Tropical Storm Sam strengthened over the eastern Atlantic Ocean on Thursday morning. At 11:00 a.m. EDT on Thursday the center of Tropical Storm Sam was located at latitude 10.9°N and longitude 38.1°W which put it about 1745 miles (2805 km) east-southeast of the Northern Leeward Islands. Sam moving toward the west at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 1003 mb.

Former Tropical Depression Eighteen strengthened to Tropical Storm Sam on Thursday morning. Tropical Storm Sam was organizing quickly. The inner end of a rainband wrapped around the center of Sam . An eye appeared to be forming at the center of circulation. Bands of showers and thunderstorms were revolving around the center of Tropical Storm Sam. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 45 miles (75 km) from the center of Sam.

Tropical Storm Sam will move through an environment very favorable for intensification during the next 48 hours. Sam will move over water where the Sea Surface Temperatures are near 28˚C. It will move into a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Sam will continue to intensify during the next 36 hours. Sam could strengthen to a hurricane by Friday. Sam could intensify rapidly after an inner core with an eye and an eyewall forms. Sam could intensify to a major hurricane during the weekend.

Tropical Storm Sam will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high will steer Sam toward the west-northwest during the next few days. On its anticipated track Tropical Storm Sam could approach the Northern Leeward Islands next week. Sam could be a major hurricane by that time.