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Tropical Storm Melissa Discussion Number   6
NWS National Hurricane Center Miami FL       AL142019
500 PM AST Sat Oct 12 2019

Convection has continued to persist near the center of Melissa
throughout the day, and only in the past few hours have the affects
of increasing westerly shear begun to erode the convection from the
western side of the cyclone.  A pair of scatterometer passes late
this morning showed that the wind field associated with the storm
had contracted, with the strongest winds occurring within 50 n mi of
the center. They also revealed that the radius of maximum winds had
decreased to 20 n mi.  Based on these data along with a tropical
structure apparent in satellite and microwave data, it is likely
that Melissa completed a transition to a tropical cyclone at some
point this morning.  A recent Dvorak classification from TAFB, an
objective estimate from UW-CIMSS ADT, and an earlier scatterometer
pass all support an initial intensity of 45 kt for this advisory.

The westerly shear beginning to affect Melissa is expected to
gradually increase over the next few days. Through tonight, the
cyclone will move over waters of 23-24 C. In addition, the upper
trough over the storm that has aided in maintaining its convection
will weaken and lift northeast of the cyclone over the next day or
so. The combination of these factors should cause Melissa to weaken,
and the cyclone is forecast to become a post-tropical remnant low by
Sunday.  The global model intensity forecasts appear to be
capturing the strongest winds in a frontal zone well-removed to the
northeast of Melissa and not directly associated with the cyclone
itself. Thus, the NHC forecast is very similar to the previous one,
and continues to be lower than the global model guidance.

Melissa is moving east-northeastward, or 070/10 kt. The increasing
westerly flow will cause the cyclone to gradually accelerate through
Monday. This motion will continue, with a slight turn to the east in
a few days, just before the cyclone is absorbed by a frontal zone.
The new NHC track forecast is close to the previous one and in the
middle of the various consensus aids.

Ongoing hazards from coastal flooding will continue to be covered by
non-tropical products from local National Weather Service forecast
offices.

Key Messages:

1. Although Melissa is forecast to weaken and move away from the
east coast, minor to moderate coastal flooding is still expected
along portions of the U.S. Mid-Atlantic and southeastern coasts
around times of high tide for the remainder of the weekend. For more
information, see products issued by local National Weather Service
forecast offices at weather.gov.


FORECAST POSITIONS AND MAX WINDS

INIT  12/2100Z 38.4N  65.6W   45 KT  50 MPH
 12H  13/0600Z 39.0N  63.5W   35 KT  40 MPH
 24H  13/1800Z 39.8N  60.0W   30 KT  35 MPH...POST-TROP/REMNT LOW
 36H  14/0600Z 40.7N  55.9W   30 KT  35 MPH...POST-TROP/REMNT LOW
 48H  14/1800Z 41.6N  51.6W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  15/1800Z 42.4N  39.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  16/1800Z...ABSORBED BY A FRONTAL ZONE

$$
Forecaster Latto

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