Tag Archives: Ishigakijima

Tropical Storm Prapiroon Brings Wind and Rain to Hainan

Tropical Storm Prapiroon brought wind and rain to Hainan on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Prapiroon was located at latitude 19.1°N and longitude 109.9°E which put the center about 65 miles (105 km) south-southwest of Haikou, China.  Prapiroon was moving toward the northwest at 13 m.p.h. (21 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 992 mb.

Tropical Storm Prapiroon intensified on Sunday before the center moved over Hainan.  Microwave satellite images indicated that an eye was in the process of forming at the center of Prapiroon’s circulation as the tropical storm made landfall in Hainan.  The formative 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 center of Tropical Storm Prapiroon.

Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Storm Prapiroon.

The center of Tropical Storm Prapiroon made landfall on the south coast of Hainan near Lingshui.  The core of Prapiroon’s circulation moved across the center of Hainan.  Storms near the center of Tropical Storm Prapiroon brought heavy rain and strong winds to much of Hainan.  Bands in the northern part of Hainan’s circulation were also bringing gusty winds and heavy rain to parts of southern China.

Tropical Storm Prapiroon will move around the southern side of a high pressure system over southern China.  The high pressure system will steer Prapiroon toward the northwest during the next 24 hours.  On its anticipated track Tropical Storm Prapiroon will move over the Gulf of Tonkin on Monday.  The center of Prapiroon’s circulation could approach the southern coast of China in 24 hours.

Tropical Storm Prapiroon will continue to cause strong winds and locally heavy rain in Hainan during the next few hours.  Heavy rain could cause flash floods in some locations.  Prapiroon will also bring gusty winds and heavy rain to parts of southern China and northeastern Vietnam.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Gaemi strengthened east of Luzon.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Gaemi was located at latitude 17.2°N and longitude 125.7°E which put the center about 525 miles (845 km) south of Ishigakijima, Japan.  Gaemi was moving toward the north-northwest at 3 m.p.h. (5 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 992 mb.

Tropical Storm Prapiroon Forms Over South China Sea

Tropical Storm Prapiroon formed over the South China Sea on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Prapiroon was located at latitude 16.3°N and longitude 111.2°E which put the center about 260 miles (460 km) south-southeast of Haikou, China.  Prapiroon was moving toward the west at 5 m.p.h. (8 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 998 mb.

Former Tropical Depression 04W strengthened on Saturday night and the Japan Meteorological Agency designated the system as Tropical Storm Prapiroon.  The circulation around Tropical Storm Prapiroon was exhibiting a little more organization.  There were not a lot of thunderstorms near the center of Prapiroon’s circulation.  Thunderstorms were occurring in bands revolving around the center of Tropical Storm Prapiroon.

Although the circulation around Tropical Storm Prapiroon was large, the area of stronger winds was relatively small.  Winds to tropical storm force extended out 60 miles (95 km) from the center of Prapiroon’s circulation.

Tropical Storm Prapiroon will move through an environment somewhat favorable for intensification during the next 24 hours.  Prapiroon will move over water where the Sea Surface Temperatures are near 30°C.   It will move under the southeastern part of an upper level ridge over China.  The upper level ridge will produce northeasterly winds that will blow toward the top of Prapiroon’s circulation.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification but the shear may not be strong enough to prevent some strengthening.  Tropical Storm Prapiroon could intensify a little during the next 24 hours.

Tropical Storm Prapiroon will move around the southern part of a high pressure system over eastern China.  The high pressure system will steer Prapiroon toward the northeast during the next 24 hours.  On its anticipated track Tropical Storm Prapiroon will move toward Hainan.

Tropical Storm Prapiroon will bring gusty winds and heavy rain to Hainan during the next 24 hours.  Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Gaemi strengthened gradually east of the Philippines.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Gaemi was located at latitude 17.0°N and longitude 125.5°E which put the center about 485 miles (780 km) south of Ishigakijima, Japan.  Gaemi was moving toward the west-northwest at 9 m.p.h. (15 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.

Tropical Storm Gaemi Forms East of the Philippines

Tropical Storm Gaemi formed over the Western North Pacific Ocean east of the Philippines early on Saturday.   At 5:00 a.m. EDT on Saturday the center of Tropical Storm Gaemi was located at latitude 16.1°N and longitude 128.2°E which put the center about 520 miles (840 km) south-southeast of Ishigakijima, Japan.  Gaemi 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 1002 mb.

