Tag Archives: Ryukyu Islands

Tropical Storm Nanmadol Brings Wind and Rain to Southern Ryukyu Islands

Tropical Storm Nanmadol brought wind and rain to the southern Ryukyu Islands on Sunday.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Nanmadol was located at latitude 24.4°N and longitude 124.7°E which put it about 40 miles (65 km) east of Ishigaki, Japan.  Nanmadol was moving toward the north-northwest at 21 m.p.h. (34 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 998 mb.

The core of Tropical Storm Nanmadol continued to organize on Sunday.  A ring of thunderstorms wrapped tightly around the center of circulation.  Additional bands of showers and thunderstorms formed outside the core.  Thunderstorms were beginning to generate more upper level divergence which was pumping out mass in all directions.  The circulation of Tropical Storm Nanmadol was fairly small.  Winds to tropical storm force only extend out about 70 miles (110 km) from the center.

Tropical Storm Nanmadol will be in an environment that is very favorable for intensification for about another 24 hours.  Nanmadol will be moving over water where the Sea Surface Temperature (SST) is near 29°C.  The circulation of Tropical Storm Nanmadol is underneath the center of an upper level ridge and the upper level winds are very weak.  Warm SSTs and almost no vertical wind shear will permit Tropical Storm Nanmadol to intensify during the next day and there could be a period of rapid intensification.  Nanmadol could strengthen into a typhoon before it reaches a less favorable environment.  The tropical storm will move over cooler SSTs and it will move into an area of stronger upper level westerly winds in a couple of days.  Nanmadol will begin to weaken when that happens.

Tropical Storm Nanmadol is moving around the western end of a subtropical ridge which is steering it toward the north.  A general northward motion is expected to continue for about another 24 hours.  Nanmadol will reach the westerly winds in the middle latitudes in about a day and those winds will turn it toward the northeast.  On its anticipated track the center of Tropical Storm Nanmadol will pass west of Okinawa.  Nanmadol could approach Kyushu in about 36 hours.  Tropical Storm Nanmadol will continue to cause gusty winds and locally heavy rain over the southern Ryukyu Islands for another 12 to 24 hours.

Tropical Storm Nanmadol Forms Southeast of Taiwan

Tropical Storm Nanmadol formed southeast of Taiwan on Saturday.  At 8:00 p.m. EDT on Saturday the center of Tropical Storm Nanmadol was located at latitude 20.7°N and longitude 127.1°E which put it about 475 miles (765 km) southeast of Taipei, Taiwan.  Nanmadol was moving toward the northwest at 24 m.p.h. (35 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 1002 mb.

A center of circulation consolidated rapidly on Saturday in an area of thunderstorms southeast of Taiwan.  A primary band of showers and thunderstorms wrapped around the northern and western side of the circulation.  Other bands of showers and thunderstorms developed in the northern half of the circulation.  The thunderstorms near the center began to generate upper level divergence which pumped out mass to the north of the tropical storm.

Tropical Storm Nanmadol will move through an area favorable for intensification during the next 24 hours.  Nanmadol will move over water where the Sea Surface Temperature is near 30°C.  An upper level ridge northeast of Nanmadol is producing southeasterly winds which are blowing toward the top of the tropical storm, but there is little vertical wind shear.  Tropical Storm Nanmadol is likely to intensify on Sunday.  When Nanmadol moves farther north, it will move over cooler water and it will be effected by the upper level westerly winds in the middle latitudes.  Cooler water and more vertical wind shear will cause Nanmadol to start to weaken at that time.

Tropical Storm Nanmadol is moving around the western end of a subtropical ridge which is steering it quickly toward the northwest.  Nanmadol will move in a general north-northwesterly direction on Sunday.  It will turn toward the northeast in 24 to 36 hours when it begins to be steered by the mid-latitude westerlies.  On its anticipated track Tropical Storm Nanmadol could approach the southernmost Ryukyu Islands including Ishigaki Jima in about 12 hours.  The center is expected to pass west of Okinawa.  Tropical Storm Nanmadol could approach Kyushu in a couple of days.  An intensifying Tropical Storm Nanmadol will bring gusty winds and locally heavy rain to the southernmost Ryukyu Islands.

