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 WTPA44 PHFO 042052
 TCDCP4
 
 HURRICANE JIMENA DISCUSSION NUMBER  37
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP132015
 1100 AM HST FRI SEP 04 2015
  
 THE SATELLITE PRESENTATION OF JIMENA HAS DEGRADED SLIGHTLY DURING 
 THE PAST SIX HOURS. WESTERLY VERTICAL WIND SHEAR IS UP TO 19 KT 
 ACCORDING TO THE 1800 UTC CIMSS ANALYSIS...CAUSING OUTFLOW TO
 BECOME DISRUPTED IN THE WEST AND SOUTHWEST QUADRANTS. THE AREA OF
 DEEP CONVECTION NEAR THE CENTER DECREASED SLIGHTLY IN SIZE WITH
 CLOUD TOPS SHOWING SOME WARMING. DVORAK CURRENT INTENSITY ESTIMATES
 FROM HFO AND SAB CAME IN AT 4.0/65 KT...WHILE JTWC HAD 4.5/77 KT.
 CIMSS ADT SUPPORTED 65 KT...AND CIMSS SATCON FROM 1630 UTC WAS AT 67
 KT. BASED ON A BLEND OF THESE ESTIMATES AND A CONTINUATION OF THE 
 WEAKENING TREND...THE INITIAL INTENSITY HAS BEEN LOWERED TO 70 KT 
 FOR THIS ADVISORY.
 
 JIMENA REMAINS WITHIN A WEAK STEERING ENVIRONMENT WITH A SLOW 
 FORWARD MOTION. ALTHOUGH THE LOW LEVEL CENTER WAS DIFFICULT TO 
 LOCATE WITH GEOSTATIONARY IMAGERY...A WINDSAT PASS AT 1618 UTC AND 
 SSMIS PASSES AT 1629 AND 1643 UTC CONFIRMED THAT JIMENA WAS MOVING 
 CLOSE TO THE PRIOR FORECAST TRACK...AND THE INITIAL MOTION IS SET 
 TOWARD THE NORTHWEST...OR 320 DEGREES...AT 4 KT. JIMENA WILL 
 CONTINUE ON A SIMILAR TRACK WITH A RATHER SLOW FORWARD MOTION OVER 
 THE NEXT THREE DAYS. THIS MOTION WILL BE INDUCED BY A MID TO UPPER 
 LEVEL TROUGH PARKED JUST WEST OF HAWAII THAT WILL PRODUCE A
 WEAKNESS IN THE LOW LEVEL RIDGE CENTERED OVER 1000 MILES NORTH OF
 THE CYCLONE. THE GUIDANCE IS TIGHTLY CLUSTERED DURING THIS TIME BUT 
 DIVERGES SIGNIFICANTLY ON DAYS FOUR AND FIVE. THE OFFICIAL FORECAST 
 HAS BEEN NUDGED SLIGHTLY SOUTHWARD WITH AN INCREASE IN FORWARD
 SPEED ON DAYS FOUR AND FIVE IN ANTICIPATION OF A BUILDING UPPER
 LEVEL RIDGE PRODUCING NORTHWESTERLY FLOW ALOFT AND A WEAKER JIMENA 
 BECOMING INCREASINGLY STEERED BY THE LOW LEVEL RIDGE TO THE NORTH. 
 THE OFFICIAL FORECAST CLOSELY FOLLOWS THE TVCN TRACK...THOUGH IT
 HAS A SLOWER FORWARD MOTION ON DAY FIVE. THE NOTABLE SOUTHERN
 OUTLIER IS THE ECMWF...AND THE OFFICIAL FORECAST FALLS BETWEEN THE
 OPERATIONAL GFS TO THE SOUTH AND THE GFS ENSEMBLE MEAN TO THE NORTH.
 
 GRADUAL WEAKENING IS EXPECTED THROUGH THE NEXT FIVE DAYS. WESTERLY 
 VERTICAL WIND SHEAR IS FORECAST TO HOLD AT 15 TO 20 KT DURING THE 
 NEXT THREE DAYS THEN SHIFT OUT OF THE NORTHWEST ON DAYS FOUR AND 
 FIVE. THIS SHOULD CONTINUE TO DISRUPT THE OUTFLOW AND IS EXPECTED 
 TO LEAD TO CONTINUED SLOW WEAKENING. THE INTENSITY FORECAST CLOSELY 
 FOLLOWS THE PRIOR FORECAST AND IS IN GOOD AGREEMENT WITH ICON.
 THERE ARE NOTABLE DIFFERENCES IN THE GUIDANCE. THE GFS AND THE
 ECMWF MAINTAIN A STRONGER CYCLONE...WHILE THE GFDL AND HWRF SUGGEST
 A RAPID WEAKENING LATE DAY FOUR AND DAY FIVE. MEANWHILE...SHIPS AND 
 LGEM WEAKEN JIMENA AT A MUCH FASTER RATE THAN THE OFFICIAL FORECAST.
  
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  04/2100Z 20.0N 145.3W   70 KT  80 MPH
  12H  05/0600Z 20.5N 145.7W   65 KT  75 MPH
  24H  05/1800Z 21.4N 146.2W   60 KT  70 MPH
  36H  06/0600Z 22.5N 146.8W   60 KT  70 MPH
  48H  06/1800Z 23.6N 147.7W   55 KT  65 MPH
  72H  07/1800Z 24.9N 150.0W   50 KT  60 MPH
  96H  08/1800Z 24.9N 152.0W   45 KT  50 MPH
 120H  09/1800Z 24.7N 155.0W   35 KT  40 MPH
  
 $$
 FORECASTER WROE