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Tropical Storm Pakhar Makes Landfall Near Macau

Tropical Storm Pakhar sped across the South China Sea and made landfall on the coast of China near Macau.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Pakhar was located at latitude 22.3°N and longitude 112.7°E which put it about 60 miles (95 km) southwest of Hong Kong.  Pakhar was moving toward the northwest at 27 m.p.h. (43 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 987 mb.

Tropical Storm Pakhar will bring gusty winds and locally heavy rain as it quickly moves inland over southern China.  The wind and rain will hinder the efforts in the area to recover from Typhoon Hato.  Fortunately, Tropical Storm Pakhar is a fairly small storm.  Winds to tropical storm force only extend out about 80 miles (130 km) from the center of circulation.  The small size of Pakhar and its rapid rate of movement will limit the impact of the tropical storm.  Tropical Storm Pakhar should spin down fairly quickly as it rapidly moves inland.

Tropical Storm Pakhar Forms East of Luzon

Tropical Storm Pakhar formed east of Luzon on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Pakhar was located at latitude 15.2°N and longitude 124.7°E which put it about 280 miles (455 km) east of Manila, Philippines.  Pakhar was moving toward the west at 13 m.p.h. (21 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.

A center of circulation developed on the eastern edge of a cluster of thunderstorms east of Luzon on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Pakhar.  The circulation of Pakhar is still in the early organizational stages.  Most of the showers and thunderstorms are occurring west of the center of circulation.  An upper level ridge north of Pakhar is producing easterly winds which are blowing across the circulation.  Those easterly winds are probably responsible for the asymmetrical distribution of thunderstorms on the western side of the tropical storm.

Tropical Storm Pakhar will move through an environment that will be somewhat favorable for intensification during the next 12 to 18 hours.  Pakhar will move over water where the Sea Surface Temperature (SST) is near 30°C.  The easterly winds in the upper levels are causing moderate vertical wind shear and the shear will inhibit intensification.  Tropical Storm Pakhar will weaken when it moves across Luzon.  After Pakhar moves out over the South China Sea, it will move back over water where the SST is near 30°C.  The forecast suggests that there could be less vertical wind shear at that time and Pakhar has a chance to intensify into a typhoon when it moves away from the Philippines.

Pakhar is being steered westward by a subtropical ridge north of the tropical storm.  Pakhar is forecast to turn more toward the northwest when it crosses Luzon.  On its anticipated track Tropical Storm Pakhar will reach the coast of Luzon near Baler in 12 to 18 hours.  Pakhar is forecast to continue moving toward the northwest and it could make another landfall in China west of Hong Kong in about three days.  However, there is more uncertainty about the future track of Pakhar after the tropical storm exits Luzon.

Tropical Storm Pakhar could bring heavy rain to Luzon and cause flooding in some locations.  If Tropical Storm Pakhar intensifies over the South China Sea and makes landfall west of Hong Kong as a typhoon, it could seriously affect the efforts to recover from damage caused by Typhoon Hato which hit that same area a few days ago.

Strong Typhoon Meranti Nears Landfall in China

Strong Typhoon Meranti is near a landfall on the east coast of China close to Xiamen.  At 11:00 a.m. EDT on Wednesday the center of Typhoon Meranti was located at latitude 23.9°N and longitude 118.4°E which put it about 40 miles (65 km) south-southeast of Xiamen, China.  Meranti was moving toward the northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 931 mb.

Meranti has weakened during the past 24 hours, but it remains a strong typhoon.  The Hurricane Intensity Index (HII) for Typhoon Meranti is 29.9.  The Hurricane Size Index (HSI) is 24.5 and the Hurricane Wind Intensity Size Index is 54.4.  These indices suggest that Typhoon Meranti is capable of causing widespread significant damage when it makes landfall.  As a comparison, the HII for Hurricane Ivan just before it made landfall on the Gulf Coast in 2004 was 22.1, the HSI was 34.1 and the HWISI was 56.2.  Thus, Typhoon Meranti is stronger than Hurricane Ivan was, but Meranti is also smaller than Ivan was in 2004.  The HWISI for Typhoon Meranti is close to what it was for Hurricane Ivan.

The center and inner eyewall of Typhoon Meranti moved just south of the southern end of Taiwan.  Since the eyewall stayed over water, it remained intact.  However, the outer concentric eyewall and much of the northern half of the circulation did move across Taiwan.  Flow over the mountains on Taiwan did weaken the northern half of the circulation, while the center and southern half of the circulation remained intact.  Since the core of the circulation stayed over the water, Typhoon Meranti stayed stronger than it would have if the inner eye had moved over Taiwan.

