Tuesday, August 25, 2015

Tropical Storm Erika (2015)

Storm Active: August 24-29

Around August 20, a tropical wave moved off of the African coastline. It passed just south of the Cape Verde islands shortly afterward, and moved swiftly into the central Atlantic. A low pressure center soon developed along the wave, and it begin to organize in earnest by August 23. The next day, the system acquired enough definition to be considered a tropical cyclone. Since an Atlantic buoy measured gale force winds near the center, it was classified Tropical Storm Erika.

Erika initially struggled with moderate wind shear and dry air aloft. On August 25, the center became exposed as convection retreated into the southeast quadrant. However, thunderstorm activity made a comeback overnight as the system approached the Leeward Islands from the east. Conditions deteriorated in the islands that night, for while Erika still possessed no visible banding features and was poorly organized, it packed a large area of heavy rainfall and thunderstorm activity. The center reformed to the south during the morning of August 27 as Erika entered the Caribbean.

Continuing to struggle with strong shear, the system remained badly organized that day, and though it passed fairly close to Puerto Rico from the south, most of the strongest winds remained in the southeastern quadrant over open water. By the morning of August 28, Erika had turned west-northwestward toward the island of Hispaniola. Later that day, the cyclone moved ashore on the south coast near the border of the Dominican Republic and Haiti, bringing scattered areas of heavy rain and tropical storm force winds. Land interaction weakened and disorganized the system further, making the center tremendously difficult to locate overnight. Though the circulation emerged over water, the system could not recover and Erika dissipated during the morning of August 29 near Cuba. The remnants of Erika continued toward the northwest, bringing rain to Cuba and eventually Florida. Moisture associated with Erika also contributed to thunderstorm activity over the Carolinas during the final days of August.

Erika failed to achieve significant organization due to constant vertical wind shear. The above image shows Erika over the Lesser Antilles.

Erika dissipated on August 29; the last several points of its track indicate the positions of its remnants over the following day.

No comments: