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Hurricane Dorian Moves Parallel to Florida Coast

Hurricane Dorian moved parallel to the east coast of Florida on Tuesday night.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Dorian was at latitude 28.4°N and longitude 79.0°W which put it about 95 miles (155 km/h) east of Cape Canaveral, Florida.  Dorian was moving toward the north-northwest at 6 m.p.h. (9 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. (215 km/h).  The minimum surface pressure was 959 mb.

Hurricane Warnings were in effect for the portions of the coast from Sebastian Inlet to Ponte Vedra Beach, Florida and from Savannah River, Georgia to Surf City, North Carolina.  Hurricane Watches were in effect for the portion of the coast from Ponte Vedra Beach to Savannah River, Georgia and from Surf City, North Carolina to the North Carolina/Virginia border including Albemarle and Pamlico Sounds.  Tropical Storm Warnings were in effect for the portion of the coast from Jupiter Inlet to Sebastian Inlet, Florida and from Ponte Vedra Beach, Florida to Savannah, River, Georgia.  Tropical Storm Watches were also in effect for the Northwestern Bahamas including the Abacos and Grand Bahama Island.  Tropical Storm Watches were in effect for the portion of the coast from the North Carolina/Virginia border to Chincoteague, Virginia and for Chesapeake Bay south of Smith Point.

Although Hurricane Dorian was moving again, it exhibited the structure of a hurricane that had been stationary for a day and had undergone an eyewall replacement cycle.  There was a large ragged eye with a diameter of 35 miles (55 km) at the center of circulation.  The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Multiple bands of showers and thunderstorms were revolving around the large core of Hurricane Dorian.  Storm near the core were generating upper level divergence which was pumping mass away from the hurricane.

An eyewall replacement cycle caused the size of the circulation around Hurricane Dorian to increase.  Winds to hurricane force extended out about 60 miles (95 km) from the center of circulation.  Wind to tropical storm force extended out about 175 miles (285 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 19.2.  The Hurricane Size Index (HSI) was 19.9 and the Hurricane Wind Intensity Size Index (HWISI) was 39.1.

Hurricane Dorian will move through an environment favorable for intensification on Wednesday.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  However, the large size of Hurricane Dorian will limit potential intensification.  Hurricane Dorian could intensify a little on Wednesday.  An upper level trough over the U.S. will approach Dorian on Wednesday night.  The trough will produce southwesterly winds which will cause more vertical wind shear on Thursday.

Hurricane Dorian will move around the western end of a subtropical high pressure system over the western Atlantic Ocean on Wednesday.  The high will steer Dorian toward the north-northwest.  The upper level trough will turn Dorian toward the northeast on Wednesday night.  On its anticipated track Hurricane Dorian will move nearly parallel to the east coast of Florida on Wednesday.  Dorian could approach the coast of South Carolina by Wednesday night.

Elsewhere Tropical Storm Fernand was over the western Gulf of Mexico and Tropical Depression was west of the Cabo Verde Islands.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Fernand was located at latitude 23.2°N and longitude 96.4°W which put it about 100 miles (155 km) east-southeast of La Pesca, Mexico.  Fernand was moving toward the west at 3 m.p.h. (5 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.  A Tropical Storm Warning was in effect for the portion of the coast from Puerto Altimira, Mexico to the Mouth of the Rio Grande, River.

At 11:00 p.m. EDT on Tuesday the center of Tropical Depression Eight was located at latitude 19.1°N and longitude 32.8°W which put it about 615 miles (995 km) west-northwest of the Cabo Verde Islands.  It was moving toward the northwest at 8 m.p.h. (13 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 1006 mb.

Hurricane Dorian Hammers the Northwestern Bahamas

Hurricane Dorian hammered the Northwestern Bahamas on Monday.  After pounding the Abacos on Sunday night, Hurricane Dorian moved slowly across Grand Bahama Island before stalling over that island for much of Monday.  There were reports of significant storms surges, numerous injuries and some fatalities.  Dorian was still battering Grand Bahama Island on Monday night.

