Tropical Storm Emily 2011

Tropical Storm Emily is an active Atlantic tropical cyclone that is currently a threat to the northeastern Caribbean. The fifth named storm of the 2011 Atlantic hurricane season, Emily developed from a strong tropical wave that tracked the open Atlantic for several days in late July. The wave remained fairly disorganized, lacking a defined circulation. By July 31, it approached the Lesser Antilles and became better defined, producing inclement weather over much of the area. Late on August 1, it finally developed a closed circulation center, prompting the National Hurricane Center to declare the formation of Tropical Storm Emily just after it had crossed the islands.

Meteorological history

The cyclogenesis of Tropical Storm Emily was complicated, extending over several days from late July into early August. An easterly tropical wave—an equatorward trough of low pressure moving generally westward—exited the west African coast in the fourth week of July, at which point it became largely embedded within the monsoon trough. Oriented north to south, the wave supported little to no precipitation for a day or two as it traversed the open Atlantic. By July 28, a weak low-pressure center developed along its southern periphery, and over time clusters of moderate, albeit isolated convection increased around the broad wave axis. Atmospheric conditions favored additional development into a tropical cyclone; an anticyclonic circulation soon formed over the system, creating a supportive upper-level environment. It accordingly became better defined over the next couple of days, retaining unusually low surface pressures as well as concentrated showers and thunderstorms. Following a retrace toward the west-northwest, the threat to nearby land became relative to higher chances of development, with several forecast models projecting a path directly into the northeastern Caribbean.

During the morning of July 31, the large low markedly gained in organization, and the National Hurricane Center (NHC) noted it was close to becoming a tropical depression. Later that day, however, the mean low-pressure envelope became increasingly elongated; its westernmost component promptly detached to form a separate tropical wave ahead. This new disturbance featured widely scattered convection, with rainbands briefly impacting the Lesser Antilles. Meanwhile, a reconnaissance aircraft had been investigating the area, although loss of communication limited sufficient data reception. Despite this shortcoming, subsequent surface analysis and buoy observations indicated the disturbance lacked a closed circulation; as such, it did not yet meet the criteria for tropical cyclone classification at the time. As the vigorous low closed in on the Leeward Islands, little change initially occurred in its structure the next day, though associated surface winds rose to near tropical storm-force. A subsequent flight into the system finally revealed a well-defined circulation center near the deep convection mass, passing just to the south of Dominica. Consequently, the NHC marked the formation of Tropical Storm Emily around 2350 UTC August 1, as it accelerated toward the west in response to a mid-level high.

With a relatively dry environment along its projected path, Emily was expected to strengthen only gradually until its passage through the Greater Antilles. For several hours into August 2, the cyclone fluctuated little in intensity and organization, and there were few indications of developing banding features. The NHC further noted that the precise location of the low-level center remained uncertain at the time; therefore, its position within the deepest convection was difficult to determine. Though the storm's appearance improved on satellite images, reconnaissance found it to remain poorly organized, and at the time several forecast models even supported dissipation prior to landfall in Hispaniola. By that afternoon, however, the center began to slow considerably, a sign of possible reorganization proximate to the deep convective mass.

Preparations and impact

In light of high potential for tropical cyclone development, Météo-France declared yellow cyclone alerts for Guadeloupe and Martinique, warning of imminent squally weather. Due to the presence of Emily, officials in Puerto Rico promptly ordered the preparation of over 400 storm shelters, and ensured adequate water supply island-wide. Government workers were dismissed the morning prior to the passage of the storm; national courtrooms opted to remain closed during that time. The United States Coast Guard issued a statement urging residents of Puerto Rico, and the U.S. Virgin Islands to avoid recreational boating and swimming until Emily passes.

An elderly man allegedly died as a result of Emily in Fort-de-France, after he was electrocuted by an exposed wire in his flooded house. Four cruise ships, Oasis of the Seas, Freedom of the Seas, Carnival Dream and Carnival Liberty altered their courses through the Caribbean to avoid impact.JetBlue Airways announced that it would be waiving fees for flights into the Dominican Republic, due to inclement conditions being caused by Emily.

Current storm information

As of 5 p.m. AST (2100 UTC) August 2, Tropical Storm Emily is located within 50 nautical miles of 15.8°N 65.4°W, about 185 mi (300 km) south-southeast of San Juan, Puerto Rico. Maximum sustained winds are 45 knots (50 mph, 85 km/h), with stronger gusts. Minimum central pressure is 1005 mbar (hPa; 29.68 InHg), and the system is moving west-northwest at 10 kt (12 mph, 19 km/h).

Tropical storm force winds extend outward up to 105 miles (165 km) from the center of Emily.

Expected impacts:

Wind: Tropical storm conditions are occurring or imminent in the warning area in the Leeward Islands; tropical storm conditions are expected in Puerto Rico, Culebra, and Vieques later today, and in the Dominican Republic by tonight. Tropical storm conditions are possible in the watch area in the Leeward Islands over the next several hours; in the U.S. Virgin Islands later this morning; and in Haiti by Wednesday.

Rainfall: Emily is expected to produce total rain accumulations of 2 to 4 inches (51 to 100 mm) in the northern Windward Islands and Leeward Islands. Total rain accumulations of 4 to 6 inches are expected in Puerto Rico and the Dominican Republic, with isolated maximum amounts of 10 inches (250 mm) possible. These rains could cause life-threatening flash floods and mud slides in areas of mountainous terrain.

Storm surge: A storm surge will raise water levels by 1 to 2 feet (0.30 to 0.61 m) above normal tide levels in the Tropical Storm Warning area. Near the coast, the surge will be accompanied by large and dangerous waves.

For latest official information see:

The NHC's latest public advisory on Tropical Storm Emily.

The NHC's latest Forecast Discussion on Tropical Storm Emily.