Tag Archives: Iwo To

Typhoon Bolaven Passes East of Iwo To

Typhoon Bolaven passed east of Iwo To on Thursday evening. At 11:00 p.m. EDT on Thursday the center of Typhoon Bolaven was located at latitude 26.2°N and longitude 147.8°E which put it about 350 miles (570 km) east of Iwo To. Bolaven was moving toward the northeast at 23 m.p.h. (37 km/h). The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (285 km/h). The minimum surface pressure was 928 mb.

Concentric eyewalls developed at the center of Typhoon Bolaven on Thursday. The inner end of a rainband wrapped around the existing small eye and eyewall. The larger outer eyewall surrounded the inner eye and eyewall. Bands of showers and thunderstorms revolved around the concentric eyewalls. Storms near the eyewalls generated upper level divergence that pumped mass away to the northeast of the typhoon.

The size of Typhoon Bolaven increased when the concentric eyewalls developed. Winds to typhoon force extended out 60 miles (95 km) from the center of Bolaven’s circulation. Winds to tropical storm force extended out 265 miles (425 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Bolaven was 29.9. The Hurricane Size Index (HSI) was 21.3 and the Hurricane Wind Intensity Size Index (HWISI) was 51.2.

Typhoon Bolaven will move through an environment that will become more unfavorable for a powerful typhoon during the next 24 hours. Bolaven will move over water where the Sea Surface Temperatures are near 27°C. It will move under the eastern side of an upper level trough near Japan. The upper level trough will produce southwesterly winds that will blow toward the top of Bolaven’s circulation. Those winds will cause the vertical wind shear to increase. Typhoon Bolaven is likely to weaken during the next 24 hours as it goes through an eyewall replacement cycle and the vertical wind shear increases. Bolaven could make a transition to a strong extratropical cyclone when it moves over cooler water south of Alaska.

The upper level trough near Japan will steer Typhoon Bolaven quickly toward the northeast during the next 24 hours. On its anticipated track, Typhoon Bolaven will pass far to the east of Japan on Friday. Bolaven could move south of the Aleutian Islands during the weekend.

Typhoon Bolaven Gets Even Stronger

Typhoon Bolaven got even stronger on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Typhoon Bolaven was located at latitude 19.3°N and longitude 142.9°E which put it about 420 miles (675 km) south-southeast of Iwo To. Bolaven was moving toward the northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 180 m.p.h. (290 km/h) and there were wind gusts to 220 m.p.h. (355 km/h). The minimum surface pressure was 904 mb.

Typhoon Bolaven grew even more powerful on Wednesday morning. A circular eye with a diameter of 16 miles (26 km) was at the center of Bolaven’s circulation. The eye was surrounded by a 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 Bolaven. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon. The removal of large amounts of mass caused the surface pressure to decrease to 904 mb.

The circulation around Typhoon Bolaven was very symmetrical. Winds to typhoon force extended out 45 miles (65 km) from the center of Bolaven’s circulation. Winds to tropical storm force extended out 195 miles (315 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Bolaven was 42.2. The Hurricane Size Index (HSI) was 18.4 and the Hurricane Wind Intensity Size Index (HWISI) was 60.6. Typhoon Bolaven was similar in intensity to Hurricane Dorian in 2019. Bolaven was bigger than Dorian was.

Typhoon Bolaven will move through an environment favorable for a very powerful typhoon during the next 24 hours. Bolaven 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 Bolaven could maintain its intensity during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then concentric eyewalls could form. If concentric eyewalls form, then an eyewall replacement cycle could cause Typhoon Bolaven to weaken.

Typhoon Bolaven will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Bolaven toward the north during the next 24 hours. On its anticipated track, the Typhoon Bolaven will move closer to Iwo To.

Typhoon Saola Brings Wind and Rain to Hong Kong

Typhoon Saloa brought strong winds and heavy rain to Hong Kong on Friday morning. At 11:00 p.m. EDT on Friday the center of Typhoon Saola was located at latitude 22.1°N and longitude 114.0°E which put it about 20 miles (30 km) southeast of Hong Kong. Saola was moving toward the west at 11 m.p.h. (17 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 938 mb.

