Tropical Storm JOYCE Advisory Wed Aug 22

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TROPICAL DEPRESSION TEN DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL102012
1100 AM AST WED AUG 22 2012

SATELLITE DATA INDICATE THAT THE LOW PRESSURE AREA LOCATED OVER THE
EASTERN TROPICAL ATLANTIC HAS DEVELOPED A WELL-DEFINED SURFACE
CIRCULATION AND SUFFICIENT CONVECTIVE ORGANIZATION TO BE DESIGNATED
AS A TROPICAL DEPRESSION. SATELLITE INTENSITY ESTIMATES FROM TAFB
AND SAB ARE BOTH 2.0...AND THE INITIAL INTENSITY IS SET AT 30KT.
GIVEN THE FAVORABLE UPPER-AIR ENVIRONMENT AHEAD OF THE DEPRESSION
DURING THE NEXT 2-3 DAYS...SOME INTENSIFICATION IS EXPECTED. AFTER
THAT TIME...THE INTENSITY WILL DEPEND IN LARGE PART ON HOW MUCH THE
DEPRESSION BECOMES INVOLVED WITH AN UPPER-LEVEL LOW NORTHEAST OF
THE LESSER ANTILLES IN ABOUT 3 DAYS AND THE INFLUENCE OF THE
UPPER-LEVEL OUTFLOW FROM TROPICAL STORM ISAAC LATE IN THE FORECAST
PERIOD.  INTERACTIONS WITH EITHER WOULD RESULT IN AN INCREASE OF
VERTICAL WIND SHEAR OVER THE CYCLONE AND A POSSIBLE HALT IN
INTENSIFICATION. FOR NOW...THE OFFICIAL FORECAST FOLLOWS THE
INTENSITY CONSENSUS AIDS.

THE INITIAL MOTION ESTIMATE IS 295/14.  THE DEPRESSION IS EXPECTED
TO CONTINUE MOVING WEST-NORTHWESTWARD...NEARLY IN TANDEM WITH A
MID- TO UPPER-LEVEL IMPULSE ON THE SOUTH SIDE OF A SUBTROPICAL
RIDGE OVER EASTERN/CENTRAL ATLANTIC. AFTER ABOUT 3 DAYS...THE
CYCLONE SHOULD TURN NORTHWESTWARD AS IT REACHES THE WESTERN
PERIPHERY OF THE SUBTROPICAL RIDGE. THE SPREAD IN THE TRACK
GUIDANCE INCREASES CONSIDERABLY BY THE END OF THE FORECAST
PERIOD...WITH THE GFS FORECASTING A DEEPER SYSTEM THAT TURNS
MORE QUICKLY.  THE HWRF SHOWS A SHALLOWER VORTEX THAT MOVES ON A
MORE WESTWARD TRACK. THE OFFICIAL FORECAST LIES BETWEEN THESE TWO
EXTREMES...CLOSE TO THE ECMWF AND THE MODEL CONSENSUS TVCA.


FORECAST POSITIONS AND MAX WINDS

INIT  22/1500Z 12.4N  36.3W   30 KT  35 MPH
 12H  23/0000Z 13.3N  38.1W   40 KT  45 MPH
 24H  23/1200Z 14.3N  40.8W   45 KT  50 MPH
 36H  24/0000Z 15.2N  43.6W   50 KT  60 MPH
 48H  24/1200Z 16.2N  46.3W   55 KT  65 MPH
 72H  25/1200Z 18.5N  52.0W   55 KT  65 MPH
 96H  26/1200Z 21.8N  58.0W   55 KT  65 MPH
120H  27/1200Z 26.0N  64.0W   60 KT  70 MPH

$$
FORECASTER KIMBERLAIN/ZELINSKY