951 
 WTPA45 PHFO 201457
 TCDCP5
 
 TROPICAL DEPRESSION FIVE-C DISCUSSION NUMBER   7
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP052015
 500 AM HST SUN SEP 20 2015
  
 THE SATELLITE PRESENTATION OF FIVE-C HAS CHANGED LITTLE DURING
 THE NIGHT. 11-3.9 MICRON FOG PRODUCT IMAGERY CONTINUES TO DEPICT
 A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER /LLCC/ DISPLACED
 TO THE SOUTH AND WEST OF THE DEEP CONVECTION. STRONG
 WEST-SOUTHWESTERLY VERTICAL WIND SHEAR CONTINUES TO IMPACT THE
 SYSTEM...WITH GOES UPPER-LEVEL SATELLITE WIND RETRIEVALS AND THE
 LATEST SHIPS/UW-CIMSS SHEAR ESTIMATES ALL INDICATING SHEAR
 MAGNITUDES OF 25 TO 30 KT. SUBJECTIVE DVORAK CURRENT INTENSITY
 ESTIMATES CAME IN AT 2.0/30 KT FROM JTWC...AND 1.5/25 KT FROM
 PHFO/SAB...WHILE THE LATEST UW-CIMSS ADT INTENSITY ESTIMATE IS ALSO
 1.5/25 KT. CONSIDERING THAT THE SATURDAY MORNING ASCAT PASS FOUND
 SIGNIFICANT AREAS OF 30 KT WINDS IN THE EASTERN SEMICIRCLE...AND THE
 OVERNIGHT ASCAT PASS DID NOT SAMPLE THAT AREA OF THE SYSTEM...THE
 INITIAL INTENSITY WILL BE CONSERVATIVELY HELD AT 30 KT FOR THIS
 ADVISORY.
  
 TRACKING OF THE LLCC VIA FOG PRODUCT IMAGERY YIELDS AN INITIAL
 MOTION ESTIMATE OF 015/08 KT. THE DEPRESSION CONTINUES TO MOVE
 TOWARD THE NORTH-NORTHEAST BETWEEN A BROAD AND DEEP TROUGH CENTERED
 WEST OF THE INTERNATIONAL DATE LINE AND A LOW TO MID LEVEL RIDGE
 LOCATED FAR TO THE NORTHEAST. THE CYCLONE IS EXPECTED TO CONTINUE ON
 THIS SAME GENERAL TRACK WITH SOME INCREASE IN FORWARD SPEED TODAY
 AND TONIGHT...AS STEERING FLOW AROUND THE DEEP TROUGH STRENGTHENS. 
 A TURN TOWARD THE NORTH AND THEN THE NORTH-NORTHWEST IS EXPECTED
 FOR MONDAY AND BEYOND...AS THE SYSTEM BECOMES DRAWN INTO THE DEEP 
 TROUGH. MOST OF THE RELIABLE DYNAMICAL GUIDANCE REMAIN REASONABLY 
 WELL CLUSTERED ABOUT THE FORECAST TRACK DIRECTION THROUGH THE NEXT 
 48 HOURS...ALTHOUGH AS WITH PREVIOUS FORECAST CYCLES THERE ARE STILL 
 SIGNIFICANT DIFFERENCES IN THE SPEED OF MOTION ALONG THIS TRACK. AS 
 NOTED PREVIOUSLY...THE 00Z ECMWF DEPICTS A MORE WESTERLY AND SLOWER 
 TRACK THAN DOES MOST OF THE OTHER GUIDANCE. THE NEW OFFICIAL TRACK 
 IS VERY SIMILAR TO THE PREVIOUS TRACK AND CLOSE TO THE TVCN 
 CONSENSUS THROUGH 48 HOURS...THEN IS ADJUSTED MODESTLY AT 72 AND 96 
 HOURS TO INCORPORATE INPUT FROM THE OCEAN PREDICTION CENTER.
  
 THE INTENSITY FORECAST REMAINS PROBLEMATIC. SHIPS AND GLOBAL
 MODEL GUIDANCE INDICATE THAT THE CURRENT SHEAR WILL REMAIN NEAR
 THE CURRENT LEVELS FOR ANOTHER 24 HOURS...THEN INCREASE FURTHER
 AS THE CYCLONE MOVES CLOSER TO THE DEEP MID-LATITUDE TROUGH.
 DESPITE THIS...THE LATEST SHIPS STILL SHOWS SOME SLIGHT
 INTENSIFICATION BY 24 HOURS...BRINGING THE SYSTEM TO MINIMAL
 TROPICAL STORM STRENGTH. THE GFS ALSO DEPICTS SOME MODEST
 INTENSIFICATION DURING THE NEXT COUPLE OF DAYS. THE NEW
 INTENSITY FORECAST FOLLOWS THE PREVIOUS ONE...BRINGING THE CYCLONE
 TO 35 KT AT 24 HOURS AND THEN HOLDING INTENSITY STEADY THEREAFTER
 THROUGH 48 HOURS. THIS IS GENERALLY SIMILAR TO THE SHIPS AND
 HWRF...BUT WELL BELOW THE GFDL. THE SYSTEM IS EXPECTED TO BEGIN
 EXTRATROPICAL TRANSITION BY 48 HOURS...AND SHOULD HAVE COMPLETED
 THIS TRANSITION BEFORE 72 HOURS. THE 72 AND 96 HOUR INTENSITY AND
 72 HOUR WIND RADII FORECASTS WERE ALSO COORDINATED WITH THE OCEAN
 PREDICTION CENTER.
  
 THERE ARE NO CHANGES TO THE EXISTING TROPICAL STORM WATCHES AND
 WARNINGS POSTED FOR PORTIONS OF THE PAPAHANAUMOKUAKEA MARINE
 NATIONAL MONUMENT. IF CURRENT TRENDS CONTINUE...WE MAY BE ABLE
 TO DISCONTINUE THE TROPICAL STORM WATCH FROM LISIANSKI TO PEARL AND
 HERMES LATER TODAY. 
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  20/1500Z 21.1N 173.7W   30 KT  35 MPH
  12H  21/0000Z 22.7N 173.2W   30 KT  35 MPH
  24H  21/1200Z 25.5N 172.3W   35 KT  40 MPH
  36H  22/0000Z 27.9N 172.1W   35 KT  40 MPH
  48H  22/1200Z 30.4N 172.4W   35 KT  40 MPH...BECOMING EXTRATROPICAL
  72H  23/1200Z 35.0N 174.5W   40 KT  45 MPH...POST-TROP/EXTRATROP
  96H  24/1200Z 41.0N 179.0W   35 KT  40 MPH...POST-TROP/EXTRATROP
 120H  25/1200Z...DISSIPATED
  
 $$
 FORECASTER JACOBSON