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 750 
 WTPA44 PHFO 030916
 TCDCP4
 
 HURRICANE GUILLERMO DISCUSSION NUMBER  18
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP092015
 1100 PM HST SUN AUG 02 2015
  
 LATEST SATELLITE IMAGERY CONTINUES TO SHOW DEEP CONVECTION 
 STRUGGLING TO MAINTAIN ITSELF OVER THE LOW LEVEL CIRCULATION CENTER 
 GUILLERMO DUE TO THE INCREASING WESTERLY WIND SHEAR THE SYSTEM IS 
 ENCOUNTERING. THE U.S. 53RD WEATHER RECONNAISSANCE AIRCRAFT 
 CONFIRMED THAT THE SYSTEM IS WEAKENING WHILE SAMPLING THE INNER CORE 
 OF GUILLERMO THIS EVENING...WITH NO FLIGHT LEVEL OR SURFACE WINDS OF 
 64 KNOTS OR GREATER FOUND. THE CENTRAL PRESSURE OF THE SYSTEM HAD 
 RISEN TO AROUND 990 MB AS WELL. ADDITIONALLY...DVORAK 
 CLASSIFICATIONS WERE 4.5/77KT FROM PHFO AND JTWC AND 4.0/65 KT FROM 
 SAB...WHILE FINAL T NUMBERS WERE LOWER AT 3.5 TO 4.0. FOR THE 
 INITIAL 0600Z INTENSITY WE USED 70 KNOTS WHICH FOLLOWED CLOSELY THE 
 DVORAK NUMBERS...BUT AS A RESULT OF THE AIRCRAFT SAMPLING OF 
 GUILLERMO THE 0900Z INITIAL INTENSITY WILL BE ADJUSTED DOWNWARD TO 
 65 KNOTS. 
 
 THE INITIAL MOTION IS TOWARD THE WEST-NORTHWEST...OR 300 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 TIGHT CLUSTERING OF THE MODELS THEN SHOWS
 INCREASING SPREAD BETWEEN 48 HOURS AND 120 HOURS...LIKELY DUE TO
 THE DIFFERING INTENSITY FORECASTS BY THE VARIOUS MODELS WITH
 RESPECT TO THE SYSTEM. 
  
 THE LATEST UW-CIMSS VERTICAL WIND SHEAR ANALYSIS SHOWED 8 KNOTS
 FROM 290 DEGREES...WHILE THE LATEST SHIPS ANALYSIS SHOWED 16 KNOTS
 FROM 285 DEGREES. THIS IS LIKELY RESPONSIBLE FOR THE POOR
 SATELLITE PRESENTATION AND THE WEAKENING OF THE SYSTEM SINCE THE
 PREVIOUS ADVISORY. 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 FURTHER DISRUPTED AND VERTICAL WIND SHEAR WILL
 CONTINUE TO SLOWLY INCREASE. THE INTENSITY FORECAST CLOSELY FOLLOWS
 THE ICON...WITH SHIPS PREDICTING MORE RAPID WEAKENING BEYOND 48
 HOURS. THE FORECAST AND INITIAL WIND RADII WERE ADJUSTED BASED ON
 THE AIRCRAFT DATA AS WELL. 
  
 AS GUILLERMO MOVES CLOSER TO HAWAII...WATCHES MAY BE ISSUED MONDAY
 OR MONDAY NIGHT 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.
  
 ANOTHER RECONNAISSANCE AIRCRAFT MISSION INTO GUILLERMO IS
 SCHEDULED FOR MONDAY MORNING. THE VALUABLE DATA TRANSMITTED IN
 REAL-TIME FROM THESE MISSIONS WILL HELP US TO BETTER DETERMINE THE
 LOCATION...INTENSITY AND SIZE OF THE HURRICANE. IN ADDITION...THE
 NOAA G-IV JET IS SCHEDULED TO CONDUCT ANOTHER SYNOPTIC SAMPLING
 MISSION AROUND GUILLERMO MONDAY AFTERNOON. THIS SAMPLING SHOULD HELP
 IMPROVE THE MODEL INITIALIZATION OF GUILLERMO.
 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  03/0900Z 16.2N 145.4W   65 KT  75 MPH
  12H  03/1800Z 16.8N 146.5W   60 KT  70 MPH
  24H  04/0600Z 17.5N 148.1W   55 KT  65 MPH
  36H  04/1800Z 18.1N 149.8W   50 KT  60 MPH
  48H  05/0600Z 18.9N 151.5W   45 KT  50 MPH
  72H  06/0600Z 20.5N 155.0W   40 KT  45 MPH
  96H  07/0600Z 22.6N 158.9W   35 KT  40 MPH
 120H  08/0600Z 24.5N 163.1W   30 KT  35 MPH
  
 $$
 FORECASTER JELSEMA/HOUSTON
  
 
 
 
 
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