[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT42 KNHC 100233
TCDAT2

Tropical Storm Paulette Discussion Number  13
NWS National Hurricane Center Miami FL       AL172020
1100 PM AST Wed Sep 09 2020

Paulette remains a sheared tropical cyclone with the low-level
center southwest of a large area of deep convection.  Recent
scatterometer data showed peak winds of 45-50 kt, so 50 kt is used
as the initial wind speed, which happens to be quite similar to a
blend of the latest TAFB/SAB Dvorak estimates.   Paulette should
begin to weaken tomorrow and continue on a downward trend for 2-3
days as strong shear impacts the cyclone.  No change has been made
to the forecast through Saturday. Thereafter, the storm is likely to
move into a lower-shear environment on the northeastern side of a
mid/upper-level low, with SSTs rising to about 29C. There is better
agreement among the models tonight that Paulette will survive the
shear and be able to take advantage of that favorable environment.
In fact, almost all of the most reliable guidance, save LGEM/SHIPS,
show the storm becoming a hurricane by 120 hours, and the global
models are trending in that direction.  The new NHC forecast is
raised from the previous one, near the model consensus, but isn't
quite as high as the regional hurricane models.

The storm is moving at about the same motion as before (295/9 kt).
Paulette should turn westward tomorrow as it weakens and encounters
stronger low/mid-level ridging.  A weakness in the ridge develops by
the weekend due to the aforementioned mid/upper-level low, which
should cause the tropical cyclone to turn and move faster toward
the northwest. The new NHC track forecast is very similar to the
previous one, lying on the western side of the guidance after
placing heavier weight on the global models and corrected-consensus
aids than on the regional hurricane guidance.


FORECAST POSITIONS AND MAX WINDS

INIT  10/0300Z 20.9N  48.1W   50 KT  60 MPH
 12H  10/1200Z 21.3N  49.5W   50 KT  60 MPH
 24H  11/0000Z 21.4N  51.5W   45 KT  50 MPH
 36H  11/1200Z 21.9N  53.2W   40 KT  45 MPH
 48H  12/0000Z 22.8N  54.6W   40 KT  45 MPH
 60H  12/1200Z 24.1N  55.9W   40 KT  45 MPH
 72H  13/0000Z 25.8N  57.3W   45 KT  50 MPH
 96H  14/0000Z 29.0N  62.0W   55 KT  65 MPH
120H  15/0000Z 31.0N  65.0W   65 KT  75 MPH

$$
Forecaster Blake
This weather bulletin was brought to you by:
www.nashvilleweather.net