Tropical Storm JANGMI Advisory zo, 09-08

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 05W (JANGMI)
WARNING NR 04//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 05W (JANGMI), LOCATED APPROXIMATELY 222 NM SOUTH-
SOUTHWEST OF KADENA AB, HAS TRACKED NORTHWARD AT 18 KNOTS OVER THE
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH
DEEP CONVECTION DISPLACED OVER THE EASTERN SEMICIRCLE. THE INITIAL
POSITION IS PLACED WITH FAIR CONFIDENCE BASED ON THE LOW LEVEL
FEATURES PRESENT IN THE MSI LOOP AND THE WEAK LOW-LEVEL BANDING FROM
A 082245Z F17 SSMIS 91GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY OF
30 KTS IS SET WITH GOOD CONFIDENCE IN AGREEMENT WITH A DVORAK CURRENT
INTENSITY ESTIMATES OF T1.5-2.5 (25-35 KTS) FROM PGTW AND RJTD. THE
INTENSITY IS FURTHER SUPPORTED BY AN ADVANCED DVORAK TECHNIQUE
ESTIMATE OF 33 KNOTS AT 090000Z. TD 05W IS TRACKING ALONG THE
PERIPHERY OF A SUBTROPICAL RIDGE (STR) POSITIONED TO THE EAST AND
THROUGH AN OVERALL FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW
(10-15 KNOTS) VERTICAL WIND SHEAR AND WARM (30-31 CELSIUS) SEA
SURFACE TEMPERATURES (SST). THE SYSTEM CURRENTLY REMAINS UNDER FAIR
UPPER LEVEL SUPPORT, HOWEVER CONVERGENT FLOW ALOFT ALONG THE
NORTHWEST PERIPHERY OF THE SYSTEM IS OFFSETTING THE OVERALL FAVORABLE
ENVIRONMENT.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
   B. TD 05W IS FORECAST TO CONTINUE TRACKING NORTHWARD ALONG THE
WESTERN PERIPHERY OF THE STR THROUGH TAU 12 BEFORE TURNING SLIGHTLY
NORTHEASTWARD AS IT ROUNDS THE STR SOUTH OF KOREA. DURING THIS TIME,
THE SYSTEM IS FORECAST TO REACH A PEAK INTENSITY OF 40 KNOTS AT TAU
24 AS IT TRACKS THROUGH A MODERATELY FAVORABLE ENVIRONMENT WITH WARM
(29-30 DEGREES CELSIUS) SSTS, MODERATE (15-20 KTS) VWS AND CONVERGENT
FLOW FROM THE NORTHWEST. THIS CONVERGENT FLOW IS EXPECTED TO HINDER
INTENSIFICATION BETWEEN TAU 12 TO TAU 24. AT TAU 36, TD 05W IS
EXPECTED TO BEGIN EXTRATROPICAL TRANSITION AS IT MOVES INTO COOLER
WATERS (24-25 DEGREES CELSIUS) AND APPROACHES DEEP WESTERLY FLOW.
AFTER CROSSING THE KOREA STRAIT, TD 05W WILL COMPLETE EXTRATROPICAL
TRANSITION BY TAU 48 AS IT MOVES INTO THE BAROCLINIC ZONE. NUMERICAL
MODEL SOLUTIONS HAVE CONVERGED AND REMAIN IN TIGHT AGREEMENT WITH A
60NM CROSS TRACK SPREAD FOR THE ENTIRE FORECAST PERIOD. THE OVERALL
AGREEMENT OF GLOBAL MODEL SOLUTIONS LEND HIGH CONFIDENCE TO THE JTWC
FORECAST TRACK.//
NNNN
NNNN