105
WTNT43 KNHC 220231
TCDAT3

Tropical Storm Melissa Discussion Number 3
NWS National Hurricane Center Miami FL AL132025
1100 PM EDT Tue Oct 21 2025

Melissa continues to be under the influence of significant westerly
vertical wind shear. The center of the storm appears to be exposed
to the west of a cluster of very deep convection, and overall the
system is not very well organized with poorly-defined banding
features. The advisory intensity is held at 45 kt in agreement
with a Dvorak classification from TAFB, though objective intensity
estimates from UW-CIMSS are somewhat lower. An Air Force Reserve
Unit Hurricane Hunter aircraft is scheduled to investigate the
tropical cyclone in a few hours and should provide a good intensity
estimate. Melissa remains an asymmetric storm with most of the
strong winds over the northeastern and eastern portions of the
circulation.

The system continues to move a little southwest of the previous
track with an initial motion estimate of 270/11 kt. The track
forecast for the next several days remains quite challenging.
Melissa is likely to remain in a region of weak steering currents
for most of this week. Once again, the GFS model looks like an
outlier with a track across Hispaniola by this weekend and most of
the other guidance much farther south and west. The future track
depends, among other things, on how strong and vertically deep
Melissa will become while it is over the Caribbean, and how much a
mid-level trough digs along the U.S. east coast during the next
5 days. A stronger tropical cyclone would likely move more
northward or northeastward than a weak system would. The new
official forecast is shifted somewhat west of the previous one and
is in good agreement with the dynamical model consensus and the FSU Superensemble solution. The latest Google DeepMind ensemble mean is
just a little to the left of the official forecast.

Water vapor imagery continues to show upper-level westerlies ahead
of Melissa, and the shear is not likely to decrease much over the
next few days. The SHIPS guidance using the large-scale predictors
from the ECMWF model indicates some relaxation of the shear in 3-5
days. The official intensity forecast, like the previous one,
shows strengthening into a hurricane by the latter part of the
forecast period. This is in good agreement with the LGEM guidance.
However it should be noted that this is a low-confidence intensity
forecast.

Key Messages:

1. Melissa is expected to produce heavy rainfall across portions of
the Dominican Republic, Haiti, and Jamaica through this weekend,
bringing a risk of significant flash flooding and landslides.

2. Hurricane conditions are possible in the southwestern peninsula
of Haiti where a Hurricane Watch is in effect. A Tropical Storm
Watch is in effect for Jamaica. Preparations to protect life and
property should be completed by Thursday.

3. There is significant uncertainty in the track and intensity
forecast of Melissa. Interests elsewhere in Hispaniola and Cuba
should continue to monitor the latest forecasts.


FORECAST POSITIONS AND MAX WINDS

INIT 22/0300Z 14.2N 74.0W 45 KT 50 MPH
12H 22/1200Z 14.6N 74.6W 45 KT 50 MPH
24H 23/0000Z 15.1N 75.2W 50 KT 60 MPH
36H 23/1200Z 15.6N 75.6W 55 KT 65 MPH
48H 24/0000Z 15.9N 75.8W 55 KT 65 MPH
60H 24/1200Z 16.3N 75.8W 60 KT 70 MPH
72H 25/0000Z 16.9N 75.7W 60 KT 70 MPH
96H 26/0000Z 17.5N 76.1W 65 KT 75 MPH
120H 27/0000Z 17.6N 76.2W 75 KT 85 MPH

$$
Forecaster Pasch


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