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.