000 WTNT41 KNHC 211449 TCDAT1 TROPICAL STORM ALBERTO DISCUSSION NUMBER 8 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012012 1100 AM EDT MON MAY 21 2012 ALBERTO CONTINUES TO GENERATE SOME DEEP CONVECTION...BUT THE CLOUD PATTERN OF THE STORM IS BEGINNING TO BECOME ELONGATED EAST- NORTHEASTWARD...WHICH IS INDICATIVE OF INCREASING SHEAR. THE CURRENT INTENSITY IS HELD AT 35 KT FOR THIS ADVISORY...ALTHOUGH DVORAK ESTIMATES SUGGEST A SLIGHTLY LOWER VALUE. AN AIR FORCE HURRICANE HUNTER AIRCRAFT SHOULD PROVIDE A BETTER ESTIMATE OF THE STRENGTH OF ALBERTO. GLOBAL MODEL PREDICTIONS SHOW A SUBSTANTIAL INCREASE IN SHEAR OVER THE NEXT 48 HOURS AND THIS...ALONG WITH DRY AIR SEEN IN WATER VAPOR IMAGERY...SHOULD LEAD TO WEAKENING AND DISSIPATION IN 2-3 DAYS. THE OFFICIAL WIND SPEED FORECAST IS SIMILAR TO THAT FROM THE PREVIOUS ADVISORY AND IS CLOSE TO THE LGEM GUIDANCE. IT IS CERTAINLY POSSIBLE THAT ALBERTO COULD BECOME A POST-TROPICAL CYCLONE IN 48 HOURS. THE TROPICAL CYCLONE HAS TURNED TOWARD THE EAST...AND THE MOTION IS NOW ABOUT 090/6. THERE IS LITTLE CHANGE TO THE TRACK FORECAST AND REASONING FROM THE PREVIOUS ADVISORY. AN AMPLIFYING MID-LEVEL TROUGH TO THE WEST OF ALBERTO SHOULD ACCELERATE THE SYSTEM TOWARD THE NORTHEAST OVER THE NEXT 48 HOURS. THE OFFICIAL FORECAST IS VERY CLOSE TO THE PREVIOUS NHC FORECAST TRACK AND ROUGHLY IN THE MIDDLE OF THE DYNAMICAL MODEL GUIDANCE. THIS TRACK KEEPS THE SMALL CYCLONE WELL OFFSHORE OF THE U.S. EAST COAST. FORECAST POSITIONS AND MAX WINDS INIT 21/1500Z 30.4N 78.8W 35 KT 40 MPH 12H 22/0000Z 31.0N 77.5W 35 KT 40 MPH 24H 22/1200Z 32.5N 75.4W 35 KT 40 MPH 36H 23/0000Z 34.3N 73.2W 30 KT 35 MPH 48H 23/1200Z 36.3N 70.8W 30 KT 35 MPH 72H 24/1200Z...DISSIPATED $$ FORECASTER PASCH