[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT41 KNHC 141441
TCDAT1

Tropical Storm Josephine Discussion Number  12
NWS National Hurricane Center Miami FL       AL112020
1100 AM AST Fri Aug 14 2020

Morning visible satellite imagery indicates that the center of
Josephine is located to the south or southwest of the strongest area
of convection, likely due to the onset of southwesterly vertical
wind shear.  A just-received scatterometer pass supports an initial
intensity of 35 kt, but also suggests the possibility that the
circulation is longer closed.  An Air Force Reserve Hurricane Hunter
aircraft is scheduled to investigate Josephine this afternoon to
provide more information on the intensity and whether a closed
circulation still exists.

The initial motion continues west-northwestward or 295/14 kt.
Josephine should continue this general motion as it approaches a
weakness in the subtropical ridge in 48-60 h.  Then, the cyclone
should turn northward and move through the weakness in 72-96 h.
Late in the forecast period, Josephine or its remnants are expected
to turn north-northeastward along the southern edge of the
higher-latitude westerlies.  The track guidance has not changed
significantly since the previous advisory, and the new NHC forecast
track is very similar to the previous forecast.

Southwesterly to westerly shear should markedly increase after
12-18 h due mainly to upper-level troughing over the southwestern
Atlantic.  The new intensity forecast leaves open the possibility of
a little strengthening during the next 12 h, followed by weakening
due to the shear.  The intensity forecast follows the previous
forecast showing the system decaying to a remnant low by 120 h.
However, an alternative scenario, supported by several of the global
models, is that the cyclone decays to a tropical wave well before
that time.

Josephine should pass far enough to the northeast of the Leeward
Islands over the weekend to prevent major impacts.  However,
interests in the area should continue to monitor its progress until
the storm has passed north of that area.


FORECAST POSITIONS AND MAX WINDS

INIT  14/1500Z 16.1N  54.7W   35 KT  40 MPH
 12H  15/0000Z 17.1N  56.7W   40 KT  45 MPH
 24H  15/1200Z 18.4N  59.3W   40 KT  45 MPH
 36H  16/0000Z 19.7N  61.8W   40 KT  45 MPH
 48H  16/1200Z 20.9N  64.1W   35 KT  40 MPH
 60H  17/0000Z 22.5N  66.0W   35 KT  40 MPH
 72H  17/1200Z 24.0N  67.0W   30 KT  35 MPH
 96H  18/1200Z 27.0N  67.5W   30 KT  35 MPH
120H  19/1200Z 30.6N  65.5W   25 KT  30 MPH...POST-TROP/REMNT LOW

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