000
WTPZ43 KNHC 121448
TCDEP3
 
TROPICAL STORM HECTOR DISCUSSION NUMBER   5
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP082012
800 AM PDT SUN AUG 12 2012
 
HECTOR IS A STRONGLY SHEARED TROPICAL STORM. CONVENTIONAL SATELLITE
AND MICROWAVE DATA INDICATE THAT THE LOW-LEVEL CENTER IS EXPOSED TO
THE EAST OF A LARGE AREA OF DEEP CONVECTION DUE TO ABOUT 20 KT OF
EASTERLY SHEAR. DVORAK CLASSIFICATIONS FROM TAFB AND SAB WERE BOTH
45 KT AT 1200 UTC...BUT GIVEN THE POOR STRUCTURE OF THE SYSTEM IN
EARLY MORNING VISIBLE IMAGES...THE INITIAL WIND SPEED IS HELD AT 40
KT. ALTHOUGH HECTOR IS OVER WARM WATER...THE INFLUENCE OF EASTERLY
SHEAR SHOULD PREVENT THE STORM FROM STRENGTHENING SIGNIFICANTLY.
THE MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT IN ONLY SHOWING
MODEST STRENGTHENING FOR THE NEXT 2 TO 3 DAYS. THE OFFICIAL
FORECAST DURING THAT TIME PERIOD CLOSELY FOLLOWS THE LGEM AND
INTENSITY MODEL CONSENSUS. BEYOND A FEW DAYS...HECTOR IS EXPECTED
TO CROSS THE 26C ISOTHERM AND WILL BE MOVING OVER PROGRESSIVELY
COLDER WATERS AFTER THAT. THEREFORE...STEADY WEAKENING IS
ANTICIPATED AFTER DAY 3.
 
SATELLITE FIXES AND A SSMIS OVERPASS AT 1140 UTC SUGGEST THAT HECTOR
WAS LOCATED A LITTLE TO THE SOUTH OF THE PREVIOUS TRACK. THE
INITIAL MOTION...ALBEIT UNCERTAIN...IS 270/9. HECTOR IS FORECAST TO
CONTINUE MOVING WESTWARD WITH SOME REDUCTION IN FORWARD
SPEED OVER THE NEXT 24 TO 36 HOURS AS IT REMAINS TO THE SOUTH OF A
MID-LEVEL HIGH OVER THE SOUTHWESTERN UNITED STATES.  A TURN TO THE
WEST-NORTHWEST IS PREDICTED AFTER 36 HOURS AS THE RIDGE TO THE
NORTHEAST OF HECTOR WEAKENS DUE TO A DEVELOPING MID- TO UPPER-LEVEL
LOW OFF THE CALIFORNIA COASTLINE. THE OFFICIAL FORECAST IS ADJUSTED
SOUTHWARD FROM THE PREVIOUS ONE DUE TO THE INITIAL MOTION AND
POSITION AND TO COME INTO BETTER AGREEMENT WITH THE LATEST MODEL
GUIDANCE.
  
FORECAST POSITIONS AND MAX WINDS
 
INIT  12/1500Z 18.3N 110.0W   40 KT  45 MPH
 12H  13/0000Z 18.3N 111.1W   45 KT  50 MPH
 24H  13/1200Z 18.2N 112.0W   45 KT  50 MPH
 36H  14/0000Z 18.3N 113.0W   50 KT  60 MPH
 48H  14/1200Z 18.7N 114.1W   55 KT  65 MPH
 72H  15/1200Z 19.4N 116.0W   55 KT  65 MPH
 96H  16/1200Z 20.3N 118.0W   45 KT  50 MPH
120H  17/1200Z 21.0N 120.5W   35 KT  40 MPH
 
$$
FORECASTER CANGIALOSI