Tropical Storm Sean formed over the eastern Atlantic Ocean on Wednesday morning. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Sean was located at latitude 10.3°N and longitude 33.1°W which put it about 725 miles (1170 km) west-southwest of the Cabo Verde Islands. Sean was moving toward the west-northwest at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1006 mb.

A low pressure system over the Atlantic Ocean west-southwest of Cabo Verde Islands strengthened on Wednesday morning and the U.S. National Hurricane Center designated the system as Tropical Storm Sean. More thunderstorms began to form near the center of Sean’s circulation. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away to the north of the tropical storm. Winds to tropical storm force extended out 90 miles (145 km) in the northeastern quadrant of Tropical Storm Sea. The winds in the other parts of Sean’s circulation were blowing at less than tropical storm force.

Tropical Storm Sean will move through an environment somewhat favorable for intensification during the next 24 hours. Sean will move over water where the Sea Surface Temperatures are near 29°C. It will move under the eastern side of an upper level trough over the central Atlantic Ocean. The upper level trough will produce southerly winds that will blow toward the top of Sean’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification, but the shear may not be strong enough to prevent intensification. Tropical Storm Sean is likely to intensify during the next 24 hours.

Tropical Storm Sean will move around the southwestern part of a high pressure system that extends from West Africa to the eastern Atlantic Ocean. The high pressure system will steer Sean toward the west-northwest during the next 24 hours. On its anticipated track, Tropical Storm Sean will move farther away from the Cabo Verde Islands.