WTPA44 PHFO 122050

TCDCP4



TROPICAL STORM NORA DISCUSSION NUMBER  14

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP182015

1100 AM HST MON OCT 12 2015



THE LOW LEVEL CENTER OF NORA BECAME COMPLETELY EXPOSED THIS MORNING

AFTER THE OVERNIGHT BURST OF DEEP CONVECTION FADED AWAY. THE

SUBJECTIVE INTENSITY ESTIMATES ALL CAME IN AT 3.0 WITH AN

OBJECTIVE ESTIMATE OF 3.2 FROM CIMSS. BASED ON THESE VALUES...HAVE

LOWERED THE ADVISORY INTENSITY TO 50 KT...AND THIS IS PROBABLY

GENEROUS. THERE IS STILL A LOOSELY CURVED...BROKEN BAND OF DEEP

CONVECTION TO THE NORTHWEST THROUGH NORTHEAST OF THE CENTER.



NORA IS MOVING TOWARD THE WEST OR 280 DEGREES AT ABOUT 8 KT. IT IS

NEARING THE SOUTHWESTERN PERIPHERY OF THE SUBTROPICAL RIDGE. ONCE

IT DOES SO...A MORE WEST-NORTHWESTWARD MOTION IS EXPECTED TO BEGIN

IN THE NEAR TERM. THIS WILL BE FOLLOWED BY MORE OF A NORTHWARD

MOTION AS A MID-LEVEL TROUGH PASSES NORTH OF HAWAII AND A

BREAK DEVELOPS IN THE SUBTROPICAL RIDGE TO THE NORTHEAST OF THE

MAIN HAWAIIAN ISLANDS. THIS IS VERY LIKELY TO BE FOLLOWED BY AN

ABRUPT CHANGE IN DIRECTION TOWARD THE WEST-SOUTHWEST OR SOUTHWEST

AS STRONG DEEP LAYER SHEAR RENDERS NORA A REMNANT LOW. AS USUAL...

THERE IS SOME UNCERTAINTY AS TO WHEN THE STEERING FLOW BECOMES MORE

SHALLOW...BUT THE DEFINITIVE TREND OF THE GUIDANCE OVER THE LAST

SEVERAL CYCLES IS FOR THIS TO OCCUR SOONER AND THE LATEST FORECAST

REFLECTS THAT AS WELL.



DESPITE BEING OVER WARM SEA SURFACE TEMPERATURES...PERSISTENT

SOUTHWESTERLY SHEAR OF 25-30 KT CONTINUES TO LIMIT CONVECTION NEAR

THE CENTER OF NORA. AS ALLUDED TO ABOVE...THE SHEAR IS EXPECTED TO

PERSIST THROUGH THE REMAINDER OF NORA/S LIFE AS A TROPICAL

CYCLONE...SO CONTINUED GRADUAL WEAKENING IS EXPECTED. THE CURRENT

FORECAST HAS NORA BECOMING A REMNANT LOW IN 96 HOURS...BUT THIS

COULD OCCUR SOONER IF PERSISTENT DEEP CONVECTION CANNOT REESTABLISH

ITSELF.





FORECAST POSITIONS AND MAX WINDS



INIT  12/2100Z 12.8N 146.6W   50 KT  60 MPH

 12H  13/0600Z 13.3N 147.9W   45 KT  50 MPH

 24H  13/1800Z 14.0N 149.3W   40 KT  45 MPH

 36H  14/0600Z 14.7N 150.0W   35 KT  40 MPH

 48H  14/1800Z 15.5N 150.6W   30 KT  35 MPH

 72H  15/1800Z 16.5N 151.0W   25 KT  30 MPH

 96H  16/1800Z 16.2N 152.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

120H  17/1800Z 15.5N 154.0W   25 KT  30 MPH...POST-TROP/REMNT LOW



$$

FORECASTER R BALLARD