Author Archives: jay_hobgood

Michael Strengthens to a Major Hurricane

Hurricane Michael strengthened into a major hurricane on Tuesday afternoon.  At 5:00 p.m. EDT on Tuesday the center of Hurricane Michael was located at latitude 26.0°N and longitude 86.4°W which put it about 290 miles (470 km) south of Panama City, Florida.  Michael was moving toward the north at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 957 mb.

A Hurricane Warning is in effect for the portion of the coast from the Alabama-Florida border to the Suwanee River, Florida.  Tropical Storm Warnings are in effect for the portions of the coast from the Alabama-Florida border to the Alabama-Mississippi border, from Suwanee River to Chassahowitzka, Florida and from Fernandina Beach, Florida to South Santee River, South Carolina on the Atlantic Coast.  Tropical Storm Watches are in effect for the portions of the coast from the Alabama-Mississippi border to the Mouth of the Pearl River, from Chassahowitzka to Anna Maria Island, Florida and from South Santee, River South Carolina to Duck, North Carolina including Albemarle and Pamlico Sounds.

The inner core of Hurricane Michael tightened on Tuesday afternoon.  The diameter of the eye decreased from 30 miles (50 km) to 22 miles (35 km).  The ring of thunderstorms around the eye tightened around the smaller eye and the strongest winds were closer to the center of circulation.  Storms around the core of Michael were generating upper level divergence which was pumping mass away from the hurricane.  The removal of mass allowed the surface pressure to decrease from 965 mb to 957 mb during the past six hours.

Winds to hurricane force extend out about 45 miles (75 km) from the center of Hurricane Michael.  Winds to tropical storm force extend out about 170 miles (280 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Michael is 22.1.  The Hurricane Size Index (HSI) is 14.6 and the Hurricane Wind Intensity Size Index (HWISI) is 36.7.  Hurricane Michael is capable of causing regional major damage.

Hurricane Michael will move through an environment favorable for intensification for another 12 to 18 hours.  Michael will move over water where the Sea Surface Temperature is near 29°C.  An upper level trough over the Central U.S. is producing westerly winds which are blowing toward the top of Hurricane Michael, but those winds are not causing enough vertical wind shear to prevent intensification.  Hurricane Michael could intensify to Category 4 on the Saffir-Simpson Scale before it makes landfall.

Hurricane Michael is moving between a subtropical high pressure system over the western Atlantic Ocean and the upper level trough over the Central U.S.  Those two weather systems are steering Michael toward the north and that general motion is expected to continue for another 12 hours.  On its anticipated track Hurricane Michael will make landfall near Panama City and Port St. Joe, Florida early on Wednesday afternoon.  The upper level trough will steer Michael more toward the northeast after it makes landfall.  The center of Michael is likely to move between Dothan, Alabama and Tallahassee, Florida and it could pass near Albany, Georgia.

Hurricane Michael will bring strong winds to northwest Florida, extreme southeast Alabama and southern Georgia.  There will be wind damage and widespread power outages could occur.  The coast of the northeastern Gulf of Mexico is very vulnerable to storm surges.  Hurricane Michael will produce a storm surge of 10 to 15 feet (3 to 5 meters) at some points along the coast.  Michael will drop locally heavy rain.  Although Hurricane Michael will weaken when it moves inland, it will bring gusty winds and heavy rain to South Carolina and North Carolina.  Hurricane Michael will hinder efforts in those states to recover from the effects of Hurricane Florence.

Hurricane Sergio Turns Back Toward Baja California

Hurricane Sergio turned back toward Baja California on Tuesday morning.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Sergio was located at latitude 16.6°N and longitude 127.4°W which put it about 1215 miles (1960 km) west-southwest of the southern tip of Baja California.  Sergio was moving toward the northeast at 7 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 95 m.p.h. (155 km/h).  The minimum surface pressure was 982 mb.

Hurricane Sergio was slowly weakening.  It appeared that cooler, drier air was entering the western half of the circulation.  Sergio has been moving slowly and its winds may have mixed some cooler water to the surface of the ocean.  Rainbands on the western side of Sergio consisted primarily of showers and lower clouds and thunderstorms in western side of the eyewall were weakening.  Stronger thunderstorms were still occurring in the eastern side of the eyewall and that was where the strongest winds were occurring.  Some strong storms were also occurring in a band southeast of the center of circulation.

