Tag Archives: Philippines

Typhoon Koppu Continues to Intensify and Threaten Luzon

Typhoon Koppu continued to intensify on Friday and it maintained its steady course toward northern Luzon.  At 5:00 p.m. EDT on Friday the center of Typhoon Koppu was located at latitude 15.8°N and longitude 124.5°E which put it about 270 miles (435 km) east-northeast of Manila, Philippines.  Koppu was moving toward the west at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 947 mb.

Typhoon Koppu is evolving into a large well organized typhoon.  An eye has formed at the center of the circulation and multiple rain bands spiral around the core of the typhoon.  Upper level divergence is pumping mass away from the center of circulation.  Koppu is moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds are light and there is not much vertical wind shear.  Koppu is likely to continue to intensify until it begins to interact with northern Luzon.

A subtropical ridge is steering Koppu toward the west and that steering pattern is expected to continue for another 24 to 36 hours.  On its anticipated track the center of Typhoon Koppu will be very near the northeastern coast of Luzon in about 24 hours.  Koppu will bring strong winds, heavy rain and a storm surge to northern Luzon.  The large size of Koppu and its relatively slow movement means that it could produce very heavy rainfall.  Serious flooding and numerous mudslides are possible across northern Luzon.

Intensifying Typhoon Koppu Moving Toward Northern Luzon

Typhoon Koppu intensified on Thursday as it continued to move steadily toward Northern Luzon.  At 11:00 p.m. EDT the center of Typhoon Koppu was located at latitude 15.6°N and longitude 126.9°E which put it about 425 miles (685 km) east of Manila, Philippines.  Koppu was moving toward the west at 8 m.p.h. (13 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 969 mb.

Typhoon Koppu is moving over water where the Sea Surface Temperature is near 30°C.  The upper level winds lessened on Thursday which decreased the vertical wind shear and allowed Koppu to intensify more quickly.  The core of the circulation consolidated and there are suggestions that an eyewall may be forming.  Koppu is expected to move through a favorable environment until it reaches northern Luzon and further intensification is very likely.

A subtropical ridge is steering Koppu toward the west and that general steering pattern is expected to continue for another 36 to 48 hours.  On its anticipated track, Typhoon Koppu will approach northern Luzon in 36 to 42 hours.  It could bring strong winds, heavy rain and a storm surge when it reaches that area.  The heavy rain could produce floods and mudslides as Koppu moves over northern Luzon.

Tropical Storm Koppu Forms North of Yap

In spite of significant vertical wind shear a surface circulation has been consolidating inside an area of thunderstorms north of Yap.  The system has been designated Tropical Storm Koppu.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Koppu was located at latitude 15.7°N and longitude 137.1°E which put it about 430 miles (690 km) north of Yap.  Koppu was moving toward the west at 14 m.p.h. (23 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 993 mb.

Significant vertical wind shear is inhibiting the organization of Tropical Storm Koppu.  An upper level ridge north of Koppu is generating strong northeasterly winds over the top of the tropical storm.  The vertical wind shear is causing most of the strong thunderstorms to be located southwest of the center of circulation.  The only other deep convection is occurring in a band that is west of the core of the circulation.

Koppu is over water where the Sea Surface Temperature is near 30°C and so there is plenty of energy in the upper ocean.  The wind shear will inhibit intensification for another 24 to 48 hours before it starts to subside.  Koppu could intensify much more quickly later this week when it moves into an area where the upper level winds are lighter.  Koppu could become a typhoon withing 36 to 48 hours and it could be a strong typhoon by the end of the week.

A subtropical ridge is steering Tropical Storm Koppu quickly to the west.  That general motion is expected to continue for the rest of the week.  On its anticipated track Koppu could be approaching northern Luzon in about three or four days.  It could be a significant typhoon by that time.

Tropical Storms Mujigae and Choi-Wan Form Over NW Pacific

Two new tropical storms with the names of Mujigae and Choi-Wan have formed over the western North Pacific Ocean.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Mujigae was located at latitude 17.4°N and longitude 117.3°E which put it about 275 miles (445 km) northwest of Manila, Philippines.  Mujigae was moving toward the west-northwest at 17 m.p.h.  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 990 mb.

