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Typhoon Nyatoh Strengthens to Equivalent of a Major Hurricane

Typhoon Nyatoh strengthened to the equivalent of a major hurricane over the Western North Pacific Ocean southwest of Iwo To on Thursday. At 10:00 a.m. EST on Thursday the center of Typhoon Nyatoh was located at latitude 18.7°N and longitude 137.1°E which put it about 540 miles (875 km) southwest of Iwo To. Nyatoh was moving toward the northeast 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 955 mb.

Typhoon Nyatoh rapidly intensified to the equivalent of a major hurricane on Thursday. A circular eye with a diameter of 35 miles (55 km) formed at the center of Nyatoh. 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 Nyatoh. Storms near the core generated strong upper level divergence that pumped mass away to the northeast of the typhoon.

The circulation around Typhoon Nyatoh increased in size on Thursday. Winds to typhoon force extended out 65 miles (105 km) from the center of Nyatoh. Winds to tropical storm force extended out 220 miles (355 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Nyatoh was 20.6. The Hurricane Size Index (HSI) was 22.1 and the Hurricane Wind Intensity Size Index (HWISI) was 42.7.

Typhoon Nyatoh will move through an environment that will become unfavorable for intensification during the next 24 hours. Nyatoh will move over water where the Sea Surface Temperatures are near 28˚C. An upper level trough near Japan will produce southwesterly winds that will blow toward the top of Nyatoh’s circulation. Those winds will cause the vertical wind shear to increase during the next 24 hours. Clockwise flow around a surface high pressure system centered over eastern Asia will transport drier air toward the northwestern part of Nyatoh’s circulation. The drier air will begin to be pulled into the northwestern part of Typhoon Nyatoh’s circulation during the next 24 hours. The combination of more vertical wind shear and drier air will cause Typhoon Nyatoh to start to weaken.

The upper level trough near Japan will steer Typhoon Nyatoh toward the northeast during the next 24 hours. On its anticipated track Typhoon Nyatoh could approach Iwo To on Friday. Although Nyatoh will weaken, it will bring strong winds and locally heavy rain to Iwo To.

Nyatoh Strengthens to a Typhoon West of the Marianas

Former Tropical Storm Nyatoh strengthened to a typhoon west of the Marianas on Wednesday. At 10:00 a.m. EST on Wednesday the center of Typhoon Nyatoh was located at latitude 15.5°N and longitude 135.6°E which put it about 580 miles (935 km) west-northwest of Guam. Nyatoh was moving toward the north-northwest at 11 m.p.h. (17 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 981 mb.

Former Tropical Storm Nyatoh continued to strengthen over the Western North Pacific Ocean west of the Marianas on Wednesday. The inner end of a rainband wrapped around the center of Typhoon Nyatoh and microwaves satellite images indicated that an eye was forming. The developing eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Nyatoh. Storms near the core generated upper level divergence that pumped mass away from the typhoon. Winds to typhoon force extended out 35 miles (55 km) from the center of Nyatoh. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation.

Typhoon Nyatoh will move through an environment mostly favorable for intensification during the next 24 hours. Nyatoh will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western part of the axis of an upper level ridge centered near the Marianas. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Clockwise flow around a high pressure system centered over eastern Asia will transport drier air toward the northwestern part of Nyatoh’s circulation. The drier air is likely to remain northwest of Typhoon Nyatoh during the next 24 hours. Nyatoh could intensify more rapidly once the eye and eyewall become fully formed. Typhoon Nyatoh will continue to strengthen and it could intensify to the equivalent of a major hurricane during the next 24 hours. An upper level trough west of Japan will produce southwesterly winds that will begin to affect Nyatoh later this week. Those winds will create more vertical wind shear and the shear will cause Typhoon Nyatoh to weaken.

Typhoon Nyatoh will move around the western part of a high pressure system over the Western North Pacific Ocean during the next 24 hours. The high pressure system will steer Nyatoh toward the north during the next 24 hours. The upper level trough will steer Typhoon Nyatoh toward the northeast after Nyatoh moves around the western end of the high pressure system. On its anticipated track Tropical Storm Nyatoh will remain west of the Marianas during the next 24 hours. Nyatoh could approach Iwo To in 48 hours.

Tropical Storm Nyatoh Strengthens West of the Marianas

Tropical Storm Nyatoh strengthened over the Western North Pacific Ocean west of the Marianas on Tuesday. At 4:00 p.m. EST on Tuesday the center of Tropical Storm Nyatoh was located at latitude 13.4°N and longitude 136.7°E which put it about 510 miles (825 km) west of Guam. Nyatoh was moving toward the west-northwest at 7 m.p.h. (11 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.

