Tag Archives: Ryukyu Islands

Typhoon Doksuri Moves over Taiwan Strait

Typhoon Doksuri moved over the Taiwan Strait on Thursday morning. At 11:00 a.m. EDT on Thursday the center of Typhoon Doksuri was located at latitude 22.3°N and longitude 119.0°E which put it about 170 miles (275 km) south-southeast of Xiamen China. Doksuri was moving toward the north-northwest at 8 m.p.h. (13 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 943 mb.

Radar images from Taiwan’s Central Weather Bureau showed clearly that there were concentric eyewalls at the core of Typhoon Doksuri. A small circular eye with a diameter of 7 miles (11 km) was at the center of Doksuri’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. The inner eyewall was surrounded by a relatively clear area, sometimes called a moat. A much larger, outer eyewall with a diameter of 60 miles (95 km) surrounded the inner eyewall and the moat. Bands of showers and thunderstorms were revolving around the concentric eyewalls. Storms in the concentric eyewalls generated upper level divergence that pumped mass away from the typhoon.

Both the inner and outer eyewalls of Typhoon Doksuri were over the Taiwan Strait. Mountains in Taiwan were deflecting some of the wind circulating around the eastern side of Doksuri, and the core of circulation tightened up a little. Winds to typhoon force extended out 45 miles (75 km) from the center of Doksuri’s circulation. Winds to tropical storm force extended out 160 miles (260 km) from the center. The Hurricane Intensity Index (HII) for Typhoon Doksuri was 22.1. The Hurricane Size Index (HSI) was 17.1 and the Hurricane Wind Intensity Size Index (HWISI) was 39.2. Typhoon Doksuri was bigger and stronger than Hurricane Delta when Delta hit Louisiana in 2020. Doksuri was capable of causing regional severe damage.

Typhoon Doksuri will move through an environment very favorable for intensification during the next 12 hours. Doksuri will move over water where the Sea Surface Temperatures are near 31˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. However, the concentric eyewalls at the center of Typhoon Doksuri will inhibit intensification. Doksuri could weaken if the inner eye and eyewall dissipate. If the inner eye and eyewall remain intact, then Typhoon Doksuri could strengthen during the next 12 hours.

Typhoon Doksuri will move around the western side of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Doksuri toward the north-northwest during the next 24 hours. On its anticipated track, Typhoon Doksuri will approach the east coast of China near Xiamen in 24 hours. Doksuri will bring strong winds and heavy rain to Fujian. Heavy rain could cause flash floods in some locations. Typhoon Doksuri could also cause a storm surge of up to 13 feet (4 meters) along the coast of Fujian.

Bands in the eastern side of Typhoon Doksuri will continue to drop heavy rain on parts of Taiwan during the next 24 hours. The heaviest rain will fall initially on the eastern side of mountains where the winds around Doksuri will push air up the slopes. Heavy rain could fall on the western sides of mountains when Typhoon Doksuri moves farther north and the wind over Taiwan blows from the south. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, a new tropical depression formed east of the Philippines. At 11:00 a.m. EDT on Thursday the center of Tropical Depression 06W was located at latitude 12.7°N and longitude 137.5°E which put it about 170 miles (275 km) northwest of Yap. The tropical depression was moving toward the west-northwest at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1003 mb. Tropical Depression 06W is forecast to move toward the Ryukyu Islands and to strengthen to a typhoon.

Typhoon Mawar Moves South-southeast of Miyakojima

Typhoon Mawar move south-southeast of Miyakojima on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Typhoon Mawar was located at latitude 23.0°N and longitude 125.6°E which put it about 120 miles (195 km) south-southeast of Miyakojima, Japan. Mawar was moving toward the north-northeast at 5 m.p.h. (8 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.

Typhoon Mawar continued to weaken slowly as it moved closer to the southern Ryukyu Islands on Wednesday. The circulation around Mawar was pulling drier air from Asia into the western part of the typhoon. Bands in the western half of Typhoon Mawar consisted primarily of showers and lower clouds. Many of the thunderstorms in Mawar were occurring in bands in the eastern half of the typhoon. Storms in the eastern half of Mawar’s circulation generated upper level divergence that pumped mass away to the east of the typhoon. Winds to typhoon force extended out 60 miles (95 km) from the center of Mawar. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation.

Typhoon Mawar will move through an environment that will be less favorable for intensification during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 27˚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. The drier air in the western half of Mawar’s circulation air will inhibit the formation of thunderstorms in that part of the typhoon. In addition, since Typhoon Mawar is moving slowly, winds in the lower levels are likely to mix cooler water to the surface of the Pacific Ocean. The effects of the drier air and mixing of cooler water to the surface of the ocean are likely to cause Typhoon Mawar to weaken gradually during the next 24 hours.

Typhoon Mawar will move around the western part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the north-northeast during the next 24 hours. On its anticipated track, the center of Typhoon Mawar will pass a little to the east of Miyakojima in 12 hours. Mawar could approach Okinawa in 24 hours. Mawar is likely to be tropical storm when it reaches Okinawa.