At 11:00 a.m. EDT on Friday the center of Tropical Storm Choi-Wan was located at latitude 19.2°N and longitude 166.4°E which put it about 15 miles (20 km) south-southeast of Wake Island.  Choi-Wan was moving toward the west-northwest at 3 m.p.h. (5 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 996 mb.

Tropical Storm Mujigae organized quickly after the system move west of the Philippines.  A primary curved rainband wrapped around the western and southern sides of the center of circulation.  A possible eye is apparent intermittently on infrared satellite imagery.  Upper level divergence is beginning to occur both north and south of the center.  Mujigae is moving over water where the Sea Surface Temperature is near 28°C and there is not enough vertical wind shear to prevent intensification.  A period of rapid intensification is possible and Mujigae could become a typhoon in 12 to 24 hours.

A subtropical ridge is steering Mujigae toward the west-northwest and that general motion is expected to continue for the next several days.  On its anticipated track, Mujigae could be approaching the southern coast of China in 36 hours.  It could bring strong winds and heavy rain when it makes landfall.

Tropical Storm Choi-Wan is still in the organizational stage.  It has a large broad circulation without a well developed inner core.  Winds to tropical storm force are occurring in clusters of thunderstorms.  Choi-Wan is over Sea Surface Temperatures near 29°C, but there is moderate vertical wind shear over the northern part of the tropical storm.  The wind shear is expected to decrease in a day or two and Choi-Wan is forecast to become a typhoon.

Choi-Wan is between two subtropical ridges and the steering currents are relatively weak.  In a day or two the western ridge is expected to steer Choi-Wan toward the northwest.  Choi-Wan will cause squally weather on Wake Island for 24 to 48 hours.

Typhoon Goni Turning North, May Threaten Okinawa

Typhoon Goni is slowly turning toward the north and moving away from northern Luzon.  At 5:00 p.m. EDT on Friday the center of Typhoon Goni was located at latitude 19.8°N and longitude 122.5°E which put it about 330 miles (530 km) south-southeast of Taipei, Taiwan and about 615 miles (990 km) southwest of Okinawa.  Goni was moving toward the north at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 105 m.p.h. (120 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 956 mb.

Typhoon Goni will still be moving over warm Sea Surface Temperatures for the next several days and it has a chance to intensify.  The upper level winds are relatively light over the typhoon and there is not much vertical wind shear along its immediate path.  There appears to be an upper level outflow channel to the northeast.  Given the favorable environment Goni could intensify on Saturday.

Goni is moving around the western end of a subtropical high pressure system and it should begin to move toward the northeast a little more quickly.  On its anticipated track Goni could be near Ishigaki Jima in about 36 hours and near Okinawa in about 48 hours.  It could still be a strong typhoon at that time.  Goni could still by a typhoon when it approaches southwestern Kyushu in about three days.

Typhoon Goni Moving Closer to Northern Luzon and Taiwan

Typhoon Goni moved steadily westward on Wednesday and it got closer to northern Luzon and Taiwan.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Goni was located at latitude 18.9°N and longitude 125.3°E which put it about 350 miles (565 km) southeast of Taipei, Taiwan.  Goni was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 937 mb.

Typhoon Goni intensified on Wednesday and it is a very well organized tropical cyclone.  It has a large well formed eye.  The circulation is symmetrical although there are more thunderstorms in the south half of the typhoon.  Upper level divergence is well developed and it is pumping out mass in all directions.  Goni remains over warm Sea Surface Temperatures and the upper level winds are relatively light.  Some further intensification is possible during the next day or so.  Goni could run into stronger upper level winds in two or three days which would create more vertical wind shear and start to weaken the typhoon.

A subtropical ridge has been steering Goni toward the west and it is expected to do so again on Thursday.  However, Goni is nearing the western end of the ridge and it is forecast to turn to the north on Friday.  Goni appears to have moved more slowly during the past few hours, which may be an indication that it is reaching the western end of the ridge.  An upper level trough northwest of Goni is expected to turn Goni toward the northeast during the weekend and then accelerate it toward western Japan.

