Hilary Rapidly Intensifies to a Major Hurricane

Hurricane Hilary rapidly intensified to a major hurricane over the Eastern North Pacific Ocean on Thursday evening. At 11:00 p.m. EDT on Thursday the center of Hurricane Hilary was located at latitude 16.7°N and longitude 110.0°W which put it about 430 miles (690 km) south of Cabo San Lucas, Mexico. Hilary was moving toward the west-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 952 mb.

A Hurricane Watch was in effect for the portion of the coast from Punta Eugenia to Punta Abreojos, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Cabo San Lazaro to Los Barriles, Mexico. The Tropical Storm Warning included Cabo San Lucas. Tropical Storm Watches were in effect for the portions of the coast from Cabo San Lazaro to Punta Eugenia, Mexico and from Los Barriles to Bahia San Juan Bautista, Mexico.

Hurricane Hilary rapidly intensified to a major hurricane on Thursday. An eye with a diameter of 23 miles (37 km) was at the center of Hilary’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 Hurricane Hilary. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Hilary was large. Winds to hurricane force extended out 60 miles (95 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 290 miles (465 km) from the center of circulation. The Hurricane Intensity Index (HII) was 23.6. The Hurricane Size Index (HSI) was 20.3 and the Hurricane Wind Intensity Size Index (HWISI) was 43.9.

Hurricane Hilary will move through an environment favorable for intensification during the next 24 hours. Hilary 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. Hurricane Hilary is likely to continue to intensify during the next 24 hours. Hilary could intensify rapidly at times on Friday.

Hurricane Hilary will move around the western part of a high pressure system over Mexico. The high pressure system will steer Hilary toward the northwest during the next 24 hours. On its anticipated track Hurricane Hilary will move toward Baja California. Hilary will move more toward the north when it reaches the western end of the high pressure system during the weekend. Hurricane Hilary will start to affect Baja California during the weekend.

Elsewhere, former Tropical Storm Greg and former Tropical Storm Fernanda both weakened to tropical depressions. At 11:00 p.m. EDT on Thursday the center of Tropical Depression Greg was located at latitude 12.0°N and longitude 158.5°W which put it about 645 miles (1035 km) south of Honolulu, Hawaii. Greg was moving toward the west at 17 m.p.h. (28 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 1007 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Depression Fernanda was located at latitude 16.4°N and longitude 133.8°W which put it about 1615 miles (2605 km) west-southwest of the southern tip of Baja California. Fernanda was moving toward the west at 15 m.p.h. (24 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 1005 mb.

Hilary Rapidly Intensifies to a Hurricane

Former Tropical Storm Hilary rapidly intensified to a hurricane over the Eastern North Pacific Ocean on Thursday morning. A Tropical Storm Watch was in effect for the southern part of Baja California. At 8:00 a.m. EDT on Thursday the center of Hurricane Hilary was located at latitude 15.2°N and longitude 107.1°W which put it about 320 miles (515 km) southwest of Manzanillo, Mexico. Hilary was moving toward the west-northwest at 13 m.p.h. (21 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 982 mb.

A Tropical Storm Watch was in effect for the portion of the coast of Baja California from Cabo San Lazaro to San Evaristo, Mexico. The Tropical Storm Watch included Cabo San Lucas.

Former Tropical Storm Hilary rapidly intensified to a hurricane on Thursday morning. An eye was visible on satellite images at the center of Hurricane Hilary. 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 Hurricane Hilary. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Hilary was large. Winds to hurricane force extended out 70 miles (110 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 275 miles (445 km) from the center of circulation.

Hurricane Hilary will move through an environment very favorable for intensification during the next 24 hours. Hilary 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. Hurricane Hilary will intensify during the next 24 hours. Hilary could intensify rapidly at times. Hurricane Hilary is likely to strengthen to a major hurricane on Friday.

