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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.

Tropical Storm Yun-yeung Moves Toward Honshu

Tropical Storm Yun-Yeung moved toward Honshu on Wednesday. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Yun-yeung was located at latitude 30.2°N and longitude 136.7°E which put it about 430 miles (695 km) south-southwest of Tokyo, Japan. Yun-yeung was moving toward the north-northeast at 15 m.p.h. (24 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.

Tropical Storm Yun-yeung consisted primarily of a low level circulation on Wednesday night. The bands revolving around the center of Yun-yeung’s circulation contained primarily showers and lower clouds. A strong upper level trough northwest of Japan produced strong southwesterly winds that blew across the top of Tropical Storm Yun-Yeung. Those winds caused strong vertical wind shear and the winds blew the upper part of Yun-Yeung’s circulation to the northeast of the circulation near the surface . There was a band of thunderstorms near the northern periphery of Tropical Storm Yun-yeung. Winds to tropical storm force extended out 100 miles (160 km) in the eastern side of Yun-Yeung’s circulation. The winds in the western side of Yun-yeung were blowing at less than tropical storm force.

Tropical Storm Yun-yeung will move through an environment unfavorable for intensification of a tropical storm during the next 36 hours. Yun-yeung will move over water where the Sea Surface Temperatures are near 28°C. However, the upper level trough northwest of Japan will continue to cause strong vertical wind shear. The strong vertical wind shear will prevent intensification of Tropical Storm Yun-yeung. Yun-yeung could get a little stronger, if it makes a transition to an extratropical cyclone.

Tropical Storm Yun-yeung will move around the northwestern part of high pressure system over the Western North Pacific. The high pressure system and the upper level trough northwest of Japan will steer Yun-yeung toward the northeast during the next 36 hours. On its anticipated track, Tropical Storm Yun-yeung will approach Tokyo in 36 hours.

Tropical Storm Yun-yeung Forms South of Japan

Tropical Storm Yun-yeung formed over the Western North Pacific Ocean south of Japan on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Yun-yeung was located at latitude 26.2°N and longitude 133.6°E which put it about 810 miles (1305 km) south-southwest of Tokyo, Japan. Yun-yeung was moving toward the north at 17 m.p.h. (28 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.

A low pressure system over the Western North Pacific Ocean strengthened on Tuesday and the Japan Meteorological Agency designated the system as Tropical Storm Yun-yeung. More thunderstorms developed near the center of Yun-yeung’s circulation on Tuesday evening, but the distribution of thunderstorms was asymmetrical. Most of the thunderstorms were occurring in bands in the southern half of Tropical Storm Yun-yeung. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. The distribution of wind speeds was also asymmetrical. Winds to tropical storm force extended out 40 miles (65 km) in the eastern side of Yun-yeung’s circulation. The winds in the eastern side of Yun-yeung were blowing at less than tropical storm force.

Tropical Storm Yun-yeung will move through an environment somewhat favorable for intensification during the next 24 hours. Yun-yeung will move over water where the Sea Surface Temperatures are near 28°C. It will move under the eastern side on an upper level ridge south of Japan. The upper level ridge will produce northeasterly winds that will blow toward the top of Yun-yeung’s circulation. Those winds will cause moderate vertical wind shear. The wind shear is already contributing to the asymmetrical distribution of thunderstorms. The vertical wind shear will inhibit intensification, but the shear will probably not be strong enough to prevent Yun-yeung from strengthening. Tropical Storm Yun-yeung is likely to intensify gradually during the next 24 hours.

Tropical Storm Yun-yeung will move around the northwestern part of high pressure system over the Western North Pacific. The high pressure system will steer Yun-yeung toward the north-northeast during the next 24 hours. On its anticipated track, Tropical Storm Yun-yeung will move closer to Honshu. Yun-yeung could be near Tokyo in 48 hours.

Typhoon Haikui Nears Taiwan

Typhoon Haikui neared Taiwan on Saturday. At 5:00 p.m. EDT on Saturday the center of Typhoon Haikui was located at latitude 22.6°N and longitude 122.7°E which put it about 100 miles (160 km) east-southeast of Taitung, Taiwan. Haikui was moving toward the west at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 958 mb.

Typhoon Haikui intensified as it neared Taiwan on Saturday. A small circular eye was at the center of Haikui’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 Haikui. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

The Taiwan Central Weather Bureau’s radar images indicated that Typhoon Haikui was very symmetrical. Winds to typhoon force extended out 35 miles (55 km) from the center of Haikui’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 Haikui was 17.8. The Hurricane Size Index (HSI) was 9.7 and the Hurricane Wind Intensity Size Index (HWISI) was 27.5. Typhoon Haikui was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Typhoon Haikui will move through an environment favorable for intensification during the next few hours. Haikui will move over water where the Sea Surface Temperatures are near 30°C. It will move under the southern part of an upper level ridge centered north of Taiwan. The ridge will produce easterly winds that will blow toward the top of Haikui’s circulation. The winds in the lower levels of the atmosphere will also blow from the east. So, there will be little vertical wind shear. Typhoon Haikui is likely to continue to intensify during the next few hours until it makes landfall on Taiwan.