A low pressure system over the Western North Pacific Ocean east of the Philippines strengthened early on Saturday and the Japan Meteorological Agency designated the system as Tropical Storm Gaemi.  The circulation around Tropical Storm Gaemi was starting to exhibit more organization.  More thunderstorms were forming near the center of Gaemi’s circulation.  Thunderstorms were also developing in bands revolving around the center of Tropical Storm Gaemi.  Storms near the center of Gaemi started to generate upper level divergence that pumped mass away from the tropical storm.

Tropical Storm Gaemi will move through an environment favorable for intensification during the next 24 hours.  Gaemi will move over water where the Sea Surface Temperatures are near 30°C.   It will move under the western part of an upper level ridge over the Western North Pacific Ocean.  The upper level ridge will produce southeasterly winds that will blow toward the top of Gaemi’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Gaemi is likely to intensify gradually during the next 24 hours.  Gaemi could strengthen to a typhoon by early next week.

Tropical Storm Gaemi will move around the western part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Gaemi toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Gaemi will move toward the southern Ryukyu Islands.  Gaemi could be a typhoon when it approaches the southern Ryukyu Islands early next week.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 04W formed over the South China Sea.  At 5:00 a.m. EDT on Saturday the center of Tropical Depression 04W was located at latitude 16.1°N and longitude 113.8°E which put the center about 360 miles (580 km) southeast of Haikou, China.   The tropical depression was moving toward the northwest at 7 m.p.h. (11 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 999 mb.

Typhoon Mawar Moves South of Ryukyu Islands

Typhoon Mawar moved south of the Ryukyu Islands on Sunday morning. At 5:00 a.m. EDT on Sunday the center of Typhoon Mawar was located at latitude 17.7°N and longitude 125.7°E which put it about 505 miles (815 km) southeast of Ishigakijima, Japan. Mawar was moving toward the west-northwest at 11 m.p.h. (17 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 951 mb.

Typhoon Mawar continued to weaken gradually on Sunday morning as it moved over the Western North Pacific Ocean south of the Ryukyu Islands. A circular eye with a diameter of 20 miles (32 km) was present at the center of Mawar’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Numerous bands of showers and thunderstorms were revolving around the center of Typhoon Mawar. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm in all directions. The upper level divergence was still not removing as much mass as was converging in the lower levels of Mawar’s circulation which caused the surface pressure to continue to increase slowly.

Typhoon Mawar continued to be a large typhoon even though it was gradually weakening. Winds to typhoon force extended out 80 miles (130 km) from the center of Mawar’s circulation. Winds to tropical storm force extended out 250 miles (400 km) from the center of Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 22.1. The Hurricane Size Index (HSI) was 26.6 and the Hurricane Wind Intensity Size Index (HWISI) was 48.7. Typhoon Mawar was similar in size and intensity to Hurricane Jeanne when Jeanne hit South Florida in 2004.

Typhoon Mawar will move through an environment favorable for a strong typhoon during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the the axis of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Although the environment is favorable, Typhoon Mawar will continue to weaken gradually as long as the upper level divergence is removing less mass than is converging in the lower levels. Typhoon Mawar is forecast to continue to weaken during the next 24 hours.

Typhoon Mawar will move around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the west-northwest during the next 24 hours. Typhoon Mawar will move toward the north when it reaches the western end of the high pressure system early next week. On its anticipated track, Typhoon Mawar will move toward the southern Ryukyu Islands next week.

Typhoon Mawar Weakens a Little

Typhoon Mawar weakened a little on Saturday as it moved over the Western North Pacific Ocean south of the Ryukyu Islands. At 11:00 a.m. EDT on Saturday the center of Typhoon Mawar was located at latitude 16.9°N and longitude 130.4°E which put it about 650 miles (1050 km) southeast of Ishigakijima, Japan. Mawar was moving toward the west-northwest at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h). The minimum surface pressure was 926 mb.

Typhoon Mawar weakened a little after it went through another eyewall replacement cycle. The previous inner eye and eyewall dissipated. However, a circular eye with a diameter of 30 miles (50 km) was present at the center of Mawar’s circulation. The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms. Numerous bands of showers and thunderstorms were revolving around the center of Typhoon Mawar. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm in all directions. The upper level divergence was not able to remove as much mass as was converging in the lower levels of Mawar’s circulation which caused the surface pressure to increase slowly.

