000 WTPZ42 KNHC 231445 TCDEP2 TROPICAL STORM BUD DISCUSSION NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL EP022012 800 AM PDT WED MAY 23 2012 RECENT 0843 UTC AMSU-B AND 1055 UTC SSMI MICROWAVE OVERPASSES SHOW THAT BUD HAS A WELL-DEFINED CENTER ENCIRCLED BY A RING OF DEEP CONVECTION...SO IT WOULD SEEM THAT THE CYCLONE IS FINALLY STRENGTHENING. DVORAK ESTIMATES FROM TAFB AND SAB ARE 55 AND 45 KT...RESPECTIVELY. THE UW-CIMSS ADT IS GIVING A CURRENT INTENSITY OF ABOUT 50 KT...BUT IT APPEARS TO BE ASSUMING A CENTER TOO FAR TO THE EAST. IN ADDITION...A COUPLE OF AMSU ESTIMATES SUGGEST AN INTENSITY NEAR HURRICANE STRENGTH. THE INITIAL INTENSITY IS THEREFORE RAISED TO 55 KT AS A CONSENSUS OF THE VARIOUS ESTIMATES. BUD IS MOVING NORTHWESTWARD...OR 310/8 KT...INTO A WEAKNESS IN THE SUBTROPICAL RIDGE OVER NORTHWESTERN MEXICO. THE CYCLONE IS FORECAST TO SLOW DOWN AND TURN NORTHEASTWARD OVER THE NEXT 36 HOURS DUE TO A DEEPENING LONGWAVE TROUGH OVER THE WESTERN UNITED STATES. HOWEVER...A MID-LEVEL HIGH IS ALSO EXPECTED TO BUILD OVER THE LOWER MISSISSIPPI VALLEY...AND THAT FEATURE SHOULD CAUSE BUD TO STALL OFF THE MEXICAN COAST BY 72 HOURS. THE MODEL GUIDANCE IS IN GENERALLY GOOD AGREEMENT...ALTHOUGH THE ECMWF MODEL ENDS UP A LITTLE CLOSER TO THE MEXICAN COAST ON DAY 3. THE NHC FORECAST IS CLOSE TO THE MODEL CONSENSUS AND IS SHIFTED A LITTLE WEST OF THE PREVIOUS FORECAST ONLY DURING THE FIRST 24 TO 36 HOURS. NEEDLESS TO SAY...THE INTENSITY FORECAST FOR BUD HAS BEEN DIFFICULT. BECAUSE THE CYCLONE IS NOW STRENGTHENING...THE NHC INTENSITY FORECAST REQUIRES AN UPWARD ADJUSTMENT AND AGAIN BRINGS BUD TO HURRICANE STRENGTH. AS OPPOSED TO PREVIOUS DAYS...THE SHIPS AND LGEM MODELS ARE IN GOOD AGREEMENT AND SHOW THE CYCLONE PEAKING NEAR 70-75 KT IN 24-36 HOURS...AND THIS APPEARS REASONABLE GIVEN AN ENVIRONMENT OF LOW VERTICAL SHEAR AND WARM SEA SURFACE TEMPERATURES. WEAKENING IS EXPECTED AFTER DAY 2 DUE TO INCREASING SOUTHERLY WIND SHEAR AND POSSIBLE INGESTION OF DRIER AIR FROM THE WEST INTO THE CYCLONE CIRCULATION. THE NHC FORECAST ON DAYS 3 THROUGH 5 CLOSELY FOLLOWS THE GRADUAL WEAKENING INDICATED BY THE LGEM. THE POTENTIAL FOR TROPICAL-STORM-FORCE WINDS AT LOCATIONS ON THE SOUTHWESTERN COAST OF MEXICO HAS NOT DECREASED...AND INTERESTS IN THAT AREA SHOULD CONTINUE TO MONITOR THE PROGRESS OF THE SYSTEM. FORECAST POSITIONS AND MAX WINDS INIT 23/1500Z 13.4N 107.6W 55 KT 65 MPH 12H 24/0000Z 14.0N 108.1W 65 KT 75 MPH 24H 24/1200Z 14.7N 108.1W 75 KT 85 MPH 36H 25/0000Z 15.7N 107.4W 70 KT 80 MPH 48H 25/1200Z 16.8N 106.8W 65 KT 75 MPH 72H 26/1200Z 18.0N 106.5W 50 KT 60 MPH 96H 27/1200Z 17.5N 106.5W 40 KT 45 MPH 120H 28/1200Z 17.0N 108.0W 30 KT 35 MPH $$ FORECASTER BERG