Hurricane Sergio will move through an environment that will cause it to continue to weaken slowly.  Sergio is currently over water where the Sea Surface Temperature is near 27°C, but it will move over cooler water in a day or so.  An upper level trough centered west of California will produce southwesterly winds which will cause more vertical wind shear.  The combination of cooler water and more wind shear will cause Hurricane Sergio to weaken to a tropical storm within the next 24 to 36 hours.

The upper level trough will steer Hurricane Sergio toward the northeast during the next several days.  On its anticipated track Sergio could approach central Baja California on Thursday night.  It will likely be a tropical storm at that time.  Tropical Storm Watches could be issued for parts of the coast later today or on Wednesday.  Sergio will bring gusty winds and it will drop locally heavy rain.  The rain could cause flash flooding.  Sergio could also bring some rain to New Mexico and west Texas during the weekend.

Tropical Cyclone Titli Forms Over Bay of Bengal

Tropical Cyclone Titli formed over the Bay of Bengal on Tuesday.  At 11:00 a.m. EDT on Tuesday the center of Tropical Cyclone Titli was located at latitude 15.4°N and longitude 86.3°E which put it about 265 miles (425 km) southeast of Visakhapatnam, India.  Titli was moving toward the north-northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 997 mb.

A distinct center of circulation formed within a large cluster of thunderstorms over the Bay of Bengal and the Indian Meteorological Department designated the system as Tropical Cyclone Titli.  The circulation of Titli was still organizing.  Bands of showers and thunderstorms were forming close to the center of circulation on the western side of the tropical cyclone.  Other bands of showers and thunderstorms were forming on the periphery of the eastern side of the circulation.  Storms near the center of Titli were starting to generate upper level divergence which was pumping mass away from the tropical cyclone.

Tropical Cyclone Titli will be moving through an environment favorable for intensification during the next 36 hours.  Titli will move over water where the Sea Surface Temperature is near 30°C.  It will move under the western end of an upper level ridge.  The ridge will produce southeasterly winds which will blow toward the top of the circulation, but the vertical wind shear will not be strong enough to prevent intensification.  Tropical Cyclone Titli is forecast to strengthen into the equivalent of a hurricane/typhoon during the next 24 to 36 hours.

The upper level ridge will steer Tropical Cyclone Titli slowly toward the north-northwest during the next two days.  On its anticipated track Tropical Cyclone Titli will make landfall on the coast of India near Brahmapur in about 36 hours.  Titli will likely be the equivalent of a hurricane/typhoon when it makes landfall.  It will bring strong winds and heavy rain to parts of northeastern India.  The strong winds will produce a storm surge of 6 to 9 feet (2 to 3 meters) at the coast.  The heavy rain could cause flash flooding when Tropical Cyclone Titli moves inland.

Elsewhere over the northern Indian Ocean, Tropical Cyclone Luban was gradually strengthening over the Arabian Sea.  At 11:00 a.m. EDT on Tuesday the center of Tropical Cyclone Luban was located at latitude 13.5°N and longitude 59.5°E which put it about 450 miles (725 km) east-southeast of Salalah, Oman.  Luban was moving toward the west-northwest at 5 m.p.h. (8 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 990 mb.

Tropical Cyclone Luban Forms Over Arabian Sea

Tropical Cyclone Luban formed over the Arabian Sea on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Cyclone Luban was located at latitude 12.3°N and longitude 61.4°E which put it about 580 miles (935 km) east-southeast of Salalah, Oman.  Luban was moving toward the west-northwest at 4 m.p.h. (6 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 993 mb.

The circulation around Tropical Cyclone Luban was still organizing.  The distribution of thunderstorms was asymmetrical.  Many of the stronger thunderstorms were occurring in bands west of the center of circulation.  Rainbands in the eastern half of Tropical Cyclone Luban consisted primarily of showers and lower clouds.  An upper level trough centered over northern India was producing easterly winds which were blowing toward the top of the circulation.  Those winds were causing moderate vertical wind shear and they were probably the reason why the stronger thunderstorms were forming on the western side of the circulation.

Tropical Cyclone Luban will move through a region that is somewhat favorable for intensification.  It will move over water where the Sea Surface Temperature is near 29°C.  The upper level ridge will continue to cause some vertical wind shear, but the winds are expected to weaken during the next day or two.  Tropical Cyclone Luban is forecast to strengthen into the equivalent of a hurricane/typhoon.

