WTNT42 KNHC 282034
HURRICANE GASTON DISCUSSION NUMBER 25
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072016
500 PM AST SUN AUG 28 2016
The 15 n mi diameter eye has become more distinct on visible
satellite images today, and enhanced IR images show a cooling of the
cloud tops surrounding the eye. These features indicate
strengthening, and the current intensity is increased to 100 kt in
agreement with the subjective Dvorak estimates from TAFB and SAB, as
well as objective ADT numbers from UW-CIMSS. Upper-level outflow is
well-established both to the west and the east of the hurricane.
Based on a consensus of the intensity models, not much additional
strengthening is anticipated. When Gaston moves to a little higher
latitude, westerly shear on the system should increase, and steady
weakening is expected to commence in about 48 hours.
Gaston continues to crawl northwestward while being partially
blocked by a narrow mid-level subtropical ridge. The hurricane is
forecast to work its way through the ridge over the next day or so.
By Tuesday, an east-northeastward motion with gradual acceleration
is likely as the system begins to feel the effect of the
mid-latitude westerlies. The official forecast track is shifted a
little southward late in the forecast period, in line with the
latest global model guidance.
FORECAST POSITIONS AND MAX WINDS
INIT 28/2100Z 30.8N 55.1W 100 KT 115 MPH
12H 29/0600Z 31.0N 55.5W 100 KT 115 MPH
24H 29/1800Z 31.4N 55.5W 100 KT 115 MPH
36H 30/0600Z 32.0N 54.4W 95 KT 110 MPH
48H 30/1800Z 32.8N 52.6W 95 KT 110 MPH
72H 31/1800Z 34.9N 47.7W 85 KT 100 MPH
96H 01/1800Z 37.5N 40.5W 75 KT 85 MPH
120H 02/1800Z 37.5N 33.5W 60 KT 70 MPH