Issued at 1100 AM EDT MON MAY 21 2012
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
