MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 14W (FOURTEEN) WARNING NR 03// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION (TD) 14W (FOURTEEN), LOCATED APPROXIMATELY 358 NM SOUTH-SOUTHEAST OF YOKOSUKA, JAPAN, HAS TRACKED WEST- NORTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A MOSTLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH PULSING CONVECTION SHEARED TO THE EAST DUE TO PERSISTENT 20 KNOT WESTERLY VERTICAL WIND SHEAR (VWS). A 021737Z SSMI 85GHZ MICROWAVE IMAGE SHOWS A COMPACT, MIDGET SIZED LLCC WITH VERY LIMITED CONVECTION TO THE EAST. THE MICROWAVE IMAGE REVEALS THAT DRY AIR IS ALMOST COMPLETELY SURROUNDING THE LLCC. THE CURRENT POSITION IS BASED ON THE PARTIALLY EXPOSED LLCC IN THE ABOVE IMAGERY WITH GOOD CONFIDENCE. THE CURRENT INTENSITY IS HELD AT 30 KNOTS BASED ON NO CHANGE IN OVERALL STRUCTURE AND A WELL DEFINED LLCC IN MICROWAVE IMAGERY. UPPER LEVEL ANALYSIS INDICATES A MARGINAL ENVIRONMENT DUE TO THE AFOREMENTIONED DRY AIR AND MODERATE VWS. WATER VAPOR IMAGERY SHOWS REDUCED OUTFLOW TO THE WEST AS THE TUTT CELL IS WEAKENING; HOWEVER, AN APPROACHING UPPER LEVEL TROUGH CURRENTLY SITUATED OVER JAPAN IS CREATING A POLEWARD OUTFLOW CHANNEL. TD 14W IS EMBEDDED ALONG THE SOUTHERN PERIPHERY OF THE LOW- LEVEL SUB-TROPICAL RIDGE (STR), WHICH EXTENDS OVER THE NORTHERN AND WESTERN PERIPHERIES OF THE SYSTEM. THIS IS LEADING TO A SLOW WESTWARD TRACK. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TD 14W IS FORECAST TO TRACK SLOWLY WESTWARD THROUGHOUT THE FORECAST PERIOD UNDER THE STEERING INFLUENCE OF THE LOW-LEVEL STR. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO DEGRADE AS THE APPROACHING TROUGH ENGULFS THE SYSTEM, INCREASING THE VWS AND DRY AIR. TD 14W IS FORECAST TO WEAKEN AND DISSIPATE OVER WATER BY THE END OF THE FORECAST PERIOD. DYNAMIC GUIDANCE IS IN FAIR AGREEMENT WITH A GENERAL WESTWARD TRACK AND SUPPORTS THE JTWC FORECAST TRACK WITH HIGH CONFIDENCE.// NNNN NNNN