Tropical Depression Nine formed over the northwestern Caribbean Sea on Thursday morning. At 11:00 a.m. EDT on Thursday the center of Tropical Depression Nine was located at latitude 16.9°N and longitude 79.2°W which put it about 210 miles (340 km) southeast of Grand Cayman. The tropical depression was moving toward the northwest at 13 m.p.h. (20 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 1005 mb.
Tropical Storm Warnings were issued for the Cayman Islands. Tropical Storm Warnings were also issued for the Cuban provinces of Matanzas, Mayabeque, Havana, Artemise, Pinar del Rio and the Isle of Youth.
Satellite images indicated the development of a circulation within a tropical wave over the northwestern Caribbean Sea on Thursday morning and the National Hurricane Center designated the system as Tropical Depression Nine. The circulation around Tropical Depression Nine was still organizing. Bands of showers and thunderstorms were starting to form. The strongest thunderstorms were occurring in bands forming on the eastern side of the tropical depression. An upper level low near Florida was producing south-southwesterly winds that were blowing across the western side of Tropical Depression Nine. Those winds were causing moderate vertical wind shear and they were contributing to the asymmetrical distribution of thunderstorms.
Tropical Depression Nine will move around the southwestern part of a subtropical high pressure system during the next several days. The high will steer the depression toward the northwest. On its anticipated track Tropical Depression Nine will move over the Cayman Islands on Thursday night. It could be near western Cuba on Friday evening. The system will move over the Gulf of Mexico during the weekend. It could approach the center coast of the Gulf of Mexico on Sunday.
Tropical Depression Nine will move into an environment that will become more favorable for intensification during the next three days. The upper low near Florida will move off to the northwest and it will weaken. When the upper low weakens, they vertical wind shear will decrease. The tropical depression will move over water where the Sea Surface Temperatures are near 30°C. Tropical Depression Nine could strengthen to a tropical storm later today. It could strengthen to a hurricane during the next 36 hours. An upper level ridge will be over the Gulf of Mexico during the weekend. The upper level winds will be weak and there will be little vertical wind shear. A period of rapid intensification could occur when the system moves toward the central Gulf Coast. It could rapidly intensify to a major hurricane.