Powerful Hurricane Irma move north of the Dominican Republic on its approach to the Bahamas on Thursday morning. Hurricane Watches were issued for south Florida because of the potential impact of Hurricane Irma. At 11:00 a.m. EDT on Thursday the center of Hurricane Irma was located at latitude 20.4°N and longitude 69.7°W which put it about 120 miles (190 km) southeast of Grand Turk Island and about 785 miles (1265 km) east-southeast of Miami, Florida. The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 200 m.p.h. (320 km/h). The minimum surface pressure was 921 mb.
Hurricane Warnings were in effect for the portion of the coast from Cabo Engano, Dominican Republic to Le Mole St. Nicholas, Haiti, the Turks and Caicos, the southeastern Bahamas including the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana and the Ragged Islands, the central Bahamas including Cat Island, the Exumas, Long Island, Rum Cay and San Salvador, the northwestern Bahamas including the Abacos, Andros Island, Berry Island, Bimini, Eleuthera, Grand Bahama Island and New Providence.
A Hurricane Watch was in effect for the portion of the coast from Jupiter Inlet to Bonita Beach, Florida including the Florida Keys and Lake Okeechobee and from Matanzas province to Guantanamo province in Cuba.
A Tropical Storm Warning is in effect for the portion of the coast from Cabo Engano, Dominican Republic to the southern border with Haiti, from Le Mole St. Nicholas to Port Au Prince, Haiti and for the Cuban provinces of Guantanamo, Holguin and Las Tunas.
Hurricane Irma remains a large and dangerous hurricane. Irma weakened slightly on Thursday morning, but it still was a Category 5 hurricane on the Saffir-Simpson Scale. Irma has a large circular eye at the center of circulation. The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms. Winds to hurricane force extend out about 60 miles (95 km) from the center. Winds to tropical storm force extend out about 185 miles (305 km) from the center.
The Hurricane Intensity Index (HII) for Hurricane Irma is 40.4. The Hurricane Size Index (HSI) is 19.2 and the Hurricane Wind Intensity Size Index (HWISI) is 59.6. Those indices indicate that Hurricane Irma is capable of causing widespread catastrophic damage.
Hurricane Irma will remain in a favorable environment for the next several days. Irma will move over water where the Sea Surface Temperature is near 30°C. The upper level winds will be weak and there will be little vertical wind shear during the next 24 to 36 hours. When Irma gets farther north it will be near the southern end of a large upper level trough over the eastern U.S. The trough will produce southeasterly winds which will increase the shear somewhat. Hurricane Irma will remain a large dangerous hurricane.
Hurricane Irma is moving around the western end of a subtropical high over the Atlantic Ocean. The high is steering Irma toward the west-northwest and that general motion is expected to continue for another 36 to 48 hours. The effects of the upper level trough are expected to turn Irma toward the north during the weekend. On its anticipated track Hurricane Irma will reach the Turks and Caicos on Thursday night. Irma will move across the southeastern Bahamas on Friday and it could be north of Cuba by Saturday morning. Hurricane Irma could reach southern Florida by Sunday morning.
Hurricane Irma is capable of causing widespread catastrophic damage. Irma will generate storm surges as high as 19 feet (6 meters) when it passes over the Bahamas. Irma will cause widespread wind damage and locally heavy rain could cause flash floods.
The destructive core of Hurricane Irma moved over Barbuda, St. Barthelemy and St. Martin. There are reports of widespread damage on those islands. Other nearby islands my have also suffered significant damage.
Hurricane Jose is following in the wake of Hurricane Irma and Watches have been issued for some of the northern Leeward Islands. At 11:00 a.m. EDT on Thursday the center of Hurricane Jose was located at latitude 14.9°N and longitude 50.6°W which put it about 715 miles (1155 km) east of the Leeward Islands. Jose was moving toward the west-northwest at 18 m.p.h. (30 km/h). The maximum sustained wind speed was 90 m.p.h. (150 km/h) and there were wind gusts to 105 m.p.h. (170 km/h). The minimum surface pressure was 986 mb.
Hurricane Watches have been issued for Antigua and Barbuda. Tropical Storm Watches have been issued for Anguilla, Montserrat, St. Kitts and Nevis.
Hurricane Jose is moving through a favorable environment of warm Sea Surface Temperatures and little vertical wind shear. Hurricane Jose is forecast to intensify into a major hurricane. The same subtropical high steering Hurricane Irma is also steering Hurricane Jose. On its anticipated track Hurricane Jose could reach the northern Leeward Islands on Saturday. It could be a major hurricane at that time. If Hurricane Jose moves over some of the same places hit by Hurricane Irma it will serious impede efforts to recover from Irma.
Hurricane Katia is threatening parts of Mexico. At 11:00 a.m. EDT on Thursday the center of Hurricane Katia was located at latitude 21.6°N and longitude 94.6°W which put it about 215 miles (345 km) east of Tampico, Mexico. Katia was stationary. the maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (155km/h) The minimum surface pressure was 980 mb.
A Hurricane Warning is in effect for the portion of the coast from Cabo Rojo to Laguna Verde, Mexico.