ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM HUMBERTO DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092013 500 AM AST TUE SEP 10 2013 HUMBERTO CONTINUES TO STEADILY STRENGTHEN. SATELLITE IMAGES INDICATE THAT THE ASSOCIATED BANDING FEATURES HAVE BECOME BETTER ORGANIZED AND MORE SYMMETRIC AROUND THE CENTER...INDICATING THAT VERTICAL WIND SHEAR IS DECREASING OVER THE CYCLONE. DVORAK CLASSIFICATIONS FROM TAFB AND SAB WERE BOTH T3.5 AND UW-CIMSS ADT VALUES ARE ABOUT THE SAME. BASED ON THESE ESTIMATES...THE INITIAL WIND SPEED IS INCREASED TO 55 KT. THE TROPICAL STORM IS GRADUALLY TURNING TO THE RIGHT...AND THE LATEST INITIAL MOTION ESTIMATE IS 295/8. A TURN TO THE NORTHWEST IS EXPECTED TODAY...FOLLOWED BY A NORTHWARD MOTION ON WEDNESDAY. THIS ABRUPT CHANGE IN THE FORECAST STORM MOTION IS DUE TO A BREAK DOWN OF THE SUBTROPICAL RIDGE THAT WILL BE CAUSED BY A MID- TO UPPER-LEVEL LOW MOVING SOUTHWARD OVER THE CENTRAL ATLANTIC AND ANOTHER LOW BETWEEN THE CANARY ISLANDS AND THE AZORES. A SHARP WESTWARD TURN IS FORECAST TO OCCUR IN ABOUT 4 DAYS WHEN THE RIDGE BECOMES RE-ESTABLISHED. THE NHC TRACK FORECAST IS IN FAIR AGREEMENT GIVEN THE PRONOUNCED HEADING CHANGES...AND THE LATEST OFFICIAL FORECAST IS CLOSE TO THE MULTI-MODEL CONSENSUS TVCA. THE INTENSIFICATION TREND IS EXPECTED TO CONTINUE FOR ANOTHER 36 HOURS WHILE HUMBERTO REMAINS OVER WARM WATER AND WITHIN AN ENVIRONMENT OF LOW WIND SHEAR AND HIGH MID-LEVEL MOISTURE. AFTER THAT TIME...THE GLOBAL MODELS SHOW DRIER AIR AND SOUTHERLY TO SOUTHWESTERLY SHEAR AFFECTING HUMBERTO. THESE UNFAVORABLE ATMOSPHERIC CONDITIONS COMBINED WITH COOLER SSTS SHOULD CAUSE THE SYSTEM TO BEGIN WEAKENING IN A COUPLE OF DAYS. THE NHC INTENSITY FORECAST IS NEAR THE HIGH END OF THE MODEL GUIDANCE IN THE SHORT TERM AND IS BASICALLY AN UPDATE OF THE PREVIOUS PACKAGE. FORECAST POSITIONS AND MAX WINDS INIT 10/0900Z 14.4N 26.6W 55 KT 65 MPH 12H 10/1800Z 15.0N 27.5W 65 KT 75 MPH 24H 11/0600Z 16.2N 28.3W 75 KT 85 MPH 36H 11/1800Z 17.9N 28.8W 85 KT 100 MPH 48H 12/0600Z 20.0N 29.1W 85 KT 100 MPH 72H 13/0600Z 23.7N 30.0W 75 KT 85 MPH 96H 14/0600Z 25.5N 32.5W 55 KT 65 MPH 120H 15/0600Z 26.0N 36.5W 45 KT 50 MPH $$ FORECASTER CANGIALOSI NNNN