Tag Archives: Ishigaki

Tropical Storms Sinlaku & Hagupit Form over West Pacific

Tropical Storms Sinlaku and Hagupit formed over the Western North Pacific Ocean on Saturday.  At 11:00 a.m. EDT on Saturday the center of Tropical Storm Sinlaku was located at latitude 19.4°N and longitude 107.1°E which put it about 90 miles (145 km) southeast of Nam Dinh, Vietnam.  Sinlaku was moving toward the northwest at 12 m.p.h. (19 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 993 mb.

The circulation around a low pressure system near Vietnam exhibited greater organization on Saturday and the Japan Meteorological Agency designated the system as Tropical Storm Sinlaku.  Bands of showers and thunderstorms were revolving around the center of Sinlaku.  There were more thunderstorms in the bands on the western side of the circulation.  Winds to tropical storm force extended out 110 miles (185 km) from the center of circulation.

Tropical Storm Sinlaku has about 12 hours to strengthen before it makes landfall in northern Vietnam.  Sinlaku will move over water where the Sea Surface Temperature is near 30°.  It will move under the southeast part of an upper level ridge over Asia.  The ridge will produce easterly winds which will blow toward the top of Sinlaku.  Those winds will cause moderate vertical wind shear and the shear will limit intensification.  Tropical Storm Sinlaku will bring gusty winds and rain to northern Vietnam on Sunday.

The circulation around a second low pressure system east of Taiwan also exhibited more organization on Saturday and the Japan Meteorological Agency designated that system as Tropical Storm Hagupit.  At 11:00 a.m. EDT on Saturday the center of Tropical Storm Hagupit was located at latitude 21.8°N and longitude 126.5°W which put it about 220 miles (350 km) southeast of Ishigaki, Japan.  Hagupit was moving toward the northwest at 13 m.p.h. (20 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 1003 mb.

The circulation around Tropical Storm Hagupit was still organizing on Saturday.  Thunderstorms were developing in bands in the eastern half of Hagupit.  Bands in the western side of the circulation consisted primarily of showers and lower clouds.  Storms near the center of Hagupit were generating upper level divergence which was pumping mass away to the east of the tropical storm.

Tropical Storm Hagupit will move through an environment favorable for intensification.  Hagupit will move over water where the Sea Surface Temperature is near 30°C.  Hagupit will move into a region where the upper level winds are weaker and there will not be a lot of vertical wind shear.  Tropical Storm Hagupit is likely to intensify during the next 24 to 36 hours.

Tropical Storm Hagupit will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high will steer Hagupit toward the northwest during the next several days.  On its anticipated track the center of Tropical Storm Hagupit will pass near Ishigaki, Japan in about 24 hours.  Hagupit will approach the coast of China south of Shanghai in about 48 hours.

Tropical Storm Mitag Forms Southeast of Ryukyu Islands

Tropical Storm Mitag formed southeast of the Ryukyu Islands on Friday.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Mitag was located at latitude 16.4°N and longitude 131.5°E which put it about 730 miles (1180 km) southeast of Ishigaki, Japan.  Mitag was movign toward the west-northwest at 27 m.p.h. (44 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 994 mb.

More thunderstorms developed near the center of a low pressure system southeast of the Ryukyu Islands on Friday and the Japan Meteorological Agency designated the system as Tropical Storm Mitag.  The distribution of thunderstorms around Tropical Storm Mitag was asymmetrical.  A few thunderstorms developed near the center of circulation, but most of the thunderstorms were forming in bands in the southern half of the circulation.  Bands in the northern half of Mitag consisted primarily of showers and lower clouds.  Tropical Storm Mitag was moving around the southwestern portion of an upper level ridge over the Western North Pacific Ocean.  The ridge was producing northeasterly winds which were blowing toward the top of Mitag.  Those winds were causing moderate vertical wind shear and they were contributing to the asymmetrical distribution of thunderstorms.

Tropical Storm Mitag will move through an environment somewhat favorable for intensification during the next two days.  Mitag will move over water where the Sea Surface Temperature is near 29°C.  Mitag will move around the western end of the upper level ridge where the winds are weaker.  The wind shear is likely to decrease and Tropical Storm Mitag is forecast to strengthen into a typhoon during the weekend.

The ridge over the Western North Pacific Ocean will steer Tropical Storm Mitag toward the northwest during the next 24 to 36 hours.  Mitag will move more toward the north when it moves around the west end of the ridge in about 48 hours.  On its anticipated track Tropcial Storm Mitag could reach the southern Ryukyu Islands in about 48 hours.  Mitag could be a typhoon at that time.

Tropical Storm Tapah Develops East of Taiwan

Tropical Storm Tapah developed east of Taiwan on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Tapah was located at latitude 23.3°N and longitude 126.5°E which put it about 150 miles (245 km) east-southeast of Ishigaki, Japan.  Tapah was moving toward the west at 7 m.p.h. (11 km/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 965 mb.

