Tropical Storm Fred Discussion Number 28
NWS National Hurricane Center Miami FL AL062021
1000 AM CDT Mon Aug 16 2021
Fred became better organized on satellite and radar images this
morning, with the center fairly well embedded within a small CDO
and a large convective band over the eastern portion of the
circulation. The Air Force Hurricane Hunters found flight-level
winds that supported an intensity of 50 kt, and data from
the aircraft also found that the central pressure had fallen to 993
mb, although the most recent pressures appeared to have leveled
off. The satellite and radar data also show a dry slot over the
southeastern quadrant.
Fred is over very warm waters of near 30 deg C and within a fairly
moist mid-level atmosphere. A little more strengthening is
possible prior to landfall, but significant southwesterly shear is
likely to limit strengthening. Also, the storm has little time
remaining over water. The latest official intensity forecast is
similar to the LGEM guidance.
Center fixes from the Hurricane Hunters and WSR-88D data from
Tallahassee and Eglin AFB indicate that Fred is a little east of the
previous track. It is not certain whether this is due to a slight
reformation of the center nearer to the strongest convection, but
that is certainly a possibility. Based on the most recent fixes,
the current motion estimate is just slightly east of north, or 010/9
kt. Fred is moving between the western side of a mid-level
subtropical high pressure area over the southwestern Atlantic and a
weak trough over the east-central United States. A slight bend of
the track toward the north-northeast with a little acceleration is
expected during the next couple of days. The official forecast is
just a bit to the east of the previous one, and follows the most
recent multi-model consensus.
Users are reminded not to focus on the exact forecast track of
Fred, since rainfall, storm surge, and wind hazards will extend
over an area well east of the center.
KEY MESSAGES:
1. Through Tuesday, heavy rainfall may lead to flash, urban, small
stream, and isolated river flooding impacts across the Southeast.
By the middle of the week as Fred lifts north and inland, heavy
rainfall and flooding will impact the southern and central
Appalachians, the Piedmont of the Southeast and Mid-Atlantic.
Landslides are possible across the mountains of North Carolina and
Blue Ridge Escarpment on Tuesday.
2. Dangerous storm surge inundation is expected along portions of
the coast of the Florida Panhandle and the Florida Big Bend region.
Preparations to protect life and property should be rushed to
completion in the Storm Surge Warning area.
3. Tropical storm conditions are occurring in the warning area and
will spread farther inland later today and tonight across portions
of the Florida Panhandle, southwestern Georgia, and southeastern
Alabama.
Tropical Storm Fred Discussion Number 24
NWS National Hurricane Center Miami FL AL062021
1100 AM EDT Sun Aug 15 2021
Satellite imagery and reports from an Air Force Reserve Hurricane
Hunter aircraft indicate that the remnants of Fred have
re-developed into a tropical cyclone over the eastern Gulf of
Mexico. Satellite imagery shows a well-defined low-level center
near the northern end of a broadly curved convective band. The
Hurricane Hunters reported a central pressure of 1008 mb, along
with 925-mb flight-level winds of 52 kt and SFMR wind estimates
near 35 kt about 70 n mi northeast of the center. Based on these
developments and data, the system was upgraded back to Tropical
Storm Fred a couple of hours ago.
The center re-formed northward during the redevelopment process,
and the initial position is re-located to the north of the previous
advisory position. While the forecast guidance is basically
unchanged in calling for a north-northwest motion followed by a
turn toward the north near landfall on the northern Gulf coast, the
new initial position requires the forecast track to be shifted about
40 n mi to the east of the previous track through the landfall time.
Fred is now expected to make landfall in the western Florida
Panhandle sometime Monday afternoon or evening.
Upper-level southwesterly flow between a trough to the north and
northwest of Fred and an anticyclone to the southeast of the storm
should keep the tropical cyclone in moderate southwesterly
vertical shear until landfall. The intensity guidance forecasts
gradual intensification before landfall, and the official intensity
forecast follows the guidance in calling for a peak intensity of
45 kt. After landfall, Fred should quickly weaken and dissipate as
it moves into the Tennessee Valley.
Users are reminded not to focus on the exact forecast track of
Fred, since rainfall, storm surge, and wind hazards will extend
over an area well east of the center.
KEY MESSAGES:
1. Today through Tuesday, heavy rainfall could lead to areal, urban,
small stream and river flooding impacts across southern Florida, the
Florida Big Bend and Panhandle, southern Alabama, portions of
Georgia, and the western Carolinas. From Tuesday onward, heavy rain
and flood impacts could continue 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. Dangerous storm surge inundation is possible along portions of
the coast of the Florida Panhandle, and a Storm Surge Warning has
been issued for this area. Interests in these areas should follow
any advice given by local officials.
3. Tropical storm conditions are expected in the Tropical Storm
Warning area in the Florida Panhandle beginning on Monday.
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