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#1059189 (Received by flhurricane at: 5:08 AM 29.Aug.2021)
TCDAT1

Tropical Depression Eleven Discussion Number 2
NWS National Hurricane Center Miami FL AL112021
500 AM AST Sun Aug 29 2021

The depression continues to slowly organize this morning, with a
distinct curved band stretching along the southeastern quadrant of
the low-level circulation. However, the deep convection that was
closer to the center earlier has recently been sheared off to the
northeast due to increasing southwesterly vertical wind shear. The
latest subjective Dvorak estimates from TAFB and SAB were T2.0/30
kt and T1.5/25 kt respectively. The latest objective ADT guidance
was a bit higher at T2.4/34 kt. Taking a blend of these estimates,
the intensity was held at 30 kt for this advisory, though the
depression appears close to becoming a tropical storm.

The depression is beginning to gradually accelerate, with the
estimated motion now at 050/13 kt. A strong deep-layer trough will
continue to steer the depression to the northeast in the short-term
with increasing forward motion. After the system becomes a
post-tropical cyclone, it is forecast to gradually pivot to the
north and then northwest before dissipating in 72 hours. The latest
NHC track forecast is a touch faster than the previous one,
following the latest consensus track guidance.

While vertical wind shear is expected to increase quite dramatically
over the next 24-36 hours, strong baroclinic forcing should offset
this negative factor and allow at least steady intensification in
the short term especially as the cyclone accelerates. After 24
hours, the system will be crossing into much cooler sea-surface
temperatures, and extratropical transition will likely be ongoing as
the system merges with an advancing frontal boundary. The latest NHC
intensity forecast follows the HCCA consensus aid closely, and is
just a bit stronger in the short-term helped by the fast forward
motion, with a peak intensity of 50-kt just before extratropical
transition occurs.


FORECAST POSITIONS AND MAX WINDS

INIT 29/0900Z 34.0N 48.6W 30 KT 35 MPH
12H 29/1800Z 35.8N 45.6W 40 KT 45 MPH
24H 30/0600Z 38.5N 41.3W 50 KT 60 MPH
36H 30/1800Z 41.8N 37.7W 50 KT 60 MPH...POST-TROP/EXTRATROP
48H 31/0600Z 45.9N 36.0W 45 KT 50 MPH...POST-TROP/EXTRATROP
60H 31/1800Z 50.0N 36.7W 40 KT 45 MPH...POST-TROP/EXTRATROP
72H 01/0600Z...DISSIPATED

$$
Forecaster Papin