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Hurricane Dennis

Category 4 Atlantic hurricane in 2005

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Through Cuba, Atmospheric pressure and Landslide

In the Caribbean, the outer bands of Hurricane Dennis brought tropical storm-force winds and heavy rain to parts of Haiti, resulting in floods and landslides. A total of 3,058 homes were damaged and 929 were destroyed. Hundreds of livestock were killed, causing significant harm to Haiti's agricultural industry. The storm resulted in 56 fatalities and caused approximately $50 million in damages. In Jamaica, Dennis produced 24.54 in (623 mm) of rainfall in Mavis Bank. The resultant floods severely affected Jamaica's agriculture industry, killing nearly 160,000 livestock and leaving around 100,000 customers without electricity. The storm killed one person in Jamaica and resulted in over $34.5 million in damages. In Cuba, rainfall peaked at 43 in (1,092 mm). Approximately 120,000 houses were damaged and 15,000 homes were destroyed. Nationwide, 2.5 million people lost access to water while 70% of the water sources in Granma Province were contaminated. Its agricultural industry was also affected, with almost 27,000 hectares (67,000 acres) of agricultural land being destroyed in the provinces of Cienfuegos and Granma. The impact led to 16 fatalities and caused an estimated $1.4 billion in damage to the country.

The impact of Hurricane Dennis on the United States was also significant, resulting in $2.5 billion in damages and 17 fatalities. More than 1 million people lost power, and a power worker was killed while restoring electricity in Alabama. In Florida, the hurricane brought hurricane-force winds as strong as 121 mph (195 km/h) to the Florida Panhandle, while rainfall reached 8.70 in (221 mm) in Bristol. Additionally, Dennis produced a 6 to 9 ft (2 to 3 m) storm surge, which caused significant flooding along Apalachee Bay, well east of the landfall. The estimated damages in Florida amounted to $1.5 billion, and the hurricane killed 14 people. In neighboring Alabama, Dennis brought hurricane-force winds, a 3–6.5 ft (1–2 m) storm surge, and heavy rainfall peaking at 12.80 in (325 mm) in Camden. Due to the extensive damage, the name Dennis was retired by the World Meteorological Organization.

Meteorological history

The tropical wave that became Dennis was identified by the National Hurricane Center (NHC) on June 26, 2005, well inland over Africa. It moved to the west and later emerged into the Atlantic Ocean on June 29. Dry conditions over the Sahara initially inhibited development, though the wave found more favorable conditions and intensified into a tropical depression on July 4 while nearing the Windward Islands. The depression soon crossed the island country of Grenada before entering the Caribbean, where increasingly favorable environmental factors, such as low wind shear and high sea surface temperatures, fueled intensification. Turning west-northwest, the system achieved tropical storm status on July 5 and hurricane status the following day. The formation of a well-defined eye and central dense overcast signaled Dennis's intensification into a Category 3 hurricane on July 7, as it traversed the Jamaica Channel.

The powerful storm struck the western tip of Granma Province, Cuba, as a Category 4 hurricane early on July 8. Overland, Dennis weakened to Category 3 intensity, but it quickly moved back over water and regained its strength. Moving parallel to the southwestern coast of Cuba, Dennis reached its peak winds of 150 miles per hour (240 km/h). It soon weakened to winds of 140 mph (230 km/h) later that day because of an eyewall replacement cycle before making a second landfall in the country, this time in Matanzas Province. Interaction with the mountains of Cuba caused significant weakening; once Dennis emerged over the Gulf of Mexico on July 9, it quickly reorganized in favorable conditions. The hurricane reached Category 4 strength for the third time on July 10 as it approached Florida, attaining its lowest barometric pressure of 930 mbar (hPa; 27.46 inHg). This ranked Dennis as the strongest hurricane in the Atlantic basin to form before August; however, this record was broken just six days later by Hurricane Emily, which surpassed Dennis and attained Category 5 status. Weakening ensued as the hurricane approached the Florida Panhandle, the storm ultimately making landfall over Santa Rosa Island on July 10 as a Category 3. Weakening continued as the cyclone moved further inland, and the storm quickly lost tropical cyclone status. Dennis' remnant circulation remained, traversing the river valleys of the Mississippi and Ohio before finally dissipating over Ontario on July 18.

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