506 
 WTPA44 PHFO 030247
 TCDCP4
 
 HURRICANE GUILLERMO DISCUSSION NUMBER  17
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP092015
 500 PM HST SUN AUG 02 2015
  
 THE SATELLITE PRESENTATION OF GUILLERMO CONTINUES TO SLOWLY
 DEGRADE. DEEP CONVECTION IS PULSING AROUND A DIFFICULT TO LOCATE 
 CENTER WITH THE MOST PERSISTENT COLD TOPS CONFINED TO THE NORTHEAST 
 QUADRANT. A 2346 UTC SSMI PASS AND A 0013 UTC AMSU PASS WERE HELPFUL 
 IN DETERMINING A CENTER POSITION. DVORAK CURRENT INTENSITY ESTIMATES 
 WERE 5.0/90 KT FROM SAB AND 4.5/77 KT FROM HFO AND JTWC...WHILE 
 FINAL T NUMBERS WERE LOWER AT 4.0 TO 4.5. CIMSS ADT SUGGESTED 70 
 KT...AND GIVEN RECONNAISSANCE DATA FROM EARLIER IN THE DAY...THE 
 OFFICIAL INTENSITY HAS BEEN LOWERED TO 75 KT.
 
 THE INITIAL MOTION IS TOWARD THE WEST-NORTHWEST...OR 295 DEGREES... 
 AT 9 KT. A LOW LEVEL RIDGE SITS ABOUT 1500 NM TO THE NORTHWEST OF 
 GUILLERMO...WHILE A NORTH PACIFIC UPPER LEVEL TROUGH HAS CARVED OUT 
 A WEAKNESS IN THE MID TO UPPER LEVEL RIDGE JUST NORTH OF THE 
 HURRICANE. GUILLERMO WILL CONTINUE TO MOVE ON A SIMILAR BEARING FOR 
 THE NEXT FEW DAYS INTO THE WEAKNESS ALOFT...TAKING THE SYSTEM NEAR 
 OR POSSIBLY OVER THE HAWAIIAN ISLANDS ON WEDNESDAY AND THURSDAY.
 THE TRACK FORECAST HAS BEEN CHANGED LITTLE FROM THE LAST ADVISORY
 AND REMAINS NEAR A RATHER TIGHT CLUSTER OF GFS...ECMWF...AND THE 
 CONSENSUS MODELS. THE HRWF HAS MOVED BACK SLIGHTLY CLOSER TO THE 
 CONSENSUS...WHILE THE GFDL CONTINUES TO SEND A STRONGER SYSTEM 
 NORTHWARD ON WEDNESDAY.
 
 WEAKENING IS EXPECTED TO CONTINUE THROUGH THE FORECAST PERIOD. AS 
 GUILLERMO CONTINUES TO MOVE INTO THE BREAK IN THE MID TO UPPER
 LEVEL RIDGE...OUTFLOW WITHIN THE NORTHWEST QUADRANT WILL BECOME
 DISRUPTED FURTHER AND VERTICAL WIND SHEAR WILL SLOWLY INCREASE. THE 
 RATE OF WEAKENING HAS BEEN CHANGED LITTLE SINCE THE LAST
 ADVISORY...AND THE FORECAST CLOSELY FOLLOWS THE ICON...WITH SHIPS
 PREDICTING MORE RAPID WEAKENING BEYOND 48 HOURS.
 
 AS GUILLERMO MOVES CLOSER TO HAWAII...WATCHES MAY BE ISSUED AS
 EARLY AS MONDAY MORNING FOR PORTIONS OF THE STATE. HOWEVER...IT IS
 STILL TOO SOON TO DETERMINE WITH CERTAINTY WHICH ISLANDS ARE MOST
 LIKELY TO EXPERIENCE THE GREATEST IMPACTS FROM GUILLERMO. IT IS
 ALSO IMPORTANT TO NOTE THAT SIGNIFICANT IMPACTS CAN EXTEND WELL
 AWAY FROM THE CENTER.
 
 THE NOAA G-IV JET CONDUCTED A SYNOPTIC MISSION NORTH OF GUILLERMO 
 EARLIER THIS AFTERNOON. THIS SAMPLING SHOULD IMPROVE THE MODEL 
 INITIALIZATION OF THE ENVIRONMENT AFFECTING GUILLERMO. THE NEXT
 G-IV MISSION IS SCHEDULED FOR TOMORROW MORNING...AND THE NEXT U.S.
 AIR FORCE MISSION INTO GUILLERMO IS SCHEDULED FOR THIS EVENING.
 
  
  
  
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  03/0300Z 15.5N 145.0W   75 KT  85 MPH
  12H  03/1200Z 16.1N 146.2W   70 KT  80 MPH
  24H  04/0000Z 16.9N 147.7W   65 KT  75 MPH
  36H  04/1200Z 17.5N 149.5W   60 KT  70 MPH
  48H  05/0000Z 18.2N 151.2W   50 KT  60 MPH
  72H  06/0000Z 19.9N 154.8W   45 KT  50 MPH
  96H  07/0000Z 21.9N 158.5W   35 KT  40 MPH
 120H  08/0000Z 24.1N 163.3W   30 KT  35 MPH
  
 $$
 FORECASTER WROE