Tropical Cyclone Luban is between the upper level ridge over India and another upper level ridge over Saudi Arabia.  As a result the steering winds are weak and Luban is moving slowly toward the west-northwest.  When Tropical Cyclone Luban moves farther west, the upper ridge over Saudi Arabia will steer it in a west-northwesterly direction.  On its anticipated track Tropical Cyclone Luban could approach western Oman and eastern Yemen in four or five days.

Michael Strengthens Into a Hurricane, Watches Issued for Gulf Coast

Former Tropical Storm Michael strengthened into a hurricane on Monday morning and Watches were issued for portions of the Gulf Coast.  At 11:00 a.m. EDT on Monday the center of Hurricane Michael was located at latitude 21.2°N and longitude 84.9°W which put it about 50 miles (80 km) south of the western end of Cuba.  Michael was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 982 mb.

A Hurricane Watch was in effect for the portion of the coast from the Alabama-Florida border to Suwanee River, Florida.  Tropical Storm Watches were in effect for the portions of the coast from the Alabama-Florida border to the Alabama-Mississippi border and from Suwanee River to Anna Maria Island, Florida.  A Hurricane Warning was in effect for the Cuban province of Pinar del Rio.  Tropical Storm Warnings were in effect for the Cuban province of Isle of Youth and for the portion of the coast from Tulum to Cabo Catoche, Mexico.

Hurricane Michael continued to organize quickly.  A circular eye with a diameter of about 30 miles (50 km) was forming at the center of Michael.  A ring of strong thunderstorms was wrapping around the eye and the strongest winds were occurring in the ring of storms.  Several bands of showers and thunderstorms were wrapping around the core of Hurricane Michael.  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) primarily to the northeast of the center of Hurricane Michael.  Winds to tropical storm force extended out about 175 miles (280 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Michael was 10.4.  The Hurricane Size Index (HSI) was 6.8 and the Hurricane Wind Intensity Size Index (HWISI) was 17.2.

Hurricane Michael will move into an environment that will become increasingly favorable for intensification.  Michael will move over water where the Sea Surface Temperature is near 30°C.  An upper level trough over the Gulf of Mexico was producing westerly winds which were blowing toward the top of the circulation.  Those winds were causing some vertical wind shear.  However, the upper level trough will move westward away from Hurricane Michael and the wind shear will decrease.  Hurricane Michael will continue to strengthen when it moves over the Gulf of Mexico and it could intensify rapidly once the eye and eyewall are fully formed.  Hurricane Michael is likely to strengthen into a major hurricane.

Hurricane Michael will move around the western end of a subtropical high pressure system centered over the western Atlantic Ocean.  The high will steer Michael in a northerly direction during the next several days.  It will get bigger and stronger during the next 48 hours.  On its anticipated track Hurricane Michael will approach the northeast coast of the Gulf of Mexico on Wednesday.  It is likely to be a major hurricane at that time.  Hurricane Michael has the potential to cause a storm surge of 10 to 15 feet (3 to 5 meters) at the coast.  It will bring strong winds which could cause regional major damage and result in significant power outages.  Locally heavy rain could cause flooding in some locations.

Tropical Storm Michael Strengthens East of Yucatan

Tropical Storm Michael strengthened east of the Yucatan peninsula on Sunday.  At 8:00 p.m. EDT on Sunday the center of Tropical Storm Michael was located at latitude 19.9°N and longitude 85.4°W which put it about 105 miles (170 km) east-southeast of Cozumel, Mexico.  Michael was moving toward the north at 5 m.p.h. (8 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 997 mb.

A Tropical Storm Warning was in effect for the Cuban provinces of Pinar del Rio and the Isle of Youth.  A Tropical Storm Warning is also in effect for the portion of the coast from Tulum to Cabo Catoche, Mexico.

The circulation around Tropical Storm Michael is still organizing and the distribution of thunderstorms is asymmetrical.  Most of the thunderstorms are occurring in bands in the eastern half of the circulation.  A new center of circulation formed on Sunday afternoon near those thunderstorms.  Many of the rainbands in the western half of Tropical Storm Michael contain primarily showers and lower clouds.  One outer rainband in the southwestern periphery of the circulation does contain numerous thunderstorms.  The strongest winds are occurring in the rainbands on the eastern side of Tropical Storm Michael.  The winds are weaker on the western side of the circulation.  Storms on the eastern side of Michael are generating some upper level divergence which was pumping mass away from the tropical storm and was allowing the surface pressure to decrease.

