WTNT42 KNHC 260851 RRA

TCDAT2



TROPICAL STORM GASTON DISCUSSION NUMBER  15

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016

500 AM AST FRI AUG 26 2016



GASTON IS RIGHT IN THE THICK OF 20-25 KT OF SOUTHWESTERLY SHEAR,

AND THE LOW-LEVEL CENTER APPEARS TO BE NEAR OR JUST INSIDE THE

SOUTHERN EDGE OF A RAGGED CENTRAL DENSE OVERCAST.  BECAUSE DVORAK

CURRENT INTENSITY ESTIMATES FROM TAFB AND SAB REMAIN 3.5, THE

INITIAL INTENSITY IS HELD AT 55 KT.  WITH GASTON NOW MOVING AROUND

THE NORTHEASTERN SIDE OF A MID- TO UPPER-LEVEL LOW, THE VERTICAL

SHEAR IS EXPECTED TO QUICKLY DECREASE TO BELOW 10 KT WITHIN THE NEXT

12-24 HOURS.  IN ADDITION, SEA SURFACE TEMPERATURES ARE FORECAST TO

INCREASE BY ANOTHER DEGREE OR TWO.  THEREFORE, GASTON IS LIKELY TO

BEGIN STRENGTHENING LATER TODAY, AND IT SHOULD REINTENSIFY TO A

HURRICANE BY TONIGHT OR ON SATURDAY.  STRENGTHENING IS ANTICIPATED

TO CONTINUE THROUGH DAYS 3 AND 4, WITH GASTON NEARING OR POSSIBLY

REACHING MAJOR HURRICANE INTENSITY, FOLLOWED BY SOME WEAKENING ON

DAY 5 DUE TO AN INCREASE IN WESTERLY SHEAR.  THE RELIABLE INTENSITY

MODELS ARE ALL WITHIN 10-15 KT OF EACH OTHER FOR THE ENTIRE

FORECAST PERIOD, AND THE NHC FORECAST IS THEREFORE VERY CLOSE TO

THE ICON INTENSITY CONSENSUS.



GASTON CONTINUES TO MOVE NORTHWESTWARD, OR 320 DEGREES AT 15 KT.

THE CYCLONE IS EXPECTED TO MAINTAIN A GENERALLY NORTHWESTWARD TRACK

BUT SLOW DOWN CONSIDERABLY DURING THE NEXT FEW DAYS AFTER IT MOVES

NORTH OF THE AFOREMENTIONED MID- TO UPPER-LEVEL LOW AND ENTERS A

BREAK IN THE SUBTROPICAL RIDGE.  AFTER 72 HOURS, GASTON IS EXPECTED

TO REACH THE MID-LATITUDE WESTERLIES, AND A SHARP RECURVATURE WITH=