A distinct low level center of circulation formed on the northern side of an area of thunderstorms east of Taiwan on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Tapah.  The distribution of thunderstorms around Tapah was asymmetrical.  Most of the thunderstorms  were occurring in bands in the southern half of the circulation.  Bands in the northern half of the tropical storm consisted primarily of showers and lower clouds.  Storm on the southern side of the center began to generate upper level divergence which pumped mass away from the tropical storm.  The circulation around Tropical Storm Tapah was very large.  Winds to tropical storm force extended out about 250 miles (400 km) from the center of circulation.

Tropical Storm Tapah will move through an environment favorable for intensification during the next several days.  Tapah will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Some drier air north of Tropical Storm Tapah could inhibit the development of bands of thunderstorms on the northern side of the circulation.  Tropical Storm Tapah is likely to intensify and it could strengthen into a typhoon during the weekend.

Tropical Storm Tapah will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Tapah more toward the northwest on Friday.  Tapah will move more toward the north when it rounds the western end of the ridge.  On its anticipated track Tropical Storm Tapah could move over the southern Ryukyu Islands in about 12 hours.  The center of Tapah could pass west of Okinawa in about 24 hours.

Lingling Strengthens to Typhoon South of Ryukyu Islands

Former Tropical Storm Lingling strengthened to a typhoon south of the Ryukyu Islands on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Typhoon Lingling was located at latitude 21.7°N and longitude 124.3°E which put it about 180 miles (295 km) south of Ishigaki, Japan.  Lingling was moving toward the north at 8 m.p.h. (13 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 979 mb.

Typhoon Lingling exhibited much greater organization on Tuesday.  A circular eye with a diameter of 30 miles (50 km) developed at the center of circulation.  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 Lingling.  The strongest rainbands were occurring in the southeastern half of the circulation.  Storms near the core of Lingling were generating upper level divergence which was pumping mass away from the typhoon.  Winds to typhoon force extended out about 30 miles from the center of circulation.  Winds to tropical storm force extended out about 140 miles (220 km) from the center.

Typhoon Lingling will move through an environment favorable for intensification during the next 24 to 48 hours.  Lingling will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Lingling is likely to continue to intensify and it could strengthen into the equivalent of a major hurricane in a couple of days.

Typhoon Lingling is moving around the western end of a large subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lingling toward the north during the next several days.  On its anticipated track Typhoon Lingling could reach the southern Ryukyu Islands within 24 hours.  Lingling will bring strong, gusty winds and heavy rain to those islands.  Typhoon Lingling could approach Kyushu and South Korea in about three days.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Kajiki was dropping heavy rain over parts of Vietnam and Laos.  At 11:00 a.m. EDT on Tuesday the center of Tropical Depression Kajiki was located at latitude 16.4°N and longitude 107.3°E which put it about 65 miles (105 km) west-northwest of Da Nang, Vietnam.  Kajiki was moving toward the west at 8 m.p.h. (13 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 998 mb.

Typhoons Lekima and Krosa Threaten Japanese Islands

Typhoons Lekima and Krosa threatened Japanese islands on Wednesday.  Typhoon Lekima posed a serious threat to the southern Ryukyu Islands and Typhoon Krosa was headed for Iwo To.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Lekima was located at latitude 22.4°N and longitude 126.0°E which put it about 190 miles (305 km) southeast of Ishigaki, Japan.  Lekmia was moving toward the northwest at 8 m.p.h. (13 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 925 mb.

Typhoon Lekima rapidly intensified into the equivalent of a major hurricane on Wednesday.  A small distinct eye was at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.

Typhoon Lekima had a large circulation.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 23.6.  The Hurricane Size Index (HSI) was 21.6 and the Hurricane Wind Intensity Size Index (HWISI) was 44.7.   Those indices indicated that Typhoon Lekima was capable of causing widespread major damage.

Typhoon Lekima will move through an environment favorable for intensification during the next 24 hours.  Lekima will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will not be a lot of vertical wind shear.  Typhoon Lekima could intensify further during the next day or so.  It is possible that a rainband could wrap around the existing eye and eyewall.  If a rainband wraps around the core of Lekima then an eyewall replacement cycle could cause weakening.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the northwest on Thursday.  On its anticipated track Typhoon Lekima will reach Ishigaki and the southern Ryukyu Islands in less than 24 hours.  Lekima will be capable of causing major damage to the southern Ryukyu Islands.  Typhoon Lekima will move more toward the north when it moves around the end of the subtropical ridge.  The center of Lekima could be northeast of Taiwan within 36 hours.  Typhoon Lekima could reach the east coast of China in less than three days.

At 5:00 p.m. EDT on Wednesday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 140.8°E which put it about 210 miles (340 km) south of Iwo To.  Krosa was moving toward the north-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 970 mb.

Former Tropical Storm Krosa strengthened into a typhoon on Wednesday.  The inner portion of a rainband wrapped around the center of circulation and an eye formed.  The inner part of the rainband closed around the eye and a circular ring of thunderstorms formed a closed eyewall.  The strongest winds were occurring in the eyewall.  Several bands of showers and thunderstorms were revolving around the core of Typhoon Krosa.  Storms near the center were pumping mass away to the east of the typhoon.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 225 miles (360 km) from the center.  The Hurricane Intensity Index for Typhoon Krosa was 11.5.  The Hurricane Size Index was 22.5 and the Hurricane Wind Intensity Size Index was 34.0.