An upper level trough over the Gulf of Mexico is producing westerly winds which are blowing across the top of Tropical Storm Michael.  Those winds are causing moderate vertical wind shear which was slowing the rate of intensification, but the shear is not strong enough to prevent Michael from strengthening.  The wind shear is probably the reason for the asymmetrical distribution of thunderstorms.  The upper level trough will move westward during the next few days and the upper level winds will weaken.  Michael will move over water where the Sea Surface Temperature is warmer than 30°C.  Tropical Storm Michael will strengthen slowly during the next 24 hours.  However, it will intensify more rapidly on Tuesday when the upper level winds weaken.  Michael will strengthen into a hurricane when it moves over the Gulf of Mexico and it could intensify into a major hurricane.

Tropical Storm Michael has been moving slowly while the circulation organizes and the center reforms.  Michael will move around the southwestern part of the subtropical high pressure system over the western North Atlantic Ocean.  The high will steer Michael in a northward direction during the next two or three days.  On its anticipated track the center of Tropical Storm Michael will pass between the western end of Cuba and the Yucatan peninsula on Monday.  Michael could approach northern Florida by Wednesday.  It will be a hurricane at that time and it could be a major hurricane.  Michael could produce strong winds, a significant storm surge and drop heavy rain when it reaches the coast.

Typhoon Kong-rey Brings Wind and Rain to South Korea

Typhoon Kong-rey brought wind and rain to South Korea late on Friday.  At 5:00 p.m. EDT on Friday the center of Typhoon Kong-rey was located at latitude 33.8°N and longitude 127.7°W which put it near Jeju (Cheju) Island and about 150 miles (240 km) southwest of Pusan, South Korea.  Kong-rey was moving toward the north-northeast at 20 m.p.h. (32 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 970 mb.

Rainbands on the northern side of the circulation of Typhoon Kong-rey were already dropping heavy rain over parts of South Korea.  The core of Kong-rey was bringing winds to typhoon force and heavy rain to Jeju (Cheju) Island.  Typhoon Kong-rey was moving quickly toward the north-northeast.  On its anticipated track the center of Typhoon Kong-rey will pass near Pusan, South Korea in a few hours.  The typhoon will bring gusty winds and drop locally heavy rain when it passes over southeastern South Korea.  Kong-rey will weaken when it moves over the cooler water in the Sea of Japan.  Kong-rey could be near Hokkaido in about 24 hours.  It will be a tropical storm at that time, but it could still drop locally heavy rain.

Possible Tropical Development Near Yucatan Peninsula

A tropical cyclone could develop near the Yucatan peninsula during the next few days.  At 2:00 p.m. EDT on Friday the center of Invest 91L was located at latitude 16.0°N and longitude 84.3°W which put it about 400 miles (640 km) southeast of Cancun, Mexico.  It was moving toward the northwest at 6 m.p.h. (10 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 1007 mb.

A broad area of low pressure is over the western Caribbean Sea, Central America and the adjacent waters of the Eastern North Pacific Ocean.  Several smaller, mesoscale centers of rotation appear to be revolving around the larger low pressure system.  One of the mesoscale centers is over the Eastern North Pacific Ocean just west of the coast of Central America.  One or two other mesoscale centers appear to be over the western Caribbean Sea near Honduras.  The low level circulation is not currently well organized.  It is broad and diffuse.  Thunderstorms are clustered around the mesoscale centers, but large scale rainbands have not formed.

Westerly winds in the upper levels are are blowing over the top of the system.  Those winds are creating moderate vertical wind shear which is inhibiting the development of the low pressure system.  The upper level winds are forecast to weaken during the next few days and the wind shear will diminish.  The Sea Surface Temperature of the water in the northwestern Caribbean Sea and Gulf of Mexico is near 30°C.  The broad low pressure system could slowly organize during the next two to three days.  The National Hurricane Center is indicating that there is a 70% probability of formation of a tropical cyclone near the Yucatan peninsula or over the southern Gulf of Mexico during the next five days.  A reconnaissance plane is scheduled to investigate the low pressure system on Sunday, if necessary.