Typhoon Mawar Slows South of the Ryukyu Islands

Typhoon Mawar slowed over the Western North Pacific Ocean south of the Ryukyu Islands on Tuesday. At 11:00 a.m. EDT on Tuesday the center of Typhoon Mawar was located at latitude 20.9°N and longitude 125.0°E which put it about 260 miles (420 km) south of Miyakojima, Japan. Mawar was moving toward the north at 3 m.p.h. (5 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 978 mb.

Typhoon Mawar weakened as it moved slowly toward the Ryukyu Islands on Tuesday. The circulation around Mawar appeared to pull drier air from Asia into the northwestern part of the typhoon. Thunderstorms in bands in the northwestern quadrant of Typhoon Mawar weakened on Tuesday. The northwestern part of the eyewall also weakened. Most of the remaining thunderstorms were occurring in the southern half of Typhoon Mawar. Storms near the center of Mawar’s circulation generated upper level divergence that pumped mass away from the typhoon. The divergence of mass in the upper levels was less than the convergence of mass in the lower levels of Typhoon Mawar and the surface pressure continued to increase.

Even though Typhoon Mawar was weaker, it continued to have a large circulation after several eyewall replacement cycles. Winds to typhoon force extended out 70 miles (110 km) from the center of Mawar. Winds to tropical storm force extended out 225 miles (360 km) from the center of circulation.

Typhoon Mawar will move through an environment that will become less favorable for intensification during the next 24 hours. Mawar will move over water where the Sea Surface Temperatures are near 28˚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. Drier air will persist northwest of Typhoon Mawar. The drier air will inhibit the formation of thunderstorms in the northern half of Mawar’s circulation. In addition, since Typhoon Mawar is moving slowly, winds in the lower levels are likely to mix cooler water to the surface of the Pacific Ocean. The effects of the drier air and mixing of cooler water to the surface of the ocean are likely to cause Typhoon Mawar to weaken gradually during the next 24 hours.

Typhoon Mawar will move around the western part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar slowly toward the north during the next 36 hours. On its anticipated track, the center of Typhoon Mawar will be near Miyakojima in 36 hours. Mawar could be near Okinawa in less than 72 hours.

Typhoon Mawar Moves Toward Southern Ryukyu Islands

Typhoon Mawar moved toward the southern Ryukyu Islands on Monday morning. At 11:00 a.m. EDT on Monday the center of Typhoon Mawar was located at latitude 19.8°N and longitude 125.5°E which put it about 330 miles (535 km) south of Miyakojima, Japan. Mawar was moving toward the north-northwest at 5 m.p.h. (8 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. (235 km/h). The minimum surface pressure was 956 mb.

Typhoon Mawar was in an equilibrium with its environment during much of the past 24 hours. The inner end of a rainband recently wrapped around the existing eye and eyewall and another pair of concentric eyewalls developed. The inner eye had a diameter of 30 miles (50 km). The inner eyewall was surrounded by a clear area, called a moat, and a much larger outer eyewall. Bands of showers and thunderstorms were revolving around the concentric eyewalls. The strongest rainbands were in the southern half of Mawar’s circulation. Storms near the concentric eyewalls generated upper level divergence that pumped mass away from the typhoon. The upper level divergence pumped away an amount of mass that was nearly equal to the mass converging in the lower levels of Mawar’s circulation. Since the upper level divergence was nearly equal to the lower level convergence, Typhoon Mawar maintained a nearly steady intensity during the past 24 hours.

The circulation around Typhoon Mawar continued to be large. Winds to typhoon force extended out 70 miles (110 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 20.6. The Hurricane Size Index (HSI) was 21.1 and the Hurricane Wind Intensity Size Index (HWISI) was 41.7. Typhoon Mawar was similar in intensity to Hurricane Rita when Rita hit Southwest Louisiana in 2005. Mawar was a little smaller than Rita was.

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, the formation of concentric eyewalls is likely to start an eyewall replacement cycle that will cause Typhoon Mawar to weaken gradually during the next 24 hours.

Typhoon Mawar will move around the western part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Mawar toward the north during the next 36 hours. The steering winds will weaken as Mawar moves around the western end of the high pressure system. On its anticipated track, Typhoon Mawar will move slowly toward the southern Ryukyu Islands during the next 36 hours.

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 Mawar Gets Bigger and Stronger

Powerful Typhoon Mawar continued to get bigger and stronger on Thursday as it moved west of the Marianas. At 11:00 p.m. EDT on Thursday the center of Typhoon Mawar was located at latitude 15.2°N and longitude 138.6°E which put it about 385 miles (625 km) west-northwest of Guam. Mawar was moving toward the west-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 185 m.p.h. (295 km/h) and there were wind gusts to 225 m.p.h. (360 km/h). The minimum surface pressure was 895 mb.