At 11:00 p.m. EDT on Monday the center of Hurricane Dorian was located at latitude 26.9°N and longitude 78.5°W which put it about 30 miles (50 km) north-northeast of Freeport, Bahamas and about 100 miles (160 km) east of West Palm Beach, Florida.  Dorian was essentially stationary.  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 946 mb.

Hurricane Warnings were in effect for the Abacos and Grand Bahama Island.  A Hurricane Warning was also in effect for the portion of the Florida coast from Jupiter Inlet to Ponte Vedra Beach.  Hurricane Watches were in effect for the portions of the coast from Deerfield Beach to Jupiter Inlet and from Ponte Vedra Beach, Florida to South Santee River, South Carolina.  A Tropical Storm Warning was also in effect for the portion of the coast from Deerfield Beach to Jupiter Inlet.  Tropical Storm Watches were in effect for the portion of the coast from Golden Beach to Deerfield Beach and for Lake Okeechobee.

Hurricane Dorian weakened slowly on Monday.  As it remained nearly stationary the winds around Dorian mixed cooler water to the surface.  Hurricane Dorian was unable to extract enough energy from the ocean to maintain its extreme intensity,  The circulation in core of Dorian developed two concentric eyewalls.  The concentric eyewalls suggested that the hurricane had started an eyewall replacement cycle which may have also contributed to the reduction of the wind speed.

The concentric eyewalls also produced an increase in the size of the circulation around Hurricane Dorian.  Winds to hurricane force extended out about 45 miles (75 km) from the center of circulation.  Winds to tropical storm force extended out abou 150 miles from the center.  The Hurricane Intensity Index (HII) was 25.1.  The Hurricane Size Index (HSI) was 15,2 and the Hurricane Wind Intensity Size Index (HWISI) was 40.3.

Hurricane Dorian was south of a high pressure system over the western Atlantic Ocean.  The high was blocking Dorian and preventing the hurricane from moving toward the north.  The western end of the high is forecast to weaken on Tuesday.  When the end of the high weakens, it will allow Hurricane Dorian to move toward the northwest.  An upper level trough over the U.S. will approach Dorian on Wednesday.  The trough is forecast to turn Dorian toward the northeast.  On its anticipated track Hurricane Dorian could approach the Central Florida coast by Tuesday night.  Dorian could approach the Carolinas on Wednesday night.

Hurricane Dorian will move into an environment favorable for intensification when it starts moving again on Tuesday.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  However, Hurricane Dorian could still be in the weakening part of the eyewall replacement cycle and Dorian may not intensify despite the favorable environment.  The upper level trough will produce southwesterly winds which will cause wind shear to increase on Wednesday.  The increase in wind shear will likely cause Hurricane Dorian to weaken when it approaches the Carolinas.

Hurricane Dorian Pounds Northwest Bahamas, Warning Issued for Florida

Hurricane Dorian pounded the Northwestern Bahamas on Sunday afternoon and a Hurricane Warning was issued for a portion of the southeast Florida coast.  Dorian was one of the strongest Atlantic hurricanes on record.  At 5:00 p.m. EDT on Sunday the center of Hurricane Dorian was locate at latitude 26.6°N and longitude 77.3°W which put it about 175 miles (280 km) east of West Palm Beach, Florida.  Dorian was moving toward the west at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 185 m.p.h. (295 km/h) and there were wind gusts to 220 m.p.h. (355 km/h).  The minimum surface pressure was 910 mb.

A Hurricane Warning was issued for the portion of the coast of Florida from Jupiter Inlet to the Volusia/Brevard County Line.  Hurricane Warnings were also in effect for the Northwestern Bahamas including the Abacos, Berry Islands, Bimini, Eleuthera, Grand Bahama Island and New Providence.  Hurricane Watches were in effect for the portion of the coast from Deerfield Beach to Jupiter Inlet, Florida and from the Volusia/Brevard County Line to the Flagler/Volusia County Line.  A Hurricane Watch was also in effect for Andros Island.  A Tropical Storm Warning was in effect for the portion of the coast from Deerfield Beach to Jupiter Inlet, Florida.  Tropical Storm Watches were in effect for the portion of the coast from  Golden Beach to Deerfield Beach, Florida and for Lake Okeechobee.

