685 
 WTPA43 PHFO 032056
 TCDCP3
 
 TROPICAL STORM IGNACIO DISCUSSION NUMBER  40
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP122015
 1100 AM HST THU SEP 03 2015
  
 THE INNER CORE STRUCTURE OF IGNACIO IS STARTING TO DETERIORATE ONCE
 AGAIN...AS SHOWN BY AN SSMI PASS AT 1408 UTC AND AN SSMI/S AT 1456
 UTC. SINCE THEN...THE SHORT-LIVED INTERMITTENT EYE FEATURE HAS
 FILLED ONCE AGAIN. THE CURRENT INTENSITY ESTIMATES WERE 3.0 FROM
 UW-CIMSS ADT...3.5 FROM SAB AND JTWC...AND 4.0 AT PHFO. HAVE
 LOWERED IGNACIO BACK TO 60 KT FOR THIS ADVISORY BASED ON A CONSENSUS
 OF THESE ESTIMATES.
 
 THE INITIAL MOTION ESTIMATE IS 320/11...BUT THERE IS SOME
 UNCERTAINTY AS TO WHETHER OR NOT THIS IS THE BEGINNING OF THE
 ANTICIPATED NORTHWARD TURN...OR A TEMPORARY WOBBLE. THERE IS NO
 SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY OF THE PAST FEW
 DAYS...AND THE TRACK AND INTENSITY GUIDANCE IS IN GOOD AGREEMENT FOR
 MOST OF THE FORECAST. OVER THE NEXT DAY OR SO...A SHORTWAVE TROUGH
 TO THE NORTHWEST OF THE CYCLONE WILL PICK UP THE SYSTEM AND DRIVE IT
 NORTHWARD TOWARD HIGHER LATITUDES. AS IT GAINS LATITUDE...IT WILL
 ENCOUNTER STRONGER WESTERLIES WHICH WILL PROPEL IT EASTWARD ACROSS
 THE CHILLY WATERS OF THE NORTH PACIFIC. SHEAR IS EXPECTED TO REMAIN
 MODERATE FOR THE NEXT DAY OR SO...AND THE SEA SURFACE TEMPERATURES
 ONLY GRADUALLY DECREASE...SO IGNACIO IS EXPECTED TO MAINTAIN
 INTENSITY OR ONLY VERY SLOWLY SPIN DOWN IN THE FIRST 48 HOURS.
 AFTERWARD...BAROCLINIC INFLUENCES MAY HELP TO SUSTAIN THE SYSTEM AS
 EXTRATROPICAL TRANSITION IS EXPECTED WITH IGNACIO MOVING OVER
 SUB-20C SEA SURFACE TEMPERATURES. AT DAYS 4 AND 5 THE FORECAST
 TRACK IS TO THE RIGHT OF THE CONSENSUS GUIDANCE AND MORE IN LINE
 WITH THE ECMWF GUIDANCE. 
 
 FORECAST TRACK...INTENSITY...AND RADII FOR DAYS 3 THROUGH 5 WERE
 COORDINATED WITH THE OCEAN PREDICTION CENTER IN WASHINGTON D.C.
 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  03/2100Z 29.4N 162.5W   60 KT  70 MPH
  12H  04/0600Z 30.7N 163.7W   60 KT  70 MPH
  24H  04/1800Z 33.2N 164.4W   60 KT  70 MPH
  36H  05/0600Z 36.1N 164.8W   60 KT  70 MPH
  48H  05/1800Z 39.1N 164.9W   55 KT  65 MPH
  72H  06/1800Z 44.6N 163.5W   50 KT  60 MPH...BECOMING EXTRATROPICAL
  96H  07/1800Z 49.2N 152.5W   45 KT  50 MPH...POST-TROP/EXTRATROP
 120H  08/1800Z 52.5N 137.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
  
 $$
 FORECASTER R BALLARD