On its anticipated track, the center of Goni is expected to pass northeast of Luzon.  However, the circulation is large enough that some of northern Luzon could experience strong winds and heavy rain.  The center of Goni is forecast to pass east of Taiwan, but it could also bring strong winds heavy rain to some locations there as well.  The core of Goni could pass very near Ishigaki Jima and bring very strong winds and heavy rain to the islands in that area.

Typhoon Goni Heading West

Typhoon Goni moved steadily westward away from the Mariana Islands on Monday.  At 11:00 p.m. EDT on Monday the center of Typhoon Goni was located at latitude 18.3°N and longitude 135.3°E which put it about 780 miles (1260 km) southeast of Okinawa.  Goni was moving toward the west at 19 m.p.h. (31 km/).  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 944 mb.

Goni appeared to go through an eyewall replacement cycle on Monday which resulted in a reduction in the maximum wind speed.  As the tiny pinhole inner eye weakened, the stronger winds were located in the larger outer eyewall.  The reduction in wind speed could be temporary, if the outer eye begins to contract.  Goni remains in a favorable environment.  It is moving over warm Sea Surface Temperature and the vertical wind shear is very modest.  The circulation is producing upper level divergence in all directions.  Goni will remain in a favorable environment for another two or three days and it should remain strong during that time period.

A subtropical ridge is steering Goni toward the west-northwest and that steering pattern is expect to continue for another 48 to 72 hours.  Later this week an upper level trough could approach the typhoon from the northwest.  Southwesterly winds on the eastern side of the trough could turn Goni toward the north later this week. On its anticipated track Goni could be near Taiwan, the northern Philippines or Okinawa when it makes that turn.

Goni Intensifies Rapidly Into a Strong Typhoon

Goni intensified rapidly from a tropical storm into a strong typhoon on Sunday.  At 11:00 p.m. EDT on Sunday the center of Typhoon Goni was located at latitude 16.7°N and longitude 141.1°E which put it about 265 miles (425 km) west of Anatahan.  Goni was moving toward the west-northwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) which made Goni the equivalent of a major hurricane.  There were wind gusts to 160 m.p.h. (260 km/h) and the minimum surface pressure was 937 mb.

The circulation of Goni organized quickly on Sunday and it was able to intensify rapidly.  The primary rainband wrapped tightly around the center of circulation and a tiny pinhole eye formed in the center.  The band continued to wrap about the core of the circulation and it could be about to form a second, larger concentric eyewall.  The structure of Goni looks a lot like the circulation of Typhoon Soudelor did when it intensified rapidly.  Light easterly winds in the upper levels enhanced divergence to the west of Goni and pumped out mass allowing the pressure to fall rapidly.

Goni is moving over water where the Sea Surface Temperatures are warm.  The vertical wind shear is minimal and further intensification is possible.  If concentric eyewalls form, eyewall replacement cycles could produce fluctuations in intensity.

A subtropical ridge is steering Goni toward the west-northwest and that general steering pattern is expected to continue for another three or four days.  At that time Goni could be near the western end of the subtropical ridge.  An upper level trough in the mid-latitude westerlies could approach the typhoon from the northwest and turn it toward the north.

Tropical Storm Linfa Heading for Taiwan

Tropical Storm Linfa crossed northern Luzon and turned for Taiwan on Sunday.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Linfa was located at latitude 19.0°N and longitude 119.4°E which put it about 230 miles (370 km) south-southwest of Hengchun, Taiwan.  Linfa was moving toward the north-northwest at 7 m.p.h. (11 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 992 mb.

The circulation of Tropical Storm Linfa was relatively intact after it crossed northern Luzon and it moved back over water.  However, an upper level ridge over eastern Asia generated northeasterly winds that were strong enough to blow the top off of the circulation.  Strong upper level wind shear is making it difficult for new thunderstorms to form near the center of circulation.  Although Linfa will be moving over warm water, the wind shear will limit intensification.

Linfa has reached the western end of the subtropical ridge that has been steering the tropical storm.  It has turned toward the north and that general movement is expected to continue.  On its anticipated track Linfa could approach southern Taiwan in about two days.  It could bring locally heavy rain to parts of Taiwan.

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.