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Remnants Of Fred Discussion Number 20
NWS National Hurricane Center Miami FL AL062021
1100 AM EDT Sat Aug 14 2021
A combination of shear caused by an upper-level trough over the
Gulf of Mexico and land interaction has caused Fred to degenerate
into an open wave. Surface observations from Cuba do not show a
closed circulation, and satellite imagery shows at least two
vorticity centers embedded in a large trough. The strongest
convection is currently near and southeast of a vorticity center
near the Isle of Youth. The initial position is a mean position
between the vorticity center, and the initial intensity of 30 kt is
based on Air Force Reserve Hurricane Hunter aircraft data to the
northeast of the estimated center position.
The global models forecast the upper-level trough to move northward
and weaken during the next 24 h and indicate that Fred will re-form
a closed circulation over the eastern Gulf of Mexico Sunday morning.
Given the strength of the upper-level trough, that forecast may
well be too bullish. However, given the agreement in the guidance,
the revised intensity forecast will call for Fred to regain
tropical cyclone status at about the 24 h point, followed by gradual
strengthening in a less than ideal upper-level wind environment
until landfall along the northern Gulf coast. After landfall, the
system should weaken and dissipate between 96-120 h.
The initial motion is a very uncertain 300/10. The system is
expected to move west-northwestward to northwestward around the
western periphery of the subtropical ridge, with a turn toward the
north as the system nears the northern Gulf coast in 60-72 h.
While the forecast guidance is in good agreement on this general
scenario, there is uncertainty as to where the center of Fred will
be when it re-forms. Therefore, users should not concentrate on
the details of the forecast track, which could change quite a bit
during the next 24-36 h.
Although all coastal watches and warnings are discontinued at this
time, the National Hurricane Center will continue 6-hourly
advisories on the remnants of Fred in anticipation of
re-development and the potential need for watches and warnings on
the northern Gulf coast later in the weekend.
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
2. Fred is forecast to regenerate as a tropical cyclone over
the Gulf of Mexico on Sunday, and bring a risk of tropical storm
conditions to portions of the northern Gulf coast, especially from
coastal Mississippi to the Florida Panhandle beginning on Monday.
Watches may be required for a portion of this area later in the
FORECAST POSITIONS AND MAX WINDS
INIT 14/1500Z 23.3N 83.2W 30 KT 35 MPH...DISTURBANCE
12H 15/0000Z 24.1N 84.2W 30 KT 35 MPH...DISTURBANCE
24H 15/1200Z 25.7N 85.5W 30 KT 35 MPH...TROPICAL CYCLONE
36H 16/0000Z 27.4N 86.7W 35 KT 40 MPH
48H 16/1200Z 28.7N 87.4W 45 KT 50 MPH
60H 17/0000Z 30.0N 87.7W 45 KT 50 MPH
72H 17/1200Z 31.5N 87.5W 35 KT 40 MPH...INLAND
96H 18/1200Z 35.0N 86.5W 20 KT 25 MPH...POST-TROP/INLAND