Hurricane Matthew moved away from Cuba and across the Southeastern Bahamas on Wednesday. At 11:00 p.m. EDT on Wednesday the center of Hurricane Matthew was located at latitude 23.4°N and longitude 76.4°W which put it about 125 miles (205 km) south-southeast of Nassau, Bahamas and about 325 miles (525 km) southeast of West Palm Beach, Florida. Matthew was moving toward the northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (220 km/h). The minimum surface pressure was 961 mb. Hurricane Matthew was a Category 3 hurricane on the Saffir-Simpson Scale.
A Hurricane Warning is in effect for the portion of the coast from Golden Beach, Florida to Fernandina Beach including Lake Okeechobee. A Hurricane Watch has been issued for the portion of the coast of Florida from Fernandina Beach to Edisto Beach, South Carolina. A Tropical Storm Warning is in effect for the portion of the coast from Chokoloskee to Golden Beach, Florida and for the Florida Keys from Seven Mile Bridge eastward including Florida Bay. A Tropical Storm Watch has been issued for the portion of the coast from Chokoloskee, Florida to Suwanee River. Hurricane Warnings are also in effect for the Southeastern Bahamas including the Inaguas, Mayaguana, Acklins, Crooked Island, Long Cay, Ragged Island, and for the Central Bahamas including Long Island, Exuma, Rum Cay, San Salvador and Cat Island. A Hurricane Warning is in effect for the northwestern Bahamas including the Abacos, Andros Island, Berry Islands, Bimini, Eleuthera, Grand Bahama Island and New Providence.
Hurricane Matthew weakened after it passed over southwestern Haiti and the eastern end of Cuba. The structure of the eyewall deteriorated on Wednesday morning, when the core of Hurricane Matthew started to move north of Cuba. After a few hours over the warm water around the Bahamas, a circular eyewall began to reform around the center of circulation. The eyewall appeared to weaken for a time on Wednesday afternoon, but it then became much more well organized around a distinct eye appeared on Wednesday night. The loss of organization around the eye resulted in a decrease in the maximum sustained wind speed to 115 m.p.h. and an increase in the minimum surface pressure to 964 mb.
Hurricane Matthew appeared to be intensifying on Wednesday night. A reconnaissance aircraft observed a minimum surface pressure that was several millibars lower and the structure of the core of the hurricane was displaying more organization. Thunderstorms around the eye of Hurricane Matthew were beginning to generate stronger upper level divergence which was pumping mass out in all directions. The divergence was allowing the surface pressure to decrease as measured by the recon plane.
Hurricane Matthew is moving through a very favorable environment. It is moving over water where the Sea Surface Temperature is near 30°C. The upper level winds are light and there is little vertical wind shear. As the minimum pressure decrease, the pressure gradient force will accelerate the air faster and the wind speeds will increase. Hurricane Matthew could become a Category 4 hurricane on Thursday and there is a chance it could get near Category 5.
A ridge of high pressure is steering Matthew toward the northwest and that general motion is expected to continue on Thursday. The center of strong hurricanes sometimes wobble a bit from side to side in response to bursts of thunderstorms in the eyewall, but the general motion is likely to be toward the northwest. The center of Hurricane Matthew is passing just west of the Exumas in the Bahamas. Matthew is likely to pass near Nassau on New Providence and near Andros Island on Thursday morning.
On its anticipated track Hurricane Matthew could be very near the southeast coast of Florida by Thursday evening. Matthew could make landfall in the portion of the coast between Fort Lauderale and West Palm Beach or the center could stay just offshore. The center of Hurricane Matthew is forecast to move along the east coast of Florida on Friday. An upper level trough approaching from the west is expected to turn Hurricane Matthew toward the northeast on Friday night or Saturday. However, the timing and location of that turn is still uncertain. It could occur near the coast of Georgia and South Carolina or it could occur a little sooner and move the center of Matthew back over the Atlantic Ocean.
Hurricane Matthew poses a serious potential risk to the southeast coast of the U.S. The Hurricane Intensity Index (HII) is 20.6. The Hurricane Size Index (HSI) is 15.7 and the Hurricane Wind Intensity Size index (HWISI) is 36.3. Those indices indicate that Matthew will be capable of causing regional wind damage. Matthew could get bigger and stronger before it reaches Florida, which would increase the risk. If Matthew tracks along the coast or just inland, will bring hurricane force winds to the populated areas on the east coast of Florida. In addition, strong easterly winds north of the center of Hurricane Matthew will blow water toward the coast and create the potential for dangerous storm surges. Matthew will move slowly enough that locally heavy rain could fall and fresh water flooding could also create problems.