Most of the stronger thunderstorms and heavier rain are near the center of circulation and south of the center.  There are rainbands in other parts of Typhoon Meranti and some of those rainbands are already bringing heavy rain to parts of eastern China.

Typhoon Meranti is moving around the western end of a subtropical ridge which is steering it toward the northwest.  Meranti is expected to turn more toward the north as it move inland over China.  On its anticipated track Typhoon Meranti is expected to move northwest over Fujian province and then turn north toward Nanchang.

Typhoon Meranti is capable of causing significant wind damage over eastern China.  In addtion strong winds will create a significant storm surge along the coast near Xiamen.  Heavy rain will spread inland over Fujian province and the rain could create the potential for flooding over parts of eastern China.

Extremely Powerful Typhoon Meranti Nearing Southern Taiwan

The center of extremely powerful Typhoon Meranti moved closer to the southern end of Taiwan during the past few hours.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Meranti was located at latitude 21.1°N and longitude 121.3°E which put it about 65 miles (105 km) south-southeast of Hengchun, Taiwan.  Meranti was moving toward the west-northwest at 11 m.p.h. (18 km/h).  The maximum sustained wind speed was 190 m.p.h. (305 km/h) and there were wind gusts to 230 m.p.h. (370 km/h).  The minimum surface pressure was 887 mb.

Typhoon Meranti is large and powerful.  The Hurricane Intensity Index (HII) is 46.1.  The Hurricane Size Index (HSI) is 27.9 and the Hurricane Wind Intensity Size Index (HWISI) is 74.0.  As a source of comparison, when Hurriane Katrina was at its peak intensity as a Category 5 hurricane over the Gulf of Mexico in 2005, its HII was 38.6, its HSI was 33.7, and its HWISI was 72.3.  Typhoon Meranti is stronger than Hurricane Katrina was, but Meranti is a little smaller than Katrina was in 2005.  The indices suggest that Typhoon Meranti is capable of causing widespread catastrophic damage.

The circulation of Typhoon Meranti is symmetrical and very well organized.  It possess a tight core consisting of a small inner eye surrounded by a ring of very tall thunderstorms.  A second, larger outer eyewall completely surrounds the inner eye.  The strongest winds are occurring in the inner eyewall near the center of circulation.  Winds to typhoon force are also occurring in the outer eyewall and extend out at least 80 miles (130 km) from the center of circulation.  Additional bands of strong thunderstorms are rotating around the outer eyewall.  Typhoon Meranti is generating strong upper level divergence which is pumping out large quantities of mass and is allowing the surface pressure to be so low.

Typhoon Meranti is probably at its peak intensity.  It is still moving over water where the Sea Surface Temperature is near 31°C.  However, the northwestern edge of the outer eyewall appears to be moving over the southern end of Taiwan.  As more of the circulation moves over Taiwan, there will be some disruption of the airflow.  The center of Typhoon Meranti could move very close to the southern tip of Taiwan.  If the center of Meranti moves over southern Taiwan, then the typhoon will weaken more quickly.  It currently appears that the center of Typhoon Meranti could move just south of the southern tip of Taiwan, and on that track the typhoon would not weaken as quickly.  When Typhoon Meranti moves west of Taiwan, it will move over slightly cooler SSTs before it reaches China.  Meranti will weaken more before it reaches China, but it will still be a significant typhoon when it makes landfall there.

The center of Typhoon Meranti is wobbling a little as the inner eye rotates around inside the outer eyewall.  If one averages the wobbles, then then core of Meranti is moving on a general west-northwesterly track.  On its anticipated track, the center of Typhoon Meranti will pass very near the southern end of Taiwan during the next few hours.  It could turn slightly toward the northwest as it moves west of Taiwan.  Typhoon Meranti could make a landfall on the coast of China between Xiamen and Shantou in about 24 hours.

Typhoon Meranti is an extremely dangerous storm.  It is capable of causing widespread catastrophic wind damage.  In addition, its intensity and size will produce very heavy rainfall, especially on the eastern slopes of the mountains on Taiwan.  Flash flooding is likely.  Typhoon Meranti will also produce heavy rain over eastern China and additional flooding is likely in that region.  Typhoon Meranti will also cause a significant storm surge in low lying coastal areas.

Typhoon Meranti Becomes Equivalent of Cat. 5 Hurricane and Threatens Taiwan

Typhoon Meranti rapidly intensified into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale as it moved on a course that threatens Taiwan.  At 11:00 a.m. EDT on Monday the center of Typhoon Meranti was located at latitude 19.2°N and longitude 127.6°E which put it about 495 miles (800 km) southeast of Taiwan.  Meranti was moving toward the west-northwest at 14 m.p.h. (23 km/h).  The maximum sustained wind speed was 180 m.p.h. (290 km/h) and there were wind gusts to 220 m.p.h. (355 km/h).  The minimum surface pressure.

