Hurricane Gustav - Meteorological History

Meteorological History

Gustav formed out of a tropical wave that had previously produced t-rain and squalls in the Lesser Antilles. It developed well-defined curved bands and briefly exhibited an upper-level eye feature. The NHC designated it Tropical Depression Seven and dispatched a hurricane hunter aircraft to investigate the system. At the time, the system had a well-defined outflow in all but the southeast and southwest quadrant, and data from the hurricane-hunter aircraft confirmed that the tropical depression had strengthened into a tropical storm, which was soon designated Tropical Storm Gustav. A brief period of disorganization proved to be temporary as a well-defined eye wall formed that same night. In the early hours of August 26, as the storm approached Haiti's southwestern peninsula, another hurricane hunter aircraft confirmed what forecasters already suspected—that Gustav had strengthened into a hurricane with winds topping 90 mph (150 km/h). Before reaching Haiti, its satellite presentation continued to intensify, a central dense overcast became more prominent, and the minimum central pressure fell.

Hurricane Gustav regained a pronounced eye as it made landfall on Haiti, with 75 mph (121 km/h) winds, near the town of Jacmel. As the hurricane moved over Haiti's mountainous terrain its circulation was disrupted and it lost a little strength. Although downgraded to a tropical storm, it still had a pronounced eye in its mid- and upper-level structures. Its outflow improved throughout the night of August 26, and the system was not very disrupted when it moved back over water into the Gulf of Gonâve. However, the storm's movement slowed, and continued interaction with nearby Haiti, combined with the incursion of mid-level dry air from the northeast, resulted in further weakening during the day on August 27. The storm began a west-southwesterly movement that brought it closer to Jamaica. On the morning of August 28 it was found that, overnight, Gustav had either reformed farther to the south or had moved farther to the south than previously thought. The storm was also found to have restrengthened nearly to hurricane status. It then was upgraded to a hurricane again during the late afternoon of August 29. At 11:00 a.m EDT (1500 UTC) on August 30, as Gustav neared the west end of Cuba, it was upgraded to a Category 3 hurricane on the Saffir-Simpson Hurricane Scale, with sustained winds near 125 mph (205 km/h). Gustav continued its rapid deepening trend, and three hours later, it had already reached Category 4 strength. Gustav's maximum sustained winds had reached 155 mph (250 km/h) with a minimum pressure of 941 millibars.

On August 30 Gustav made landfall twice on Cuba: first, on Isla de la Juventud and then on the mainland near the community of Los Palacios in Pinar del Río Province. By the early hours of August 31, Gustav entered the Gulf of Mexico with maximum sustained winds of 135 mph (217 km/h) and minimum central pressure of 958 millibars. During August 31, the storm moved in a northwest direction slightly losing its strength (despite passing over a shortened Loop Current) with sustained winds at 115 mph. On the evening of August 31, Gustav weakened to a Category 2 hurricane and remained at such intensity until landfall. Gustav made landfall along the Louisiana coast with 105 mph (170 km/h) winds near Cocodrie, at about 9:30 a.m CDT (1430 UTC). By 10 pm CDT, Gustav had been downgraded to a Tropical Storm with winds of 60 mph (95 km/h) about 20 miles (30 km) southwest of Alexandria, Louisiana and by 4 am CDT on September 2 Gustav had diminished to a Tropical Depression with a threat of severe flooding in the lower Mississippi Valley and eastern Texas.