Hurricane Dorian strengthened north of Puerto Rico on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Dorian was located at latitude 19.7°N and longitude 66.0°W which put it about 90 miles (145 km) north of San Juan, Puerto Rico.  Dorian was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 110 m.p.h. (170 km/h).  The minimum surface pressure was 986 mb.

The circulation around Hurricane Dorian strengthened steadily on Wednesday.  A circular eye with a diameter of 14 miles (22 km) formed at the center of circulation.  A closed ring of thunderstorms surrounded the eye and the strongest winds were occurring in the northeastern part of that ring.  Bands of showers and thunderstorms were revolving around the core of Hurricane Dorian.  Storms near the core were generating upper level divergence which was pumping mass away to the north and northeast of the hurricane.  The circulation around Hurricane Dorian remained fairly small.  Winds to hurricane force extended out about 20 miles (30 km) in the northeastern quadrant of Dorian.  Winds to tropical storm force extended out about 70 miles from the center of circulation.

Hurricane Dorian will move through an environment favorable for intensification during the next several days.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  It will move into an area where the upper level winds are relatively weak and there will be little vertical wind shear.  Hurricane Dorian is very likely to intensify during the next 48 hours and it could intensify rapidly at times.  Dorian is likely to strengthen into a major hurricane.

An upper level low near the Bahamas will pull Hurricane Dorian toward the northwest during the next 24 to 36 hours.  A strong ridge of high pressure will build north of Dorian on Friday.  The high will block Dorian from moving north and it will turn it toward the west-northwest.  On its anticipated track Hurricane Dorian could be near the northern Bahamas on Saturday night.  Dorian could approach the east coast of Florida by later on Sunday.  Dorian is likely to be a major hurricane when it approaches Florida.