An Air Force Reserve Hurricane Hunter aircraft investigated Potential Tropical Cyclone 02 on Monday afternoon as it moved closer to Trinidad and the plane found a closed circulation. Based on data from the reconnaissance plane the National Hurricane Center classified the system as Tropical Storm Bret. At 8:00 p.m. EDT on Monday the center of Tropical Storm Bret was located at latitude 9.5°N and longitude 60.5°W which put it about 85 miles (135 km) southeast of Trinidad. Bret was moving toward the west-northwest at 25 m.p.h. (40 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 1008 mb.
Tropical Storm Warnings are in effect for Grenada, Trinidad, Tobago and the coast of Venezuela from Pedernales to Cumana. Tropical Storm Watches have been issued for Aruba, Bonaire, and Curacao.
The reconnaissance plane found a well organized center of circulation at the surface. The strongest winds were occurring in vigorous bands of thunderstorms located north of the center of circulation. Weaker showers and thunderstorms were occurring in bands south of the center of circulation. The thunderstorms north of the center were generating upper level divergence which was pumping mass away to the north of the tropical storm. The circulation of Tropical Storm Bret is fairly small. Winds to tropical storm force only extend out about 80 miles (130 km) to the north of the center of circulation.
Tropical Storm Bret will move through an environment that will only be marginally favorable for intensification on Tuesday. Bret will move over water where the Sea Surface Temperature is near 29°C. An upper level ridge east of Bret and an upper level trough to the west are producing southerly winds which are generating moderate vertical wind shear. The vertical wind shear may be responsible for the asymmetrical distribution of thunderstorms. The shear will also inhibit intensification during the next 24 hours, although some intensification may possible. When Bret moves into the Caribbean Sea, the vertical wind shear will increase. Tropical Storm Bret will also move very close to the north coast of Venezuela. It could pull drier air from South America into the southern part of the circulation, which would contribute to further weakening.
The subtropical high pressure system over the Atlantic Ocean is steering Tropical Storm Bret rapidly toward the west-northwest. A fast west-northwesterly motion is forecast to continue for several more days. On its anticipated track Tropical Storm Bret will move across Trinidad, near the north coast of Venezuela and toward Aruba, Bonaire, and Curacao. It will bring gusty winds and locally heavy rain to all of those places.