TROPICAL STORM SANDY DISCUSSION NUMBER   6
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL182012
500 PM EDT TUE OCT 23 2012

SATELLITE IMAGES CONTINUE TO SHOW FAIRLY WELL-DEFINED CONVECTIVE
BANDING FEATURES...MAINLY OVER THE EASTERN PORTION OF THE
CIRCULATION OF THE STORM.  THE CENTER OF SANDY IS ESTIMATED TO BE
LOCATED NEAR THE WESTERN EDGE OF A DEVELOPING CENTRAL DENSE
OVERCAST FEATURE...WHICH IS INDICATIVE OF A BIT OF WESTERLY SHEAR
OVER THE SYSTEM.  HOWEVER...THE ATMOSPHERIC AND OCEANIC ENVIRONMENT
IS EXPECTED TO FAVOR STRENGTHENING DURING THE NEXT DAY OR TWO WITH
LAND INTERACTION BEING THE PRIMARY IMPEDIMENT.  BY 72 HOURS...
SOUTH-SOUTHWESTERLY SHEAR IS EXPECTED TO INCREASE TO MORE THAN 30
KT AND THIS SHOULD LIMIT STRENGTHENING.  THE OFFICIAL INTENSITY
FORECAST IS A BLEND OF THE LATEST STATISTICAL-DYNAMICAL SHIPS AND
LGEM GUIDANCE.  BY THE END OF THE PERIOD...GLOBAL MODEL FORECASTS
SUGGEST THAT THE CYCLONE WILL BE DERIVING SOME ENERGY FROM
BAROCLINIC SOURCES AND THE OFFICIAL FORECAST SHOWS POST-TROPICAL
STATUS AT DAY 5.
THE INITIAL MOTION IS ESTIMATED TO BE SLOWLY NORTH-NORTHEASTWARD...
OR 020/5.  NO SIGNIFICANT CHANGES HAVE BEEN MADE TO THE PREVIOUS
TRACK FORECAST.  AS A MID-TROPOSPHERIC RIDGE TO THE NORTH OF SANDY
CONTINUES TO WEAKEN...THE TROPICAL CYCLONE SHOULD MOVE ON A
NORTH-NORTHEASTWARD TO NORTHWARD HEADING WITH SOME INCREASE IN
FORWARD SPEED OVER THE NEXT COUPLE OF DAYS.  IN 2-3 DAYS...A SHARP
UPPER-LEVEL TROUGH JUST TO WEST OF SANDY IS EXPECTED TO KEEP THE
STORM ON A NORTHWARD TRACK...NEAR THE NORTHWEST BAHAMAS.  LATER IN
THE FORECAST PERIOD...INCREASING MID-LEVEL WESTERLY FLOW IS
EXPECTED TO CAUSE A TURN TOWARD THE NORTHEAST.  THE OFFICIAL
FORECAST TRACK IS SIMILAR TO THE LATEST GFS AND ECMWF SOLUTIONS
THROUGH 72 HOURS...AND CLOSE TO THE DYNAMICAL MODEL CONSENSUS.
THE FORECAST TRACK AND EXPANDING WIND RADII SUGGEST THAT A TROPICAL
STORM WATCH COULD BE REQUIRED FOR PORTIONS OF SOUTHEASTERN FLORIDA
AND THE KEYS AS EARLY AS TONIGHT.

FORECAST POSITIONS AND MAX WINDS

INIT  23/2100Z 14.3N  77.6W   45 KT  50 MPH
12H  24/0600Z 15.7N  77.3W   55 KT  65 MPH
24H  24/1800Z 17.9N  77.1W   65 KT  75 MPH
36H  25/0600Z 20.3N  76.9W   70 KT  80 MPH...INLAND
48H  25/1800Z 22.8N  76.9W   60 KT  70 MPH...OVER WATER
72H  26/1800Z 26.3N  76.7W   60 KT  70 MPH
96H  27/1800Z 29.5N  73.5W   60 KT  70 MPH
120H  28/1800Z 32.0N  69.0W   60 KT  70 MPH...POST-TROPICAL

$$
FORECASTER PASCH