-hom is over water where the Sea Surface Temperature is near 29°C.  The environment is favorable for intensification and rapid intensification is possible, if the wind shear remains modest.  Chan-hom could attain typhoon intensity before it reaches the Mariana Islands.

A subtropical ridge is steering Chan-hom toward the northwest and that ridge is expected to continue to steer it in the same general direction during the next few days.  On its anticipated track, Chan-hom could approach the Mariana Islands in about 24 hours.  The center could pass north of Guam, but it may pass near to Rota, Tinian or Saipan.  Chan-hom will bring wind and heavy rain to any islands it crosses.

Wind Shear Affecting Tropical Storm Chan-hom

Although Tropical Storm Chan-hom briefly reached typhoon intensity on Thursday, strong upper vertical wind shear quickly weakened it back to a tropical storm.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Chan-hom was located at latitude 10.3°N and longitude 148.0°E which put it about 325 miles (525 km) southeast of Guam.  Chan-hom was moving toward the west at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 981 mb.  A Typhoon Watch has been issued for Guam, Rota, Tinian and Saipan.

The combination of a upper level ridge and an upper level low produced strong northeasterly winds that blew the middle and upper portions of the circulation of Chan-hom west of the low level circulation.  The middle and upper parts of the circulation are about 100 miles (160 km) southwest of the surface center.  There are no thunderstorms currently near the surface center.  The upper level winds and the vertical wind shear they are producing are likely to continue to weaken Chan-hom on Friday.  The upper low is expected to move eastward during the next several days, which would result in a decrease in the wind shear.  If the surface circulation is still intact, it will be over warm Sea Surface Temperatures and reintensification would be possible.

Chan-hom is likely to be steered toward the west on Friday by the winds in the lower levels.  If new thunderstorms develop near the center and the height of the circulation increases, then a subtropical ridge in the middle levels could cause the tropical storm to turn toward the northwest.  If that turn occurs on Friday, it could put Chan-hom on a track toward Guam, Saipan or Tiniana.  If the turn occurs later in the weekend, then Chan-hom could pass to the south of those islands before it turns toward the northwest.

Typhoon Dolphin Is Bringing Wind and Heavy Rain to Iwo To

Even though the center of Typhoon Dolphin is still over 100 miles from Iwo To, it is bringing wind and heavy rain to that island.  The most recent surface observation reported southeast winds at 43 m.p.h. with gusts to 66 m.p.h.  At 11:00 p.m. EDT on Monday the center of Typhoon Dolphin was located near latitude 24.6° and longitude 139.7°E which put it about 140 miles west-southwest of Iwo To.  Dolphin was moving toward the northeast at 10 m.p.h.  The maximum sustained wind speed was 85 m.p.h. and there were gusts to 105 m.p.h.  The minimum surface pressure was 967 mb.

Dolphin will continue to move over cooler Sea Surface Temperatures as it moves farther north.  It will also encounter strong upper level westerly winds, which will increase vertical wind shear.  So, Typhoon Dolphin will weaken steadily on Tuesday.  It will eventually transition into an extratropical cyclone as it passes southeast of Japan.

Upper level westerly winds are steering Typhoon Dolphin toward the northeast.  It is expected to accelerate toward the northeast on Tuesday.  On its anticipated track the center of Dolphin will pass northwest of Iwo To during the next few hours.  It could pass very near Chichi Jima on Tuesday and bring strong wind and heavy rain.

Typhoon Dolphin Approaching Iwo To

Although Typhoon Dolphin is weakening, it will still be a typhoon when it approaches Iwo To in about 24 hours.  At 11:00 p.m. EDT on Sunday the center of Typhoon Dolphin was located at latitude 21.3°N and longitude 138.7°E which put it about 320 miles south-southwest of Iwo To.  Dolphin was moving toward the north at 10 m.p.h.  The maximum sustained wind speed was 125 m.p.h. and there were gusts to 155 m.p.h.  The minimum surface pressure was 941 mb.

Upper level westerly winds blowing over the top of Dolphin are tilting the circulation to the east and contributing to the weakening of the typhoon.  Dolphin will soon be moving over water where the Sea Surface Temperature (SST) is lower than 26°C and as it moves farther north it will encounter stronger upper level westerly winds.  Cooler SSTs and more vertical wind shear will continue to weaken Dolphin.  As it moves into a cooler environment southeast of Japan in several days, Dolphin will make a transition to an extratropical cyclone.

Dolphin is moving around the the western end of a subtropical ridge.  It will gradually turn more toward the northeast on Monday.  As it encounters stronger westerly winds, Dolphin will start to move more rapidly toward the northeast.  On its anticipated track, Dolphin will near Iwo To in about 24 hours.  Although it will be weaker, it will still be a typhoon at that time.

 

Typhoon Dolphin Becomes Equivalent of Category 5 Hurricane

Typhoon Dolphin intensified rapidly on Saturday and it reached an intensity equivalent to a Category 5 hurricane on the Saffir-Simpson Scale.  At 11:00 p.m. EDT on Saturday the center of Typhoon Dolphin was located at latitude 18.3°N and longitude 139.0E which put it about 470 miles south-southwest of Iwo To.  Dolphin was moving toward the northwest at 12 m.p.h.  The maximum sustained wind speed was 160 m.p.h. and there were gusts to 195 m.p.h.  The minimum surface pressure was 918 mb.

Dolphin is moving over water where the Sea Surface Temperatures (SSTs) are between 26°C and 27°C.  It is in an area where the upper level winds are light and there is not much vertical wind shear.  It has very well developed upper level outflow, especially on the northeast side of the circulation.  Dolphin developed concentric eyewalls earlier on Saturday, but the inner eyewall appears to have dissipated.  The circulation has consolidated around the outer eyewall and it is now the core of the circulation.  Dolphin is probably near its peak intensity.  As it moves farther north, the SSTs will decrease and it will move over water cooler than 26°C.    In addition, upper level westerly winds will increase as the typhoon moves north of 25°N.  Cooler SSTs and more vertical wind shear will produce a steady weakening of Dolphin as it moves north.

Dolphin is moving around the western end of a subtropical ridge.  It is likely to move northward on Sunday and then turn to the northeast on Monday.  As it encounters westerly winds early next week, it is likely to accelerate toward the northeast.  On its anticipated track Dolphin will approach Iwo To in about 48 hours.  It could still be a significant typhoon at that time.