000
WTPZ43 KNHC 012032
TCDEP3
TROPICAL STORM ERICK DISCUSSION NUMBER   5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP082007
200 PM PDT WED AUG 01 2007
 
VISIBLE SATELLITE IMAGERY INDICATES THAT STRONG EASTERLY SHEAR
IS TAKING ITS TOLL ON ERICK...WITH THE LOW LEVEL CIRCULATION NOW
ALMOST COMPLETELY EXPOSED ON THE NORTHEAST SIDE OF A WEAKENING BLOB
OF DEEP CONVECTION.  WHILE THE SATELLITE SIGNATURE IS SUGGESTIVE OF
A WEAKENING CYCLONE...THE INITIAL INTENSITY IS CONSERVATIVELY HELD
AT 35 KT TO SEE IF THE CURRENT CONVECTIVE TREND PERSISTS. GIVEN THE
CYCLONE IS CURRENTLY OVER SSTS OF ABOUT 28C...SOME STRENGTHENING
REMAINS POSSIBLE IF THE SHEAR DECREASES.  HOWEVER...SSTS START
APPROACHING 26C IN 48 HOURS AND THE THERMODYNAMIC ENVIRONMENT
APPEARS MARGINAL. IT WOULD APPEAR THAT ANY STRENGTHENING THAT DOES
OCCUR WOULD NEED TO HAPPEN SOONER RATHER THAN LATER. 
ACCORDINGLY...THE OFFICIAL FORECAST ALLOWS FOR A LITTLE
STRENGTHENING IN THE SHORT-TERM FOLLOWED BY SLOW WEAKENING.  
 
BASED ON LATEST VISIBLE IMAGERY...THE LOW LEVEL CIRCULATION IS
MOVING A LITTLE TO THE RIGHT OF THE PREVIOUS FORECAST TRACK OR
ABOUT 285/9. ASSUMING THE SYSTEM CAN MAINTAIN SOME VERTICAL
DEPTH...A MID-LEVEL RIDGE TO THE NORTH IS EXPECTED TO BE
THE PRIMARY STEERING MECHANISM OVER THE NEXT SEVERAL DAYS.
THEREFORE ERICK SHOULD CONTINUE ON A GENERAL WEST-NORTHWESTWARD
HEADING FOR MOST OF THE FORECAST PERIOD.  TRACK GUIDANCE CONTINUES
TO TREND NORTHWARD AND SO DOES THE OFFICIAL FORECAST. 

THE 34 KT WIND RADII WERE ADJUSTED BASED ON THE LATEST QUIKSCAT DATA
THAT INDICATES TROPICAL STORM FORCE WINDS ARE CONFINED TO THE
SOUTHWEST QUADRANT. 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      01/2100Z 13.6N 127.1W    35 KT
 12HR VT     02/0600Z 13.7N 128.4W    35 KT
 24HR VT     02/1800Z 13.9N 130.0W    40 KT
 36HR VT     03/0600Z 14.2N 131.5W    45 KT
 48HR VT     03/1800Z 14.4N 133.3W    45 KT
 72HR VT     04/1800Z 14.7N 136.8W    45 KT
 96HR VT     05/1800Z 15.0N 139.5W    40 KT
120HR VT     06/1800Z 15.0N 143.0W    40 KT
 
$$
FORECASTER RHOME