Hurricane Fiona intensified to Category 4 on the Saffir-Simpson Scale on Wednesday morning. At 8:00 a.m. EDT on Wednesday the center of Hurricane Fiona was located at latitude 24.2°N and longitude 71.7°W which put it about 700 miles (1125 km) southwest of Bermuda. Fiona was moving toward the north at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 130 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 937 mb.

A Hurricane Watch was issued for Bermuda. A Tropical Storm Warning was also in effect for Bermuda.

Hurricane Fiona continued to intensify over the warm Atlantic Ocean east of the Bahamas on Wednesday morning. A circular eye with a diameter of 30 miles (50 km) was present at the center of Fiona’s circulation. 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. The removal of large quantities of mass was causing the surface pressure to decrease.

Hurricane Fiona maintained its size as it strengthened during Tuesday night. Winds to hurricane force extended out 45 miles (75 km) from the center of Fiona. Winds to tropical storm force extended out 160 miles (260 km) from the center of circulation. The Hurricane Intensity Index (HII) was 25.1. The Hurricane Size Index (HSI) was 14.8 and the Hurricane Wind Intensity Size Index (HWISI) was 39.9.

Hurricane Fiona will move through an environment favorable for intensification during the next 24 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. Hurricane Fiona is likely to intensify during the next 24 hours. If the inner end of a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause Hurricane Fiona to weaken.

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 north during the next 12 hours. An upper level trough near the East Coast of the U.S. will start to steer Fiona toward the northeast on later Wednesday. On its anticipated track, Hurricane Fiona will affect Bermuda on Thursday night. Fiona could be a major hurricane when it gets to Bermuda. Hurricane Fiona could approach the Canadian Maritimes on Saturday.

Elsewhere over the Atlantic Ocean, Tropical Storm Gaston strengthened west of the Azores. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Gaston was located at latitude 37.5°N and longitude 42.6°W which put it about 850 miles (1370 km) west of the Azores. Gaston was moving toward the northeast at 16 m.p.h. (26 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 1000 mb.