Tag Archives: Florida Keys

Major Hurricane Eta Makes Landfall in Nicaragua

Major Hurricane Eta made landfall on the coast of Nicaragua on Tuesday afternoon. At 4:00 p.m. EST on Tuesday the center of Hurricane Eta was located at latitude 13.8°N and longitude 83.5°W which put it about 15 miles (25 km) south-southwest of Puerto Cabezas, Nicaragua. Eta was moving toward the west at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 165 m.p.h. (265 km/h). The minimum surface pressure was 940 mb.

A Hurricane Warning was in effect for the portion of the coast from Sandy Bay Sirpi, Nicaragua to the Honduras/Nicaragua border. A Tropical Storm Warning was in effect for the portion of the coast from the Honduras/Nicaragua border to Punta Patuca, Honduras.

Hurricane Eta moved very slowly onto the coast of Nicaragua just to south of Puerto Cabezas on Tuesday afternoon. Concentric eyewalls developed around the center of Eta before it made landfall. The start of an eyewall replacement cycle caused the intensity of Hurricane Eta to remain relatively steady as it approached the coast of Nicaragua. An environment favorable for strong hurricanes allowed Eta to continue to be a major hurricane at the time of landfall.

Winds to hurricane force extended out 25 miles (40 km) from the center of Hurricane Eta at the time it made landfall. Winds to tropical storm force extended out 100 miles (160 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Eta was 28.3. The Hurricane Size Index (HSI) was 9.4 and the Hurricane Wind Intensity Size Index (HWISI) was 37.7.

Hurricane Eta was capable of causing significant wind damage. over northeastern Nicaragua. The northern eyewall which contained the strongest winds passed over Puerto Cabezas. Eta could also cause a storm surge of 15 to 18 feet (5 to 6 meters) along the coast near Puerto Cabezas. Hurricane Eta will weaken as it moves slowly inland over northern Nicaragua and the wind speeds will decrease quickly. Eta will drop very heavy rain over northern Nicaragua and Honduras. Some locations could receive 20 to 30 inches (50 to 75 cm). The heavy rain could cause catastrophic flash floods in parts of Nicaragua and Honduras.

Eta will move more toward the northwest on Wednesday and the circulation could emerge over the northwestern Caribbean Sea on Friday. There is a chance that Eta could strengthen back to a tropical storm if the circulation moves back over water. Eta could bring gusty winds and rain to the Florida Keys by Sunday.

Tropical Storm Paulette Causes Hurricane Warning for Bermuda

A likely intensification of Tropical Storm Paulette caused a Hurricane Warning to be issued for Bermuda on Saturday morning.  At 11:00 a.m. EDT on Saturday the center of Tropical Storm Paulette was located at latitude 27.5°N and longitude 57.2°W which put it about 565 miles (905 km) southeast of Bermuda.  Paulette was moving toward the northwest 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 987 mb.

A Hurricane Warning was in effect for Bermuda.

Tropical Storm Paulette was on the verge of strengthening into a hurricane on Saturday morning.  Microwave satellite imagery indicated that a small circular eye was forming at the center of Paulette.  A ring of strong thunderstorms was developing around the eye.  Bands of showers and thunderstorms were revolving around the core of Tropical Storm Paulette.  The stronger thunderstorms were in bands in the northern half of the circulation.  Bands in the southern half of Paulette consisted primarily of showers and lower clouds.   Winds to tropical storm force extended out 200 miles (320 km) on the northern side of Tropical Storm Paulette.  Winds to tropical storm force extended out 100 miles (160 km) on the southern side of the circulation.

Tropical Storm Paulette will move through an environment favorable for intensification.  Paulette will move over water where the Sea Surface Temperature is near 29°C.  It will move into an area that is northeast of an upper low north of Puerto Rico and west of an upper level ridge that is over the eastern Atlantic Ocean.  The upper low will produce southerly winds which will blow toward the top of Tropical Storm Paulette.  Those winds will cause moderate vertical wind shear and the shear will slow the rate of intensification.  In spite of the wind shear Paulette is likely to strengthen into a hurricane during the next 24 hours.

Tropical Storm Paulette will move around the western end of a subtropical high pressure system over the Atlantic.  The high will steer Paulette toward the northwest during the next 36 hours.  On its anticipated track Tropical Storm Paulette will approach Bermuda on Sunday night.  Paulette will almost certainly be a hurricane when it approaches Bermuda.

