Tag Archives: Turks and Caicos

Hurricane Fiona Drops Heavy Rain on Puerto Rico

Hurricane Fiona dropped heavy rain on Puerto Rico on Sunday and there were numerous reports of floods. At 11:00 p.m. EDT on Sunday the center of Hurricane Fiona was located at latitude 18.0°N and longitude 68.1°W which put it about 45 miles (75 km) south-southeast of Punta Cana, Dominican Republic. Fiona was moving toward the west-northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 982 mb.

A Hurricane Warning was in effect for Puerto Rico, Culebra and Vieques. A Hurricane Warning was also in effect for the portion of the coast from Cabo Caucedo to Cabo Frances Viejo, Domincan Republic. A Hurricane Warning was in effect for the Turks and Caicos. A Hurricane Watch was also in effect for the portion of the coast from Cabo Frances Viejo to Puerto Plata, Dominican Republic. Tropical Storm Warnings were in effect for the portion of the coast from Cabo Frances Viejo to Puerto Plata, Dominican Republic. Tropical Storm Warnings were also in effect for the Southeastern Bahamas including the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana and the Ragged Islands. A Tropical Storm Watch was in effect for the portion of the coast from Cabo Caucedo to Barahona, Dominican Republic.

The eye of Hurricane Fiona was over the Mona Passage between Puerto Rico and the Dominican Republic on Sunday night. The eye passed over the southwestern tip of Puerto Rico on Sunday afternoon. Heavy rain fell over much of Puerto Rico and there were many reports of flash floods. There were also reports of wind damage in parts of Puerto Rico and electricity was unavailable in most places.

Hurricane Fiona was strengthening gradually on Sunday night. An eye with a diameter of 12 miles (19 km) was at the center of Fiona. 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 Fiona. Storms near the core generated upper level divergence that pumped mass away from the hurricane. Winds to hurricane force extended out 30 miles (50 km) from the center of Fiona. Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation.

Hurricane Fiona will move through an environment mostly favorable for intensification during the next 48 hours. Fiona will move over water where the Sea Surface Temperatures are near 29˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. The center of Hurricane Fiona could pass over eastern Dominican Republic on Monday. Since some of the circulation around Hurricane Fiona will pass over land, that could cause Fiona to weaken when the center is near land. Fiona will be in an environment very favorable for intensification when it moves north of the Dominican Republic. It could rapidly intensify to a major hurricane early next week.

Hurricane Fiona will move around the western side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Fiona toward the northwest during the next 24 hours. On its anticipated track the center of Hurricane Fiona could make landfall in the eastern Dominican Republic near Punta Cana on Monday morning. Bands in the eastern side of Fiona’s circulation will continue to drop locally heavy rain on Puerto Rico on Monday. Hurricane Fiona will also bring strong winds and locally heavy rain to the eastern part of the Dominican Republic early on Monday.

Fiona Intensifies to a Hurricane South of Puerto Rico

Former Tropical Storm Fiona intensified to a hurricane south of Puerto Rico on Sunday morning. At 11:00 a.m. EDT on Sunday the center of Hurricane Fiona was located at latitude 17.3°N and longitude 66.5°W which put it about 50 miles (80 km) south of Ponce, Puerto Rico. Fiona was moving toward the west-northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (145 km/h). The minimum surface pressure was 987 mb.

A Hurricane Warning was in effect for Puerto Rico, Culebra and Vieques. A Hurricane Warning was also in effect for the portion of the coast from Cabo Caucedo to Cabo Frances Viejo, Domincan Republic. A Hurricane Watch was also in effect for the portion of the coast from Cabo Frances Viejo to Puerto Plata, Dominican Republic. Tropical Storm Warnings were in effect for the U.S. Virgin Islands, the British Virgin Islands, and the portion of the coast from Cabo Frances Viejo to Puerto Plata, Dominican Republic. A Tropical Storm Watch was in effect for the portion of the coast from Cabo Caucedo to Barahona, Dominican Republic. Tropical Storm Watches were in effect for the Turks and Caicos, and for the Southeastern Bahamas including the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana and the Ragged Islands.