The broad low is southwest of a subtropical high pressure system over the Atlantic Ocean.  The high is expected to steer the low toward the northwest during the weekend.  On its anticipated track the low will move over the northwestern Caribbean Sea during the next several days.  it could move into the Gulf of Mexico on Monday.

Elsewhere over the Atlantic Ocean, Tropical Storm Leslie continued to meander northeast of Bermuda.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Leslie was located at latitude 36.2°N and longitude 58.4°W which put it about 455 miles (730 km) northeast of Bermuda.  Leslie was moving toward the north-northwest at 9 m.p.h. (15 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 986 mb.

Typhoon Kong-rey Brings Wind and Rain to Okinawa

Typhoon Kong-rey was bringing wind and rain to Okinawa on Wednesday night.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Kong-rey was located at latitude 23.6°N and longitude 127.3°W which put it about 230 miles (375 km) south of Okinawa.  Kong-rey was moving toward the northwest at 10 m.p.h. (16 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 964 mb.

Typhoon Kongrey weakened steadily during Wednesday.  The eye became less distinct on satellite imagery.  The ring of strong thunderstorms around the eye broke and stronger thunderstorms were only occurring to the east of the eye.  It appeared that Typhoon Kong-rey was pulling cooler, drier air into the western half of the circulation and that air was wrapping around the southern half of the typhoon.  Kong-rey may have also moved over some cooler water that was mixed to the surface by Typhoon Trami last week.

The circulation around Typhoon Kong-rey was still large.  Winds to typhoon force extended out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extended out about 230 miles (375 km) from the center.  The Hurricane Intensity Index (HII) for Typhoon Kong-rey was 11.5.  The Hurricane Size Index (HSI) was 24.7 and the Hurricane Wind Intensity Size Index (HWISI) was 36.2.

Typhoon Kong-rey will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Kong-rey toward the north during the next 24 to 36 hours.  Typhoon Kong-rey will turn more toward the northeast in about 36 hours.

The outer rainbands on the northern side of Typhoon Kong-rey are already over Okinawa.  Kong-rey will drop heavy rain and it will produce gusty winds over Okinawa and the Ryukyu Islands on Thursday.  The wind and rain will hinder efforts to recover from damage caused by Typhoon Trami.  Typhoon Kong-rey could be southeast of Kyushu in about 36 hours and it could be near South Korea in about 48 hours.  The soil in much of Japan is already near saturation and more heavy rain could cause flash flooding.  Typhoon Kong-rey could also hinder recovery efforts in Kyushu, Shikoku and Honshu.

Major Hurricane Sergio Churns Southwest of Baja California

Major Hurricane Sergio churned southwest of Baja California.  At 5:00 p.m. EDT on Wednesday the center of Hurricane Sergio was located at latitude 13.3°N and longitude 117.9°W which put it about 845 miles (1360 km) southwest of the southern tip of Baja California.  Sergio was moving toward the northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 955 mb.

Hurricane Sergio is a well organized hurricane.  There is a circular eye at the center of circulation.  A ring of strong thunderstorms surrounds the eye and the strongest winds are occurring in that ring of storms.  Several bands of showers and thunderstorms are revolving around the core of Hurricane Sergio.  Storms near the core are generating strong upper level divergence which is pumping mass away in all directions from the hurricane.

Winds to hurricane force extend out about 45 miles (75 km) from the center of Hurricane Sergio.  Winds to tropical storm force extend out about 150 miles (240 km) from the center of circulation.  The Hurricane intensity Index (HII) for Hurricane Sergio is 23.6.  The Hurrricane Size Index (HSI) is 15.1 and the Hurricane Wind Intensity Size Index (HWISI) is 38.7.

Hurricane Sergio will remain in an environment capable of supporting a major hurricane for several more days.  Sergio will move over water where the Sea Surface Temperature is near 28°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Sergio could strengthen to Category 4 on the Saffir-Simpson Scale.  Hurricane Sergio will move over cooler water in a couple of days and it is likely to weaken when that occurs.

Hurricane Sergio will move south of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge will steer Sergio toward the northwest during the next day or so.  The ridge is forecast to strengthen on Friday and it will steer Sergio more toward the west when that happens.  On its expected track Hurricane Sergio will move gradually farther away from Baja California.