000 WTNT44 KNHC 211450 TCDAT4 TROPICAL DEPRESSION NINE DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012 1100 AM AST TUE AUG 21 2012 A BURST OF CONVECTION CONTINUES JUST SOUTH OR SOUTHWEST OF THE CENTER OF TROPICAL DEPRESSION NINE...ALTHOUGH THE OVERALL COVERAGE HAS DECREASED DURING THE PAST FEW HOURS. SATELLITE INTENSITY ESTIMATES ARE 35 KT FROM TAFB AND 30 KT FROM SAB. BASED ON THESE DATA AND THE RELATIVELY HIGH PRESSURE OF 1010 MB AT NOAA BUOY 41040...THE INITIAL INTENSITY REMAINS 30 KT. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT IS SCHEDULED TO INVESTIGATE THE DEPRESSION THIS AFTERNOON. THE INITIAL MOTION REMAINS 270/17. THE DEPRESSION IS LOCATED SOUTH OF A DEEP-LAYER SUBTROPICAL RIDGE THAT IS FORECAST TO REMAIN INTACT FOR THE NEXT 72 HR...WHICH SHOULD KEEP THE CYCLONE MOVING GENERALLY WESTWARD AS SHOWN BY THE TIGHTLY CLUSTERED TRACK MODEL GUIDANCE. AFTER THAT...THE GLOBAL MODELS ARE FORECASTING A SHORTWAVE TROUGH TO DIG SOUTHWARD OVER THE SOUTHEASTERN U.S. AND THE GULF OF MEXICO...WHICH IS EXPECTED TO WEAKEN THE RIDGE ACROSS FLORIDA AND THE BAHAMAS. THIS SHOULD ALLOW THE CYCLONE TO TURN WEST- NORTHWESTWARD AND SLOW DOWN ACROSS THE NORTH-CENTRAL CARIBBEAN SEA. THE GUIDANCE SHOWS MORE SPREAD DURING THIS PERIOD...WITH THE UKMET ON THE RIGHT EDGE SHOWING THE CYCLONE MOVING ALONG THE NORTHERN COAST OF HISPANIOLA...AND THE ECMWF AND GFS ON THE LEFT EDGE SHOWING THE SYSTEM PASSING SOUTH OF HISPANIOLA. THE NEW FORECAST TRACK IS SIMILAR TO THE PREVIOUS TRACK THROUGH 72 HR...THEN IS A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK AFTER THAT. THE TRACK IS IN BEST AGREEMENT WITH A BLEND OF THE GFS AND ECMWF MODELS. THE DEPRESSION IS CURRENTLY EXPERIENCING LIGHT/MODERATE NORTHEASTERLY VERTICAL WIND SHEAR. THIS SHOULD DIMINISH DURING THE NEXT 24 HR OR SO...LEAVING THE CYCLONE IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT. THE NEW INTENSITY FORECAST IS THE SAME AS THE PREVIOUS FORECAST THROUGH 72 HR...SHOWING THE SYSTEM BECOMING A TROPICAL STORM IN 12 HR AND A HURRICANE IN 48 HR. AFTER 72 HR...THE FORECAST TRACK BRINGS THE SYSTEM CLOSER TO HISPANIOLA AND CUBA THAN THE PREVIOUS TRACK. BASED ON THIS...THE INTENSITY FORECAST DURING THAT TIME HAS BEEN LOWERED BY 5-10 KT. FORECAST POSITIONS AND MAX WINDS INIT 21/1500Z 15.1N 52.8W 30 KT 35 MPH 12H 22/0000Z 15.2N 55.3W 35 KT 40 MPH 24H 22/1200Z 15.5N 58.4W 40 KT 45 MPH 36H 23/0000Z 15.9N 61.5W 50 KT 60 MPH 48H 23/1200Z 16.2N 64.6W 65 KT 75 MPH 72H 24/1200Z 17.0N 70.0W 80 KT 90 MPH 96H 25/1200Z 18.5N 74.0W 90 KT 105 MPH...INLAND 120H 26/1200Z 20.5N 77.5W 85 KT 100 MPH...OVER WATER $$ FORECASTER BEVEN