Potential Tropical Cyclone One Discussion Number   4
NWS National Hurricane Center Miami FL       AL012024
1000 AM CDT Tue Jun 18 2024

The disturbance's overall envelope is becoming slightly better 
defined, although there is still no evidence that a well-defined 
center of circulation has developed.  Deep convection is increasing 
somewhat near the estimated center, but the most widespread 
activity is blossoming farther north over the northwestern Gulf of 
Mexico.  The system is still being designated as a potential 
tropical cyclone with 35-kt winds, and an Air Force Reserve 
reconnaissance aircraft is currently surveying the system's wind 
field to assess its structure.  

The disturbance is moving generally northward, or 005/6 kt, 
although the centroid of the cloud pattern suggests it may have 
jogged east a bit.  A continued slow motion is expected through 
tonight as the system gradually consolidates, but a turn toward the 
west with an increase in forward speed is forecast Wednesday and 
Wednesday night due to a mid-level ridge building southwestward 
over the southeastern United States.  The updated NHC track 
forecast is similar to the previous one during the first 24 hours, 
but is then a bit faster after that, trending toward the HCCA and 
TVCA consensus aids.

The system's broad nature will continue to inhibit significant 
strengthening despite otherwise conducive environmental conditions. 
Global model fields suggest the circulation will tighten up and 
develop a well-defined center on Wednesday while the system 
approaches the coast of Mexico.  Intensification becomes more of a 
possibility at that point, and gradual strengthening is forecast on 
Wednesday while the system approaches the coast.

It should be noted that regardless of the exact track of the
low, we expect this system to have a large area of heavy rains,
moderate coastal flooding and tropical-storm-force winds well north
of the center.  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.  The disturbance is very large with rainfall, coastal
flooding, and wind impacts likely to occur far from the center
along the coasts of Texas and northeastern Mexico.

2. Rainfall associated with Potential Tropical Cyclone One 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.  Mudslides are also possible in areas of higher 
terrain across Central America into Northeast Mexico.

3. Moderate coastal flooding is likely along much of the Texas
Coast beginning today and continuing through midweek.

4. Tropical storm conditions are expected to begin tonight or 
Wednesday along portions of the Texas coast south of Port OG��Connor 
and along portions of the coast of northeastern Mexico within the 
Tropical Storm Warning area.


FORECAST POSITIONS AND MAX WINDS

INIT  18/1500Z 21.8N  92.7W   35 KT  40 MPH...POTENTIAL TROP CYCLONE
12H  19/0000Z 22.5N  93.3W   35 KT  40 MPH...POTENTIAL TROP CYCLONE
24H  19/1200Z 23.0N  95.2W   40 KT  45 MPH...TROPICAL CYCLONE
36H  20/0000Z 23.3N  97.5W   45 KT  50 MPH...TROPICAL CYCLONE
48H  20/1200Z 23.3N 100.3W   30 KT  35 MPH...INLAND
60H  21/0000Z...DISSIPATED

$$
Forecaster Berg