000
WTPZ41 KNHC 171458
TCDEP1
TROPICAL STORM COSME DISCUSSION NUMBER  13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP062007
800 AM PDT TUE JUL 17 2007
 
DURING THE LAST SIX HOURS...BOTH MICROWAVE AND CONVENTIONAL
SATELLITE IMAGERY INDICATE THAT THE CLOUD PATTERN HAS QUICKLY
DETERIORATED.  TRMM AND AMSR-E OVERPASSES FROM 1018 UTC AND 1056
UTC RESPECTIVELY SHOW THAT THE LOW-LEVEL CENTER IS EXPOSED WITH THE
REMAINING DEEP CONVECTION LOCATED ABOUT 60-75 N MI TO THE WEST.
THE INITIAL INTENSITY HAS BEEN CONSERVATIVELY LOWERED TO 40 KT.
THIS IS MUCH LOWER THAN SATELLITE INTENSITY ESTIMATES...WHICH ARE
BEING CONSTRAINED DUE TO DVORAK WEAKENING RULES.
 
BASED ON THE 1018 UTC TRMM PASS...THE CENTER WAS RELOCATED TO THE
EAST-SOUTHEAST AND THE MOTION...ALBEIT UNCERTAIN...IS NOW 280/10.
THE FORECAST TRACK REASONING REMAINS VIRTUALLY THE SAME...COSME IS
EXPECTED TO MAINTAIN A GENERAL WEST TO WEST-NORTHWESTWARD MOTION
THROUGH FIVE DAYS UNDER THE INFLUENCE OF A STRONG RIDGE TO THE
NORTH.  ONCE AGAIN THE MODEL GUIDANCE IS CLUSTERED...AND THE
OFFICIAL TRACK FORECAST BRINGS COSME NEAR OR OVER THE HAWAIIAN
ISLANDS IN 4-5 DAYS.
 
BOTH COOL WATERS AND EASTERLY SHEAR ARE ANTICIPATED TO CONTINUE TO
INFLUENCE THE CYCLONE'S INTENSITY...ESPECIALLY DURING THE NEXT 24
TO 36 HOURS.  THE SHIPS GUIDANCE ACTUALLY DISSIPATES COSME IN TWO
DAYS...WHILE THE GFDL AND HWRF HOLD ON TO THE SYSTEM AS A TROPICAL
STORM THROUGH DAY FIVE.  THE OFFICIAL INTENSITY FORECAST MAINTAINS
COSME AS A WEAK TROPICAL STORM THROUGH 4 DAYS.   HOWEVER IF THE
CURRENT RAPID WEAKENING TREND CONTINUES...SOME ADDITIONAL DOWNWARD
ADJUSTMENTS WILL NEED TO BE MADE.
  
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      17/1500Z 15.1N 134.4W    40 KT
 12HR VT     18/0000Z 15.4N 136.1W    35 KT
 24HR VT     18/1200Z 15.8N 138.4W    35 KT
 36HR VT     19/0000Z 16.2N 141.0W    35 KT
 48HR VT     19/1200Z 16.7N 143.9W    35 KT
 72HR VT     20/1200Z 18.0N 150.0W    35 KT
 96HR VT     21/1200Z 19.0N 155.5W    35 KT
120HR VT     22/1200Z 19.0N 160.0W    30 KT
 
$$
FORECASTER MAINELLI