The core of Hurricane Dorian moved over Great Abaco Island on Sunday afternoon.  Dorian intensified rapidly to an intense Category 5 hurricane on the Saffir-Simpson Scale when it reached the warm water around the Bahamas.  The pressure decreased rapidly to 910 mb and the winds increased to 185 m.p.h. (295 km/h).  There was a circular eye with a diameter of 12 miles (19 km) at the center of Hurricane Dorian.  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 Dorian.  Storms near the core were generating strong upper level divergence which was pumping mass away from the hurricane.

The circulation around Hurricane Dorian increased in size on Sunday.  Winds to hurricane force extended out about 45 miles (75 km) from the center of circulation.  Winds to tropical storm force extended out about 140 miles (220 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 44.1.  The Hurricane Size Index (HSI) was 14,3 and the Hurricane Wind Intensity Size Index (HWISI) was 58.4.  Hurricane Dorian was capable of causing regional catastrophic damage.  Dorian was stronger than Hurricane Andrew was when Andrew hit southeast Florida in 1992.

Hurricane Dorian will remain in a favorable environment for intense hurricanes for another 24 to 36 hours.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  It appeared that an inner rainband may have wrapped around the existing eye and eyewall.  Radar images indicated that there could be two concentric eyewalls.  If there are two eyewalls, then an eyewall replacement cycle is underway.  Hurricane Dorian will weaken, at least temporarily when the inner eyewall dissipates.  However, Dorian will get larger when the strongest winds occur in the outer eyewall.

Hurricane Dorian will move near the western end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Dorian slowly toward the west-northwest during the next 24 to 36 hours.  Eventually, Hurricane Dorian will move more toward the north when it moves around the western end of the high.  On its anticipated track Hurricane Dorian will linger over the Northwestern Bahamas on Sunday night.  The core of Dorian will pass over or very near Grand Bahama Island.  It could cause catastrophic damage on the Abacos and Grand Bahama Island.  Hurricane Dorian could approach the east coast of Florida on Tuesday.

Hurricane Dorian Strengthens to Cat. 5 Near Great Abaco

Hurricane Dorian strengthened to Category 5 on the Saffir-Simpson Scale near Great Abaco Island on Sunday morning.  At 9:30 a.m. EDT on Sunday the center of Hurricane Dorian was located at latitude 26.5°N and longitude 76.5°W which put it about 35 miles (55 km) east of Great Abaco Island, Bahamas and about 225 miles (360 km) east of West Palm Beach, Florida.  Dorian was moving toward the west at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 220 m.p.h. (355 km/h).  The minimum surface pressure was 927 mb.

A Hurricane Warning was in effect for the Northwestern Bahamas including the Abacos, Berry Islands, Bimini, Eleuthera, Grand Bahama Island, and New Providence.  A Hurricane Watch was in effect for Andros Island.  A Tropical Storm Warning was in effect for the portion of the coast from Deerfield Beach to Sebastian Inlet, Florida.  A Tropical Storm Watch was issued for the portion of the coast from Golden Beach to Deerfield Beach, Florida.

A reconnaissance plane found that Hurricane Dorian had strengthened to Category 5 on Sunday morning.  Dorian exhibited the structure of a classic intense hurricane.  There was a circular eye with a diameter of 15 miles (24 km) at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Storms near the core of Hurricane Dorian were generating strong upper level divergence which was pumping mass away from the hurricane.  Bands of showers and thunderstorms were revolving around the core of the hurricane.

Winds to hurricane force extended out about 30 miles from the center of Hurricane Dorian.  Winds to tropical storm force extended out about 110 miles (180 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 40.4.  The Hurricane Size Index (HSI) was 11.7 and the Hurricane Wind Intensity Size Index (HWISI) was 52.1.  Hurricane Dorian was very similar in size and strengthen to what Hurricane Michael was when Michael hit northwest Florida in 2018.

Hurricane Dorian will remain in an environment very favorable for intense hurricanes during the next several days.  Dorian will move over water where the Sea Surface Temperature is 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 Dorian is likely to remain a very strong hurricane for several more days.  At some point a rainband is likely to wrap around the existing eye and eyewall.  When that happens, an eyewall replacement cycle will cause fluctuations in the intensity of Dorian.