Typhoon Mawar continued to intensify on Thursday as it moved over the Western North Pacific Ocean west of the Marianas. A circular eye with a diameter of 26 miles (43 km) was present at the center of Mawar’s circulation. A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Mawar. 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 caused the surface pressure to continue to decrease.

The circulation around Typhoon was large. Winds to typhoon force extended out 65 miles (105 km) from the center of Typhoon Mawar. Winds to tropical storm force extended out 205 miles (335 km) from the center of Mawar. The Hurricane Intensity Index (HII) for Typhoon Mawar was 44.1. The Hurricane Size Index (HSI) was 22.5 and the Hurricane Wind Intensity Size Index (HWISI) was 66.6. Typhoon Mawar was as strong as Hurricane Dorian was when Dorian hit the Bahamas in 2019. Mawar was much larger than Dorian was.

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. Typhoon Mawar is likely to maintain much of its intensity during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then a new eyewall replacement cycle could cause Mawar to weaken temporarily.

Typhoon Mawar will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean. T he high pressure system will steer Mawar toward the west-northwest during the next 24 hours. On its anticipated track, Typhoon Mawar will continue to move farther away from the Marianas. Mawar could move south of the Ryukyu Islands by the end of the weekend.

Typhoon Mawar Strengthens to Equivalent of Cat. 5 Hurricane

Typhoon Mawar strengthened to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale over the Western North Pacific Ocean west of the Marianas on Thursday morning. At 5:00 a.m. EDT on Thursday the center of Typhoon Mawar was located at latitude 14.6°N and longitude 142.2°E which put it about 145 miles (230 km) west-northwest of Guam. Mawar was moving toward the west-northwest at 8 m.p.h. (13 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.

Bands in the eastern side of Typhoon Mawar’s circulation were still producing gusty winds and locally heavy rain over parts of Guam on Thursday morning. A Flash Flood Warning was in effect for Guam.

Typhoon Mawar intensified after it moved west of the Marianas on Thursday morning. Mawar strengthened to the equivalent of a Category 5 hurricane. A circular eye with a diameter of 26 miles (43 km) was present at the center of Typhoon Mawar. A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Mawar. 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 caused the surface pressure to decrease rapidly.

The size of the circulation around Typhoon Mawar increased after an eyewall replacement cycle finished and Mawar intensified again. Winds to typhoon force extended out 65 miles (105 km) from the center of Typhoon Mawar. 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 36.8. The Hurricane Size Index (HSI) was 19.8 and the Hurricane Wind Intensity Size Index (HWISI) was 56.6. Mawar was bigger and stronger than Hurricane Maria was when Maria hit Puerto Rico in 2017.

Typhoon Mawar will move through an environment favorable for intensification during the next 24 hours. Mawar 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 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. Typhoon Mawar could intensify during the next 24 hours unless a new eyewall replacement cycle begins.

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 will move farther away from the Marianas. Mawar could move south of the Ryukyu Islands in a few days.

Typhoon Nanmadol Rapidly Intensifies to Equivalent of a Major Hurricane

Typhoon Nanmadol rapidly intensified to the equivalent of a major hurricane south of Japan during Thursday night. At 11:00 p.m. EDT on Thursday the center of Typhoon Nanmadol was located at latitude 24.1°N and longitude 135.4°E which put it about 535 miles (860 km) east-southeast of Okinawa. Nanmadol 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 947 mb.

Typhoon Nanmadol rapidly intensified to the equivalent of a major hurricane over the Western North Pacific Ocean south of Japan during Thursday night. A well formed circular eye was present at the center of Nanmadol’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 Nanmadol. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon in all directions.

The circulation around Typhoon Nanmadol was symmetrical. Winds to typhoon force extended out 60 miles (95 km) from the center of Nanmadol. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Nanmadol was 23.6. The Hurricane Size Index (HSI) was 20.6 and the Hurricane Wind Intensity Size Index (HWISI) was 44.2. Typhoon Nanmadol was capable of causing widespread major damage.

Typhoon Nanmadol will move through an environment favorable for intensification during the next 24 hours. Nanmadol will move over water where the Sea Surface Temperatures are near 29˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Typhoon Nanmadol will intensify during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then concentric eyewalls could form. That would be the start of an eyewall replacement cycle that would cause Nanmadol to weaken.

Typhoon Nanmadol will move around the southwestern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Nanmadol toward then northwest during the next 36 hours. On its anticipated track the center of Typhoon Nanmadol will be east of Minami Daito Jima within 24 hours. Nanmadol could be east of Amami Oshima in 36 hours. Typhoon Nanmadol will bring strong, gusty winds and heavy rain to parts of the northern Ryukyu Islands during the weekend.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Muifa weakened over the northern Yellow Sea. At 11:00 p.m. EDT on Thursday the center of Tropical Storm Muifa was located at latitude 38.5°N and longitude 121.8°E which put it about 50 miles (80 km) northeast of Yantai, China. Muifa was moving toward the north-northeast at 16 m.p.h. (26 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.