000
WTPZ41 KNHC 160238
TCDEP1
 
TROPICAL DEPRESSION SIX-E DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP062011
800 PM PDT MON AUG 15 2011
 
THERE HAS BEEN LITTLE CHANGE IN THE ORGANIZATION OF THE DEPRESSION
DURING THE LAST SEVERAL HOURS. THE LOW-LEVEL CENTER REMAINS
DETACHED FROM A SINGLE CONVECTIVE BAND IN THE SOUTHERN
SEMICIRCLE...PRESUMABLY A SYMPTOM OF CONTINUED NORTHEASTERLY SHEAR.
THE INITIAL INTENSITY IS HELD AT 30 KT...BASED ON A BLEND OF
SATELLITE INTENSITY ESTIMATES FROM BOTH SAB AND TAFB.
 
GLOBAL MODELS STILL FORECAST THE VERTICAL SHEAR TO DECREASE DURING
THE NEXT COUPLE OF DAYS. ON THE OTHER HAND...THE CYCLONE WILL
GRADUALLY BE MOVING OVER MARGINALLY WARM WATERS AND WILL BEGIN TO
INGEST A RELATIVELY DRIER AND MORE STABLE AIR MASS FROM THE NORTH.
THE LATTER TWO FACTORS WOULD LIKELY OFFSET ANY POTENTIAL FOR
SIGNIFICANT INTENSIFICATION...ESPECIALLY GIVEN THE CURRENT
ORGANIZATION OF THE SYSTEM.  BETWEEN 48 AND 72 HOURS...AN ABRUPT
INCREASE IN SOUTHEASTERLY SHEAR AND SUB-26C WATERS SHOULD HASTEN THE
DEMISE OF THE TROPICAL CYCLONE.  THE OFFICIAL FORECAST IS ADJUSTED
DOWNWARD SLIGHTLY AND REMAINS A LITTLE BELOW THE INTENSITY
GUIDANCE. GIVEN THE INCREASINGLY HOSTILE ENVIRONMENTAL CONDITIONS
LATER IN THE FORECAST PERIOD...IT WOULD NOT BE SURPRISING TO SEE
THE CYCLONE DEGENERATE INTO A REMNANT LOW SOONER THAN WHAT IS
CURRENTLY INDICATED.
 
THE INITIAL MOTION ESTIMATE IS 270/8.  AN EAST-NORTHEAST TO
WEST-SOUTHWEST ORIENTED MID-LEVEL RIDGE NORTH OF THE DEPRESSION
SHOULD STEER IT ON A WESTWARD COURSE DURING THE NEXT DAY OR TWO.  BY
48 HOURS...A LONGWAVE TROUGH DEVELOPING BETWEEN 130W AND 140W
SHOULD CAUSE A BREAK IN THE RIDGE. HOWEVER...GIVEN THE WEAK NATURE
OF THE CYCLONE AT THAT POINT...THE EFFECTS OF THE TROUGH ARE
EXPECTED TO MINIMAL AND A MORE WESTERLY MOTION IS ASSUMED LATER IN
THE FORECAST PERIOD.  THE OFFICIAL TRACK REMAINS ON THE SOUTHERN
SIDE OF THE GUIDANCE ENVELOPE AND IS BASED PRIMARILY ON A BLEND OF
THE PREVIOUS NHC TRACK AND THE UKMET/ECWMF MODELS.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  16/0300Z 12.2N 133.0W   30 KT  35 MPH
 12H  16/1200Z 12.2N 134.0W   30 KT  35 MPH
 24H  17/0000Z 12.3N 135.5W   35 KT  40 MPH
 36H  17/1200Z 12.4N 137.1W   40 KT  45 MPH
 48H  18/0000Z 12.7N 138.5W   40 KT  45 MPH
 72H  19/0000Z 13.5N 141.6W   30 KT  35 MPH
 96H  20/0000Z 14.0N 145.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  21/0000Z 13.5N 150.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
 
$$
FORECASTER KIMBERLAIN