Tropical Storm Alberto Discussion Number   9
NWS National Hurricane Center Miami FL       AL012024
400 PM CDT Wed Jun 19 2024

There hasn't been much additional data to help assess the structure
of Alberto since the Air Force Reserve reconnaissance aircraft 
departed the system a few hours ago.  However, recent satellite 
images and data from NOAA buoy 42055 suggest that the center may 
have re-formed a bit to the southwest since this morning.  Another 
reconnaissance aircraft is scheduled to investigate the system 
later this evening.  For now, the maximum winds remain 35 kt.

Because of the re-formation of the center, the recent motion has
been west-southwestward, or 250/8 kt.  However, Alberto is expected
to resume a westward motion and speed up over the next 24 hours as
a mid-level ridge over the eastern U.S. builds westward.  The track
guidance is in good agreement that Alberto's center will reach the
coast of Mexico early Thursday, and the NHC track forecast is close
to a blend of the TVCA and HCCA models.  Some slight strengthening 
is still possible through tonight while Alberto remains over water, 
and the NHC intensity forecast continues to show a peak intensity of 
about 40 kt.  The circulation could dissipate over the mountains of 
Mexico as soon as 24 hours from now, but for continuity a 24-hour 
forecast is provided with dissipation shown at 36 hours.

More importantly, because of Alberto's large size, it will continue 
to produce heavy rains, moderate coastal flooding, and 
tropical-storm-force winds across portions of southern Texas and 
northeastern Mexico regardless of its exact track.  It is worth 
noting that the official wind speed probabilities are likely 
underestimating the chances of tropical-storm-force winds along the 
Texas coast because of the unusually large and asymmetric area of 
strong winds on the northern side of the circulation.


Key Messages:

1. Users are reminded not to focus on the exact forecast track of
this system.  Alberto is very large with rainfall, coastal flooding,
and wind impacts occuring far from the center along the coasts of 
Texas and northeastern Mexico.

2. Heavy rainfall associated with Tropical Storm Alberto will impact 
large regions of Central America, north across northeastern Mexico 
and into South Texas. This rainfall will likely produce considerable 
flash and urban flooding along with new and renewed river flooding. 
Life-threatening flooding and mudslides are likely in and near areas 
of higher terrain across the Mexican states of Coahuila, Nuevo Leon, 
and Tamaulipas, including the cities of Monterrey and Ciudad 
Victoria.

3. Moderate coastal flooding is likely along much of the Texas
Coast through Thursday.

4. Tropical storm conditions are expected today along portions of
the Texas coast south of San Luis Pass and along portions of the
coast of northeastern Mexico within the Tropical Storm Warning area.


FORECAST POSITIONS AND MAX WINDS

INIT  19/2100Z 21.9N  95.3W   35 KT  40 MPH
12H  20/0600Z 22.0N  97.0W   40 KT  45 MPH
24H  20/1800Z 22.1N 100.9W   30 KT  35 MPH...INLAND
36H  21/0600Z...DISSIPATED

$$
Forecaster Berg