581 
 WTNT42 KNHC 010245
 TCDAT2
  
 TROPICAL STORM PHILIPPE DISCUSSION NUMBER  28
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172011
 1100 PM AST FRI SEP 30 2011
  
 A PAIR OF MICROWAVE PASSES FROM LATE THIS AFTERNOON WERE VERY
 HELPFUL IN FIXING THE CENTER OF PHILIPPE AFTER THE CENTER BECAME
 OBSCURED...AND INDICATED THE CYCLONE WAS A LITTLE TO THE RIGHT OF
 THE PREVIOUS TRACK.  THE INITIAL MOTION IS 320/8.  THE MICROWAVE
 DATA ALSO SHOWED A VERY WELL-DEFINED LOW-LEVEL CONVECTIVE
 RING...BUT THE CURRENT INFRARED DEPICTION SUGGESTS THAT UPPER-LEVEL
 NORTHWESTERLY FLOW FROM OPHELIA IS BEGINNING TO TAKE A TOLL. 
 DVORAK INTENSITY ESTIMATES FROM TAFB AND SAB WERE 45 AND 35
 KT...RESPECTIVELY...AND THE ADVISORY INTENSITY IS HELD AT 45 KT.
 
 WATER VAPOR IMAGERY AND GLOBAL MODEL FORECASTS SUGGEST THAT THE
 NORTHWESTERLY SHEAR WILL LIKELY EXCEED 40 KT OVER THE NEXT COUPLE
 OF DAYS...SUCH THAT PHILIPPE COULD WELL SUFFER A BEHEADING AT THE
 HANDS OF OPHELIA.  THE LGEM...TRADITIONALLY THE BEST INTENSITY
 GUIDANCE...SHOWS A SLOW DECREASE IN STRENGTH AND THE OFFICIAL
 FORECAST IS IN GOOD AGREEMENT WITH THIS MODEL.  THE REMAINING
 GUIDANCE IS INEXPLICABLY INDIFFERENT TO THE SHEAR AND SHOWS LITTLE
 NET CHANGE IN STRENGTH.  NEAR THE END OF THE FORECAST PERIOD...
 SHOULD PHILIPPE SURVIVE...THE SHEAR IS EXPECTED TO LESSEN
 AND SO THE OFFICIAL FORECAST SHOWS A LITTLE STRENGTHENING AT THAT
 TIME. 
 
 A MID-LEVEL RIDGE IN BETWEEN THE TWO TROPICAL CYCLONES IS EXPECTED
 TO TURN PHILIPPE TO THE WEST-NORTHWEST AND PERHAPS WEST OVER THE
 NEXT COUPLE OF DAYS.  HOWEVER...THE STRENGTH OF THIS TURN WILL
 DEPEND ON HOW MUCH CONVECTION PHILIPPE CAN MAINTAIN AS THE
 NORTHWESTERLY SHEAR INCREASES...WITH A WEAKER OR SHALLOWER SYSTEM
 MAINTAINING A NORTHWARD COMPONENT OF MOTION LONGER.  BY DAY
 FOUR...PHILIPPE SHOULD BE APPROACHING A LARGE TROUGH OFF THE U.S.
 EAST COAST AND TURN NORTHWARD.  MODEL GUIDANCE DIVERGES
 SIGNIFICANTLY AT THAT POINT...WITH THE ECMWF AND UKMET SHOWING
 PHILIPPE TURNING NORTHEASTWARD AND THE GFS MUCH FARTHER SOUTHWEST. 
 THE OFFICIAL FORECAST HAS BEEN ADJUSTED TO THE RIGHT OF THE
 PREVIOUS FORECAST TOWARDS THE ECMWF AND SHALLOW BAM...UNDER THE
 ASSUMPTION THAT PHILIPPE WILL NOT BE ABLE TO MAINTAIN MUCH VERTICAL
 COHERENCE OVER THE NEXT TWO TO THREE DAYS.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  01/0300Z 24.0N  46.4W   45 KT  50 MPH
  12H  01/1200Z 24.7N  47.5W   45 KT  50 MPH
  24H  02/0000Z 25.5N  49.4W   40 KT  45 MPH
  36H  02/1200Z 26.1N  51.5W   40 KT  45 MPH
  48H  03/0000Z 26.5N  53.4W   35 KT  40 MPH
  72H  04/0000Z 27.0N  57.5W   30 KT  35 MPH
  96H  05/0000Z 28.0N  60.0W   30 KT  35 MPH
 120H  06/0000Z 31.0N  60.0W   35 KT  40 MPH
  
 $$
 FORECASTER FRANKLIN