Elsewhere, Tropical Depression Nineteen was strengthening near Southwest Florida and Rene weakened to a tropical depression west of the Cabo Verde Islands.  At 11:00 a.m. EDT on Saturday the center of Tropical Depression Nineteen was located at latitude 25.6°N and longitude 81.5°W which put it about 40 miles (65 km) south-southeast of Naples, Florida.  The depression was moving toward the west at 9 m.p.h. (15 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 1004 mb.

A Tropical Storm Watch was in effect for the portion of the coasst from Ochlockonee River to the Okaloosa/Walton  County Line in Florida.

Tropical Depression Nineteen was dropping heavy rain over the Florida Keys on Saturday morning.  The depression is forecast to strengthen into a hurricane as it moves over the eastern Gulf of Mexico during the next 48 hours.  A Hurricane Watch is likely to be issued for the Northern Gulf Coast later today.

At 11:00 a.m. EDT on Saturday the center of Tropical Depression Rene was located at latitude 23.2°N and longitude 44.4°W which put it about 1415 miles (2275 km) west-northwest of teh Cabo Verde Islands.  Rene was moving toward the northwest at 13 m.p.h. (20 km/h).  Th 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.

Tropical Storm Laura Prompts Hurricane Watch for Northwest Gulf Coast

The potential threat from Tropical Storm Laura prompted the issuance of a Hurricane Watch for a portion of the northwest Gulf Coast on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Laura was located at latitude 21.7°N and longitude 82.2°W which put it about 40 miles (65 km) east of the Isle of Youth, Cuba.  Laura was moving toward the west-northwest at 20 m.p.h. (32 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 1001 mb.

A Hurricane Watch was issued for the portion of the coast from Port Bolivar, Texas to Morgan CIty, Louisiana.  A Tropical Storm Watch was issued for the portion of the coast from Morgan City to the Mouth of the Mississippi River.  A Tropical Storm Warning remained in effect for the Florida Keys from Craig Key to Key West and the Dry Tortugas.  Tropical Storm Warnings were also in effect for the Cuban provinces of Ciego de Avila, Sancti Spiritus, Villa Carla, Cienfuegos, Matanzas, Mayabeque, La Habana, Artemisa, Pinar del Rio and Isle of Youth.

The appearance of Tropical Storm Laura did not change much on Monday afternoon.  Many of the stronger thunderstorms were occurring in bands in the southern half of the circulation.  bands in the northern half of the circulation consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 175 miles (280 km) from the center on the eastern side of Laura.  Winds were blowing at less than tropical storm force in the western half of the circulation.

Tropical Storm Laura will move near Cuba for another 12 to 18 hours.  So, the flow of air across Cuba is likely to continue to disrupt the northern half of the circulation during the time period.  When Laura moves over the Gulf of Mexico on Tuesday , it will move into an environment favorable for intensification.  Tropical Storm Laura will move over water where the Sea Surface Temperature is near 30°C.  It will move into an area where the upper level winds will be weak and there will be little vertical wind shear.  Tropical Storm Laura will intensify into a hurricane over the Gulf of Mexico and it could strengthen into a major hurricane.

Tropical Storm Laura will move around the western end of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Laura toward the west-northwest during the next 12 to 24hours.  Laura will move more toward the north when it reaches the western end of the high.  On its anticipated track Tropical Storm Laura could make landfall on the northwest coast of the Gulf of Mexico on Wednesday night.  Laura could be a major hurricane when it makes landfall.

Elsewhere,  the center of Tropical Storm Marco was very close to the Mouth of the Mississippi River.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Marco was located at latitude 29.0°N and longitude 88.9°W which put it about 15 miles (25 km) east-southeast of the Mouth of the Mississippi River.  Marco was moving toward the northwest at 7 m.p.h. (11 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 1008 mb.  All coastal watches and warnings for Tropical Storm Marco have been discontinued.

Tropical Storm Marco Weakens Near Louisiana

Tropical Storm Marco weakened near Louisiana on Monday morning.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Marco was located at latitude 28.5°N and longitude 88.5°W which put it about 55 miles (90 km) southeast of the Mouth of the Mississippi River.  Marco was moving toward the north-northwest at 8 m.p.h. (13 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 1006 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Morgan City, Louisiana to the Mississippi/Alabama border including New Orleans, Lake Pontchartrain and Lake Maurepas.

