Eta Strengthens Back to Tropical Storm, Warnings Issued for Florida

Former Tropical Depression Eta strengthened back to a tropical storm on Saturday morning and Tropical Storm Warnings for parts of South Florida and the Florida Keys. At 1:00 p.m. EST on Saturday the center of Tropical Storm Eta was located at latitude 20.0°N and longitude 80.1°W which put it about 50 miles (80 km) north of Grand Cayman Island. Eta was moving toward the northeast at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 995 mb.

A Tropical Storm Warning was issued for the portion of the coast from Golden Beack to Chokoloskee, Florida. A Tropical Storm Warning was issued for the Florida Keys from Ocean Reef to the Dry Tortugas. Tropical Storm Warnings were in effect for the Cayman Islands and the Cuban provinces of Camaguey, Ciego de Avila, Sancti Spiritus, Villa Clara, Cienfuegos and Matanzas. A Tropical Storm Warning was in effect for the Northwestern Bahamas including the Abacos, Andros Island, the Berry Islands, Bimini, Eleuthera, Grand Bahama Island and New Providence. Tropical Storm Watches were issued for the portion of the coast from Chokoloskee to Englewood, Florida and from JGolden Beach to the Brevard/Volusia County Line. A Tropical Storm Watch was in effect for Lake Okeechobee. A Tropical Storm Watch was in effect for the Cuban provinces of La Habana, Artemisa y Mayabeque, Pinar del Rio and the Isle of Youth.

Observations from a U.S. Air Force Reserve Hurricane Hunter plane and from Grand Cayman Island indicated that the center of former Tropical Depression Eta reformed in a cluster of thunderstorms near Grand Cayman. The reconnaissance plane was still sampling the circulation around Tropical Storm Eta but the available date suggested that it was much better organized. The inner end of a rainband was wrapping around the eastern and northern part of the center of circulation. Other bands of showers and thunderstorms were revolving around the core of Eta. Storms near the core were generating upper level divergence which was pumping mass away to the northeast of the tropical storm. The removal of mass was allowing the surface pressure to decrease and Tropical Storm Eta was intensifying more quickly. Winds to tropical storm force extended out 60 miles (95 km) from the center of Eta.

Tropical Storm Eta will move through an environment favorable for intensification during the next 12 to 18 hours. Eta will move over water where the Sea Surface Temperature is near 29°C. It will initially be under an upper level ridge where the winds are weaker. There will be less vertical wind shear under the ridge. Eta could intensify rapidly during the next 12 hours and it could strengthen to a hurricane. Eta is likely to weaken when it crosses Cuba on Saturday night . The Sea Surface Temperature of the water north of Cuba is near 29°C. So, Eta is likely to strengthen after it crosses Cuba. Eta could strengthen to a hurricane when it approaches South Florida. An upper level low over the western Gulf of Mexico will produce southwesterly winds which will blow toward the top of Eta on Sunday. Those winds will cause more vertical wind shear, which could limit further intensification of Eta. The wind shear caused by the upper low could eventually cause Eta to develop a structure more like a subtropical cyclone.

An upper low over the western Gulf of Mexico will be the primary feature steering Eta. Counterclockwise rotation around the cutoff low will pull Eta more toward the northeast on Saturday. On its anticipated track Eta could move across Cuba on Saturday night and it could drop heavy rain when it does so. The upper low will steer Eta toward the northwest on Sunday. Eta will approach South Florida and the Florida Keys on Sunday night. It could be a hurricane at that time. Eta will bring gusty winds and locally heavy rain to the Florida Keys and South Florida. A high pressure system over the Atlantic Ocean will interact with the circulation around the northern side of Eta to produce strong easterly winds which will blow toward the coast of Southeast Florida. Those winds will push water toward the coast and the water level could rise up to six feet (2 meters).