Tropical Storm Nyatoh continued to strengthen west of the Marianas on Tuesday. The inner end of a rainband wrapped around the northern and western sides of the center of Nyatoh. Additional bands of showers and thunderstorms were revolving around the center of Tropical Storm Nyatoh. Storms near the center of circulation generated strong upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 130 miles (210 km) from the center of Nyatoh’s circulation.

Tropical Storm Nyatoh will move through an environment mostly favorable for intensification during the next 24 hours. Nyatoh will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of the axis of an upper level ridge centered east of the Marianas. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Clockwise flow around a high pressure system centered over eastern Asia could transport drier air toward the northwestern part of Nyatoh’s circulation. The drier air is likely to remain northwest of Tropical Storm Nyatoh during the next 24 hours. Nyatoh could intensify more rapidly once the inner end of the rainband wraps around the center of circulation and a core with an eye and an eyewall develops. Tropical Storm Nyatoh will continue to strengthen and it will intensify to a typhoon during the next 24 hours.

Tropical Storm Nyatoh will move around the western part of a high pressure system over the Western North Pacific Ocean during the next 24 hours. The high pressure system will steer Nyatoh toward the north during the next 24 hours. Nyatoh could move toward the northeast after it moves around the western end of the high pressure system. On its anticipated track Tropical Storm Nyatoh will remain west of the Marianas during the next 24 hours.

TD 27W Strengthens to Tropical Storm Nyatoh West of Guam

Former Tropical Depression 27W strengthened to Tropical Storm Nyatoh west of Guam on Monday night. At 10:00 p.m. EST on Monday the center of Tropical Storm Nyatoh was located at latitude 13.0°N and longitude 138.7°E which put it about 370 miles (600 km) west of Guam. Nyatoh 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 1000 mb.

The circulation around former Tropical Depression 27W continued to strengthen on Monday night and the Japan Meteorological Agency upgraded the system to Tropical Storm Nyatoh. More thunderstorms developed near the center of circulation and in the bands revolving around the center of Nyatoh. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 125 miles (200 km) from the center of Tropical Storm Nyatoh.

Tropical Storm Nyatoh will move through an environment mostly favorable for intensification during the next 36 hours. Nyatoh will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of the axis of an upper level ridge centered east of the Marianas. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Clockwise flow around a high pressure system centered over eastern Asia could transport drier air toward the northwestern part of Nyatoh’s circulation. The drier air is likely to remain northwest of the core of Tropical Storm Nyatoh during the next 36 hours. Tropical Storm Nyatoh will continue to strengthen and it could intensify to a typhoon during the next 36 hours.

Tropical Storm Nyatoh will move around the southwestern part of a high pressure system over the Western North Pacific Ocean during the next 36 hours. The high pressure system will steer the tropical depression toward the northwest during the next 36 hours. On its anticipated track Tropical Storm Nyatoh will move farther away from the Marianas and Yap.

Tropical Depression Forms Southwest of the Marianas

A tropical depression formed southwest of the Marianas on Monday morning. At 7:00 a.m. EST on Monday the center of Tropical Depression 27W was located at latitude 11.8°N and longitude 141.1°E which put it about 270 miles (435 km) west-southwest of Guam. The tropical depression was moving toward the west-northwest at 12 m.p.h. (19 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.

The circulation around a low pressure system west-southwest of Guam exhibited more organization on Monday morning and the Japan Meteorological Agency designated the system as a tropical depression. The circulation around Tropical Depression 27W was gradually becoming more organized. A distinct low level center of circulation was evident on conventional and microwave satellite images. More thunderstorms were beginning to develop near the center of circulation. Storms near the center began to generate upper level divergence that pumped mass away from the tropical depression. Additional thunderstorms were forming in bands revolving around the center of the depression.

Tropical Depression 27W will move through an environment favorable for intensification during the next 24 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the western part of the axis of an upper level ridge centered east of the Marianas. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Depression 27W will strengthen gradually and it is likely to intensify to a tropical storm during the next 24 hours.

Tropical Depression 27W will move around the southwestern part of a high pressure system over the Western North Pacific Ocean during the next 24 hours. The high pressure system will steer the tropical depression toward the west-northwest during the next day or so. On its anticipated track Tropical Depression 27W will move farther away from the Marianas. It will pass north of Yap.

Tropical Storm Fung-wong Nears Southern Ryukyu Islands

Tropical Storm Fung-wong neared the southern Ryukyu Islands on Thursday night.  At 10:00 p.m. EDT on Thursday the center of Tropical Storm Fung-wong was located at latitude 23.3°N and longitude 124.9°E which put it about 110 miles (175 km) south-southwest of Harari, Japan.  Fung-wong was moving toward the north-northeast at13 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 989 mb.

