000
WTNT41 KNHC 212036
TCDAT1
 
TROPICAL STORM ALBERTO DISCUSSION NUMBER   9
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL012012
500 PM EDT MON MAY 21 2012
 
DATA FROM AN AIR FORCE HURRICANE HUNTER AIRCRAFT CONFIRM THAT
ALBERTO IS STILL A TROPICAL STORM.  MAXIMUM SFMR-OBSERVED SURFACE
WINDS WERE 37 KT AND PEAK 1000 FT FLIGHT-LEVEL WINDS WERE 39 KT.  IT
SHOULD ALSO BE NOTED THAT SEVERAL YACHTS FROM THE VOLVO OCEAN RACE
HAVE BEEN SAILING NOT FAR FROM...OR THROUGH...THE CENTER OF
ALBERTO...AND HAVE ALSO MEASURED WINDS OF TROPICAL STORM FORCE.
ONE OF THE YACHTS MEASURED A PRESSURE VERY CLOSE TO THE ESTIMATED
CENTRAL PRESSURE OF THE STORM.  THE CLOUD PATTERN IS BECOMING
INCREASINGLY SHEARED WITH THE LOW-LEVEL CENTER NOW EXPOSED TO THE
SOUTHWEST OF THE DEEP CONVECTION.  A CONTINUED INCREASE IN VERTICAL
SHEAR IS FORECAST BY THE GLOBAL MODELS...AND THIS SHOULD RESULT IN
ALBERTO WEAKENING TO DISSIPATION IN ABOUT 2 DAYS.  GLOBAL
MODELS...HOWEVER...SUGGEST THAT THE CYCLONE COULD DISSIPATE SOONER
THAN THAT.
 
ALBERTO CONTINUES TO MOVE EASTWARD...OR 080/7.  THERE IS ESSENTIALLY
NO CHANGE TO THE TRACK FORECAST FROM THE PREVIOUS ADVISORY.  AN
AMPLIFYING MID-LEVEL TROUGH TO THE WEST OF THE TROPICAL CYCLONE
SHOULD CAUSE THE SYSTEM TO ACCELERATE NORTHEASTWARD OVER THE NEXT
COUPLE OF DAYS.  THE OFFICIAL FORECAST IS AN EXTENSION OF THE
PREVIOUS ONE AND IS MORE OR LESS IN THE MIDDLE OF THE DYNAMICAL
TRACK MODEL GUIDANCE.  THIS FORECAST TRACK KEEPS THE COMPACT
CYCLONE WELL OFFSHORE OF THE U.S. EAST COAST. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  21/2100Z 30.5N  77.9W   35 KT  40 MPH
 12H  22/0600Z 31.7N  76.4W   35 KT  40 MPH
 24H  22/1800Z 33.4N  74.3W   30 KT  35 MPH
 36H  23/0600Z 35.4N  71.7W   30 KT  35 MPH
 48H  23/1800Z 37.5N  69.0W   25 KT  30 MPH...POST-TROP/EXTRATROP
 72H  24/1800Z...DISSIPATED
 
$$
FORECASTER PASCH