004 
 WTNT44 KNHC 242034
 TCDAT4
 TROPICAL STORM DEBBY DISCUSSION NUMBER  13
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL042006
 500 PM EDT THU AUG 24 2006
  
 SATELLITE IMAGERY INDICATES THAT THERE HAS BEEN LITTLE OVERALL
 CHANGE IN DEBBY DURING THE LAST SEVERAL HOURS. ACCORDINGLY...THE
 INITIAL INTENSITY IS UNCHANGED AT 45 KT. IT WOULD APPEAR THAT
 SOUTHERLY SHEAR CONTINUES OVER THE CYCLONE WITH THE DEEPEST
 CONVECTION DISPLACED A LITTLE NORTH OF THE ESTIMATED CENTER. 
 ADDITIONALLY...DEBBY IS EXHIBITING A BURSTING TYPE PATTERN IN ITS
 CONVECTIVE EVOLUTION.  SINCE THE SHEAR IS NOT EXPECTED TO WEAKEN
 SIGNIFICANTLY IN THE SHORT-TERM...ONLY GRADUAL STRENGTHENING IS
 SHOWN DURING THE FIRST 2 DAYS.  THE UPPER FLOW MAY BECOME A BIT
 MORE CONDUCIVE FOR STRENGTHENING THEREAFTER.  THE BEST CHANCE FOR
 THIS SYSTEM TO BECOME A HURRICANE MAY NOT COME UNTIL IT NEARS A
 MID-LATITUDE TROUGH THAT IS EXPECTED TO DIG SOUTHWARD OVER THE
 CENTRAL ATLANTIC AT DAYS 4 AND 5.  THIS SAME TROUGH IS ALSO
 EXPECTED TO RESULT IN DEBBY'S EXTRATROPICAL TRANSITION BY DAY 5. 
 THE ONLY CHANGE TO THE OFFICIAL INTENSITY FORECAST IS TO DELAY
 STRENGTHENING TO A HURRICANE BY ONE DAY. 
  
 THE INITIAL MOTION ESTIMATE IS 300/7. DEBBY SHOULD CONTINUE ON A
 GENERAL NORTHWESTWARD MOTION FOR THE NEXT COUPLE OF DAYS AS IT
 MOVES AROUND THE SOUTHWESTERN PERIPHERY OF A MID-LEVEL ANTICYCLONE
 NEAR THE AZORES. THEREAFTER...THE CYCLONE IS EXPECTED TO TURN NORTH
 INTO A WEAKNESS WITHIN THE SUBTROPICAL RIDGE...THEN ACCELERATE
 NORTHEASTWARD AHEAD OF A MID-LATITUDE TROUGH FORECAST TO DIG
 SOUTHWARD OVER THE CENTRAL ATLANTIC. THERE HAS BEEN NO SIGNIFICANT
 CHANGE TO THE TRACK GUIDANCE...WHICH REMAINS IN GOOD AGREEMENT...
 AND ONLY COSMETIC CHANGES TO THE OFFICIAL TRACK FORECAST.  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      24/2100Z 21.3N  39.5W    45 KT
  12HR VT     25/0600Z 22.3N  41.9W    45 KT
  24HR VT     25/1800Z 23.8N  44.9W    45 KT
  36HR VT     26/0600Z 25.4N  47.4W    50 KT
  48HR VT     26/1800Z 27.1N  49.5W    55 KT
  72HR VT     27/1800Z 30.9N  51.3W    55 KT
  96HR VT     28/1800Z 35.0N  49.0W    65 KT
 120HR VT     29/1800Z 40.1N  44.0W    65 KT...EXTRATROPICAL
  
 $$
 FORECASTER RHOME/FRANKLIN