Former Tropical Storm Fiona strengthened to a hurricane over the Caribbean Sea south of Puerto Rico. The inner end of a rainband wrapped around the northern side of the center of Hurricane Fiona. A partial eyewall surrounded the northern half of the center of Fiona’s circulation. The partial eyewall was over Ponce, Puerto Rico. Bands of showers and thunderstorms were revolving around the core of Hurricane Fiona. Storms near the core generated upper level divergence that pumped mass away from the hurricane. Winds to hurricane force extended out 30 miles (50 km) in the northeastern quadrant of Fiona’s circulation. Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation.

Hurricane Fiona will move through an environment mostly favorable for intensification during the next 36 hours. Fiona will move over water where the Sea Surface Temperatures are near 29˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. The center of Hurricane Fiona could pass over southwestern Puerto Rico during the next few hours. Fiona will move near the eastern part of the Dominican Republic on Monday. Since some of the circulation around Hurricane Fiona will pass over land during the next 36 hours, that could cause Fiona to weaken when the center is over or near land.

Hurricane Fiona will move around the western side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Fiona toward the northwest during the next 24 hours. On its anticipated track the center of Hurricane Fiona will be near the southwestern part of Puerto Rico by Sunday evening. Bands in the eastern and northern sides of Fiona’s circulation will bring strong winds and locally heavy rain to Puerto Rico, the U.S. Virgin Islands and the British Virgin Islands on Sunday. Hurricane Fiona could begin to affect the eastern part of the Dominican Republic during Sunday night.

Tropical Storm Fred Makes Landfall in Dominican Republic

Tropical Storm Fred made landfall on the coast of the Dominican Republic on Wednesday afternoon. At 2:00 p.m. EDT on Wednesday the center of Tropical Storm Fred was located at latitude 18.5°N and longitude 70.1°W which put it about 30 miles (50 km) west of Santo Domingo, Dominican Republic. Fred was moving toward the west-northwest at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1006 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Punta Palenque, Dominican Republic to the northern border with Haiti. A Tropical Storm Watch was in effect for the portion of the coast from Gonaives, Haiti to the northern border with the Dominican Republic. Tropical Storm Watches were in effect for the Southeastern Bahamas and the Turks and Caicos. Tropical Storm Watches were also in effect for the Cuban provinces of Ciego de Avila, Camaguey, Las Tunas, Holguin, Granma, Santiago de Cuba and Guantanamo.

The center of Tropical Storm Fred made landfall on the south coast of the Dominican Republic west of Santo Domingo on Wednesday afternoon. Fred became better organized and a little stronger prior to making landfall. A band of thunderstorms wrapped around the eastern and northern sides of the center of Tropical Storm Fred. Storms near the center generated upper level divergence that pumped mass away from the tropical storm and the surface pressure decreased slightly. The strongest winds were occurring in the eastern half of Tropical Storm Fred. At the time of landfall winds to tropical storm force extended out 60 miles (95 km) from the center of Fred’s circulation.

Tropical Storm Fred will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high will steer Fred toward the west-northwest during the next several days. On its anticipate track Tropical Storm Fred will move across the western part of the Dominican Republic and northern Haiti during the next 24 hours. Fred will drop locally heavy rain and flash floods could occur in some locations.

Mountains in the Dominican Republic and Haiti will significantly disrupt the low level circulation of Tropical Storm Fred. Fred is likely to weaken to a tropical depression during the next 12 hours. The circulation of Tropical Storm Fred in the middle troposphere could survive passage over those mountains. The center of Tropical Storm Fred will move northwest of Haiti on Thursday. The Sea Surface Temperatures of the water northwest of Haiti are near 29°C. If the middle level circulation of Fred survives, it could spin up a new low level center of circulation when it moves back over the warm water. An upper level low near Florida will produce westerly winds that will blow toward the top of Fred’s circulation. Those winds will cause vertical wind shear and they will inhibit re-intensification of Tropical Storm Fred. If the center of Fred remains north of Cuba, it could strengthen back to a tropical storm. Fred could approach the Florida Keys and South Florida on Friday. It could move over the Gulf of Mexico during the weekend.

Tropical Storm Fred Passes South of Puerto Rico

Tropical Storm Fred was passing south of Puerto Rico on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Fred was located at latitude 17.6°N and longitude 66.8°W which put it about 45 miles (75 km) south-southwest of Ponce, Puerto Rico. Fred was moving toward the west at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1009 mb.