Hurricane Dorian will move south of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Dorian toward the west on Sunday.  Hurricane Dorian could slow on Sunday night when it nears the western end of the ridge.  On its anticipated track Hurricane Dorian will move over the Abacos and New Providence on Sunday.  Dorian is capable of causing catastrophic damage over portions of the Northwestern Bahamas.  It could generate a storm surge of 15 feet (4.5 meters) where the strongest winds push water toward the coastline.  Hurricane Dorian could eventually approach the coast of southeast Florida as a very strong hurricane.

Dangerous Hurricane Dorian Nears Northwestern Bahamas

Dangerous Hurricane Dorian neared the Northwestern Bahamas on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Hurricane Dorian was located at latitude 26.3°N and longitude 75.1°W which put it about 125 miles (200 km) east of Great Abaco and about 310 miles (500 km) east of West Palm Beach, Florida.  Dorian was moving toward the west at 8 m.p.h. (13 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. (315 km/h).  The minimum surface pressure was 940 mb.

Hurricane Warnings were in effect for the Northwestern Bahamas including the Abacos, Berry Islands, Bimini, Eleuthera, Grand Bahama Island and New Providence.  A Hurricane Watch was in effect for Andros Island.  A Tropical Storm Watch has been issued for the portion of the coast from Deerfield Beach to Sebastian Inlet, Florida.

Hurricane Dorian remains a very dangerous, well organized storm.  Dorian has maintained Category 4 intensity on the Saffir-Simpson Scale for 24 hours.  A circular eye with a diameter of 15 miles (24 km) was clearly visible on conventional and microwave satellite imagery.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  The maximum sustained wind speed at the surface was 150 m.p.h. (240 km/h) and data from dropsondes indicated that the wind was stronger a few hundred feet above the surface.  Bands of showers and thunderstorms were revolving around the core of Hurricane Dorian.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.

Winds to hurricane force extended out about 30 miles (50 km) from the center of Hurricane Dorian.  Winds to tropical storm force extended out about 105 miles (170 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 33.3.  The Hurricane Size Index (HSI) was 11.7and the Hurricane Wind Intensity Size Index (HWISI) was 45.0.  Hurricane Dorian is capable of causing regional significant damage.

Hurricane Dorian will remain in an environment capable of supporting a very strong hurricane for several more days.  Dorian will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  There will be a potential for Hurricane Dorian to strengthen to Category 5 on the Saffir-Simpson Scale.  At some point eyewall replacement cycles are likely to cause fluctuations in intensity.

Hurricane Dorian will move around the western end of a subtropical high pressure system during the next 24 to 48 hours.  The high will steer Dorian slowly toward the west.  Hurricane Dorian could move very slowly when it reaches the western end of the ridge.  Eventually, Dorian will turn toward the north when it moves around the end of the ridge.  On its anticipated track Hurricane Dorian will reach the Northwestern Bahamas by Sunday evening.  The core of Dorian will move very close to the Abacos and Grand Bahama Island.  Hurricane Dorian could cause significant wind damage.  Dorian could also produce a storm surge of up to 15 feet (4.5 meters) in places where the wind blows water toward the shoreline.

Hurricane Dorian Rapidly Intensifies to Cat. 4

Hurricane Dorian rapidly intensified to Category 4 on the Saffir-Simpson Scale on Friday night and Hurricane Warnings were issued for the Northwestern Bahamas.  At 11:00 p.m. EDT on Friday the center of Hurricane Dorian was located at latitude 25.5°N and longitude 71.4°W which put it about 545 miles (880 km) east of West Palm Beach, Florida,  Dorian was moving toward the west-northwest at 10 m.p.h.  The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 165 m.p.h. (270 km/h).  The minimum surface pressure was 948 mb.

Hurricane Warnings were issued for the Northwestern Bahamas including the Abacos, Berry Islands, Bimini, Eleuthera, Grand Bahama Island and New Providence.  A Hurricane Watch was in effect for Andros Island.

