000 WTNT41 KNHC 221452 TCDAT1 TROPICAL DEPRESSION SIX DISCUSSION NUMBER 4 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062010 1100 AM AST SUN AUG 22 2010 THE UPWARD TREND IN ORGANIZATION OF THE DEPRESSION APPEARS TO HAVE STOPPED FOR THE TIME BEING. THE SYSTEM HAS A WELL-DEFINED CENTER...BUT THE CIRCULATION IS A LITTLE STRETCHED FROM NORTHEAST TO SOUTHWEST DUE TO ANOTHER DISTURBANCE LOCATED ABOUT 350 N MI TO THE NORTHEAST. THIS HAS ALSO CAUSED THE CENTER TO MOVE ALMOST DUE NORTH OVER THE PAST FEW HOURS...PULLING IT FARTHER AWAY FROM THE DEEP CONVECTION. SATELLITE INTENSITY ESTIMATES ARE 30 KT AND 45 KT FROM SAB AND TAFB...RESPECTIVELY...AND AN 1134 UTC ASCAT PASS SHOWED A MAXIMUM OF 30 KT. THE INITIAL INTENSITY WILL BE KEPT AT 30 KT SINCE THERE HAS BEEN LITTLE CHANGE IN ORGANIZATION. WITH THE RECENT NORTHWARD MOTION...THE SMOOTHED INITIAL MOTION IS ROUGHLY 310/10. ONCE THE DEPRESSION ESCAPES THE INFLUENCE OF THE DISTURBANCE TO ITS NORTHEAST...THE SUBTROPICAL RIDGE CENTERED ALONG 26N SHOULD STEER THE CYCLONE GENERALLY WEST-NORTHWESTWARD WITH INCREASING FORWARD SPEED THROUGH THE NEXT 72 HOURS. BY DAYS 4 AND 5 THERE IS GREATER UNCERTAINTY WITH THE TRACK FORECAST DEPENDING ON HOW THE MID-LATITUDE LONGWAVE PATTERN EVOLVES IN RELATION TO WHEN THE DEPRESSION ACTUALLY BEGINS MOVING WESTWARD. THE GLOBAL MODEL GUIDANCE IS IN GOOD AGREEMENT SHOWING AN AMPLIFYING TROUGH NEAR 45W BY DAY 4...WHICH SHOULD BE TOO FAR EAST TO INDUCE SIGNIFICANT RECURVATURE. THIS PATTERN...HOWEVER...SHOULD CAUSE THE SYSTEM TO SLOW DOWN A LITTLE BY DAYS 4 AND 5 AS IT BECOMES TRAPPED TO THE SOUTH OF A MID-LEVEL RIDGE. THE OFFICIAL FORECAST HAS BEEN SHIFTED A LITTLE SOUTH AND WEST BY DAY 5...VERY CLOSE TO THE GFS...GFDL ...AND HWRF MODELS...AND LIES A LITTLE TO THE RIGHT OF THE MODEL CONSENSUS TVCN. THE DEPRESSION IS EXPECTED TO REMAIN UNDER THE INFLUENCE OF MODERATE EAST-NORTHEASTERLY SHEAR FOR THE NEXT 24 HOURS OR SO...BUT THEREAFTER THE UPPER-LEVEL ENVIRONMENT BECOMES MORE CONDUCIVE FOR STRENGTHENING. HOWEVER...THE SYSTEM MAY STILL HAVE TO CONTEND WITH DRY AND RELATIVELY STABLE AIR TO ITS NORTH AS IT MOVES ACROSS THE ATLANTIC...AND MOST OF THE INTENSITY GUIDANCE NOW SHOWS A SLOWER RATE OF INTENSIFICATION. THE OFFICIAL FORECAST HAS BEEN NUDGED DOWN A LITTLE FROM THE PREVIOUS FORECAST BUT IS STILL HIGHER THAN EVERY INTENSITY MODEL AT DAY 5 EXCEPT FOR THE GFDL. BASED ON AN EXPERIMENTAL INTENSITY PROBABILITY PRODUCT AT NHC...THE DEPRESSION CURRENTLY HAS A 1 IN 5 CHANCE OF REACHING MAJOR HURRICANE STATUS AT SOME POINT OVER THE NEXT FIVE DAYS. FORECAST POSITIONS AND MAX WINDS INITIAL 22/1500Z 12.7N 34.1W 30 KT 12HR VT 23/0000Z 13.0N 35.6W 35 KT 24HR VT 23/1200Z 13.8N 38.1W 40 KT 36HR VT 24/0000Z 14.7N 40.8W 50 KT 48HR VT 24/1200Z 15.9N 43.7W 60 KT 72HR VT 25/1200Z 19.0N 49.0W 70 KT 96HR VT 26/1200Z 22.0N 53.0W 80 KT 120HR VT 27/1200Z 24.5N 56.0W 85 KT $$ FORECASTER BERG