Powerful Typhoon Saloa brought strong winds and heavy rain to Hong Kong on Friday morning. The Hong Kong International Airport (VHHH) reported a sustained wind speed of 63 m.p.h. (102 km/h) and a wind gust of 85 m.p.h. (139 km/h). The strongest winds in Typhoon Saola were occurring in the South China Sea just to the south of Hong Kong.

Typhoon Saloa started to weaken just as it approached Hong Kong. Northerly winds blowing around the western side of Saola’s circulation pulled drier air over China into the typhoon. The drier air caused Typhoon Saola to start to weaken. Even though Saola started to weaken, it remained a powerful typhoon. Winds to typhoon force extended out 50 miles (80 km) from the center of Typhoon Saola. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

The Hurricane Intensity Index (HII) for Typhoon Saola was 25.1. The Hurricane Size Index (HSI) was 16.5 and the Hurricane Wind Intensity Size Index (HWISI) was 41.6. Typhoon Saola was capable of causing region major damage.

Typhoon Saola will move south of a high pressure system over China. The high pressure system will steer Saola toward the west-southwest during the next 24 hours. On its anticipated track, Typhoon Saola will move along the coast of Guangdong province.

Typhoon Saola will continue to produce strong winds and heavy rain in Hong Kong during the next few hours. The strong winds could cause widespread outages of electricity. The heavy rain is likely to cause flash floods in some locations. Typhoon Saloa will weaken as it pulls in more drier air. Even though Saola will weaken, strong winds and heavy rain will spread along the coastal part of Guangdong province west of Hong Kong as Typhoon Saola moves toward the west-southwest during the next 24 hours. Strong winds and heavy rain could reach Macau in a few hours.

Elsewhere over the Western North Pacific Ocean, Typhoon Haikui was moving toward Taiwan and Tropical Storm Kirogi weakened east of Iwo To. At 11:00 a.m. EDT on Friday the center of Typhoon Haikui was located at latitude 22.1°N and longitude 127.3°E which put it about 415 miles (670 km) east of Taiwan. Haikui was moving toward the west at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (165 km/h). The minimum surface pressure was 971 mb. Typhoon Haikui could approach Taiwan in 36 hours.

At 11:00 a.m. EDT on Friday the center of Tropical Storm Kirogi was located at latitude 23.9°N and longitude 149.0°E which put it about 475 miles (765 km) east of Iwo To. Kirogi was moving toward the northwest at 20 m.p.h. (32 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 999 mb.

Typhoon Saola Nears Hong Kong

Powerful Typhoon Saola neared Hong Kong on Thursday night. At 11:00 p.m. EDT on Thursday the center of Typhoon Saola was located at latitude 21.9°N and longitude 115.9°E which put it about 140 miles (225 km) east-southeast of Hong Kong. Saola was moving toward the west-northwest at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (265 km/h). The minimum surface pressure was 935 mb.

Powerful Typhoon Saola moved steadily closer to Hong Kong on Thursday night. A circular eye with a diameter of 25 miles (40 km) was at the center of Saola’s circulation. The eye was surrounded by a 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 Saola’s circulation. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon.

The size of the circulation around Typhoon Saola remained relatively constant on Thursday. Winds to typhoon force extended out 50 miles (80 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 28.3. The Hurricane Size Index (HSI) was 17.2 and the Hurricane Wind Intensity Size Index (HWISI) was 45.5. Typhoon Saola was similar in size and intensity to Hurricane Ida when Ida hit Louisiana in 2021.

Typhoon Saola will move through an environment that will become less favorable for intensification during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level ridge winds are weak and there will be little vertical wind shear. However, the circulation around Typhoon Saola could pull in some drier air over China when Saola gets closer to Hong Kong. In addition, if the inner end of a rainband wraps around the existing eye and eyewall, then concentric eyewalls could form. Typhoon Saola is likely to weaken during the next 24 hours, when drier air gets pulled into its circulation.

