WDPN31 PGTW 251500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 19W (SAUDEL) WARNING NR 
027//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS. 
   TROPICAL STORM (TS) 19W (SAUDEL), LOCATED APPROXIMATELY 93 NM 
NORTH-NORTHWEST OF DA NANG, VIETNAM, HAS TRACKED WESTWARD AT 03 
KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED 
SATELLITE IMAGERY REVEALS A FULLY-EXPOSED LOW-LEVEL CIRCULATION 
CENTER (LLCC) WITH ALL CONVECTION SHEARED TO THE WEST. OVER THE PAST 
SIX HOURS, THE SYSTEM HAS SLOWED IN ITS WESTWARD TRANSIT. A 251121Z 
SSMIS 91 GHZ COMPOSITE MICROWAVE IMAGE DEPICTS CONVECTIVE BANDING TO 
THE NORTH OF THE SYSTEM WRAPPING INTO THE LLCC, LENDING GOOD 
CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY IS SET AT 
35 KTS WITH GOOD CONFIDENCE BASED ON A DVORAK CURRENT INTENSITY 
ESTIMATE OF T2.5 (35 KTS) BY RJTD AND A 251140Z ADVANCED DVORAK 
TECHNIQUE ESTIMATE OF T2.2 (32 KTS). ENVIRONMENTAL ANALYSIS SHOWS 
MODERATE TO HIGH (20-30 KTS) VERTICAL WIND SHEAR (VWS), FAIR 
WESTWARD OUTFLOW, AND MARGINAL (26-27 CELSIUS) SEA SURFACE 
TEMPERATURES (SST). TS 19W IS TRACKING WESTWARDS ALONG THE SOUTHERN 
PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE NORTH. 
3. FORECAST REASONING.
   A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE 
PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TS 19W WILL CONTINUE TO TRACK WESTWARD THEN WEST-SOUTHWESTWARD 
THROUGH THE FORECAST PERIOD, STEADILY WEAKENING AS TS 19W APPROACHES 
THE COAST OF VIETNAM. AFTER LANDFALL PRIOR TO TAU 12, THE SYSTEM 
WILL CONTINUE TO WEAKEN AS IT MOVES INLAND, TRACKING ACROSS 
MOUNTAINOUS TERRAIN. SYSTEM DISSIPATION IS EXPECTED BY TAU 24. 
NUMERICAL MODEL GUIDANCE REMAINS IN GOOD AGREEMENT THROUGH TAU 12. 
AS THE SYSTEM MOVES INLAND, MODEL GUIDANCE BEGINS TO DIVERGE. 
DESPITE THIS, THERE IS OVERALL GOOD CONFIDENCE IN THE JTWC FORECAST 
TRACK WHICH LIES NEAR THE MULTI-MODEL CONSENSUS.//
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