Super Typhoon Chaba Threatens Japan and South Korea

Super Typhoon Chaba moved north on Monday and it threatened to bring strong winds and heavy rain to Japan and South Korea.  At 5:00 p.m. EDT on Monday the center of Super Typhoon Chaba was located at latitude 27.5°N and longitude 126.5°E which put it about 100 miles (160 km) west-northwest of Okinawa.  Chaba was moving toward the north at 11 m.p.h. (18 km/h).  The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 925 mb.

Typhoon Chaba is a compact well organized storm.  It has a clear circular eye surrounded by a ring of strong thunderstorms.  Winds to typhoon force extend out about 35 miles (55 km) from the center of circulation.  Additional rainbands are rotating around the core of Typhoon Chaba.  Thunderstorms at the core of Chaba are generating upper level divergence which is pumping mass out in all directions.

The Hurricane Intensity Index (HII) for Typhoon Chaba is 33.3.  The Hurricane Size Index (HSI) is 11.6 and the Hurricane Wind Intensity Size Index (HWISI) is 44.9.  These indices indicate that Typhoon Chaba is stronger, but slightly smaller than Hurricane Matthew which is over the Caribbean Sea.

Although Typhoon Chaba is still in a very favorable environment, it has probably peaked in intensity.  Chaba was the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale earlier today.  Chaba is currently moving over water where the Sea Surface Temperature (SST) is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  Typhoon Chaba is likely to weaken gradually during the next 24 hours.  In about a day or so, Chaba will move over cooler SSTs.  In addition, when Chaba moves farther north it will move closer to the upper level westerly winds in the middle latitudes.  A combination of cooler SSTs and more vertical wind shear will increase the rate at which Typhoon Chaba will weaken.

Chaba is moving around the western end of a subtropical ridge which is steering the typhoon toward the north.  That general motion is expected to continue for about another 24 hours.  In about a day or so the westerly winds of the middle latitudes are expected to turn Chaba quickly toward the northeast.  On its anticipated track the core of Typhoon Chaba will pass west of the northern Ryukyu Islands.  Chaba could be near Jeju, South Korea and western Kyushu in 24 hours.

Chaba is a very strong typhoon.  Although it will weaken, Typhoon Chaba will bring strong winds and heavy rain to parts of South Korea and Japan.

Powerful Typhoon Chaba Passing South of Okinawa

Powerful Typhoon Chaba is passing south of Okinawa.  At 11:00 p.m. EDT on Sunday the center of Typhoon Chaba was located at latitude 24.5°N and longitude 127.3°E which put it about 180 miles (290 km) south of Okinawa.  Chaba was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 145 m.p.h. (230 km/h) and there were wind gusts to 170 m.p.h. (280 km/h).  The minimum surface pressure was 935 mb.

The circulation of Typhoon Chaba is very well organized.  Chaba has a distinct circular eye surrounded by a ring of strong thunderstorms.  Other rainbands are rotating around the core of the circulation.  The thunderstorms in the core are generating upper level divergence which is pumping out mass to the north of Typhoon Chaba.

Typhoon Chaba is moving through a very favorable environment.  Chaba is moving over water where the Sea Surface Temperature (SST) is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  Typhoon Chaba could intensify a little more during the next 12 to 24 hours.  When Chaba moves farther north, an upper level trough over eastern China will cause more vertical wind shear.  Increased wind shear and cooler SSTs will weaken the typhoon.

Typhoon Chaba is moving around the western end of a subtropical ridge which is steering it toward the northwest.  Chaba will gradually start to move more toward the north.  In about 36 hours the upper level trough over eastern China will begin to steer Typhoon Chaba toward the northeast.  On its anticipated track Typhoon Chaba will move through the Ryukyu Islands southwest of Okinawa during the next 24 hours.  Chaba would be southwest of Kyushu in about 36 hours.

Chaba is a powerful typhoon and it will bring gusty winds and heavy rain to the Ryukyu Islands including Okinawa.

Typhoon Chaba Rapidly Intensifies Into the Equivalent of a Major Hurricane

Typhoon Chaba intensified rapidly into the equivalent of a major hurricane on Saturday.  At 11:00 p.m. EDT on Saturday the center of Typhoon Chaba was located at latitude 20.1°N and longitude 131.0°E which put it about 530 miles (855 km) south-southeast of Okinawa.  Chaba was moving toward the northwest at 19 m.p.h. (31 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 957 mb.