When reconnaissance aircraft reached the core of Hurricane Dorian on Friday night they discovered that Dorian has intensified rapidly since Friday afternoon.  The minimum surface pressure had decreased by more than 20 mb and the maximum sustained wind speed was 140 m.p.h. (220 km/h).  Dorian was a very symmetrical, if small hurricane.  There was a circular eye with a diameter to 14 miles (22 km) at the center of 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 Hurricane Dorian.  Storms around the core were generating upper level divergence which was pumping mass away from the hurricane.

The circulation around Hurricane Dorian was still relatively small.  Winds to hurricane force extended out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out about 110 miles (170 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 28.3.  The Hurricane Size Index (HSI) was 12.0 and the Hurricane Wind Intensity Size Index (HWISI) was 40.3.  Hurricane Dorian was capable of causing regional significant damage.

Hurricane Dorian will remain in an environment favorable for strong hurricanes for several more days.  Dorian will move over water where the Sea Surface Temperature is 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 Dorian could intensify to Category 5 hurricane on the Saffir-Simpson Scale.  At some point a rainband will wrap around the existing eye and eyewall.  That will begin an eyewall replacement cycle that will weaken Hurricane Dorian, at least temporarily.

Hurricane Dorian will move south of a subtropical ridge of high pressure over the western Atlantic Ocean.  The high will steer Dorian toward the west during the next 48 to 72 hours.  Dorian will move much more slowly when it reaches the western end of the ridge.  On its anticipated track Hurricane Dorian could reach the Northwestern Bahamas on Sunday.  Dorian could approach the southeast coast of Florida on Tuesday.

Dorian Strengthens to Major Hurricane

Hurricane Dorian strengthened to a major hurricane on Friday afternoon.  Data from a reconnaissance plane indicated that Hurricane Dorian had strengthened to Category 3 on the Saffir-Simpson Scale on Friday afternoon, which meant it was a major hurricane.  At 2:00 p.m. EDT on Friday the center of Hurricane Dorian was located at latitude 24.8°N and longitude 70.3°W which put it about 625 miles (1005 km) east of West Palm Beach, Florida.  Dorian was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 970 mb.

Hurricane Watches had been issued for the Northwestern Bahamas.

The circulation around Hurricane Dorian exhibited much more impressive organization on satellite images and radar products generated by reconnaissance aircraft.  Clouds cleared out of the eye and it became even more circular.  The diameter of the eye was 21 miles (34 km).  The eye was surround by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  The overall appearance of Hurricane Dorian was more symmetrical.  Bands of showers and thunderstorms were revolving around the core of the circulation.  Storms around the core generating upper level divergence which was pumping mass away from the hurricane.

The circulation around Hurricane Dorian was still small.  Winds to hurricane force extended out about 25 miles from the center of circulation.  Winds to tropical storm force extended out about 100 miles from the center.  The Hurricane Intensity Index (HII) for Dorian was 20.6.  The Hurricane Size Index (HSI) was 9.0 and the Hurricane Wind Intensity Index (HWISI) was 29.6.  Hurricane Dorian was already capable of causing major damage.

Hurricane Dorian will move through an environment that is favorable for intensification.  Dorian will move over water where the Sea Surface Temperature is 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 Dorian could start a period of rapid intensification at any time.  Dorian will almost certainly intensify to Category 4 and there is the potential for it to strengthen to Category 5.  After Hurricane Dorian strengthens, eyewall replacement cycles could cause fluctuations in intensity.

A ridge of high pressure north of Hurricane Dorian is starting to turn Dorian more toward the west.  The high is forecast to steer Dorian toward the west during the next two to three days.  On its anticipated track Hurricane Dorian will be near the Northwestern Bahamas on Sunday and it will approach the southeast coast of Florida on Monday.  Dorian will reach the western end of the high when it gets close to the Florida coast.  Hurricane Dorian could slow down and turn northward on Tuesday.

Typhoon Lekima Moves Through Southern Ryukyu Islands

Powerful Typhoon Lekima moved through the southern Ryukyu Islands on Thursday.  At 5:00 p.m. EDT on Thursday the center of Typhoon Lekima was located at latitude 25.8°N and longitude 124.2°E which put it about 405 miles (655 km) south-southeast of Shanghai, China.  Lekima was moving toward the north-northwest at 13 m.p.h. (20 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. (270 km/h).  The minimum surface pressure was 935 mb.