An upper level trough over Texas produced strong southwesterly winds which sheared the top off of Tropical Storm Marco on Monday morning.  Stronger thunderstorms were confined to a few bands northeast of the center of circulation.  Bands around the center and in other parts of Marco consisted of showers and lower clouds.  Winds to tropical storm force were only occurring in the thunderstorms northeast of the center.

Since the wind shear is expected to continue, the circulation around Tropical Storm Marco is expected to spin down.  As Marco weakens it will be steer more by the winds in the lower atmosphere.  A subtropical high pressure system over the Atlantic Ocean is expected to expand to the west during the next several days.  The high will turn the low level circulation of Tropical Storm Marco more toward the west.  On its anticipated track Tropical Storm Marco will make landfall over southeastern Louisiana on Monday night.  Marco will bring gusty winds and some rain, but its impact is likely to be minor.

Elsewhere, Tropical Storm Laura was moving near the south coast of Cuba.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Laura was located at latitude 21.2°N and longitude 80.6°W which put it about 65 miles east-southeast of Cayo Largo, Cuba.  Laura was moving toward the west-northwest at 20 m.p.h. (32 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 1002 mb.

Tropical Storm Warnings were in effect for the Florida Keys from Craig Key to Key West and for the Dry Tortugas.  Tropical Storm Warnings were in effect for Little Cayman and Cayman Brac.  Tropical Storm Warnings were also in effect for the Cuban provinces of Camaguey, Las Tunas, Ciego De Avila, Sancti Spiritus, Villa Clara, Cienfuegos, Matanzas, Mayabeque, La Habana, Artemisa, Pinar Del Rio and Isle of Youth.

The circulation around Tropical Storm Laura was not as well organized on Monday morning.  Passage of Hispaniola and eastern Cuba disrupted the northern half of the circulation.  The strongest thunderstorms were occurring in bands in the southern half of the circulation.  Bands in the northern half of the circulation consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 175 miles (280 km) on the eastern side of Laura.  The winds on the western side of the circulation were blowing at less than tropical storm force.

Tropical Storm Laura will move near the south coast of Cuba for another 18 hours.  Since nearly half the circulation will be blowing across Cuba, it will continue to disrupt the northern half of the tropical storm.  Laura will move over the Gulf of Mexico on Tuesday.  When Tropical Storm Laura reaches the Gulf, it will move into a very favorable environment.  Laura will move over water where the Sea Surface Temperature is near 30°C.  It will move into a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Laura will intensify into a hurricane over the Gulf of Mexico and it could rapidly strengthen into a major hurricane.  Laura is expected to move over the northwestern Gulf of Mexico on Wednesday.

Marco Strengthens to a Hurricane, Laura Drenches Hispaniola

Former Tropical Storm Marco strengthened into a hurricane on Sunday over the Gulf of Mexico while Tropical Storm Laura dropped drenching rain on Hispaniola.  At 2:00 p.m. EDT on Sunday the center of Hurricane Marco was located at latitude 25.3°N and longitude 87.4°W which put it about 280 miles (450 km) south-southeast of the Mouth of the Mississippi River.  Marco was moving toward the north-northwest at 14 m.p.h. (22 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 992 mb.

A Hurricane Warning was in effect for the portion of the coast from Morgan City, Louisiana to the Mouth of the Pearl River, Mississippi.  Hurricane Watches were in effect for the portion of the coast from Intracoastal City, Louisiana to Morgan City and for New Orleans, Lake Pontchartrain and Lake Maurepas.  A Tropical Storm Warning was in effect from the Mouth of the Pearl River to the Mississippi/Alabama border.  A Tropical Storm Watch was in effect for the portion of the coast from the Mississippi/Alabama border to the Alabama/Florida border.

Former Tropical Storm Marco strengthened into a hurricane on Sunday.  A small eye developed at the center of circulation.  A ring of thunderstorms surrounded eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Marco.  Storms near the core generated upper level divergence which pumped mass away to the northeast of the hurricane.

The circulation around Hurricane Marco was small.  Winds to hurricane force extended out 15 miles (25 km) from the center of circulation.  Winds to tropical storm force extended out 70 miles (110 km) from the center.

Hurricane Marco will move through an environment somewhat favorable for intensification during the next 18 hours.  Marco will move over water where the Sea Surface Temperature is near 30°C.  An upper level trough over the northwestern Gulf of Mexico will produce southwesterly winds which will blow toward the top of Hurricane Marco.  Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent Marco from strengthening during the next 18 hours.