The recent eyewall replacement cycle caused the size of the circulation around Typhoon Mawar to remain large. Winds to typhoon force extended out 80 miles (130 km) from the center of Mawar’s circulation. Winds to tropical storm force extended out 275 miles (445 km) from the center of Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 31.6. The Hurricane Size Index (HSI) was 30.0 and the Hurricane Wind Intensity Size Index (HWISI) was 61.6. Typhoon Mawar was similar in size and intensity to Hurricane Wilma when Wilma was over the Northwest Caribbean Sea in 2005.

Typhoon Mawar will move through an environment favorable for a powerful typhoon during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the the axis of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Although the environment is favorable, the recent eyewall replacement cycle partially disrupted the inner core of Typhoon Mawar. Since the upper level divergence is removing less mass than is converging in the lower levels, the surface pressure is likely to increase slowly. If the surface pressure continues to increase, Typhoon Mawar will weaken gradually during the next 24 hours.

Typhoon Mawar will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the west-northwest during the next 24 hours. On its anticipated track, Typhoon Mawar could move south of Ishigakijima, Japan in 48 hours.

Typhoon Mawar Moves Southeast of Ryukyu Islands

Typhoon Mawar moved southeast of the Ryukyu Islands on Friday morning. At 11:00 a.m. EDT on Friday the center of Typhoon Mawar was located at latitude 15.8°N and longitude 135.8°E which put it about 930 miles (1500 km) southeast of Okinawa. Mawar was moving toward the west-northwest at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 165 m.p.h. (270 km/h) and there were wind gusts to 200 m.p.h. (320 km/h). The minimum surface pressure was 910 mb.

Concentric eyewalls formed in the core of Typhoon Mawar on Friday morning and another eyewall replacement cycle was underway. The inner eye had a diameter of 30 miles (50 km). The inner eye was surrounded by a larger, outer eyewall. Bands of showers and thunderstorms were revolving around the concentric eyewalls. Storms near the core of Mawar’s circulation generated strong upper level divergence that pumped mass away from the tropical storm in all directions. The removal of large quantities of mass allowed the surface pressure to remain very low.

The formation of concentric eyewalls caused the size of the circulation around Typhoon Mawar to increase again. Winds to typhoon force extended out 115 miles (185 km) from the center of Mawar’s. Winds to tropical storm force extended out 215 miles (345 km) from the center of Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 36.8. The Hurricane Size Index (HSI) was 33.5 and the Hurricane Wind Intensity Size Index (HWISI) was 70.3. Typhoon Mawar was similar in size and intensity to Hurricane Katrina when Katrina was a Category 5 hurricane on the Saffir-Simpson Scale over the Gulf of Mexico in 2005.

Typhoon Mawar will move through an environment favorable for a powerful typhoon during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the the axis of an upper level ridge over the Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Although the environment is favorable, Typhoon Mawar is likely to weaken while the eyewall replacement cycle occurs. The low level inflow will become more concentrated in the larger outer eyewall and the inner eyewall will weaken. Since the strongest winds are occurring in the inner eyewall, Mawar will weaken when the inner eyewall dissipates. Typhoon Mawar could start to strengthen again once the inner eyewall dissipates and the outer eyewall begins to contract around the center of circulation.

Typhoon Mawar will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the west-northwest during the next 24 hours. On its anticipated track, Typhoon Mawar could move southeast of Ishigakijima, Japan in three or four days.

Typhoon Muifa Brings Wind and Rain to Southern Ryukyu Islands

Typhoon Muifa brought wind and rain to the southern Ryukyu Islands on Monday. At 11:00 a.m. EDT on Monday the center of Typhoon Muifa was located at latitude 25.2°N and longitude 124.0°E which put it about 55 miles (90 km) north of Ishigaki, Japan. Muifa was moving toward the north-northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 967 mb.

Typhoon Muifa continued to bring wind and rain to the southern Ryukyu Islands on Monday. The center of Typhoon Muifa was moving slowly away from Ishigakijima. The strongest winds were measured in Ishigakijima after the eye passed over. A weather station on Ishigakijima measured a sustained wind speed of 68 m.p.h. (109 km/h). The same weather station measured a surface pressure of 968.3 mb when the eye of Typhoon Muifa passed over it. The weather station measured 11.71 inches (297.5 mm) of rain during the passage of Muifa. Bands in the eastern side of Muifa’s circulation also dropped heavy rain over Miyakojima.

