755 
 WTNT41 KNHC 301432
 TCDAT1
  
 TROPICAL STORM JERRY DISCUSSION NUMBER   7
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112013
 1100 AM AST MON SEP 30 2013
 
 DEEP CONVECTION HAS BECOME MORE PERSISTENT...AND VISIBLE SATELLITE
 IMAGES INDICATE THAT THE LOW-LEVEL CENTER IS NEAR THE WESTERN EDGE
 OF THE MAIN AREA OF CONVECTION.  DVORAK INTENSITY ESTIMATES FROM
 TAFB AND SAB ARE BOTH 35 KT...AND THE CYCLONE IS BEING UPGRADED TO
 A TROPICAL STORM ON THIS ADVISORY.  WATER VAPOR IMAGERY SHOWS
 DIFFLUENT UPPER-LEVEL FLOW OVER THE AREA...HOWEVER THE DYNAMICAL
 GUIDANCE INDICATES THAT WESTERLY TO NORTHWESTERLY VERTICAL SHEAR
 SHOULD CONTINUE TO AFFECT THE STORM FOR THE NEXT SEVERAL DAYS.  AT
 THIS TIME...THE ENVIRONMENT IS NOT EXPECTED TO BE HOSTILE ENOUGH TO
 PREVENT AT LEAST A LITTLE STRENGTHENING DURING THE NEXT DAY OR SO. 
 IN THE LATTER PART OF THE FORECAST PERIOD...THERE IS QUITE A BIT OF
 SPREAD IN THE NUMERICAL INTENSITY GUIDANCE...AND THEREFORE THE WIND
 SPEED FORECAST FOR THAT TIME IS OF LOW CONFIDENCE.
 
 CENTER FIXES FROM VISIBLE SATELLITE IMAGES INDICATE THAT THE STORM
 HAS MOVED A LITTLE MORE TO THE EAST THAN EARLIER ESTIMATED...AND
 THE INITIAL MOTION IS NEAR 090/6.  THE DYNAMICAL MODELS CONTINUE TO
 PREDICT AN AMPLIFYING MID-TROPOSPHERIC RIDGE TO THE NORTHWEST AND
 NORTH OF JERRY OVER THE NEXT SEVERAL DAYS.  THIS STEERING SCENARIO
 SHOULD RESULT IN THE STORM DECELERATING AND MOVING IN A CLOCKWISE
 LOOP DURING THE NEXT 48-72 HOURS...AS SHOWN IN THE OFFICIAL TRACK
 FORECAST.  IN THE LATTER PART OF THE PERIOD...THE GLOBAL MODELS ARE
 SUGGESTING THAT JERRY MAY NOT GET PICKED UP BY THE NEXT TROUGH IN
 THE WESTERLIES...AND THIS IS ALSO REFLECTED IN THE CURRENT OFFICIAL
 FORECAST. 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  30/1500Z 27.0N  45.7W   35 KT  40 MPH
  12H  01/0000Z 26.6N  45.5W   35 KT  40 MPH
  24H  01/1200Z 26.3N  45.5W   40 KT  45 MPH
  36H  02/0000Z 26.2N  46.5W   40 KT  45 MPH
  48H  02/1200Z 26.3N  47.9W   40 KT  45 MPH
  72H  03/1200Z 27.3N  49.8W   40 KT  45 MPH
  96H  04/1200Z 28.5N  49.0W   35 KT  40 MPH
 120H  05/1200Z 30.5N  46.0W   35 KT  40 MPH
  
 $$
 FORECASTER PASCH