ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
 
Tropical Depression Fred Discussion Number  19
NWS National Hurricane Center Miami FL       AL062021
500 AM EDT Sat Aug 14 2021
 
The interaction with the landmass of Cuba has significantly 
disrupted the circulation of Fred.  In fact, radar data from Cuba, 
satellite images, earlier ASCAT data, and surface observations 
suggest that the system is likely an open trough with the strongest 
winds and deep convection occurring to the south of central Cuba.  
Fred is being maintained as a tropical depression for now, but data 
from the Air Force Hurricane Hunters later this morning will likely 
confirm if it is a depression or not.  The initial intensity is 
held at 30 kt based on the aforementioned ASCAT data.  Bands of 
heavy rain are now spreading across the Florida Keys.
 
The initial motion of 295/11 kt is highly uncertain since its not 
clear if Fred has a center.  Even though the storm has moved farther 
west than previously expected, the overall track forecast reasoning 
has not changed much.  Fred is expected to turn northwestward by 
tonight and northward by Sunday night as the cyclone rounds the 
western periphery of a subtropical ridge.  The new track forecast 
has been nudged to the west again to be in better agreement with the 
latest model consensus aids.  Based on the new track forecast, Fred 
is expected to pass west of the lower Florida Keys later today and 
make landfall along the western Florida Panhandle or Alabama coast 
Monday night or early Tuesday.
 
Although Fred is very disorganized at the moment, the global models 
show the circulation becoming better defined tonight or on Sunday as 
the cyclone moves over the eastern Gulf of Mexico in slightly lower 
wind shear conditions.  The storm is expected to strengthen some 
during the next couple of days, but significant intensification 
seems unlikely as southerly shear is anticipated to increase before 
the system reaches the Gulf coast on Monday.  GFS and ECMWF 
simulated satellite images show an asymmetric cyclone with most of 
the associated convection and stronger winds on its east side while 
Fred moves across the Gulf of Mexico. After landfall, steady 
weakening is expected, and Fred is likely to dissipate by the middle 
of next week.  The NHC intensity forecast is largely an update of 
the previous one and lies near the high end of the model guidance.
 
 
KEY MESSAGES:
 
1. Today through Monday, heavy rainfall could lead to areal, urban, 
and small stream flooding impacts, and cause new and renewed river 
flooding, across southern Florida, the Big Bend, and Panhandle.  
From Monday onward, heavy rain and flood impacts could extend into 
other portions of the Southeast and into the southern and central 
Appalachians and Piedmont as Fred interacts with a front in the 
area. 
 
2. Tropical storm conditions are expected in portions of the Lower
Florida Keys later today, where a Tropical Storm Warning is in
effect.
 
3. There is a risk of tropical storm conditions in the Florida 
Panhandle and coastal Alabama beginning on Monday.  Watches may be 
required for a portion of this area later today.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  14/0900Z 23.3N  81.7W   30 KT  35 MPH
 12H  14/1800Z 24.0N  83.1W   30 KT  35 MPH
 24H  15/0600Z 25.4N  84.6W   35 KT  40 MPH
 36H  15/1800Z 27.0N  85.8W   40 KT  45 MPH
 48H  16/0600Z 28.4N  86.7W   45 KT  50 MPH
 60H  16/1800Z 29.8N  87.3W   50 KT  60 MPH
 72H  17/0600Z 30.9N  87.4W   40 KT  45 MPH...INLAND
 96H  18/0600Z 34.4N  86.6W   25 KT  30 MPH...INLAND
120H  19/0600Z...DISSIPATED
 
$$
Forecaster Cangialosi
 
NNNN