451 
 WTPA44 PHFO 112040
 TCDCP4
 
 TROPICAL STORM NORA DISCUSSION NUMBER  10
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP182015
 1100 AM HST SUN OCT 11 2015
  
 SATELLITE PRESENTATION CONSISTS OF AN IRREGULAR 140 TO 150 NM
 DIAMETER CENTRAL DENSE OVERCAST AREA WITH A PROMINENT RAIN BAND
 ALONG THE NORTHERN FLANK EXTENDING EASTWARD. A SINGLE OUTFLOW
 CHANNEL EXTENDS TO THE NORTH NORTHWEST. A 1642 UTC SSMIS MICROWAVE
 PASS SHOWED EYEWALL DEVELOPMENT ALONG THE WESTERN HALF OF THE LOW
 LEVEL CIRCULATION CENTER...LLCC...WHICH WAS EASIER TO SEE AT 85 GHZ 
 THAN 37 GHZ. OVERALL ORGANIZATION APPEARS TO HAVE IMPROVED A BIT 
 SINCE LAST NIGHT. SUBJECTIVE DVORAK SATELLITE INTENSITY ESTIMATES 
 RANGED FROM 3.5...55 KT...FROM PHFO AND JTWC...TO 4.0...65 KT...FROM 
 SAB. UW-CIMSS ADT WAS 3.9...63 KT. WE WILL TAKE A BLEND OF THESE 
 ESTIMATES AND ASSIGN AN INITIAL INTENSITY OF 60 KT FOR THIS 
 ADVISORY...REPRESENTING SOME STRENGTHENING SINCE EARLIER THIS 
 MORNING.
 
 NORA APPEARS TO BE TAKING A RATHER WOBBLY TRACK GENERALLY TOWARD
 THE WEST NORTHWEST. LONG TERM MOTION...OVER THE PAST 12 TO 24
 HOURS...IS ABOUT 290/12 KT. HOWEVER...SHORT TERM MOTION IS MORE
 LIKE 305/12 KT. SINCE THE 1800 UTC ANALYSIS CYCLE...NORA APPEARS TO
 HAVE RESUMED A MORE WESTERLY MOTION ONCE AGAIN. UNFORTUNATELY...THE
 ASSIGNED INITIAL MOTION OF 295/12 KT...A COMPROMISE OF SHORT AND
 LONG TERM MOTION...IMMEDIATELY TAKES THIS SYSTEM TO THE RIGHT OF
 THE PREVIOUS TRACK AND JUST OUTSIDE THE RELIABLE TRACK GUIDANCE
 ENVELOPE THROUGH 36 HOURS. THE FINAL FORECAST TRACK FALLS BACK
 WITHIN THIS ENVELOPE BY 48 HOURS...THEN FOLLOWS THE TVCN CONSENSUS
 TRACK THROUGH EXPECTED RECURVATURE. THIS REPRESENTS A FORECAST
 TRACK ADJUSTMENT TO THE RIGHT OF THE PREVIOUS ONE AT ALL TAU. THE
 MAIN TRACK FORECAST CHALLENGE REMAINS THE TIMING OF RECURVATURE AS
 DEEP TROUGHING NORTH OF THE MAIN HAWAIIAN ISLANDS MOVES EASTWARD AND
 WEAKENS THE RIDGE NORTH OF NORA...THEN SCOOPS NORA NORTHEASTWARD OUT
 OF THE DEEP TROPICS. THIS TIMING VARIES FROM MODEL TO MODEL...AND
 FROM RUN TO RUN...SO EXPECT FUTURE TRACK CHANGES AS GUIDANCE
 GRAPPLES WITH THE EFFECTS OF THE TROUGH. IN SPITE OF THIS
 UNCERTAINTY...ALL OF THE GUIDANCE EITHER RECURVES NORA NORTHEASTWARD
 FAR FROM HAWAII...OR DECAPITATES NORA AND SHOVES THE REMNANTS WEST
 SOUTHWESTWARD WITHIN THE TRADES. 
 
 THERE IS A SMALL WINDOW FOR ADDITIONAL DEVELOPMENT AS SHEAR REMAINS 
 RELATIVELY LOW AND SEA SURFACE TEMPERATURES ACROSS THE FORECAST 
 TRACK REMAIN NEAR 29C. WE FORECAST NORA WILL REACH HURRICANE 
 STRENGTH IN 12 HOURS...MAINTAIN THIS STRENGTH THROUGH 24 
 HOURS...THEN GRADUALLY WEAKEN AS SHEAR BEGINS TO INCREASE WITH THE 
 APPROACH OF THE DEEP TROUGH. THIS IS IN LINE WITH SHIPS GUIDANCE 
 THROUGH 72 HOURS. HOWEVER...WE KEEP NORA AT MINIMAL TROPICAL STORM 
 STRENGTH THROUGH 120 HOURS WHILE SHIPS DISSIPATES IT. THE FORECAST 
 WEAKENING TREND FOLLOWS...BUT IS JUST BELOW...THE TRENDS DEPICTED IN 
 GFS AND ECMWF.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  11/2100Z 12.9N 143.2W   60 KT  70 MPH
  12H  12/0600Z 13.4N 144.5W   65 KT  75 MPH
  24H  12/1800Z 13.9N 146.0W   65 KT  75 MPH
  36H  13/0600Z 14.5N 147.0W   60 KT  70 MPH
  48H  13/1800Z 15.4N 147.6W   55 KT  65 MPH
  72H  14/1800Z 16.6N 147.6W   50 KT  60 MPH
  96H  15/1800Z 17.9N 147.0W   45 KT  50 MPH
 120H  16/1800Z 19.4N 146.2W   35 KT  40 MPH
  
 $$
 FORECASTER POWELL