Tropical Storm Hermine
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Christopher HenryTropical Storm Hermine
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Christopher HenryTropical Storm Hermine was the eighth tropical cyclone and named storm of the 1998 Atlantic hurricane
season. Hermine developed from a tropical wave that emerged from the west coast of Africa on September 5. The wave moved westward across the Atlantic Ocean, and on entering the northwest Caribbean interacted with other weather systems. The resultant system was declared a tropical depression on September 17 in the central Gulf of Mexico. The storm meandered north slowly, and after being upgraded to a tropical storm made landfall onLouisiana, where it quickly deteriorated into a tropical depression again on September 20. Before the storm's arrival, residents of Grand Isle, Louisiana were evacuated. As a weak tropical storm, damages from Hermine were light. Rainfall spread from Louisiana through Georgia, causing isolated flash flooding. In some areas, the storm tide prolonged the coastal flooding from a tropical cyclone. Gusty winds were reported. Associated tornadoes in Mississippi damaged mobile homes and vehicles, and inflicted one injury. While Hermine was not of itself a particularly damaging storm, its effects combined with those of other tropical cyclones, and resulted in agricultural damage.
On September 5, 1998, a tropical wave emerged from the west coast of Africa and entered the Atlantic Ocean. The wave was not associated with any thunderstorm activity until it reached the Windward Islands, when cloud and shower activity began to increase. Continuing westward, the disturbance approached the South American coastline and turned into the northwest Caribbean. The wave interacted with an upper-level low-pressure system and another tropical wave that entered the region. At the time, a large monsoon-type flow prevailed over Central America, part of the Caribbean Sea, and [1] the Gulf of Mexico. Anarea of low pressure developed over the northwestern Caribbean, and at about 1200 UTC on September 17, the system was sufficiently organized to be declared a tropical depression [1][2] in the central Gulf of Mexico. Initially, the cloud pattern associated with the system featured a tight and well-defined circulation, as well as clusters of deep convection south of the center. Due to the proximity of a large upper-level lowpressure area in the southern Gulf of Mexico, the surrounding environment did not favor [3] [4] intensification. Influenced by the low, the depression moved southward. The system completed a [1] [5] cyclonic loop in the central gulf, and by early on September 18 was drifting northward. As a result [6] of wind shear, the center of circulation was separated from the deep convective activity. Early the next day, deep convection persisted in a small area northeast of the center. Forward motion was nearly [7] stationary, with a gradual drift east-southeastward. Despite the wind shear, the depression attained [1] tropical storm status at 1200 UTC; as such, it was named Hermine by the National Hurricane Center. Shortly after being upgraded to a tropical storm, Hermine reached its peak intensity with maximum [1] sustained winds of 45 mph (75 km/h). The tropical storm-force winds were confined to the eastern [8] semicircle of the cyclone. Hermine tracked northward and approached the coast, where it nearly [9] stalled. A continually weakening storm, it moved ashore near Cocodrie, Louisiana at 0500 UTC on September 20 with winds of 40 miles per hour (64 km/h), and then deteriorated into a tropical [1] depression. On its landfall, associated rain bands were deemed "not very impressive", although there was a rapid increase in thunderstorm activity east of the center. The thunderstorms produced heavy rainfall in parts of southeastern Louisiana and southern Mississippi. The storm progressively weakened [10] as the circulation moved northeastward, and dissipated at 1800 UTC. Initially, it was believed that Hermine's remnants contributed to the development of Hurricane Karl; however, this belief was not [11] confirmed.