Typhoon Haikui will move around the southern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Haikui toward the west- northwest during the next 24 hours. On its anticipated track, the center of Typhoon Haikui will move landfall on the coast of southeast Taiwan near Taitung in nine hours.

Typhoon Haikui will bring strong winds and heavy rain to Taiwan. Haikui will be capable of causing regional serious damage. The heaviest rain will fall on the eastern sides of mountains where the wind will push air up the slopes. Heavy rain is likely to cause flash floods.

Elsewhere over the Western North Pacific Ocean, former Typhoon Saola weakened to a tropical storm along the coast of southern China and former Tropical Storm Kirogi weakened to a tropical depression south of Japan. At 5:00 p.m. EDT on Saturday the center of Tropical Storm Saola was located at latitude 21.6°N and longitude 109.5°E which put it about 35 miles (55 km) east-northeast of Beihai, China. Saola was moving toward the west-southwest at 7 m.p.h. (11 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 991 mb.

At 5:00 p.m. EDT on Saturday the center of Tropical Depression Kirogi was located at latitude 29.6°N and longitude 142.0°E which put it about 370 miles (595 km) south-southeast of Tokyo, Japan. Kirogi was moving toward the northwest at 22 m.p.h. (35 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 1000 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.

Typhoon Saola Churns East of Luzon

Typhoon Saola continued to churn over the Western North Pacific Ocean east of Luzon on Sunday. At 11:00 p.m. EDT on Sunday the center of Typhoon Saola was located at latitude 17.0°N and longitude 124.4°E which put it about 200 miles (320 km) east-southeast of Aparri, Philippines. Saola was moving toward the northeast at 12 m.p.h. (19 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 941 mb.

Microwave satellite images showed that the inner end of a rainband was wrapping around the existing eye and eyewall at the center of Typhoon Saola. If the inner end of the rainband wraps completely around the existing eye and eyewall, then a second, larger outer eyewall would form. The formation of two concentric eyewalls would mark the start of an eyewall replacement cycle. An eyewall replacement cycle would cause Typhoon Saola to weaken.

There was still a small circular eye at the center of Typhoon Saola. The small eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Storms near the center of Saola’s circulation generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Saola was small. Winds to typhoon force extended out 20 miles (30 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 25.1. The Hurricane Size Index (HSI) was 6.9 and the Hurricane Wind Intensity Size Index (HWISI) was 32.0. Typhoon Saola was similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

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. However, an eyewall replacement cycle is likely to cause Typhoon Saola to weaken 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 back toward the north during the next 24 hours. On its anticipated track, Typhoon Saola will move parallel to the coast of northeastern Luzon. Saola could move toward southern Taiwan later this week.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Damrey was passing east of Japan. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Damrey was located at latitude 38.9°N and longitude 145.3°E which put it about 225 miles (360 km) southeast of Misawa, Japan. Damrey was moving toward the north-northeast at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h). The minimum surface pressure was 979 mb.

Typhoon Saola Strengthens to Equivalent of a Major Hurricane

Typhoon Saola strengthened to the equivalent of a major hurricane over the Western North Pacific Ocean near northern Luzon on Saturday morning. At 5:00 a.m. EDT on Saturday the center of Typhoon Saola was located at latitude 17.8°N and longitude 123.3°E which put it about 100 miles (160 km) east-southeast of Aparri, Philippines. Saola was moving toward the south at 6 m.p.h. (10 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 953 mb.

Typhoon Saola rapidly intensified to the equivalent of a major hurricane during the past 24 hours. A small circular eye with a diameter of 12 miles (19 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 Typhoon Saola. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon.

The circulation around Typhoon Saola was small. Winds to typhoon force extended out 30 miles (50 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 22.1. The Hurricane Size Index (HSI) was 10.9 and the Hurricane Wind Intensity Size Index (HWISI) was 33.0. Typhoon Saola was similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

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 is likely to intensify during the next 24 hours.

Typhoon Saola will move around the western side of a large counterclockwise monsoon gyre east of the Philippines. The monsoon gyre will pull Saola toward the southeast during the next 24 hours. A high pressure system over the Western North Pacific Ocean will start to steer Saola back toward the northwest by the end of the weekend. On its anticipated track, Typhoon Saola is forecast to make a slow counterclockwise loop east of Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Damrey was southeast of Japan. At 5:00 a.m. EDT on Saturday the center of Tropical Storm Damrey was located at latitude 26.9°N and longitude 152.1°E which put it about 1020 miles (1645 km) southeast of Tokyo, Japan. Damrey was moving toward the north-northwest at 25 m.p.h. (40 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 987 mb.