000 WTNT44 KNHC 110853 TCDAT4 HURRICANE HUMBERTO DISCUSSION NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092013 500 AM AST WED SEP 11 2013 CENTRAL CONVECTION HAS BEEN ON THE INCREASE WITH HUMBERTO DURING THE LAST FEW HOURS...WITH A LARGE CURVED BAND WRAPPING AROUND THE CYCLONE ALSO BECOMING BETTER DEFINED. THE DVORAK ESTIMATES AT 6Z SUPPORTED ANYTHING FROM 55-65 KT...AND GIVEN THE NOTABLE STRENGTHENING OF THE CENTRAL DEEP CONVECTION AND OVERALL INCREASE IN ORGANIZATION...THE INITIAL WINDS ARE RAISED TO 65 KT. HUMBERTO HAS ABOUT A DAY TO STRENGTHEN BEFORE AN INCREASE IN SHEAR AND COOLER WATERS SHOULD CAUSE A WEAKENING TREND. IN A FEW DAYS... ALTHOUGH WATER TEMPERATURES BEGIN TO RISE...STRONG WESTERLY SHEAR AND ENTRAINMENT OF DRIER AIR WILL PROBABLY KEEP THE CYCLONE GRADUALLY WEAKENING. THE INTENSITY GUIDANCE SEEMS TO BE WELL CLUSTERED...SO THE LATEST NHC WIND SPEED PREDICTION IS CLOSE TO THE PREVIOUS FORECAST AND THE MODEL CONSENSUS. HUMBERTO APPEARS TO BE TURNING TO THE RIGHT...NOW MOVING 330/7. THE CYCLONE SHOULD TURN TO THE NORTH SOON AND ACCELERATE SOME WHILE IT MOVES BETWEEN A RIDGE OVER NORTHWESTERN AFRICA AND A TROUGH OVER THE CENTRAL ATLANTIC OCEAN. IN A COUPLE OF DAYS...HUMBERTO IS LIKELY TO TAKE A HARD LEFT TURN DUE TO IT RUNNING AGAINST A RATHER STOUT RIDGE IN THE SUBTROPICAL EASTERN ATLANTIC. WITH HUMBERTO BECOMING A MORE SHALLOW SYSTEM IN THE LONGER RANGE...IT MAKES SENSE TO STAY ON THE SOUTHERN SIDE OF THE GUIDANCE ENVELOPE GIVEN THE STRONG LOW-LEVEL RIDGE FORECAST. THE LATEST NHC FORECAST IS BASICALLY AN UPDATE OF THE PREVIOUS ONE...STAYING EQUATORWARD OF THE MODEL CONSENSUS IN THE MEDIUM RANGE. FORECAST POSITIONS AND MAX WINDS INIT 11/0900Z 16.0N 28.9W 65 KT 75 MPH 12H 11/1800Z 17.2N 29.2W 70 KT 80 MPH 24H 12/0600Z 19.0N 29.3W 75 KT 85 MPH 36H 12/1800Z 20.9N 29.6W 70 KT 80 MPH 48H 13/0600Z 22.5N 30.3W 65 KT 75 MPH 72H 14/0600Z 23.8N 33.9W 50 KT 60 MPH 96H 15/0600Z 24.2N 39.1W 45 KT 50 MPH 120H 16/0600Z 25.5N 44.0W 40 KT 45 MPH $$ FORECASTER BLAKE