Tropical Storm Fung-wong was weakening gradually as it neared the southern Ryukyu Islands.  An upper level trough over east Asia was producing southwesterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear.  There was still a well defined low level center of circulation.  A broken ring of thunderstorms surrounded the center and the strongest winds were occurring near the center of Fung-wong.  Most of the stronger thunderstorms were occurring in bands north and east of the center of circulation.  Bands in the southern and western parts of the tropical storm consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 120 miles (195 km) from the center of circulation.

A high pressure system over the Western North Pacific Ocean and the trough over east Asia will interact to steer Tropical Storm Fung-wong toward the north-northeast during the next 24 to 36 hours.  On its anticipated track Fung-wong will move over the southern Ryukyu Islands during the next 24 hours.  The center of the tropical storm could pass close to Miyako Jima in about 12 hours.  Tropical Storm Fung-wong will continue to weaken gradually because of the moderate vertical wind shear.  Fung-wong will bring gusty winds and locally heavy rain to some of the southern Ryukyu Islands.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Kalmaegi was moving across the South China Sea toward Vietnam.  At 10:00 p.m. EST on Thursday the center of Tropical Depression Kalmaegi was located at latitude 11.5°N and longitude 114.5°E which put it about 550 miles (890 km) east of Ho Chi Minh City, Vietnam.  Kalmaegi was moving toward the west-southwest 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 1004 mb.  Tropical Depression Kalmaegi could drop locally heavy rain over parts of southern Vietnam during the weekend.

Tropical Storm Kalmaegi Brings Wind and Rain to Northern Luzon

Tropical Storm Kalmaegi brought wind and rain to northern Luzon on Tuesday night.  At 10:00 p.m. EST on Tuesday the center Tropical Storm Kalmaegi was located at latitude 17.0°N and longitude 121.2°W which put it about 70 miles (110 km) northeast of Baguio, Philippines.  Kalmaegi was moving toward the south-southwest at 15 m.p.h. (24 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.

Former Typhoon Kalmaegi weakened to a tropical storm before it made landfall on the north coast of Luzon near Aparri.  Kalmaegi was under the western end of an upper level ridge.  The ridge produced strong southerly winds which blew toward the top of the circulation.  Those winds caused moderate vertical wind shear which weakened thunderstorms in the southern half of the circulation.  Drier air from Asia was pulled into the western part of the tropical storm.  The stronger thunderstorms were occurring northeast of the center of circulation.  Winds to tropical storm force extended out 100 miles (160 km) from the center in most parts of Tropical Storm Kalmaegi.  A high pressure system over Asia was contributing to a bigger pressure gradient in the northwestern quadrant of Kalmaegi and winds to tropical storm force extended out 200 miles (320 km) in that area.

Tropical Storm Kalmaegi was dropping locally heavy rain over parts of northern Luzon.  The heavy rain was creating the potential for flash floods.  Kalmaegi will be steered toward the southwest by the high pressure system over Asia. On its anticipated track the center of Tropical Storm Kalmaegi will pass near Baguio.  Kalmaegi will continue to weaken as it moves over northern Luzon.  It will move over the South China Sea northwest of Manila.  Tropical Storm Kalmaegi will continue to drop heavy rain over parts of Luzon and the flash flood threat will continue for several more days.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Fung-wong developed east of Luzon on Tuesday night.  At 10:00 p.m. EST the center of Tropical Storm Fung-wong was located at latitude 16.3°N and longitude 127.8°E which put it about 425 miles (685 km) east-southeast of Aparri, Philippines.  Fung-wong was moving toward the northwest 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 1000 mb.  Tropical Storm Fung-wong is forecast to strengthen during the next 36 hours while it moves toward the Luzon Strait.

Tropical Storm Kalmaegi Almost a Typhoon Near Northern Luzon

Tropical Storm Kalmaegi was almost a typhoon as it neared northern Luzon on Sunday night.  At 10:00 p.m. EST on Sunday the center of Tropical Storm Kalmaegi was located at latitude 17.7°N and longitude 123.2°E which put it about 120 miles (195 km) east-southeast of Aparri, Philippines.  Kalmaegi was moving toward the northwest at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 984 mb.

Tropical Storm Kalmaegi was on the verge of strengthening into a typhoon on Sunday night.  The inner end of a band of showers and thunderstorms wrapped most of the way around the center of circulation and an eye appeared to be forming.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Kalmaegi.  Storms near the center were generating upper level divergence which was pumping mass away to the northeast of the tropical storm.  Winds to tropical storm force extended out 110 miles (175 km) from the center of circulation.

Tropical Storm Kalmaegi will move through an environment favorable for intensification for anther 12 to 24 hours.  Kalmaegi 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 blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Storm Kalmaegi is likely to strengthen into a typhoon on Monday.