Typhoon Krosa will move through an environment mostly favorable for intensification.  Krosa will move over water where the Sea Surface Temperature is near 29°C.  Upper level divergence from Typhoon Lekima which is to the west of Typhoon Krosa could cause some vertical wind shear.  The wind shear will not be great enough to prevent intensification, but it could slow the rate at which Typhoon Krosa strengthens.

Typhoon Krose will move into a region where the steering winds are weaker.  Typhoon Krosa is forecast to move slowly toward the north during the next two or three days.  On its anticipated track the center of Typhoon Krosa could be near Iwo To in about 48 hours.

Tropical Storm Danas Nears Southern Ryukyu Islands

Tropical Storm Danas moved near the southern Ryukyu Islands late on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Danas was located at latitude 23.9°N and longitude 124.1°E which put it about 30 miles (50 km) south of Ishigaki, Japan.  Danas was moving toward the north at 21 m.p.h. (34 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 990 mb.

The circulation around Tropical Storm Danas exhibited a little more organization on Wednesday.  More thunderstorms formed near the center of circulation and several bands of showers and thunderstorms formed in the eastern half of the circulation.  The bands north and west of the center consisted primarily of showers and lower clouds.  Storms near the center began to generate upper level divergence which pumped mass away to the northeast of the tropical storm.  Winds to tropical storm force extended out about 125 miles (200 km) from the center of circulation.

Tropical Storm Danas will move into an environment somewhat favorable for intensification.  Danas will move over water where the Sea Surface Temperature is near 30°C.  A small upper level low near Taiwan will produce southwesterly winds which blow toward the top of the circulation around Tropical Storm Danas.  Those winds were the reason why the stronger rainbands were in the eastern half of the circulation.  Those winds will cause moderate vertical wind shear, which will inhibit intensification.  However, the shear will have less of an effect since Danas will move in the same direction as the upper level winds.  Tropical Storm Danas is likely to intensify during the next 24 hours and there is a chance it could strengthen into a typhoon.

Tropical Storm Danas will move around the western end of a subtropical ridge over the western North Pacific Ocean.  The ridge will steer Danas toward the north-northeast.  On its anticipated track Tropical Storm Danas will move through the southern Ryukyu Islands during the next few hours.  Danas will bring gusty winds and locally heavy rain when it passes over those islands.  Tropical Storm Danas will move over the East China Sea toward southwestern Japan and South Korea during the next several days.

Typhoon Maria Nears Southern Ryukyu Islands

Typhoon Maria neared the southern Ryukyu Islands on Monday night.  At 11:00 p.m. EDT on Monday night the center of Typhoon Maria was located at latitude 24.3°N and longitude 126.4°E which put it about 130 miles (210 km) east of Ishigaki, Japan.  Maria was moving toward the west-northwest at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 949 mb.

Typhoon Maria weakened slowly on Monday, but it remained a powerful typhoon.  Maria moved over some slightly cooler water mixed to the surface by recent Typhoon Prapiroon when it passed near the Ryukyu Islands.  Maria was unable to extract enough energy from the upper ocean to maintain the intense wind speeds it produced during the weekend.  However, Typhoon Maria was still the equivalent of a major hurricane.  There was a circular eye with a diameter of 35 miles (55 km).  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of thunderstorms were revolving around the core of Typhoon Maria.   Storms in the core were generating strong upper level divergence which was pumping mass away from the center of circulation.

Winds to typhoon force extended out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extended out about 200 miles from the center.  The Hurricane Intensity Index (HII) for Typhoon Maria was 23.6.  The Hurricane Size Index (HSI) was 23.8 and the Hurricane Wind Intensity Size Index (HWISI) was 47.4.  Those indices indicated that Typhoon Maria was capable of causing widespread major damage.

Typhoon Maria will move through an environment capable of sustaining a strong typhoon on Tuesday.  Maria will move west of the cooler water mixed to the surface by previous Typhoon Prapiroon and it will move over water where the Sea Surface Temperature is near 29°C.  Typhoon Maria will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Maria could weaken slowly on Tuesday if it is unable to extract enough energy from the upper ocean to sustain its circulation.  It could strengthen a little when it moves over slightly warmer water if it has time to extract more energy from the ocean.

Typhoon Maria was moving south of a subtropical ridge over the Western North Pacific Ocean.  The ridge was steering Maria toward the west-northwest and that general motion is expected to continue during the 36 hours.  On its anticipated track Typhoon Maria will reach the southern Ryukyu Islands in six to twelve hours.  Maria will bring destructive winds, heavy rain and a storm surge.  It will be capable of causing major damage to Miyako Jima, Ishigaki Jima, Iriomote Jima and the other islands in the southern Ryukyus.  The strongest part of Typhoon Maria will pass south of Okinawa, which could experience rainbands in the outer portion of the circulation.  Typhoon Maria will pass near northern Taiwan in about 18 hours.  It will bring strong winds and locally heavy rain to that area and flash floods could occur.  Maria could be near Fuding on the coast of China in about 24 hours.