Typhoon Saola will move around the southern side of a high pressure system over China. The high pressure system will steer Saola toward the west-northwest during the next 24 hours. On its anticipated track, the center of Typhoon Saola will be near Hong Kong in 12 hours.

Typhoon Saola could be the equivalent of a major hurricane when it reaches Hong Kong. Saola will bring strong, gusty winds and locally heavy rain to the area around Hong Kong. Widespread electricity outages are likely. Heavy rain will cause flash floods in some locations. There will also be a significant storm surge where the wind blows the water toward the coast.

Elsewhere over the Western North Pacific Ocean, Typhoon Haikui was moving toward Taiwan and Tropical Storm Kirogi was spinning east-southeast of Iwo To. At 11:00 p.m. EDT on Thursday the center of Typhoon Haikui was located at latitude 22.1°N and longitude 129.1°E which put it about 535 miles (865 km) east of Taiwan. Haikui was moving toward the west at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (150 km/h). The minimum surface pressure was 975 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Storm Kirogi was located at latitude 21.0°N and longitude 150.9°E which put it about 715 miles (1155 km) east-southeast of Iwo To. Kirogi was moving toward the northwest at 18 m.p.h. (30 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.

Powerful Typhoon Saola Moves Between Taiwan and Luzon

Powerful Typhoon Saola moved between Taiwan and Luzon on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Typhoon Saola was located at latitude 20.3°N and longitude 120.7°E which put it about 160 miles (260 km) south-southeast of Kaohsiung, Taiwan. Saola was moving toward the west-northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h). The minimum surface pressure was 922 mb.

Typhoon Saola intensified to the threshold of the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale in Tuesday. A circular eye with a diameter of 15 miles (24 km) was at the center of Saola’ circulation. The eye was surrounded by a 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 Saola’s circulation. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon.

The size of the circulation around Typhoon Saola increased when Saola intensified on Tuesday. Winds to typhoon force extended out 45 miles (75 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 33.3. The Hurricane Size Index (HSI) was 16.2 and the Hurricane Wind Intensity Size Index (HWISI) was 49.5. Typhoon Saola was similar in size and intensity to Hurricane Ian when Ian hit southwest Florida in 2022.

Typhoon Saola will move through an environment favorable for a powerful typhoon during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level ridge winds are weak and there will be little vertical wind shear. Typhoon Saola could maintain much of its intensity during the next 24 hours unless concentric eyewalls for again. If concentric eyewalls form again, then an eyewall replacement cycle would cause Saola to weaken.

Typhoon Saola will move around the southern side of a high pressure system over China. The high pressure system will steer Saola toward the west-northwest during the next 24 hours. On its anticipated track, Typhoon Saola will move over the South China Sea. Saola could be near Hong Kong later this week.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Haikui was southwest of Iwo To. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Haikui was located at latitude 20.2°N and longitude 135.7°E which put it about 457 miles (755 km) southwest of Iwo To. Haikui was moving toward the northwest at 6 m.p.h. (10 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 990 mb.

Typhoon Saola Moves Back Toward Northern Luzon

Typhoon Saola moved back toward northern Luzon on Monday. At 11:00 p.m. EDT on Monday the center of Typhoon Saola was located at latitude 18.8°N and longitude 123.3°E which put it about 115 miles (185 km) east-northeast of Aparri, Philippines. Saola was moving toward the northwest at 6 m.p.h. (10 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 951 mb.

Two concentric eyewalls formed in the core of Typhoon Saola on Monday. A small eye was at the center of Saola’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. A second, slightly larger ring of storms surrounded the inner eyewall. Bands of showers and thunderstorms were revolving around the concentric eyewalls. Storms in the eyewalls generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Saola was small even with the two concentric eyewalls. Winds to typhoon force extended out 25 miles (40 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 20.6. The Hurricane Size Index (HSI) was 9.5 and the Hurricane Wind Intensity Size Index (HWISI) was 30.1. Typhoon Saola was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

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

Typhoon Saola will move around the southwestern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Saola toward the northwest during the next 24 hours. On its anticipated track, Typhoon Saola will move between Luzon and Taiwan in 24 hours.

