[Tropical] Tropical Cyclone Discussion

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WTNT43 KNHC 062037
TCDAT3

Potential Tropical Cyclone Thirteen Discussion Number   2
NWS National Hurricane Center Miami FL       AL132022
500 PM AST Thu Oct 06 2022

The disturbance is gradually becoming better organized, with some
convective banding attempting to form west of the center during the
past several hours.  Radar imagery from Curacao also suggests there
could be a better-defined center trying to form just to the south
of Bonaire and Curacao, but there are not enough nearby surface
observations to confirm that.  Therefore, the system is not yet
designated as a tropical depression.  However, an Air Force
Reserve Hurricane Hunter aircraft scheduled for a survey mission
later this evening should hopefully give us a better sense of the
wind field and help provide evidence if the system has developed a
well-defined circulation.

The track forecast is straightforward.  The disturbance is being
driven quickly westward with a motion of 270/15 kt by a strong low-
to mid-level ridge stretching across the western Atlantic and Gulf
of Mexico.  This feature should maintain the system on a westward
heading for the next 3 days across the southwestern Caribbean Sea,
with some slowing of the forward motion as it moves away from the
main high center over the western Atlantic.  A slight turn toward
the west-northwest across Central America is forecast by day 4 once
the system, or its remnants, reaches the western periphery of the
ridge.  The track models remain tightly clustered, and the new NHC
forecast is near the previous prediction and the TVCN/HCCA
consensus aids.

The system is likely to form a well-defined center and become a
tropical cyclone within the next 6-12 hours, which is generally
shown by the various global models.  They, along with
statistical-dynamical guidance, indicate the system should also
begin to gradually strengthen while passing near the Guajira
Peninsula of Colombia.  Once the system reaches the southwestern
Caribbean Sea, low to moderate shear and warm sea surface
temperatures of 29 to 30 degrees Celsius should foster faster
strengthening, and a consensus of the various SHIPS Rapid
Intensification (RI) indices indicates a 65-75 percent chance of a
65-kt increase over the next 3 days.  The NHC intensity is not yet
that aggressive, but the peak intensity now shown in the official
forecast is raised a bit higher to 75 kt at 60 and 72 hours.  It's
possible that the intensity could get a little higher between those
times before the system reaches land.  Based on the forecast track,
the system is unlikely to survive a trek across the terrain of
Central America, and dissipation is therefore shown by day 5.


Key Messages:

1. Tropical storm conditions are expected across portions of the
Guajira Peninsula of Colombia tonight and early Friday, 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 could be required for
portions of these areas tonight or on Friday

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


FORECAST POSITIONS AND MAX WINDS

INIT  06/2100Z 11.6N  68.7W   30 KT  35 MPH...POTENTIAL TROP CYCLONE
 12H  07/0600Z 12.0N  70.7W   35 KT  40 MPH...TROPICAL STORM
 24H  07/1800Z 12.6N  73.6W   40 KT  45 MPH
 36H  08/0600Z 13.0N  76.7W   50 KT  60 MPH
 48H  08/1800Z 13.0N  79.6W   60 KT  70 MPH
 60H  09/0600Z 13.1N  81.9W   75 KT  85 MPH
 72H  09/1800Z 13.3N  84.1W   75 KT  85 MPH...INLAND
 96H  10/1800Z 14.8N  89.1W   35 KT  40 MPH...INLAND
120H  11/1800Z...DISSIPATED

$$
Forecaster Berg
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