Tropical Depression Eleven was a tropical depression during the 1999 Atlantic hurricane season that never became a tropical storm. The depression produced torrential rainfall in Mexico, which caused flash flooding and mudslides.
Total damage is unknown, but the depression killed 400 people by producing the worst flooding in 40 years.
|Formation||October 4, 1999|
|Dissipation||October 6, 1999|
|Highest winds||35 mph|
|Lowest pressure||1002 mbar|
A tropical wave moved off the coast of Africa on September 22. The wave changed little in organization until the wave reached the western Carribean Sea on September 30, at which point a broad area of low pressure developed within the wave. Further development was slow as the system moved across the Yucatan Peninsula and into the Gulf of Mexico. It was not until October 4 that the wave organized enough to be classified as Tropical Depression Eleven, while located 125 nm east-northeast of Veracruz, Mexico. Because steering currents were weak, the depression meandered eratically over the Bay of Campeche throughout its lifetime. There was a notable center reformation between 0600 UTC and 1200 UTC on October 6 based on data from hurricane hunter aircraft. Development of the depression was hindered by a broad surface trough of low pressure, which dominated the central and eastern Gulf of Mexico at that time. On October 6, the depression merged with the trough, while located 130 nm northeast of Veracruz. While ship reports and reconnaissance aircraft data indicate that tropical-storm force winds were present as the cyclone dissipated, these appear to have been associated with a wind surge moving southward over the western Gulf and not with the tropical cyclone.
In spite of the depression's poor organization, it produced widespread and prolonged heavy rainfall over the Mexican states of Puebla, Tabasco, and Veracruz. Press reports indicate that the severe flooding that resulted from the heavy rainfall was responsible for 400 deaths. It is unknown how much of these deaths actually occured from the depression's rainfall, however.