Hurricane Hilary will move around the western part of a high pressure system over Mexico. The high pressure system will steer Hilary toward the northwest during the next 24 hours. On its anticipated track Hurricane Hilary will move toward Baja California. Hilary will move more toward the north when it reaches the western end of the high pressure system during the weekend. Hurricane Hilary will start to affect Baja California during the weekend.

Elsewhere, Tropical Storm Greg was passing south of Hawaii and Tropical Storm Fernanda continued to weaken. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Greg was located at latitude 12.1°N and longitude 154.5°W which put it about 675 miles (1085 km) south-southeast of Honolulu, Hawaii. Greg was moving toward the west at 13 m.p.h. (21 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 1004 mb.

At 5:00 a.m. EDT on Thursday the center of Tropical Storm Fernanda was located at latitude 16.6°N and longitude 130.8°W which put it about 1425 miles (2290 km) west-southwest of the southern tip of Baja California. Fernanda was moving toward the west at 15 m.p.h. (24 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 1004 mb.

Tropical Storm Hilary Forms South of Mexico

Tropical Storm Hilary formed over the Eastern North Pacific Ocean south of Mexico on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Hilary was located at latitude 12.4°N and longitude 102.6°W which put it about 470 miles (755 km) south-southeast of Manzanillo, Mexico. Hilary was moving toward the west-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 Eastern North Pacific Ocean south of Mexico strengthened on Wednesday morning and the U.S. National Hurricane Center designated the system as Tropical Storm Hilary. The circulation around Tropical Storm Hilary was organizing quickly. Multiple bands of showers and thunderstorms were revolving around the center of Hilary’s circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 200 miles (325 km) in the northeastern quadrant of Tropical Storm Hilary. Winds in the other parts of Hilary’s circulation were blowing at less than tropical storm force.

Tropical Storm Hilary will move through an environment very favorable for intensification during the next 24 hours. Hilary 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. Tropical Storm Hilary will intensify during the next 24 hours. Hilary could intensify rapidly at times. Tropical Storm Hilary is likely to strengthen to a hurricane on Thursday.

Tropical Storm Hilary will move around the western part of a high pressure system over Mexico. The high pressure system will steer Hilary toward the west-northwest during the next 24 hours. On its anticipated track Tropical Storm Hilary will move parallel to the west coast of Mexico. Hilary will move more toward the north when it reaches the western end of the high pressure system during the weekend. Hilary could be near Baja California by Sunday.

Elsewhere, Tropical Storm Greg was spinning southeast of Hawaii and former Hurricane Fernanda weakened to a tropical storm. At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Greg was located at latitude 11.8°N and longitude 151.1°W which put it about 605 miles (975 km) south-southeast of Hilo, Hawaii. Greg was moving toward the west at 14 m.p.h. (22 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 1000 mb.

At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Fernanda was located at latitude 17.1°N and longitude 126.8°W which put it about 1165 miles (1875 km) west-southwest of the southern tip of Baja California. Fernanda was moving toward the west at 15 m.p.h. (24 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 994 mb.

Tropical Storm Lan Moves over the Sea of Japan

Tropical Storm Lan moved over the Sea of Japan on Tuesday. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Lan was located at latitude 38.7°N and longitude 135.8°E which put it about 220 miles (355 km) west-southwest of Akita, Japan. Lan was moving toward the north-northeast at 14 m.p.h. (22 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 989 mb.

Tropical Storm Lan moved over the Sea of Japan on Tuesday after it crossed Honshu near Osaka. Lan weakened to a tropical storm as it crossed over Honshu. The distribution of thunderstorms in Tropical Storm Lan was asymmetrical on Tuesday night. Most of the thunderstorms were occurring in bands in the northern half of Lan’s circulation. Bands in the southern half of the circulation consisted primarily of showers and lower clouds. Storms in the northern half of Lan generated upper level divergence that pumped mass away to the north of the tropical storm. Winds to tropical storm force extended out 150 miles (240 km) from the center of Tropical Storm Lan.