The organization of the circulation of Typhoon Chaba improved significantly on Saturday.  It has a small circular eye which is surrounded by a ring of very strong thunderstorms.  Another primary band of thunderstorms wrapped around the western side of the typhoon.  Thunderstorms in the core of Typhoon Chaba produced strong upper level divergence which pumped out enough mass to allow the pressure at the surface to decrease very rapidly during the past 24 hours.

Typhoon Chaba will continue to move in an environment that is very favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds are weak and there is not much vertical wind shear.  Typhoon Chaba should continue to intensify for another 24 hours and it could reach major typhoon status.

Typhoon Chaba is moving around the western end of a subtropical ridge which is steering the typhoon toward the northwest.  Chaba should start to move more toward the north when it reaches the western end of the ridge.  On its anticipated track Typhoon Chaba could reach Okinawa in about 36 hours.  It will be a powerful typhoon when it moves through the Ryukyu Islands.

Tropical Storm Chaba Organizes and Moves Toward Okinawa

Tropical Storm Chaba strengthened on Thursday as it started to move toward Okinawa.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Chaba was located at latitude 13.8°N and longitude 138.6°E which put it about 1145 miles (1850 km) southeast of Okinawa.  Chaba was moving toward the west 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 996 mb.

The circulation of Tropical Storm Chaba showed signs of better organization on Thursday.  A primary rainband wrapped around the western and south sides of the circulation.  Additional bands of thunderstorms were forming on the southern and eastern side of Tropical Storm Chaba.  Thunderstorms near the core of Chaba were generating upper level divergence which was pumping mass out to the west, south and east of the tropical storm.

Tropical Storm Chaba is moving into an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature (SST) is near 30°C.  An upper level ridge to the north of Chaba is generating easterly winds which are blowing across the northern portion of the tropical storm.  However, those winds are not causing significant vertical wind shear.  The combination of warm SSTs and little vertical wind shear should allow Tropical Storm Chaba to intensify steadily during the next several days.  It could become a typhoon within 24 to 48 hours.  There is a chance that Chaba could become the equivalent of a major hurricane in three or four days.

A subtropical ridge to the north of Chaba is steering the tropical storm toward the west and that general motion is expected to continue in the short term.  When Chaba gets a little closer to the western end of the ridge, it will start to move toward the northwest and when Chaba reaches the western end of the ridge it will turn toward the north.  On it anticipated track Tropical Storm Chaba could be approaching Okinawa and the Ryukyu islands in about three days.  It could be a powerful typhoon at that time.

Tropical Storm Chaba Forms East of Guam

A center of circulation developed within an area of thunderstorms east of Guam on Tuesday and the Japan Meteorological Agency designated the system as Tropical Storm Chaba.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Chaba was located at latitude 14.2°N and longitude 147.7°E which put it about 225 miles (360 km) east of Guam.  Chaba was moving toward the west at 17 m.p.h. (27 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 1000 mb.

The circulation of Tropical Storm Chaba is still organizing.  The distribution of thunderstorms is asymmetrical.  There are more thunderstorms east of the center of circulation.  Additional thunderstorms are forming west of the center of circulation and some rainbands are developing.  The thunderstorms near the center of Tropical Storm Chaba are generating upper level divergence which is pumping mass out in all directions.

Tropical Storm Chaba is moving through an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds are light and there is not significant vertical wind shear.  Tropical Storm Chaba is likely to continue to intensify as the circulation gets better organized.  Chaba could become a typhoon later this week.

A subtropical ridge to the north of Chaba is steering the tropical storm toward the west and that general motion is expected to continue for another 24 to 36 hours.  When Tropical Storm Chaba moves farther west, it will get closer to the western end of the subtropical ridge and Chaba is likely to turn more toward the west-northwest.  On its anticipated track Tropical Storm Chaba will move through the Marianas between Guam and Saipan and Tinian on Wednesday.  Chaba could be approaching Okinawa in about five days.

Powerful Typhoon Megi Nearing Landfall on Taiwan

Powerful Typhoon Megi is within a few hours of making landfall on the east coast of Taiwan.  At 11:00 p.m. EDT on Monday the center of Typhoon Megi was located at latitude 23.3°N and longitude 122.6°E which put it about 175 miles (280 km) southeast of Taipei, Taiwan.  Megi was moving toward the northwest at 15 m.p.h. (24 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 947 mb.

Megi is a large powerful typhoon and it is the equivalent of a major hurricane.  It has a big circular eye with a diameter of about 60 miles (95 km).  Winds to typhoon force extend out about 50 miles (80 km) from the center and winds to tropical storm force extend out over 200 miles (320 km) from the center.