Typhoon Saola will bring strong winds and heavy rain to the islands north of Luzon. Saola could also drop heavy rains over parts of northern Luzon. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Damrey moved quickly away from Japan and Tropical Storm Haikui formed south of Iwo To. At 11:00 p.m. EDT on Monday the center of Tropical Storm Damrey was located at latitude 41.2°N and longitude 152.3°E which put it about 285 miles (460 km) east-southeast of Hamanaka, Japan. Damrey was moving toward the east at 25 m.p.h. (40 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 990 mb.

At 11:00 p.m. EDT on Monday the center of Tropical Storm Haikui was located at latitude 19.2°N and longitude 137.6°E which put it about 450 miles (725 km) south-southwest of Iwo To. Haikui was moving toward the west-northwest at 17 m.p.h. (28 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 995 mb.

Tropical Storm Khanun Hits South Korea

Tropical Storm Khanun hit South Korea on Wednesday night. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Khanun was located at latitude 35.5°N and longitude 128.4°E which put it about 20 miles (30 km) south-southeast of Chinhae, South Korea. Khanun was moving toward the north at 13 m.p.h. (21 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 984 mb.

Tropical Storm Khanun hit the southern coast of South Korea on Wednesday night. The center of Khanun made landfall near Busan and Chinhae. Tropical Storm Khanun brought gusty winds and locally heavy rain to the southern half of South Korea. Winds to tropical storm force extended out 175 miles (285 km) from the center of Khanun’s circulation.

Tropical Storm Khanun 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 Khanun toward the north-northwest. On its anticipated track, the center of Tropical Storm Khanun will be near Seoul in less than 12 hours. Khanun will continue to produce gusty winds and locally heavy rain in South Korea on Thursday. Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Lan intensified to a typhoon. At 11:00 p.m. EDT on Wednesday the center of Typhoon Lan was located at latitude 25.4°N and longitude 143.7°E which put it about 165 miles (265 km) east of Iwo To. Lan was moving toward the west at 7 m.p.h. (11 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 975 mb. Typhoon Lan is forecast to move toward Honshu and to strengthen.

Tropical Storm Khanun Brings Wind and Rain to Kyushu

Tropical Storm Khanun brought wind and rain to Kyushu on Tuesday. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Khanun was located at latitude 31.2°N and longitude 129.1°E which put it about 85 miles (135 km) west-southwest of Kagoshima, Japan. Khanun was moving toward the northwest at 7 m.p.h. (11 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 979 mb.

Bands in the eastern side of Tropical Storm Khanun brought winds and rain to Kyushu on Tuesday. There was an elliptical area of relatively clear skies at the center of Khanun’s circulation. A broken ring of thunderstorms with a diameter of 70 miles (110 km) surrounded the relatively clear area. The strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Tropical Storm Khanun. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 175 miles (280 km) from the center of Khanun’s circulation.

Tropical Storm Khanun will move through an environment that will be somewhat favorable for intensification during the next 24 hours. Khanun will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Khanun could intensify a little during the next 24 hours.

Tropical Storm Khanun will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Khanun toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Khanun will make landfall in South Korea in less than 24 hours. Khanun will bring gusty winds and locally heavy rain to South Korea. Heavy rain could cause flash floods in some locations. Bands in the eastern side of Tropical Storm Khanun will continue to produce gusty winds and locally heavy rain in Kyushu during the next 24 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Lan intensified east of Iwo To. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Lan was located at latitude 24.4°N and longitude 146.6°E which put it about 335 miles (540 km) east of Iwo To. Lan was moving toward the west at 7 m.p.h. (11 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 988 mb.

