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Hurricane Gilma Discussion Number 31
NWS National Hurricane Center Miami FL EP072024
1100 AM HST Sun Aug 25 2024
GOES-18 satellite images indicate that Gilma's eye continues to
become more cloud-filled and less well-defined. Microwave images
from earlier this morning showed a better-defined eye at that time.
The latest subjective intensity estimates from TAFB and SAB are
T-5.5/102 kt. The UW-CIMSS objective intensity estimates have also
decreased from 6 hours ago, and range from about 77 to 104 kt. The
initial intensity has been lowered to 100 kt for this advisory,
based on a blend of the data.
A combination of dry environmental air and marginal SSTs are likely
the reasons why Gilma has weakened some today. Gilma should
continue to move over SSTs near or just above 26C for another 24 h
before it reaches slightly cooler waters. Gilma is still located
within an environment of low vertical wind shear but is forecast to
move into 15 kt of westerly vertical wind shear by early Monday
which is expected to cause the storm to weaken. The new NHC
intensity forecast is similar to the previous forecast and
is very near the intensity consensus aids. The forecast shows
steady weakening by about 15 kt per day. By day 4, Gilma should
move into an area of moderate to strong west-southwesterly vertical
wind shear, which should strip away any remaining convection.
Therefore, the forecast calls for Gilma to become a remnant low by
day 5.
Gilma has been moving due west over the past 12 h, or 270/9 kt. A
mid-tropospheric ridge should continue to steer Gilma between west
and west-northwest for the next several days. The NHC track
forecast is nearly on top of the previous prediction and is close
to a blend of the HCCA and TVCE consensus aids through 72 h. The
NHC forecast is slightly south of those consensus aids beyond 72 h.
FORECAST POSITIONS AND MAX WINDS
INIT 25/2100Z 18.0N 134.3W 100 KT 115 MPH
12H 26/0600Z 18.1N 135.7W 90 KT 105 MPH
24H 26/1800Z 18.3N 137.4W 85 KT 100 MPH
36H 27/0600Z 18.5N 139.1W 75 KT 85 MPH
48H 27/1800Z 18.7N 140.9W 70 KT 80 MPH
60H 28/0600Z 19.0N 142.7W 60 KT 70 MPH
72H 28/1800Z 19.4N 144.5W 55 KT 65 MPH
96H 29/1800Z 20.0N 147.9W 40 KT 45 MPH
120H 30/1800Z 20.6N 152.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
$$
Forecaster Hagen/Pasch
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