The circulation around Typhoon Muifa remained well organized on Monday. A circular eye was present at the center of Muifa’s circulation. The 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 Typhoon Muifa. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

Winds to typhoon force extended out 45 miles (75 km) from the center of Typhoon Muifa. Winds to tropical storm force extended out 110 miles (175 km) from the center of Muifa. The Hurricane Intensity Index (HII) for Typhoon Muifa was 16.5. The Hurricane Size Index (HSI) was 15.4 and the Hurricane Wind Intensity Size Index (HWISI) was 31.9. Muifa was capable of causing regional serious damage.

Typhoon Muifa will move through an environment that will become unfavorable for intensification during the next 36 hours. Muifa will move over water where the Sea Surface Temperatures are near 30˚C. However, an upper level trough over China will produce southwesterly winds that will blow toward the top of Muifa’s circulation. Those winds will cause the vertical wind shear to increase during the next 36 hours. The increase in wind shear will cause Typhoon Muifa to start to weaken.

Typhoon Muifa will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Muifa slowly toward the north-northwest during the next 36 hours. The strong winds and locally heavy rain in the southern Ryukyu Islands will gradually diminish during the next 24 hours as Typhoon Muifa moves farther away. On its anticipated track Typhoon Muifa could approach the east coast of China south of Shanghai in 36 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Merbok continued to strengthen northwest of Wake Island. At 11:00 a.m. EDT on Monday the center of Tropical Storm Merbok was located at latitude 22.9°N and longitude 162.8°E which put it about 350 miles (565 km) northwest of Wake Island. Merbok was moving toward the northeast at 10 m.p.h. (16 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 994 mb.

Eye of Typhoon Muifa Passes over Ishigakijima

The eye of Typhoon Muifa passed directly over Ishigakijima on Sunday night. A weather station on Ishigakijima measured a surface pressure of 968.3 mb. At 11:00 p.m. EDT on Sunday the center of Typhoon Muifa was located at latitude 24.4°N and longitude 124.2°E which put it about 5 miles (10 km) east of Ishigaki, Japan. Muifa was moving toward the north-northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h). The minimum surface pressure was 967 mb.

Typhoon Muifa developed two concentric eyewalls and began an eyewall replacement cycle as it slowly approached Ishigakijima on Sunday. The inner end of rainband wrapped around the existing eye and eyewall and a larger outer eyewall surrounded them. Low level convergence became concentrated in the outer eyewall and the thunderstorms in the inner eyewall weakened. The remnants of the inner eyewall were visible on satellite images as a ring of showers and lower clouds. The outer eyewall had a diameter of 60 miles (95 km). The strongest winds were occurring in the outer eyewall. Bands of showers and thunderstorms were revolving around the core of Typhoon Muifa. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The eyewall replacement cycle caused Typhoon Muifa to weaken as it approached Ishigakijima. Winds to typhoon force extended out 35 miles (55 km) from the center of Typhoon Muifa. Winds to tropical storm force extended out 120 miles (195 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Muifa was 16.5. The Hurricane Size Index (HSI) was 13.9 and the Hurricane Wind Intensity Size Index (HWISI) was 30.4. Typhoon Muifa was capable causing regional serious damage.

Typhoon Muifa will move through an environment favorable for intensification during the next 24 hours. Muifa will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Muifa could intensify during the next 24 hours after the inner eyewall completely dissipates. Since Typhoon Muifa will move slowly, its winds could mix cooler water up to the surface of the ocean. Cooler water would limit potential intensification.

Typhoon Muifa will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Muifa slowly toward the north-northwest during the next 36 hours. Typhoon Muifa will continue to produce strong winds and locally heavy rain in the southern Ryukyu Islands during the next 24 hours. The strongest winds and heaviest rain are likely to affect Ishigakijima. Gusty winds and locally heavy rain could also affect Miyakojima. On its anticipated track Typhoon Muifa could approach the east coast of China near Shanghai in 60 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Merbok was slowly strengthening west-northwest of Wake Island. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Merbok was located at latitude 21.6°N and longitude 161.6°E which put it about 365 miles (595 km) west-northwest of Wake Island. Merbok was moving toward the east-northeast at 6 m.p.h. (10 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.