An inner rainband wrapped around the original eye and eyewall of Typhoon Lekima and a larger outer eye formed around the original eye.  The inner eye remained intact and the strongest winds were occurring in a small ring of thunderstorms around the inner eye.  The diameter of the outer eye was about 60 miles (95 km).  Additional bands of showers and thunderstorms were revolving around the two concentric eyewalls.

The formation of two concentric eyewalls increased the size of the circulation around Typhoon Lekima.  Winds to typhoon force extended out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 275 miles (445 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 28.3.  The Hurricane Size Index (HSI) was 28.1 and the Hurricane Wind Intensity Size Index (HWISI) was 56.4.  Those indices indicated that Typhoon Lekima was capable of causing widespread significant damage.

The inner eye of Typhoon Lekima wobbled between Ishigakijima and Miyakojima on Thursday.  The inner eyewall appeared to pass over Taramajima and Minnajima.  No reports were available from a weather station on Taramajima.  Stations on Ishigakijima and Miyakojima reports winds to tropical storm force, but the strong inner eye passed between those two islands.

The formation of the larger outer eye probably indicates that an eyewall replacement cycle will occur.  Typhoon Lekima will weaken when the inner eyewall dissipates.  However, the circulation will remain large.  Typhoon Lekima will be in an environment favorable for strong typhoons during the next 24 hours.  Lekima will move over water where the Sea Surface Temperature is near 28.5°C.  It will move through a region where the upper level winds are not strong and there will not be a lot of vertical wind shear.  Typhoon Lekima will weaken because of an eyewall replacement cycle, but it will remain a large, powerful typhoon.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the north-northwest during the next several days.  On its anticipated track Typhoon Lekima could approach the coast of China south of Shanghai in about 24 hours.  It is likely to be a large typhoon at that time.

Elsewhere around the Western North Pacific Ocean, Typhoon Krosa was nearly stationary south of Iwo To on Thursday.  At 5:00 p.m. EDT on Thursday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 141.0°E which put it about 195 miles (315 km) south of Iwo To.  Krosa was nearly stationary.  The maximum sustained wind speed was 110 m.p.h. (180 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 950 mb.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 75 miles (120 km) from the center of circulation.  Winds to tropical storm force extended out about 250 miles (405 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Krosa was 19.2.  The Hurricane Size Index (HSI) was 28.4 and the Hurricane Wind Intensity Size Index (HWISI) was 47.6.

Typhoon Krosa is forecast to move slowly north toward Iwo To on Friday.  On its anticipated track Krosa could approach Iwo To in about 36 hours.  It will be a large typhoon capable of causing serious damage at that time.

Typhoons Lekima and Krosa Threaten Japanese Islands

Typhoons Lekima and Krosa threatened Japanese islands on Wednesday.  Typhoon Lekima posed a serious threat to the southern Ryukyu Islands and Typhoon Krosa was headed for Iwo To.  At 5:00 p.m. EDT on Wednesday the center of Typhoon Lekima was located at latitude 22.4°N and longitude 126.0°E which put it about 190 miles (305 km) southeast of Ishigaki, Japan.  Lekmia 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 925 mb.

Typhoon Lekima rapidly intensified into the equivalent of a major hurricane on Wednesday.  A small distinct eye was at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the core were generating strong upper level divergence which was pumping mass away from the typhoon in all directions.

Typhoon Lekima had a large circulation.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Lekima was 23.6.  The Hurricane Size Index (HSI) was 21.6 and the Hurricane Wind Intensity Size Index (HWISI) was 44.7.   Those indices indicated that Typhoon Lekima was capable of causing widespread major damage.

Typhoon Lekima will move through an environment favorable for intensification during the next 24 hours.  Lekima will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will not be a lot of vertical wind shear.  Typhoon Lekima could intensify further during the next day or so.  It is possible that a rainband could wrap around the existing eye and eyewall.  If a rainband wraps around the core of Lekima then an eyewall replacement cycle could cause weakening.

