[Tropical] Tropical Cyclone Discussion

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WTNT43 KNHC 070236
TCDAT3

Tropical Depression Thirteen Discussion Number   3
NWS National Hurricane Center Miami FL       AL132022
1100 PM AST Thu Oct 06 2022

Earlier satellite imagery and radar data from Curacao indicated
that the disturbance was developing a better-defined center between
the ABC Islands and the coast of Venezuela.  Since that time, a
large convective burst has formed near and just south of the
center, and there has been an increase in banding in the Curacao
radar data.  Based on these developments, the disturbance now has
sufficient circulation and organized convection to be designated a
tropical depression.  Reports from an Air Force Reserve Hurricane
Hunter aircraft surveying the system showed 25-30 kt winds north of
the center, so the initial intensity is set at 30 kt.

The track forecast remains straightforward.  The depression is
moving westward or 280/13 kt due to a strong low- to mid-level
ridge stretching across the western Atlantic and Gulf of Mexico.
This feature should maintain the system on a general westward
heading for the next 72 h across the southwestern Caribbean Sea,
with some slowing of the forward motion expected by 60-72 h as the
cyclone moves over Nicaragua and nears the western end of the ridge.
A subsequent turn toward the west-northwest across Central America
is forecast by 96 h.  The new track forecast is basically an update
of the previous forecast and lies very close to the tightly
clustered consensus models.

While the system has developed a better-defined circulation, the
strongest winds are currently well to the north of the center.
Given this and an environment of light northerly shear, the
intensity forecast shows gradual strengthening for the next 12 h,
with the cyclone becoming a tropical storm as it passes near the
Guajira Peninsula of Colombia.  After that, a faster rate of
development is expected as the cyclone's structure improves and the
shear gradually decreases.  The new intensity forecast calls for
the system to become a hurricane by 48 h and to reach a peak
intensity of 75 kt just before landfall in Nicaragua.  This could
be conservative, as the rapid intensification indices of the SHIPS
model show a significant chance of rapid intensification after 48
h. As mentioned in the last advisory, after landfall the system is
unlikely to survive the forecasted trek across the terrain of
Central America, and dissipation is therefore shown by 120 h.


Key Messages:

1. Tropical storm conditions are expected across portions of the
Guajira Peninsula of Colombia later tonight and Friday morning,
where a Tropical Storm Warning has been issued.  Gusts to tropical
storm force are possible across portions of northern Venezuela,
Aruba, Curacao, and Bonaire through early Friday.

2. The system is expected to strengthen when it moves over the
southwestern Caribbean Sea, and a Hurricane Watch is in effect for
San Andres, Providencia, and Santa Catalina Islands.  Interests in
Nicaragua and Honduras should also monitor the system's progress,
and additional watches or warnings are likely to be required for
portions of these areas on Friday.

3. Heavy rainfall could cause life-threatening flash flooding over
portions of the Guajira Peninsula, northern Venezuela, and the
island chain of Aruba, Bonaire, and Curacao during the next day or
two.  The potential for flash flooding and mudslides is expected to
spread to portions of Central America this weekend.


FORECAST POSITIONS AND MAX WINDS

INIT  07/0300Z 11.9N  69.8W   30 KT  35 MPH
 12H  07/1200Z 12.4N  72.0W   35 KT  40 MPH
 24H  08/0000Z 13.0N  75.0W   45 KT  50 MPH
 36H  08/1200Z 13.2N  78.0W   55 KT  65 MPH
 48H  09/0000Z 13.2N  80.7W   65 KT  75 MPH
 60H  09/1200Z 13.3N  83.1W   75 KT  85 MPH
 72H  10/0000Z 13.9N  85.4W   45 KT  50 MPH...INLAND
 96H  11/0000Z 15.5N  90.0W   30 KT  35 MPH...INLAND
120H  12/0000Z...DISSIPATED

$$
Forecaster Beven
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