The Hurricane Intensity Index (HII) for Typhoon Megi is 20.6.  The Hurricane Size Index (HSI) is 21.1 and the Hurricane Wind Intensity Size Index (HWISI) is 41.7.  Those indices suggest that Typhoon Megi is capable of causing widespread major wind damage.  The HII for Typhoon Megi is the same as the HII for Hurricane Rita when it made landfall in Louisiana in 2005.  The HSI for Megi is slightly smaller than the HSI for Rita.  Thus, Typhoon Megi is as intense as Hurricane Rita was when it made landfall, but Megi is slightly smaller than Rita was in 2005.

A subtropical ridge is steering Typhoon Megi toward the northwest.  Typhoon Megi will make landfall on the east coast of Taiwan near Hualien in a few hours.  Megi will cross Taiwan and it will make a second landfall on the east coast of China near Quanzhou and Xiamen in about 24 hours.  Typhoon Megi will bring strong winds and very heavy rain to the northern two thirds of Taiwan.  The heavy rain will create a serious risk for flash flooding.  Megi will weaken as it crosses Taiwan,   Typhoon Megi will also bring gusty winds and heavy rain when it reaches the east coast of China.  Typhoon Meranti caused serious damage in parts of Fujian province and Typhoon Megi will bring heavy rain to some of those same areas.  The northern side of Typhoon Megi may also bring gusty winds to the southernmost Ryukyu Islands.

Typhoon Megi Strengthens As It Moves Closer to Taiwan

Typhoon Megi strengthened quickly on Saturday as it moved steadily closer to Taiwan.  At 11:00 p.m. EDT on Saturday the center of Typhoon Megi was located at latitude 19.4°N and longitude 131.0°E which put it about 685 miles (1105 km) east-southeast of Taipei, Taiwan.  Megi was moving toward the west northwest at 14 m.p.h. (22 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 963 mb.

Megi is a large well organized typhoon.  Winds to typhoon force extend out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extend out more than 200 miles (320 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Megi is 17.8.  The Hurricane Size Index (HSI) is 18.7 and the Hurricane Wind Intensity Size Index (HWISI) is 36.5.

The circulation of Typhoon Megi is very symmetrical.  Numerous bands of thunderstorms are rotating around the center.  A circular eye appears to be forming at the center of circulation.  Thunderstorms near the center and in the rainbands are generating upper level divergence which is pumping out large quantities of mass in all directions.

Typhoon Megi is moving through a very favorable environment.  It is moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  Typhoon Megi is likely to continue to intensify and it could become the equivalent of a major hurricane on Sunday.

Typhoon Megi is moving southwest of a subtropical ridge which is steering it toward the west-northwest and that general motion is expected to continue for several more days.  On its anticipated track Typhoon Megi will approach Taiwan in about 48 hours.

Typhoon Megi is large and dangerous typhoon.  It is likely to bring strong winds and heavy rain to Taiwan.

Tropical Storm Megi Forms West of the Marianas

Tropical Storm Megi formed west of the Marianas on Friday.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Megi was located at latitude 16.4°N and longitude 137.1°E which put it about 1160 miles (1870 km) east-southeast of Taipei, Taiwan.  Megi was moving toward the west at 15 m.p.h. (24 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/).  The minimum surface pressure was 996 mb.

The circulation of Tropical Storm Megi is still organizing.  A distinct center of circulation is still consolidating.  There are more thunderstorms south and east of the center of circulation, but bands of thunderstorms are beginning to develop in other quadrants of the storm.  The thunderstorms closer to the center are generating upper level divergence which is pumping out mass.  Outflow channels could be developing to the northwest and southeast of Tropical Storm Megi.

Tropical Storm Megi is moving into an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds are not very strong and there is little vertical wind shear.  Tropical Storm Megi is likely to continue to intensify while the circulation becomes better organized.  Once a well formed core develops at the center of Megi, it could intensify more rapidly.  Tropical Storm Megi is likely to become a typhoon during the weekend.

Tropical Storm Megi is moving along the southwestern side of a subtropical ridge, which is steering it toward the west.  A westerly or west-northwesterly motion is expected to continue for the next few days.  On its anticipated track Tropical Storm Megi could approach Taiwan in about three days.  Megi is likely to be a typhoon at that time.