Typhoon Lekima will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Lekima toward the northwest on Thursday.  On its anticipated track Typhoon Lekima will reach Ishigaki and the southern Ryukyu Islands in less than 24 hours.  Lekima will be capable of causing major damage to the southern Ryukyu Islands.  Typhoon Lekima will move more toward the north when it moves around the end of the subtropical ridge.  The center of Lekima could be northeast of Taiwan within 36 hours.  Typhoon Lekima could reach the east coast of China in less than three days.

At 5:00 p.m. EDT on Wednesday the center of Typhoon Krosa was located at latitude 22.1°N and longitude 140.8°E which put it about 210 miles (340 km) south of Iwo To.  Krosa was moving toward the north-northwest at 5 m.p.h. (8 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.

Former Tropical Storm Krosa strengthened into a typhoon on Wednesday.  The inner portion of a rainband wrapped around the center of circulation and an eye formed.  The inner part of the rainband closed around the eye and a circular ring of thunderstorms formed a closed eyewall.  The strongest winds were occurring in the eyewall.  Several bands of showers and thunderstorms were revolving around the core of Typhoon Krosa.  Storms near the center were pumping mass away to the east of the typhoon.

The circulation around Typhoon Krosa was also large.  Winds to typhoon force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 225 miles (360 km) from the center.  The Hurricane Intensity Index for Typhoon Krosa was 11.5.  The Hurricane Size Index was 22.5 and the Hurricane Wind Intensity Size Index was 34.0.

Typhoon Krosa will move through an environment mostly favorable for intensification.  Krosa will move over water where the Sea Surface Temperature is near 29°C.  Upper level divergence from Typhoon Lekima which is to the west of Typhoon Krosa could cause some vertical wind shear.  The wind shear will not be great enough to prevent intensification, but it could slow the rate at which Typhoon Krosa strengthens.

Typhoon Krose will move into a region where the steering winds are weaker.  Typhoon Krosa is forecast to move slowly toward the north during the next two or three days.  On its anticipated track the center of Typhoon Krosa could be near Iwo To in about 48 hours.

Erick Rapidly Intensifies Into Major Hurricane

Erick rapidly intensified into a major hurricane over the the Central Pacific Ocean during Monday night.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Erick was located at latitude 13.4°N and longitude 142.8°W which put it about 920 miles (1485 km) east-southeast of Hilo, Hawaii.  Erick was moving toward the west at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 966 mb.

The core of Hurricane Erick intensified rapidly during the overnight hours.  The eye became more circular and distinct on infrared satellite images.  The diameter of the eye was about 12 miles (19 km) on Tuesday morning.  Thunderstorms in the ring around the eye grew taller and the wind speed around the eye increased quickly.  Storms around the core of Erick generated strong upper level divergence which pumped mass away from the hurricane.  Multiple bands of showers and thunderstorms were revolving around the core of the circulation.

The circulation around Hurricane Erick was relatively small.  Winds to hurricane force were occurring within 25 miles (40 km) of the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) of the center.  The Hurricane Intensity Index (HII) for Hurricane Erick was 20.6.  The Hurricane Size Index (HSI) was 8.2 and the Hurricane Wind Intensity Size Index (HWISI) was 28.8.

Hurricane Erick will remain in an environment favorable for intensification for about another 24 hours.  Erick will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear during the next day or so.  Hurricane Erick will approach an upper level trough east of Hawaii on Wednesday.  The trough will produce stronger southwesterly winds which will cause the vertical wind shear to increase.  Hurricane Erick will start to weaken when the wind shear increases.

Hurricane Erick will move south of a subtropical high pressure system over the Eastern and Central North Pacific Ocean.  The high will steer Erick toward the west during the next several days.  On its anticipated track Hurricane Erick could be south of Hawaii on Thursday night.

Elsewhere, Tropical Storm Flossie was nearing hurricane strength over the Eastern North Pacific Ocean.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Flossie was located at latitude 12.2°N and longitude 120.5°W which put it about 1015 mile (1635 km) southwest of the southern tip of Baja California.  Flossie was moving toward the west at 15 m.p.h. (24 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 999 mb.