A center of circulation quickly organized within a tropical wave on Monday night and the National Hurricane Center designated the system as Tropical Storm Gaston.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Gaston was located at latitude 12.6°N and longitude 30.7°W which put it about 450 miles (725 km) west-southwest of the Cape Verde Islands.  Gaston was moving toward the west-northwest at 18 m.p.h. (30 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 1005 mb.

The circulation consolidated rapidly around the center of Tropical Storm Gaston on Monday.  Several spiral bands of thunderstorms formed close to the center and additional bands formed farther from the center.  The thunderstorms near the center began to generate upper level divergence, which pumped mass away from the center.

Tropical Storm Gaston is moving through an environment that is favorable for intensification.  It is over water where the Sea Surface Temperature is near 28°C.  The upper level winds are light and there is little vertical wind shear.  Gaston is likely continue to intensify steadily during the next several days and it is expected to become a hurricane.  Once a tightly organized core consolidates completely, Gaston could undergo a period of more rapid intensification.

A subtropical ridge is steering Tropical Storm Gaston toward the west-northwest and that general motion is expected to continue for a day or so.  The ridge is expected to weaken northwest of Gaston, and the tropical storm is expected to turn more toward the north during the middle of the week.  Gaston could be moving out into the Central Atlantic Ocean by the end of the week.