Tropical Storm Warnings were in effect for Puerto Rico including Culebra and Vieques and the U.S. Virgin Islands. A Tropical Storm Warning was also in effect for the portion of the coast from Punta Palenque to Cabo Frances Viejo, Dominican Republic. A Tropical Storm Watch was in effect for the portion of the coast from Cabo Frances Viejo to the northern border with Haiti. A Tropical Storm Watch was in effect for the portion of the coast from Gonaives, Haiti to the northern border with the Dominican Republic. Tropical Storm Watches were also in effect for the Southeastern Bahamas and the Turks and Caicos.

A reconnaissance plane was able to identify a low level center of circulation in a low pressure system previously designated at Potential Tropical Cyclone Six on Tuesday evening and the National Hurricane Center upgraded the system to Tropical Storm Fred. The circulation around Tropical Storm Fred was still organizing. The low level center was about 45 miles (75 km) to the north of the center of circulation in the middle levels. The circulation in the middle levels was moving closer to the low level center. The strongest thunderstorms were occurring on the southern side of the low level center and near the center in the middle levels. Winds to tropical storm force extended out 45 miles (75 km) from the center in the northeastern quadrant of Fred. Winds in the other parts of the circulation were blowing at less than tropical storm force.

Tropical Storm Fred will move through an environment favorable for intensification during the next 12 hours. Fred will move over water where the Sea Surface Temperatures are near 28°C. It will be under a small upper level ridge. The upper level winds in the ridge are weak and there will be little vertical wind shear. Tropical Storm Fred is likely to strengthen during the next 12 hours. The center of Fred will be near the eastern part of the Dominican Republic in about 12 hours. Tropical Storm Fred is likely to weaken on Wednesday while the center is near Hispaniola.

Tropical Storm Fred will move of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Fred toward the west-northwest during the next several days. On its anticipated track Tropical Storm Fred will approach the eastern Dominican Republic in 12 hours. Fred could be over the northern coast of Hispaniola on Wednesday night. Bands in the northern side of Tropical Storm Fred will produce gusty winds and locally heavy rain over Puerto Rico on Tuesday night. Fred could drop heavy rain on parts of the Dominican Republic and Haiti on Wednesday. Heavy rain could cause flash floods in some locations.

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.

Isaias Rapidly Intensifies into a Hurricane Southeast of the Bahamas

Former Tropical Storm Isaias rapidly intensified into a hurricane southeast of the Bahamas on Thursday night.  At 11:40 p.m. EDT on Thursday the center of Hurricane Isaias was located at latitude 20.3°N and longitude 72.1°W which put it about 70 miles (110 km) east-southeast of Great Inagua.  Isaias was moving toward the northwest at 18 m.p.h. (30 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 995 mb.

Hurricane Warnings were issued for all of the Bahamas including the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana, the Ragged Islands, Cat Island, the Exumas, Long Island, Rum Cay, San Salvador, Andros Island, New Providence, Eleuthera, the Abacos, the Berry Islands, Grand Bahama Island and Bimini. Tropical Storm Warnings were in effect for the entire coast of the Dominican Republic, Le Mole St. Nicholas, Haiti to the northern border with the Dominican Republic, the Turks and Caicos.  A Tropical Storm Watch was in effect for the portion of the coast from Ocean Reef to Sebastian Inlet, Florida.

A reconnaissance plane sampling former Tropical Storm Isaias on Thursday night found winds to hurricane force and a decrease in surface pressure.  The core of Hurricane Isaias organized quickly after it moved over the warm water north of the Dominican Republic.  A band of strong thunderstorms wrapped around the western side of the center of circulation.  Winds to hurricane force extended out about 30 miles to the northeast of the center of circulation.  Winds to tropical storm force extended out 240 miles (390 km) to the north and east of Isaias in the parts of the circulation that were over water.  Thunderstorms near the center of circulations were generating upper level divergence which pumped mass away from the tropical storm and allowed the pressure to decrease.   Brands of thunderstorms were wrapping around the eastern and northern sides of the circulation.