The upper level trough and a subtropical high pressure system over the Atlantic Ocean will steer Hurricane Marco toward the north-northwest during the next day or so.  On its anticipated track Hurricane Marco will approach southeast Louisiana on Monday.  Marco will bring gusty winds and drop locally heavy rain over southeastern Louisiana and southern Mississippi.

Elsewhere, Tropical Storm Laura dropped heavy rain on the Dominican Republic and Haiti.  There were reports of flash floods.  At 2:00 pm. EDT on Sunday the center of Tropical Storm Laura was located at latitude 19.4°N and longitude 74.3°W which put it about 80 miles (130 km) southeast of Guantanamo, Cuba.  Laura was moving toward the west-northwest at 21 m.p.h. (33 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 1004 mb.

Tropical Storm Warnings were in effect for the portion of the northern coast of the Dominican Republic from Samana to the border with Haiti and for the entire coast of Haiti.  Tropical Storm Warnings were in effect for the Turks and Caicos, the Acklins, Crooked Island, Long Cay, the Inaguas, and the Ragged Islands.  Tropical Storm Warnings were also in effect for the Cuban provinces of Las Tunas, Holguin, Guantanamo, Santiago de Cuba, Granma, Ciego de Avila, Sancti Spiritus, Villa Carla, Cienfuegos, Matanzas, Mayabeque, La Habana, Artemisa, Pinar del Rio and the Isle of Youth.  A Tropical Storm Watch was in effect for the Florida Keys to the Isle of Youth.  Tropical Storm Watches were also in effect for the Central Bahamas and Andros Island.

Tropical Storm Marco Strengthens, Hurricane Watch for New Orleans

Tropical Storm Marco strengthened on Saturday and a Hurricane Watch was issued for a portion of the central Gulf Coast.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Marco was located at latitude 21.9°N and longitude 68.1°W which put it about 50 miles (80 km) west of the western tip of Cuba.  Marco was moving toward the north-northwest at 13 m.p.h. (20 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 992 mb.

A Hurricane Watch was issued for the portion of the coast from Intracoastal City, Louisiana to the Mississippi/Alabama border including Lake Pontchartrain, Lake Maurepas and New Orleans.  A Tropical Storm Watch was in effect for the portion of the coast from the Mississippi/Alabama border to the Alabama/Florida border.  A Tropical Storm Warning was in effect for the Cuban province of Pinar del Rio.

Tropical Storm Marco exhibited much better organization on Saturday.  Weather radar on a reconnaissance plane and from Cuba as well as visible satellite images indicated that a small eye developed at the center of Marco.  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 Tropical Storm Marco.  Storms near the core were generating upper level divergence which was pumping away to the north of the tropical storm.  The circulation around Marco was small.  Winds to tropical storm force extended out 100 miles (160 km) to the east of the center of circulation.  Winds to tropical storm force only extended out 50 miles (80 km) on the western side of the tropical storm.

Tropical Storm Marco will move through an environment favorable for intensification during the nextt 24 hours.  Marco will move over water where the Sea Surface Temperature is near 30°C.  It will move east of an upper level trough over the Gulf of Mexico.  The trough will produce southwesterly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, but the shear is not likely to be enough to prevent intensification.  Tropical Storm Marco is likely to intensify into a hurricane during the next 24 hours.  Since he circulation around Marco is small, the tropical storm could strengthen or weaken quickly if the environment changes.

The upper level trough and a subtropical high pressure system over the Atlantic Ocean will steer Tropical Storm Marco toward the north-northwest during the next 36 to 48 hours.  On its anticipated track Marco could approach southeastern Louisiana by Monday afternoon.  Marco could be a hurricane when it approaches the coast.

Elsewhere, Tropical Storm Laura dropped heavy rain over Puerto Rico and it prompted the issuance of a Tropical Storm Watch for the Florida Keys.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Laura was located at latitude 18.0°N and longitude 68.1°W which put it about 125 miles (200 km) east-southeast of Santo Domingo, Dominican Republic.  Laura was moving toward the west at 18 m.p.h. (30 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 1004 mb.

Tropical Storm Warnings were in effect for the U.S. Virgin Islands, Puerto Rico, Vieques and Culebra.  A Tropical Storm Warning was in effect for the northern coast of Hispaniola from Le Mole St. Nicholas, Haiti to Cabo Engano, Dominican Republic.  Tropical Storm Warnings were in effect for the Turks and Caicos, the Acklins, Long Key, Crooked Island, the Inaguas, and the Ragged Islands.  A Tropical Storm Warning was also in effect for the Cuban provinces of Las Tunas, Holguin, Santiago de Cuba, Guantanamo and Granma.