Tropical Storm Lan will move through an environment that will be unfavorable for intensification during the next 36 hours. Lan will move over water where the Sea Surface Temperatures are near 28°C. It will move under the eastern part of an upper level trough that is northwest of Japan. The upper level trough will produce southwesterly winds that will blow toward the top of Lan’s circulation. Those winds will cause moderate vertical wind shear. The moderate wind shear will prevent intensification of Tropical Storm Lan. Lan will begin a transition to an extratropical cyclone in a day or so when it moves over colder water.

The upper level trough that is northwest of Japan will steer Tropical Storm Lan toward the northeast during the next 36 hours. On its anticipated track, The center of Tropical Storm Lan will pass west of Hokkaido in 24 hours. Lan could approach Sakhalin Island in 36 hours.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Dora weakened to a tropical depression north-northeast of Wake Island. At 11:00 p.m. EDT on Tuesday the center of Tropical Depression Dora was located at latitude 25.0°N and longitude 168.4°E which put it about 380 miles (610 km) north-northeast of Wake Island. Dora was moving toward the north-northeast at 14 m.p.h. (22 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 1008 mb.

Tropical Storm Greg Moves Southeast of Hawaii

Tropical Storm Greg moved southeast of Hawaii on Tuesday morning. At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Greg was located at latitude 11.1°N and longitude 145.9°W which put it about 850 miles (1370 km) southeast of Hilo, Hawaii. Greg was moving toward the west at 14 m.p.h. (22 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 1000 mb.

Tropical Storm Greg strengthened a little on Tuesday morning as it moved over the Central Pacific Ocean southeast of Hawaii. Even though Tropical Storm Greg was a little stronger, the distribution of thunderstorms in Greg’s circulation was asymmetrical. Most of the thunderstorms were occurring in bands in the western half of Tropical Storm Greg. Bands in the eastern half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 70 miles (110 km) in the northern half of Greg’s circulation. The winds in the southern half of the circulation were blowing at less than tropical storm force.

Tropical Storm Greg will move through an environment somewhat favorable for intensification during the next 24 hours. Greg will move over water where the Sea Surface Temperatures are near 28°C. It will move under the southwestern part of an upper level ridge over the Eastern North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Greg’s circulation. Those winds will cause moderate vertical wind shear. The wind shear is already contributing to an asymmetrical distribution of thunderstorms. The vertical wind shear may not be strong enough to prevent intensification. So, Tropical Storm Greg could intensify a little more during the next 24 hours.

Tropical Storm Greg will move south of a high pressure system over the eastern and central North Pacific Ocean. The high pressure system will steer Greg toward the west during the next 24 hours. On its anticipated track, Tropical Storm Greg will pass far to the south of Hawaii.

Elsewhere, Hurricane Fernanda weakened gradually over the Eastern North Pacific Ocean. At 11:00 a.m. EDT on Tuesday the center of Hurricane Fernanda was located at latitude 17.0°N and longitude 121.8°W which put it about 875 miles (1405 km) west-southwest of the southern tip of Baja California. Fernanda was moving toward the west-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h). The minimum surface pressure was 967 mb.

Typhoon Lan Makes Landfall in Honshu

Typhoon Lan made landfall in Honshu on Monday. At 5:00 p.m. EDT on Monday the center of Typhoon Lan was located at latitude 33.7°N and longitude 135.9°E which put it about 15 miles (25 km) north of Shingu, Japan. Lan was moving toward the northwest at 8 m.p.h. (13 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 970 mb.

The center of Typhoon Lan made landfall in Wakayama Prefecture near Shingu on Monday. A circular eye with a diameter of 50 miles (80 km) was at the center of Lan’s circulation. A broken ring of 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 Lan.

There was still a large circulation around Typhoon Lan. Winds to typhoon force extended out 70 miles (110 km) from the center of Lan’s circulation. Winds to tropical storm force extended out 145 miles (235 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Lan was 13.9. The Hurricane Size Index (HSI) was 23.0 and the Hurricane Wind Intensity Size Index (HWISI) was 36.9. Typhoon Lan was capable of causing widespread serious damage.