Hurricane Isaias will move through an environment favorable for intensification during the next 36 hours.  Isaias 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 Isaias will strengthen on Friday and it could intensify more rapidly once an inner core consolidates.  Isaias could intensify into a major hurricane while it moves over the Bahamas.

Hurricane Isaias will move around the western end of a subtropical high pressure system over the North Atlantic Ocean.  The high will steer Isaias toward the northwest during the next 36 hours.  It will turn the hurricane more toward the north on the weekend when Isaias reaches the western end of the high pressure system. On its anticipated track Hurricane Isaias will move over the Southeastern Bahamas on Friday morning.  Isaias will move over the Central Bahamas later on Friday and it could approach southeast Florida on Saturday.  Hurricane Isaias could approach the coast of the Carolinas on Monday.  Hurricane Isaias will bring strong winds and locally heavy rain to the Turks and Caicos and the Bahamas.  Heavy rain could cause flash floods.  Hurricane Isaias will also generate a dangerous storm surge in the Bahamas.

Tropical Storm Isaias Reorganizes North of Dominican Republic, Watch Issued for South Florida

The circulation around Tropical Storm Isaias reorganized near the northern coast of the Dominican Republic on Thursday afternoon and Tropical Storm Watches were issued for part of the coast of southeast Florida.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Isaias was located at latitude 19.5°N and longitude 70.6°W which put it about 25 miles (40 km) southeast of Puerto Plata, Dominican Republic.  Isaias was moving toward the 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 999 mb.

Tropical Storm Warnings were in effect for the entire coast of the Dominican Republic, Le Mole St. Nicholas, Haiti to the northern border with the Dominican Republic, the Turks and Caicos, the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana, the Ragged Islands, Cat Island, the Exumas, Long Island, Rum Cay, San Salvador, Andros Island, New Providence, Eleuthera, the Abacos, the Berry Islands, Grand Bahama Island and Bimini.  A Tropical Storm Watch was in effect for the portion of the coast from Ocean Reef to Sebastian Inlet, Florida.

The low level center of Tropical Storm Isaias moved across the eastern part of the Dominican Republic on Thursday.  The middle and upper parts of Isaias skirted along the east coast of Hispaniola.  The various levels of Tropical Storm Isaias appeared to be reconsolidating near the northern coast of the Dominican Republic just to the east of Puerto Plata.  New thunderstorms were forming near the reorganizing center of Isaias.  Those storms were generating upper level divergence which pumped mass away from the tropical storm and allowed the pressure to decrease.  Brands of thunderstorms were wrapping around the eastern and northern sides of the circulation.  The strongest winds were occurring in the portions of those bands over water.  The circulation around Tropical Storm Isaias tightened up on Thursday.  Winds to tropical storm force extended out 240 miles (390 km) to the north and east of Isaias in the parts of the circulation that were over water.

Tropical Storm Isaias will move through an environment favorable for intensification once it moves past Hispaniola.  Isaias 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.  Tropical Storm Isaias will intensify when it moves north of Hispaniola and it could intensify rapidly once an inner core consolidates.  Isaias could intensify to a hurricane on Friday and it could strengthen into a major hurricane during the weekend.

Tropical Storm Isaias will move around the western end of a subtropical high pressure system over the North Atlantic Ocean.  The high will steer Isaias toward the northwest during the next 36 hours.  It will turn the tropical storm more toward the north on the weekend when Isaias reaches the western end of the high pressure system.  On its anticipated track Tropical Storm Isaias will move over the Turks and Caicos by Friday morning.  Isaias will move over the the Bahamas on Friday and it could approach southeast Florida on Saturday.  Tropical Storm Isaias could approach the coast of the Carolinas on Monday.  Tropical Storm Isaias will bring gusty winds and locally heavy rain to the Turks and Caicos and the Bahamas.  Heavy rain could cause flash floods.

Tropical Storm Isaias Drops Heavy Rain on Puerto Rico

Tropical Storm Isaias dropped heavy rain on Puerto Rico on Thursday.  At 8:00 a.m. EDT on Thursday the center of Tropical Storm Isaias was located at latitude 17.6°N and longitude 68.5°w which put it about 105 miles (165 km) east- southeast of Santo Domingo, Dominican Republic.  The center was about 80 miles (130 km) south of Cabo Engano.  Isaias was moving toward the 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 1003 mb.

