Tropical Storm NAKRI Advisory 11月8日

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 25W (NAKRI) WARNING NR
009//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL STORM 25W (NAKRI), LOCATED APPROXIMATELY 240 NM WEST-
SOUTHWEST OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD AT
02 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS A CONSOLIDATING SYSTEM WITH A CENTRAL
DENSE OVERCAST FEATURE OBSCURING THE LOW-LEVEL CIRCULATION,
PROVIDING LOW CONFIDENCE IN THE INITIAL POSITION. TS 25W HAS
MAINTAINED AN ERRATIC, QUASI-STATIONARY (QS) TRACK MOTION OVER THE
PAST SIX HOURS. THE CURRENT INTENSITY IS ASSESSED AT 60 KNOTS BASED
ON DVORAK INTENSITY ESTIMATES OF T3.5 (55 KNOTS) FROM PGTW AND RJTD
AND A 071740Z SATCON ESTIMATE OF 61 KNOTS. UPPER-LEVEL ANALYSIS
INDICATES A MARGINALLY-FAVORABLE ENVIRONMENT WITH MODERATE (20-25
KNOTS) EASTERLY VERTICAL WIND SHEAR (VWS) PARTIALLY OFFSET BY UPPER-
LEVEL OUTFLOW TO THE WEST. SST VALUES OF 29-30C ARE CONDUCIVE FOR
FURTHER DEVELOPMENT. TS 25W IS LOCATED WITHIN A COMPETING STEERING
ENVIRONMENT WITH SUBTROPICAL RIDGES LOCATED WEST AND EAST OF THE
SYSTEM AND A BROAD SHORTWAVE TROUGH TO THE NORTH.
3. FORECAST REASONING.
   A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM
THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TS 25W WILL REMAIN QS WITHIN THE COMPETING STEERING
ENVIRONMENT THROUGH TAU 24. AFTER TAU 24, THE SYSTEM SHOULD SLOWLY
TRACK WESTWARD AS THE AFOREMENTIONED SHORTWAVE TROUGH LIFTS POLEWARD
AND A SUBTROPICAL RIDGE (STR) BUILDS NORTH OF THE SYSTEM. TS 25W
WILL GRADUALLY ACCELERATE WESTWARD THROUGH TAU 72 WHILE GRADUALLY
INTENSIFYING TO A PEAK INTENSITY OF 70 KNOTS BY TAU 24.
   C. BEYOND TAU 72, TS NAKRI WILL CONTINUE WESTWARD UNDER THE
AFOREMENTIONED STR EXTENSION, MAKING LANDFALL OVER CENTRAL VIETNAM
AT TAU 72. AFTER LANDFALL, THE SYSTEM WILL WEAKEN RAPIDLY AS IT
TRACKS OVER MOUNTAINOUS TERRAIN WITH DISSIPATION EXPECTED BY TAU
120. DESPITE THE COMPLEX STEERING ENVIRONMENT IN THE EARLY FORECAST
PERIOD, THE NUMERICAL MODELS ARE IN FAIR AGREEMENT; HOWEVER, THE
OVERALL CONFIDENCE IN THE JTWC FORECAST TRACK IS LOW.//
NNNN
NNNN