Tropical Storm LINGLING Advisory Sat Sep 07

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 15W (LINGLING) WARNING NR 018//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 15W (LINGLING), LOCATED APPROXIMATELY 384 NM SOUTH
OF KUNSAN AB, HAS TRACKED NORTHWARD AT 15 KNOTS (KTS) OVER THE PAST
SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS TY 15W
WITH A WELL-DEFINED 8-NM EYE FEATURE LENDING HIGH CONFIDENCE TO THE
PLACEMENT OF THE INITIAL POSITION. A 060507Z AMSR2 89 GHZ MICROWAVE
IMAGE DEPICTS A TIGHT CIRCULATION WITH SHARPLY OUTLINED RAIN BANDS
WRAPPING INTO THE EYE AND A VERY DEEP EYEWALL OVER 50 PERCENT OF THE
STORM. THE INITIAL INTENSITY OF 110 KTS IS BASED ON AN ASSESSMENT OF
DVORAK FINAL T AND CURRENT INTENSITY ESTIMATES RANGING FROM T5.0-6.0
(90-115 KTS) THAT INDICATES SUBTLE WEAKENING OF THE SYSTEM FROM THE
PRIOR FORECAST. UPPER LEVEL ANALYSIS INDICATES THAT THE SYSTEM IS
PASSING THROUGH AN AREA OF MODERATE (15-20 KTS) VERTICAL WIND SHEAR
(VWS); HOWEVER, THERE CONTINUES TO BE EXCELLENT POLEWARD AND
EQUATORWARD OUTFLOW. ADDITIONALLY, ALONG-TRACK SEA SURFACE
TEMPERATURE (SST) REMAINS FAVORABLE AT 28-30 CELSIUS. TY 15W IS
TRACKING NORTHWARD, TRANSITING ALONG THE WESTERN PERIPHERY OF A
SUBTROPICAL RIDGE (STR) TO THE EAST.
3. FORECAST REASONING.
   A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. PRIOR TO TAU 24, TY 15W WILL MAINTAIN THE CURRENT NORTHWARD
TRACK ALONG THE PERIPHERY OF THE STR. AFTER TAU 24, THE TRACK WILL
SHIFT NORTH-NORTHEASTWARD WHILE MAKING LANDFALL ALONG THE SOUTH
COAST OF NORTH KOREA. INCREASING VWS AND COOLING SST VALUES WILL
GRADUALLY WEAKEN TY 15W AS IT APPROACHES THE COAST. AFTER MAKING
LANDFALL, THE RUGGED TERRAIN WILL CAUSE MORE RAPID WEAKENING. AROUND
TAU 24, TY 15W WILL BEGIN EXTRA-TROPICAL TRANSITION (ETT) AS IT
BEGINS INTERACTING WITH THE MIDLATITUDE BAROCLINIC ZONE. THE TAU 36
POSITION SHOWS AN INCREASING TRACK SPEED AND WIND RADII AS THE
SYSTEM COMPLETES ETT AND TRANSFORMS INTO A COLD CORE LOW. NUMERICAL
MODELS ARE IN TIGHT AGREEMENT THROUGHOUT THE FORECAST, THUS THERE IS
HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.//
NNNN
NNNN