A Tropical Storm Watch was issued for the Florida Keys from Ocean Reef to Key West.  Tropical Storm Watches were in effect for the Central Bahamas and for Andros Island.

Tropical Storm Marco is forecast to move over HIspaniola and the mountains there are likely to disrupt the circulation.

Disturbance South of Florida Keys

A disturbance south of the Florida Keys is currently designated at Invest 90L.  The disturbance could develop into a tropical or subtropical cyclone during the next few days.  At 8:00 p.m. EDT on Thursday the center of Invest 90L was located at latitude 23.9°N and longitude 81.2°W which put it about 55 miles (85 km) south of Marathon, Florida.  It was moving toward the east-northeast at 5 m.p.h. (8 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 1013 mb.

A small trough in the middle troposphere moved over a stationary front south of the Florida Keys on Thursday.  Satellite images and radar loops detected rotation in the middle troposphere.  There was a broad counterclockwise rotation south of the Keys and radar loops also revealed several small counterclockwise rotations within the broader mid-level circulation.  However, there did not appear to be a distinct center of circulation with lower pressure at the surface.

Invest 90L is forecast to move toward the northeast during the next several days.  It will move into an environment more favorable for development into a tropical or subtropical cyclone.  Invest 90L will move over water where the Sea Surface Temperature is near 27°C.  There will be an upper level trough over the eastern Gulf of Mexico, but a small upper level ridge will develop east of Florida.  The combination of the upper level trough and the upper ridge will produce a region of upper level divergence east of Florida.  The upper level divergence will pump mass away and the surface pressure will decrease in that area.  A surface low pressure system is likely to form on Friday or Saturday.  The National Hurricane Center is indicating that there is an 80% probability of the formation of a tropical or subtropical cyclone.  A reconnaissance plane is tentatively scheduled to investigate the system on Friday afternoon, if necessary.

Tropical Disturbance Brings Rain to Southeastern Bahamas

A tropical disturbance brought rain to the Southeastern Bahamas on Wednesday.  The disturbance was also designated at Invest 95L.  At 8:00 p.m. EDT on Wednesday the center of the tropical disturbance was located at latitude 21.8°N and longitude 74.0°W which put it about 30 miles (50 km) southeast of Acklins Island, Bahamas.  The disturbance was moving toward the west-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 gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1010 mb.

The circulation around the tropical disturbance was not well organized on Wednesday.  There were indications of cyclonic turning in the wind flow, but there were no reports of westerly winds at the surface.  The lack of westerly winds indicated that there probably was not a defined center of circulation at the surface.  There were some thunderstorms near the apparent middle of the tropical disturbance.  There was a larger cluster of thunderstorms east of the middle of the disturbance and a second cluster of thunderstorms northeast of the middle of the disturbance.

The tropical disturbance will be in an environment marginally favorable for the development of a tropical cyclone.  The disturbance will move over water where the Sea Surface Temperature is near 29°C.  A large upper level low over the eastern Gulf of Mexico is producing southerly winds which are blowing over the western half of the disturbance.  Those winds are producing moderate vertical wind shear.  There is another, smaller upper level low near Bermuda.  An small upper level ridge is developing between the two upper lows.  The winds are weaker in the ridge which is over the eastern half of the tropical disturbance.  It is possible that a center of circulation could develop in one of the clusters of thunderstorms east and northeast of the middle of the disturbance.  The National Hurricane Center is indicating that there is a 50% probability of development of a tropical cyclone during the next 48 hours and a 70% during the next five days.

The upper low over the Gulf of Mexico and the developing upper ridge are likely to combine to steer the disturbance toward the northwest during the next few days.  It is difficult to anticipate the  track until a distinct center of rotation forms.  If the center reforms east or northeast of the current middle of the disturbance, then that would affect the future track.  On the most probable track the disturbance would move across the southeastern and central Bahamas during the next several days.  It could approach southeast Florida or the Florida Keys on Friday night.  The disturbance could move into the eastern Gulf of Mexico during the weekend.  If the disturbance brings any significant rain to the northern Bahamas, that would hamper efforts to recover from the catastrophic damage caused by Hurricane Dorian.

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.