Powerful Typhoon Muifa Nears Ishigakijima

Powerful Typhoon Muifa neared Ishigakijima on Sunday morning. At 5:00 a.m. EDT on Sunday the center of Typhoon Muifa was located at latitude 23.1°N and longitude 124.2°E which put it about 85 miles (135 km) south of Ishigaki, Japan. Muifa was moving toward the north-northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 942 mb.

Typhoon Muifa was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale as it approached Ishigakijima from the south of Sunday. morning. A small circular eye was present at the center of Muifa’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. The inner end of a rainband wrapped part of the way around the eye and eyewall. A second concentric eyewall may be in the process of developing. Other bands of showers and thunderstorms were revolving around the core of Typhoon Muifa’s circulation. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

Winds to typhoon force extended out 40 miles (65 km) from the center of Typhoon Muifa. Winds to tropical storm force extended out 140 miles (225 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Muifa was 25.1. The Hurricane Size Index (HSI) was 15.1 and the Hurricane Wind Intensity Size Index (HWISI) was 40.2. Typhoon Muifa was capable causing regional severe damage.

Typhoon Muifa will move through an environment favorable for intensification during the next 24 hours. Muifa will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. However, two factors could prevent Typhoon Muifa from intensifying even though it will be in a favorable environment. First, if concentric eyewalls develop, then Muifa could weaken when an eyewall replacement cycle occurs. Second, Typhoon Muifa will move slowly and its winds could mix cooler water up to the surface of the ocean. Typhoon Muifa could intensify a little more during the next 12 hours, but it is likely to slowly weaken after that time.

Typhoon Muifa will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Muifa slowly toward the north-northwest during the next 36 hours. On its anticipated track, the center of Typhoon Muifa could be over Ishigakijima within 24 hours. Muifa is likely to be the equivalent of a major hurricane when it approaches the southern Ryukyu Islands. The center of Typhoon Muifa could pass directly over Ishigakijima. Ishigakijima is already reporting heavy rain. The wind speeds will increase steadily as the center of Muifa approaches. Typhoon Muifa is capable of causing severe damage. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 15W was spinning west-northwest of Wake Island. At 5:00 a.m. EDT on Sunday the center of Tropical Depression 15W was located at latitude 21.4°N and longitude 160.0°E which put it about 460 miles (745 km) west-northwest of Wake Island. The tropical depression was moving toward the east-northeast at 7 m.p.h. (11 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.

Typhoon Muifa Intensifies to Equivalent of a Major Hurricane

Typhoon Muifa intensified to the equivalent of a major hurricane south of the southern Ryukyu Islands on Saturday afternoon. At 5:00 p.m. EDT on Saturday the center of Typhoon Muifa was located at latitude 22.4°N and longitude 124.9°E which put it about 140 miles (230 km) south-southeast of Ishigaki, Japan. Muifa was moving toward the northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (230 km/h). The minimum surface pressure was 956 mb.

Typhoon Muifa intensified rapidly to the equivalent of a major hurricane over the Western North Pacific Ocean south of the southern Ryukyu Islands on Saturday. A circular eye with a diameter of 30 miles (50 km) was present at the center of Muifa’s 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 Muifa. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Muifa increased in size when it intensified. Winds to typhoon force extended out 35 miles (55 km/h) from the center of Muifa. Winds to tropical storm force extended out 130 miles (210 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Muifa was 20.6. The Hurricane Size Index (HSI) was 12.6 and the Hurricane Wind Intensity Size Index (HWISI) was 33.2. Typhoon Muifa was capable of causing regional major damage.

Typhoon Muifa will move through an environment favorable for intensification during the next 24 hours. Muifa will move over water where the Sea Surface Temperatures are near 30˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Muifa is likely to intensify during the next 24 hours.

Typhoon Muifa will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Muifa toward the north-northwest during the next 36 hours. On its anticipated track, the center of Typhoon Muifa could be near Ishigakijima within 36 hours. Muifa is likely to be the equivalent of a major hurricane when it approaches the southern Ryukyu Islands. The center of Typhoon Muifa could pass directly over Ishigakijima. Muifa will produce strong, damaging winds and locally heavy rain. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 15W formed west-northwest of Wake Island. At 5:00 p.m. EDT on Saturday the center of Tropical Depression 15W was located at latitude 21.0°N and longitude 160.0°E which put it about 455 miles (735 km) west-southwest of Wake Island. The tropical depression was moving toward the northeast at 7 m.p.h. (11 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.