Florence Strengthens Back Into a Hurricane

Florence strengthened back into a hurricane on Sunday morning.  At 11:00 a.m. EDT on Sunday the center of Hurricane Florence was located at latitude 24.4°N and longitude 56.3°W which put it about 750 miles (1210 km) southeast of Bermuda.  Florence was moving toward the west at 6 m.p.h. (10 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 984 mb.

Hurricane Florence was better organized on Sunday morning.  A NOAA research aircraft reported a circular eye with a diameter of 24 miles (39 km).  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Florence.  Storms near the core were generating upper level divergence which was pumping mass away from the hurricane.  Winds to hurricane force extended out about 20 miles (35 km) to the east of the center of circulation.  Winds to tropical storm force extended out about 115 miles (185 km) to the north of the center and about 50 miles (80 km) to the south of the center.

Hurricane Florence will be moving through an environment favorable for intensification.  Florence 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.  Hurricane Florence will strengthen and it could intensify rapidly at times.  Florence is likely to be a major hurricane on Monday.

Hurricane Florence will move around the western end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Florence in a general west-northwesterly direction.  On its anticipated track the center of Hurricane Florence will approach the southeast coast of the U.S. on Thursday.  It is likely to be a major hurricane at that time.

Elsewhere, Tropical Storm Helene and Tropical Storm Isaac moved westward over the tropical Atlantic Ocean.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Helene was located at latitude 13.2°N and longitude 25.0°W which put it about 120 miles (195 km) south-southwest of the Cabo Verde Islands.  Helene was moving toward the west at 13 m.p.h. (20 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 997 mb.  Tropical Storm Warnings were in effect for Santiago, Fogo and Brava.

At 11:00 a.m. EDT on Sunday the center of Tropical Storm Isaac was located at latitude 14.3°N and longitude 39.1°W which put it about 1470 miles (2370 km) east of the Windward Islands.  Isaac was moving toward the west at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 65 m.p.h. (105km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 999 mb.