Typhoon Lan 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 Lan toward the north-northwest during the next 24 hours. On its anticipated track, Typhoon Lan will move across Honshu during the next 24 hours. The center of Lan’s circulation will pass near Osaka in a few hours. The center of circulation will also pass west of Kyoto before Lan moves over the Sea of Japan.

Although Typhoon Lan will weaken as it moves across Honshu, Lan will produce strong gusty winds and locally heavy rain over parts of Honshu. Lan will drop heavy rain over Wakayama, Nara, Osaka, Shiga, Kyoto, Hyogo, Tottori, Okayama and Fukui Prefectures. Heavy rain could cause flash floods in some locations. Wind and rain are also likely to cause loss of electricity in widespread areas.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Dora continued to weaken east of Wake Island. At 5:00 p.m. EDT on Monday the center of Tropical Storm Dora was located at latitude 20.9°N and longitude 168.3°E which put it about 145 miles (235 km) east of Wake Island. Dora was moving toward the north-northwest at 11 m.p.h. (17 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 1004 mb.

Fernanda Rapidly Intensifies to a Major Hurricane

Hurricane Fernanda rapidly intensified to a major hurricane over the Eastern North Pacific Ocean during Sunday night. At 5:00 a.m. EDT on Monday the center of Hurricane Fernanda was located at latitude 15.6°N and longitude 117.7°W which put it about 715 miles (1150 km) southwest of the southern tip of Baja California. Fernanda was moving toward the west 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 150 m.p.h. (240 km/h). The minimum surface pressure was 959 mb.

Hurricane Fernanda continued to intensify rapidly during Sunday night. A small eye was at the center of Fernanda’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 revolved around the core of Hurricane Fernanda. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Fernanda was small. Winds to hurricane force extended out 25 miles (40 km) from the center of Fernanda’s circulation. Winds to tropical storm force extended out 70 miles (110 km) from the center of circulation. The Hurricane Intensity Index (HII) was 23.6. The Hurricane Size Index (HSI) was 7.8 and the Hurricane Wind Intensity Size Index (HWISI) was 31.4.

Hurricane Fernanda will move through an environment favorable for intensification during the next 12 hours. Fernanda 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. Hurricane Fernanda is likely to continue to intensify during the next 12 hours. Fernanda will move over slightly cooler water on Tuesday. The cooler water will cause Fernanda to start to weaken.

Hurricane Fernanda will move south of a subtropical high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Fernanda toward the west during the next 24 hours. On its anticipated track, Hurricane Fernanda will move farther away from Baja California.

Elsewhere, Tropical Storm Greg formed east-southeast of Hawaii. At 5:00 a.m. EDT on Monday the center of Tropical Storm Greg was located at latitude 11.3°N and longitude 139.8°W which put it about 1170 miles (1885 km) east-southeast of Hilo, Hawaii. Greg was moving toward the west at 13 m.p.h. (21 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 1005 mb. Tropical Storm Greg is forecast to pass south of Hawaii later this week.

Typhoon Lan Approaches Honshu

Typhoon Lan was approaching Honshu on Sunday night. At 11:00 p.m. EDT on Sunday the center of Typhoon Lan was located at latitude 32.1°N and longitude 137.2°E which put it about 120 miles (195 km) south-southeast of Shingu, Japan. Lan was moving toward the northwest at 9 m.p.h. (15 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 959 mb.

Typhoon Lan strengthened as it approached Honshu on Sunday. A large circular eye with a diameter of 60 miles (95 km) was at the center of Lan’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 large core of Typhoon Lan. Storms near the core generated upper level divergence that pumped mass away from the typhoon.

There was a large circulation around Typhoon Lan. Winds to typhoon force extended out 70 miles (110 km) from the center of Lan’s circulation. Winds to tropical storm force extended out 160 miles (260 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Lan was 16.5. The Hurricane Size Index (HSI) was 21.3 and the Hurricane Wind Intensity Size Index (HWISI) was 37.8. Typhoon Lan was capable of causing widespread serious damage.

