Short summary is Nora should not impact us very much, but stay tuned as the track can always change.
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