Tropical Storm Warnings were in effect for Puerto Rico, Culebra, Vieques, the U.S. Virgin Islands, the British Virgin Islands,  the entire coast of the Dominican Republic, Le Mole St. Nicholas, Haiti to the northern border with the Dominican Republic, the Turks and Caicos, the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana, the Ragged Islands, Cat Island, the Exumas, Long Island, Rum Cay and San Salvador.  Tropical Storm Watches were in effect for Andros Island, New Providence, Eleuthera, the Abacos, the Berry Islands, Grand Bahama Island and Bimini.

Bands on the eastern side of Tropical Storm Isaias were dropping heavy rain over parts of Puerto Rico on Thursday morning.  Flash Flood Warnings were in effect for parts of the island.  Isaias was also causing winds to tropical storm force in parts in Puerto Rico.  A station at Yabucoa Tanque de Agua reported a sustained wind speed of 46 m.p.h. (74 km/h) and a wind gust to 56 m.p.h. (91 km/h).  A station at Las Mareas reported a sustained wind speed of 3 m.p.h. (69 km/h) and a wind gust of 54 m.p.h. (87 km/h).

The circulation around Tropical Storm Isaias exhibited much more organization on Thursday morning, although the mid-level center did appear to be displaced to the north of the low level center.  There was a center of circulation but the distribution of thunderstorms was asymmetrical.  Most of the stronger thunderstorms were occurring in bands in the eastern side of Tropical Storm Isaias.  Storms near the center of circulation were generating upper level divergence which was pumping mass away from the tropical storm.  Bands in the western half of Isaias consisted primarily of showers and lower clouds.  Northerly winds on that side of the circulation were sinking over the southern part  of Hispaniola and that could have been suppressing the development of thunderstorms in that region.  The circulation around Tropical Storm Isaias was very still very large.  Winds to tropical storm force extended out 415 miles (665 km) on the northern side of Isaias.

Tropical Storm Isaias could weaken when the low level center of circulation moves across the eastern part of the Dominican Republic.  The low level circulation will be disrupted by the terrain but it looks like Isaias will pass east of the tallest mountains on Hispaniola.  The mid-level center of Tropical Storm Isaias appears to be passing very close to the eastern end of Hispaniola.  The middle and upper portions of the circulation are likely to remain intact and a new low level circulation could form north of Hispaniola.  Tropical Storm Isaias will move through an environment favorable for intensification once it moves past Hispaniola.  Isaias 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.  Tropical Storm Isaias is likely to intensify when it moves north of Hispaniola and it could intensify rapidly once a new low level center of circulation develops.

Tropical Storm Isaias will move around the western end of a subtropical high pressure system over the North Atlantic Ocean.  The high will steer Isaias toward the northwest during the next 48 hours.  it will turn the tropical storm more toward the north on the weekend when Isaias reaches the western end of the high pressure system.  On its anticipated track Tropical Storm Isaias will move across the eastern part of the Dominican Republic today.  Isaias will move over the Bahamas on Friday and it could approach southeast Florida on Saturday.  Tropical Storm Isaias will bring gusty winds and locally heavy rain to Puerto Rico, Hispaniola and the Bahamas.  Flash floods could occur.

Tropical Storm Isaias Develops South of Puerto Rico

Tropical Storm Isaias developed south of Puerto Rico on Wednesday night.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Isaias was located at latitude 15.8°N and longitude 67.0°W which put it about 155 miles (250 km) south of Ponce, Puerto Rico.  Isaias was moving toward the west-northwest at 20 m.p.h. (32 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 Puerto Rico, Culebra, Vieques, the U.S. Virgin Islands, the British Virgin Islands, St. Martin, St. Barthelemy, Saba, St. Eustatius, St. Maarten, the entire coast of the Dominican Republic, Le Mole St. Nicholas, Haiti to the northern border with the Dominican Republic, the Turks and Caicos, the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana, the Ragged Islands, Cat Island, the Exumas, Long Island, Rum Cay and San Salvador.  Tropical Storm Watches were in effect for Andros Island, New Providence, Eleuthera, the Abacos, the Berry Islands, Grand Bahama Island and Bimini.

