WDPN31 PGTW 250300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 22W (TWENTYTWO) 
WARNING NR 06//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL DEPRESSION 22W (TWENTYTWO), LOCATED APPROXIMATELY 138 NM 
EAST-SOUTHEAST OF HANOI, VIETNAM, HAS TRACKED WEST-NORTHWESTWARD AT 
15 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE 
IMAGERY DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER 
(LLCC) WITH FLARING CENTRAL CONVECTION BEING SHEARED TO THE 
SOUTHWEST. THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON 
THE EXPOSED LLCC. THE INITIAL INTENSITY IS ASSESSED AT 30 KNOTS AND 
IS BASED ON RECENT SHIP OBSERVATIONS AND MULTI-AGENCY DVORAK 
ESTIMATES RANGING FROM T1.5 TO T2.0 (25 TO 30 KNOTS). ENVIRONMENTAL 
CONDITION ARE CURRENTLY MARGINAL AS EASTERLY UPPER-LEVEL FLOW FROM 
THE SUBTROPICAL RIDGE TO THE NORTH IS EXERTING STRONG VERTICAL WIND 
SHEAR. UPPER-LEVEL DIVERGENCE TO THE SOUTHWEST IS FAIRLY ROBUST AND 
FUELING THE FLARING CONVECTION. CURRENTLY TD 22W IS TRACKING WEST-
NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED 
SUBTROPICAL RIDGE TO THE NORTH ANCHORED OVER TAIWAN AND THE EASTERN 
SHORE OF CHINA.       
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS 
PROGNOSTIC REASONING MESSAGE.  
   B. TD 22W WILL CONTINUE TO TRACK NORTHWESTWARD ALONG THE SOUTHERN 
BOUNDARY OF THE SUBTROPICAL RIDGE FOR THE REMAINDER OF THE FORECAST 
PERIOD. THE SYSTEM IS FORECAST TO MAINTAIN ITS CURRENT INTENSITY 
UNDER THE MARGINAL CONDITIONS BEFORE MAKING LANDFALL OVER THE 
NORTHERN PORTION OF VIETNAM AND BEGIN DISSIPATING AS IT TRACKS 
FURTHER INLAND. TD 22W IS FORECAST TO FULLY DISSIPATE BY TAU 24. 
DYNAMIC MODEL GUIDANCE SHOWS FAIRLY GOOD AGREEMENT OVER THE NEXT 12 
HOURS BUT BEGINS TO DIVERGE THEREAFTER AS IT DISSIPATES OVER LAND. 
OVERALL THERE IS HIGH CONFIDENCE IN THE FORECAST TRACK.//
NNNN