The origin of Tropical Depression Eleven can be traced to a tropical wave
that moved off the west coast of Africa on 22 September. Little development
occurred until the wave reached the western Caribbean on 30 September, when
a broad low pressure area developed. Further development was slow as the
system moved across the Yucatan Peninsula into the Gulf of Mexico, and it
was not until 4 October that the system became a tropical depression
about 125 n mi east-northeast of Veracruz, Mexico.
Steering currents were weak, and Tropical Depression Eleven meandered
erratically over the Bay of Campeche throughout its lifetime
(Figure 1).
There was one notable reformation of the center between 0600 and 1200 UTC 6
October based on data from an Air Force Reserve Hurricane Hunter aircraft.
Development was hindered by a broad surface trough which dominated the
central and eastern Gulf of Mexico, and the depression merged with the
trough about 130 n mi northeast of Veracruz on 6 October. 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.
Although the depression was poorly organized, it contributed to widespread
and prolonged heavy rains over the Mexican states of Puebla, Tabasco, and
Veracruz. Press reports indicate the resulting severe flooding was
responsible for 400 deaths. It cannot be determined at this time how many
of these were directly related to the rains from Tropical Depression
Eleven.
Figure 1. Best track for Tropical Depression Eleven, 4-6 October 1999.
Table 1. Best track, Tropical Depression Eleven, 4-6 October 1999
Date/Time (UTC) |
Position |
Pressure (mb) |
Wind Speed (kt) |
Stage |
Lat. (°N) | Lon. (°W) |
4/0600 | 20.1 | 94.1 | 1005 | 30 | tropical depression |
1200 | 19.5 | 94.0 | 1004 | 30 | " |
1800 | 19.0 | 94.0 | 1003 | 30 | " |
5/0000 | 18.9 | 93.8 | 1002 | 30 | " |
0600 | 19.1 | 94.2 | 1003 | 30 | " |
1200 | 19.4 | 94.5 | 1004 | 30 | " |
1800 | 19.6 | 94.8 | 1005 | 30 | " |
06/0000 | 19.6 | 95.0 | 1006 | 30 | " |
0600 | 19.5 | 95.4 | 1007 | 30 | " |
1200 | 20.4 | 96.4 | 1007 | 30 | " |
1800 | | dissipated |
|
5/0000 | 18.9 | 93.8 | 1002 | 30 | minimum pressure |