Typhoon Lan will move through an environment favorable for intensification during the next 12 hours. Lan 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. Typhoon Lan could continue to strengthen during the next 12 hours as it approaches Honshu.

Typhoon Lan 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 Lan toward the northwest during the next 24 hours. On its anticipated track, the center of Typhoon Lan will make landfall in Wakayama Prefecture south of Osaka in about 18 hours. Lan will produce strong gusty winds and locally heavy rain over parts of Honshu. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Dora continue to weaken east of Wake Island. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Dora was located at latitude 19.0°N and longitude 169.7°E which put it about 235 miles (380 km) east of Wake Island. Dora was moving toward the west-northwest 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 1005 mb.

Fernanda Intensifies to a Hurricane

Former Tropical Storm Fernanda intensified to a hurricane over the Eastern North Pacific Ocean southwest of Baja California on Sunday. At 5:00 p.m. EDT on Sunday the center of Hurricane Fernanda was located at latitude 15.5°N and longitude 116.5°W which put it about 670 miles (1075 km) southwest of the southern tip of Baja California. Fernanda was moving toward the west-northwest at 9 m.p.h. (15 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 995 mb.

Former Tropical Storm Fernanda intensified rapidly to a hurricane on Sunday. The inner end of a rainband wrapped around the center of Hurricane Fernanda’s circulation. A small eye was visible intermittently on satellite images. 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 revolved around the core of Hurricane Fernanda. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Fernanda was small. Winds to hurricane force extended out 15 miles (25 km) from the center of Fernanda’s circulation. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Hurricane Fernanda will move through an environment favorable for intensification during the next 24 hours. Fernanda 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. Hurricane Fernanda will intensify during the next 24 hours. Fernanda could intensify rapidly at times. Fernanda could strengthen to a major hurricane on Monday.

Hurricane Fernanda will move south of a subtropical high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Fernanda toward the west-northwest during the next 24 hours. On its anticipated track, Hurricane Fernanda will move farther away from Baja California.

Typhoon Lan Continues to Move Toward Honshu

Typhoon Lan continued to move to Honshu on Saturday night. At 11:00 p.m. EDT on Saturday the center of Typhoon Lan was located at latitude 30.0°N and longitude 139.1°E which put it about 385 miles (625 km) south of Tokyo, Japan. Lan was moving toward the northwest at 8 m.p.h. (11 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 970 mb.

Typhoon Lan completed an eyewall replacement cyclone on Saturday. The smaller, inner eye and eyewall dissipated. A circular eye with a diameter of 70 miles (110 km) was at the center of Lan’s circulation on Saturday night. The large 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 large eye. Storms around the eye generated upper level divergence that pumped mass away from the typhoon.

The area of typhoon force winds in Typhoon Lan increased during the eyewall replacement cycle. Winds to typhoon force extended out 70 miles (110 km) from the center of Lan’s circulation. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Lan was 11.5. The Hurricane Size Index (HSI) was 21.1 and the Hurricane Wind Intensity Size Index (HWISI) was 32.6.

Typhoon Lan will move through an environment favorable for intensification during the next 24 hours. Lan 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. Typhoon Lan could strengthen during the next 24 hours, since the eyewall replacement cycle is complete.

Typhoon Lan 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 Lan toward the northwest during the next 24 hours. On its anticipated track, Typhoon Lan will approach Honshu in less than 48 hours. The center of Lan could make landfall south of Osaka. Lan will be a typhoon when it reaches Honshu.

Elsewhere over the Western North Pacific Ocean, former Hurricane Dora weakened to a tropical storm East of Wake Island. At 11:00 p.m. EDT on Saturday the center of Tropical Storm Dora was located at latitude 18.2°N and longitude 174.7°E which put it about 570 miles (920 km) east of Wake Island. Dora was moving toward the west-northwest at 14 m.p.h. (22 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 996 mb.