Tropical Depression 13 Forms, Watch Issued for Saba and St. Eustatius

Tropical Depression Thirteen formed about 1000 miles (1600 km) east of the Lesser Antilles on Wednesday night.  At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Thirteen was located at latitude 14.6°N and longitude 47.9°W which put it about 1035 miles (1670 km) east-southeast of the northern Leeward Islands.  The depression was moving toward the west-northwest at 20 m.p.h. (32 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1008 mb.

A Tropical Storm Watch was issued for Saba and St. Eustatius.

A distinct center of circulation developed within a tropical wave east of the Lesser Antilles on Wednesday night and the National Hurricane Center designated the system as Tropical Depression Thirteen.  The circulation around the depression was still organizing.  Thunderstorms were building near the newly formed center of circulation.  Bands of showers and thunderstorms were developing.  The stronger thunderstorms were in bands in the northern half of the circulation.  Storms near the center began to generate upper level divergence which was pumping mass away from the depression.

Tropical Depression Thirteen will move through an environment favorable for intensification during the next few days.  The depression will move over water where the Sea Surface Temperature is near 28°C.  It will move a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Depression Thirteen will likely strengthen gradually at first while the circulation is organizing.  If an inner core develops, then the rate of intensification could increase.

Tropical Depression Thirteen will move south of the subtropical high pressure system over the North Atlantic Ocean.  The high will steer the depression toward the west-northwest during the next few days.  On its anticipated track Tropical Depression Thirteen could approach the northern Leeward Islands on Friday.