Meranti is a large dangerous typhoon.  The Hurricane Intensity Index (HII) is 42.2.  The Hurricane Size Index (HSI) is 25.5 and the Hurricane Wind Intensity Size Index (HWISI) is 67.7.  Those indices suggest that Typhoon Meranti is capable of causing widespread catastrophic damage.

The structure of Typhoon Meranti is very well organized.  A well formed circular eye is surrounded by a ring of very tall thunderstorms.  Additional strong spiral bands of thunderstorms are rotating around the core of the circulation.  Typhoon Meranti is generating strong upper level divergence which is pumping out mass in all directions.

Typhoon Meranti is moving through an environment that will allow it to maintain much of its intensity until it reaches Taiwan.  It is moving over water where the Sea Surface Temperature is near 31°C.  The upper level winds are weak and there is not much vertical wind shear.  If a rainband wraps around the existing eye, then an eyewall replacement cycle could temporarily weaken Typhoon Meranti.

A subtropical ridge is steering Typhoon Meranti toward the west-northwest and that general motion is expected to continue for several more days.  On its anticipated track Typhoon Meranti will be very near the southern tip of Taiwan in about 36 hours.  After it moves past Taiwan it is forecast to move into eastern China.

Meranti is an extremely dangerous typhoon.  It is capable of causing widespread catastrophic wind damage.  In addition it will produce very heavy rain and flooding is a serious concern.

Typhoon Meranti Strengthens Quickly Into the Equivalent of a Major Hurricane

Typhoon Meranti intensified rapidly on Sunday into the equivalent of a major hurricane.  At 11:00 p.m. EDT on Sunday the center of Typhoon Meranti was located at latitude 18.1°N and longitude 129.7°E which put it about 650 miles (1050 km) east-southeast of Taiwan.  Meranti was moving toward the west-northwest at 17 m.p.h. (27 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 948 mb.

Typhoon Meranti intensified very rapidly on Sunday.  A small, well formed eye developed at the center of Meranti.  A ring of strong thunderstorms surrounds the eye and additional bands of thunderstorms are spiraling around the core of the circulation.  The circulation is very symmetrical.  Thunderstorms in the core of Typhoon Meranti are generating strong upper level divergence which is pumping out large amounts of mass in all directions.  Meranti is a very well organized typhoon.

Typhoon Meranti is moving through a very favorable environment. It is moving over water where the Sea Surface Temperature is near 31°C.  The upper level winds are weak and there is little vertical wind shear.  Meranti will continue to intensify and it could become a Super Typhoon.  If an eyewall replacement cycle occurs, there could be fluctuations in the intensity of Meranti.

A subtropical ridge is steering Typhoon Meranti toward the west-northwest and that general motion is expected to continue for another couple of days.  On its anticipated track Typhoon Meranti will be near northern Luzon, Taiwan and the southern Ryukyu Islands in about 48 hours.  Meranti will be a dangerous typhoon at that time.  It will be capable of significant wind damage.  It will also cause very heavy rain and create the potential for significant flooding.

Tropical Storm Meranti Forms West of Guam

A center of circulation developed within an area of thunderstorms west of Guam on Saturday and the system was designated as Tropical Storm Meranti.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Meranti was located at latitude 16.0°N and longitude 135.8°E which put it about 1070 miles (1725 km) east-southeast of Taiwan.  Meranti was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 991 mb.

The circulation of Tropical Storm Meranti is still organizing and the distribution of thunderstorms is asymmetrical.  Most of the thunderstorms are occurring east of the center of circulation.  There is a cluster of the thunderstorms just to the east of the center.  There are also two well formed rainbands east of the core of Tropical Storm Meranti.  Additional spiral bands are located in all parts of the tropical storm.  The thunderstorms near the center are generating upper level divergence which is pumping out mass in all directions.

Tropical Storm Meranti is moving through an environment which is favorable for further intensification.  It is moving over water where the Sea Surface Temperature is near 31°C.  An upper level ridge located to the northwest of Meranti is producing northeasterly winds which are blowing across the western portion of the tropical storm.  The upper level winds are weaker over the eastern half of the circulation and the vertical wind shear is only slowing the intensification.  Although there may be some drier air in the western half of the circulation, Tropical Storm Meranti could intensify into a typhoon on Sunday.  Meranti could become a strong typhoon in two or three days.

A subtropical ridge north of Tropical Storm Meranti is steering it toward the west.  The subtropical ridge is forecast to steer Meranti in a general west-northwesterly direction during the next two or three days.  On its anticipated track Tropical Storm Meranti is expected to approach the area of northern Luzon, Taiwan and the southern Ryukyu Islands in about three days.  It could be a strong typhoon at that time.