A ridge of high pressure will steer Tropical Storm Kalmaegi toward the northwest during the next 12 to 24 hours.  On its anticipated track the center of Tropical Storm Kalmaegi will make a landfall on the north coast of Luzon near Aparri in about 24 hours.  Kalmaegi will weaken after the center moves over land.  When Tropical Storm Kalmaegi weakens a strong northeasterly flow in the lower levels will steer the tropical storm back toward the southwest.  Tropical Storm Kalmaegi will bring gusty winds and it will drop locally heavy rain over northern Luzon.  Heavy rain could cause flash floods in some locations.

Tropical Storm Kalmaegi Strengthens East of Luzon

Tropical Storm Kalmaegi strengthened east of Luzon on Saturday night.  At 10:00 p.m. EST on Saturday the center of Tropical Storm Kalmaegi was located at latitude 15.7°N and longitude 125.2°E which put it about 300 miles (185 km) east-southeast of Aparri, Philippines.  Kalmaegi was moving toward the west-northwest at 5 m.p.h. (8 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.

After meandering for days east of Luzon, Tropical Storm Kalmaegi began to strengthen on Saturday night.  Bands of showers and thunderstorms strengthened and wrapped around the eastern and northern sides of the center of circulation.   Storms near the center began to generate upper level divergence which pumped mass away to the northeast of the tropical storm.  Bands in the western half of the circulation still consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 120 miles (195 km) from the center.

Tropical Storm Kalmaegi will move through an environment favorable for intensification during the next 24 to 36 hours.  Kalmaegi will move over water where the Sea Surface Temperature is near 29°C.  It will move south of an upper level ridge over the Western North Pacific Ocean.  The ridge will produce easterly winds which will cause some vertical wind shear.  The shear will slow the rate of intensification, but it will not be strong enough to prevent intensification.  Tropical Storm Kalmaegi could strengthen into a typhoon during the next 36 hours.

The ridge over the Western Pacific Ocean will steer Tropical Storm Kalmaegi toward the northwest during the next 36 hours.  On its anticipated track Tropical Storm Kalmaegi could approach northern Luzon in about 36 hours.  Kalmaegi could be a typhoon by that time.

Elsewhere over the Western North Pacific Ocean, Typhoon Fengshen was speeding away from Iwo To.  At 10:00 p.m. EST on Saturday the center of Typhoon Fengshen was located at latitude 26.4°N and longitude 153.1°E which put it about 690 miles (1110 km) east-northeast of Iwo To.  Fengshen was moving toward the east at 31 m.p.h. (50 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 962 mb.

Typhoon Fengshen Strengthens into Equivalent of a Major Hurricane

Typhoon Fengshen strengthened into the equivalent of a major hurricane on Friday.  At 4:00 p.m. EST on Friday the center of Typhoon Fengshen was located at latitude 23.0°N and longitude 142.9°E which put it about 175 miles (285 km) south-southeast of Io To.  Fengshen was moving toward the north at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 949 mb.

Typhoon Fengshen strengthened quickly into the equivalent of a major hurricane on Friday.  An eye with a diameter of 25 miles (40 km) developed at the center of Fengshen.  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 Fengshen.  Storms near the core were generating strong upper level divergence which was pumping mass away to the northeast of the typhoon.

The circulation around Typhoon Fengshen increased in size on Friday.  Winds to typhoon force extended out 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out 140 miles (225) km from the center.  The Hurricane Intensity Index (HII) for Typhoon Fengshen was 23.6.  The Hurricane Size Index (HSI) was 11.2 and the Hurricane Wind Intensity Size Index (HWISI) was 34.8.

Typhoon Fengshen may have reached its peak intensity.  Fengshen will move over water where the Sea Surface Temperature is near 28°C.  So, there will be suffiicient energy in the upper levels of the Western Pacific to support intensification.  However, a large upper level trough southwest of Japan will move toward Fengshen.  The trough will produce strong southwesterly winds which will blow toward the top of the typhoon.  Those winds will cause moderate to strong vertical wind shear and the shear will cause Typhoon Fengshen to being to weaken.

A ridge of high pressure east of Typhoon Fengshen and the upper level trough southwest of Japan will interact to steer the typhoon toward the northeast during the weekend.  On its anticipated track the core of Typhoon Fengshen which contains the strongest winds will pass southeast of Iwo To.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Kalmaegi moved very slowly toward northern Luzon.  At 4:00 p.m. EST on Friday the center of Tropical Storm Kalmaegi was located at latitude 16.0°N and longitude 125.9°E which put it about 345 miles (555 km) southeast of Aparri, Philippines.  Kalmaegi was moving toward the west at 2 m.p.h. (3 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.