Tropical Depression Forms in Gulf of Mexico

(Aug. 10) -- Tropical weather in the Atlantic basin is showing signs of becoming more active, with National Hurricane Center forecasters monitoring three areas for potential development. The most immediate concern is in the Gulf of Mexico, where a tropical depression has formed and it looks increasingly likely that a tropical storm will develop in the next day or two.

The next named storm would be Tropical Storm Danielle.

BP has already halted relief-well drilling in advance of the potential tropical storm, one that will track northwestward toward the northern Gulf of Mexico regardless of its intensification. Tropical storm warnings have been issued from Destin, Fla., to Intracoastal City, La., including New Orleans and Lake Pontchartrain.

As of Tuesday evening, the tropical depression was located 260 miles to the south-southeast of Apalachicola, Fla.; it has produced very heavy rainfall in southern Florida during the past couple of days.

The exceptionally warm water in the Gulf of Mexico is favorable for development into a tropical storm, but overall environmental conditions are not favorable for intense, quick development. The depression will encounter moderate amounts of wind shear -- upper-level wind that is not favorable for tropical storm formation -- but the depression has completed the conversion from a nontropical system into a purely tropical one.

Many tropical storms and hurricanes form in this fashion, but the process tends to be slower. Many of the computer forecast models bring the system ashore along the Louisiana coast on Thursday, which would limit the amount of time that it would have to develop.

If the system were to slow down, the likelihood of strengthening would be greater.


(Image courtesy of NOAA)

The official forecast is for the system to be upgraded to a tropical storm on Wednesday, but regardless of its classification, the system will produce tropical-storm-force conditions over the open waters of the gulf, including dangerous thunderstorms, strong wind gusts and very rough seas. The tropical storm conditions will spread into coastal areas on Wednesday night or Thursday.

Hurricane forecasters are more accurate when projecting the path of a hurricane than the intensity, which means that residents along the coast of the northern Gulf of Mexico need to monitor the system closely.

The other area that could become a tropical storm is located in the central Atlantic. Forecasters have been monitoring this system for the past couple of days. It poses no immediate threat to land and is located in an area where it's extremely unlikely to ever threaten the United States.

The third area of concern is a tropical wave located about 700 miles to the east of the Leeward Islands. Any intensification with this system will be slow -- forecasters give it just a 10 percent chance of developing in the next two days -- but it's in an area where developing storms often pose a threat to the Caribbean or the United States.