WTNT42 KNHC 312043
HURRICANE GASTON DISCUSSION NUMBER 37
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072016
500 PM AST WED AUG 31 2016
The satellite presentation of Gaston has gradually decayed today,
with the eye becoming more ragged in infrared imagery. The initial
intensity estimate is 90 kt based on a blend of the latest Dvorak
Final-T and CI numbers from TAFB and SAB. Steady weakening is
expected during the next few days while SSTs decrease steadily along
the forecast track and the shear increases above 20 kt by 48 hours.
The new NHC intensity forecast has been adjusted downward and is
close to the latest intensity model consensus, and now shows Gaston
weakening to a tropical storm as it approaches the Azores on Friday.
Gaston should lose tropical characteristics by 72 hours and
dissipate by 96 hours as shown by the global models.
The initial motion estimate is 055/16, and Gaston is expected to
move east-northeastward to eastward in the mid-latitude westerlies
through dissipation. The NHC track forecast is a little north of
the previous one and is along the middle of the guidance envelope
but faster than the TVCN consensus, trending toward the faster FSU
Based on the new forecast, a tropical storm watch has been issued
for portions of the western and central Azores.
FORECAST POSITIONS AND MAX WINDS
INIT 31/2100Z 35.0N 46.9W 90 KT 105 MPH
12H 01/0600Z 36.3N 44.0W 85 KT 100 MPH
24H 01/1800Z 37.7N 39.5W 75 KT 85 MPH
36H 02/0600Z 38.5N 34.8W 65 KT 75 MPH
48H 02/1800Z 39.0N 30.8W 55 KT 65 MPH
72H 03/1800Z 41.0N 25.0W 35 KT 40 MPH...POST-TROPICAL