Data from a scatterometer onboard a satellite and observations from a buoy south of Puerto Rico indicated that a distinct center of circulation formed within a large low pressure system over the northeastern Caribbean Sea and the National Hurricane Center designated the system as Tropical Storm Isaias.  The center of circulation formed about 150 miles (240 km) south of Puerto Rico on Wednesday night.  More thunderstorms were developing near the newly formed center.  Many of those thunderstorms were southeast of the center.  Storms near the center were generating upper level divergence which pumped mass away from the tropical storm.  Bands of showers and thunderstorms were also located on the northern periphery  of the circulation and the strongest winds were occurring in those bands.  Winds to tropical storm force extended out 300 miles (485 km) to the northeast of the center of circulation.  Winds to tropical storm force also extended out 130 miles (215 km) to the northwest of the center.  The winds south of the center of Isaias were blowing at less than tropical storm force.

Tropical Storm Isaias will move through an environment favorable for intensification during the next 12 hours.  Isaias 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.  Tropical Storm Isaias will get better organized and strengthen during the first half of Thursday.  A portion of the circulation around Isaias will move over Hispaniola later on Thursday.  Mountains on that island will disrupt the circulation and Tropical Storm Isaias will weaken while the center moves over land.

Tropical Storm Isaias will move around the western end of a subtropical high pressure system over the North Atlantic Ocean.  The high will steer Isaias toward the west-northwest on Thursday.  On its anticipated track Tropical Storm Isaias will move across Hispaniola on Thursday.  Isaias will cause gusty winds and it will drop locally heavy rain when it moves over Hispaniola.  Heavy rain could cause flash floods.

Major Hurricane Maria Moves Slowly Toward the Turks and Caicos

Major Hurricane Maria moved slowly toward the Turks and Caicos on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Hurricane Maria was located at latitude 21.0°N and longitude 80.2°W which put it about 65 miles (110 km) east-southeast of the Turks and Caicos.  Maria was moving toward the northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 955 mb.

Hurricane Warnings were in effect for the Turks and Caicos, the Southeastern Bahamas and the portion of the coast from Cabo Engano to Puerto Plata, Dominican Republic.  Tropical Storm Warnings are in effect for portion of the coast from Puerto Plata, Dominican Republic to the northern border with Haiti.  Tropical Storm Watches are in effect for the Central Bahamas.

The core of Hurricane Maria reorganized on Thursday as the center moved over the warm water north of the Dominican Republic.  A large eye formed at the center of circulation.  The eye had a diameter of 40 miles (64 km).  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.   Several bands of showers and thunderstorms were revolving around the core of Hurricane Maria.  Crossing over Puerto Rico and an eyewall replacement cycle produced a larger circulation.  Winds to hurricane force extended out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Hurricane Maria will move through an environment favorable for strong hurricanes.  Maria will move over water where the Sea Surface Temperatures are near 29°C.  Hurricane Maria will remain in an area where the upper level winds are weak and there is likely to be little vertical wind shear for at least one more day.  The outer portion of the southern half of Hurricane Maria’s circulation is still passing over the Dominican Republic.   Additional friction in the part of the circulation passing over land could reduce the amount of intensification that occurs.  Hurricane Maria is likely to strengthen on Friday and it could reach Category 4 on the Saffir-Simpson Scale.

Hurricane Maria is nearing the western end of the subtropical high pressure system which is steering the hurricane toward the northwest.  Maria is entering an area where the steering currents are weaker and the motion of the hurricane slowed on Thursday night.  The numerical models are still forecasting that Hurricane Maria will turn north on Friday when it rounds the western end of the high pressure system.  Hurricane Maria is moving a little farther west than has been forecast and that trend could continue on Friday.  If Hurricane Maria does move farther west than anticipated, then the core of Maria could come very close to the Turks and Caicos and parts of the Southeastern Bahamas.

Even if the center of Hurricane Maria does not pass directly over the Turks and Caicos and Southeastern Bahamas, bands of showers and thunderstorms will bring gusty winds and locally heavy rain.  Maria will also cause a storm surge on the coasts of those islands.  If the center of Maria passes directly over them, the hurricane is capable of causing major damage.  The southern part of Maria’s circulation is bringing heavy rain to parts of the Dominican Republic and there is the potential for flash floods.