Tropical Storm Khanun Moves Toward Kyushu

Tropical Storm Khanun started to move toward Kyushu on Monday. At 11:00 p.m. EDT on Monday the center of Tropical Storm Khanun was located at latitude 29.1°N and longitude 130.7°E which put it about 195 miles (315 km) south of Kagoshima, Japan. Khanun was moving toward the north-northwest at 5 m.p.h. (8 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 981 mb.

Tropical Storm Khanun weakened on Monday. There still were no thunderstorms near the center of Khanun’s circulation. A large, mostly clear area was at the center of Tropical Storm Khanun. There were bands of showers and lower clouds within the mostly clear area. A broken ring of thunderstorms with a diameter of 90 miles (145 km) surrounded the mostly clear area. The strongest winds were occurring in the broken ring of storms. Storms in the ring generated upper level divergence that pumped mass away from the tropical storm. There were also bands of showers and thunderstorms outside the broken ring. Winds to tropical storm force extended out 200 miles (325 km) from the center of Tropical Storm Khanun.

Tropical Storm Khanun will move through an environment that will be somewhat favorable for intensification during the next 24 hours. Khanun will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. If Tropical Storm Khanun intensifies during the next 24 hours, it is likely to strengthen slowly, because of the lack of thunderstorms in the inner core of its circulation. If thunderstorms form closer to the center of Khanun’s circulation, then it could start to intensify a little faster.

Tropical Storm Khanun will move around the western part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Khanun toward the north-northwest during the next 24 hours. On its anticipated track, The center of Tropical Storm Khanun will be west of Kyushu in 24 hours. Bands in the eastern side of Tropical Storm Khanun will produce gusty winds and locally heavy rain in Kyushu. Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Lan formed southeast of Japan. At 11:00 p.m. EDT on Monday the center of Tropical Storm Lan was located at latitude 24.6°N and longitude 148.8°E which put it about 485 miles (780 km) south of Kagoshima, Japan. Lan was moving toward the northwest 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 988 mb.

Typhoon Guchol Turns Northeast

Typhoon Guchol turned toward the northeast on Saturday as it moved over the Western North Pacific Ocean. At 5:00 p.m. EDT on Saturday the center of Typhoon Guchol was located at latitude 22.6°N and longitude 131.3°E which put it about 215 miles (345 km) south of Minamidiatojima, Japan. Guchol was moving toward the north-northeast at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h). The minimum surface pressure was 969 mb.

Typhoon Guchol started to turn toward the northeast on Saturday, as it was affected by an upper level trough west of Japan. The upper level trough was producing westerly winds that were blowing toward the top of Guchol’s circulation. Those winds were causing the vertical wind shear to increase and the increasing shear was affecting the structure of Typhoon Guchol. There was still an eye at the center of Guchol’s circulation, but thunderstorms were only occurring in the eastern part of the eyewall. Thunderstorms were also occurring in bands in the eastern half of the typhoon. Bands in the western half of Typhoon Guchol consisted primarily of showers and low clouds. Storms in the eastern side of Guchol generated upper level divergence that pumped mass away to the northeast of the typhoon. Winds to typhoon force extended out 75 miles (120 km) from the center of Guchol. Winds to tropical storm force extended out 185 miles (295 km) from the center of circulation.

Typhoon Guchol will move through an environment that will become even less favorable for intensification during the next 24 hours. Guchol will move over water where the Sea Surface Temperatures are near 28˚C. The upper level trough west of Japan will continue to produce westerly winds that will blow toward the top of Guchol’s circulation. Those winds will cause the vertical wind shear to increase even more. The increase in wind shear will make the environment even less favorable for intensification. Typhoon Guchol will weaken during the next 24 hours.

The upper level trough west of Japan will steer Typhoon Guchol toward the northeast during the next 48 hours. On its anticipated track Typhoon Guchol could pass between Minamidaitojima and Iwo To during the next 24 hours. Guchol will pass south of Tokyo in less than 48 hours.