WDPN31 PGTW 242100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 26W (BUALOI) WARNING NR 
006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 10.7N 130.1E
   INITIAL INTENSITY: 55 KTS
   GEOGRAPHIC REFERENCE: 582 NM EAST-SOUTHEAST OF MANILA,
PHILIPPINES
   MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 09 KTS
   SIGNIFICANT WAVE HEIGHT: 23 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A 
CONSOLIDATING SYSTEM, WITH A SYMMETRIC CENTRAL DENSE OVERCAST (CDO)
OBSCURING THE LOW-LEVEL CIRCULATION CENTER. EIR SATELLITE IMAGERY
INDICATES PRESSURE OVER THE EASTERN EDGE OF THE CDO, WITH A TIGHT
TEMPERATURE GRADIENT ASSOCIATED WITH THE PERSISTENT EASTERLY
VERTICAL WIND SHEAR (VWS), AND INTENSE CONVECTIVE BURSTS (CLOUD TOP
TEMPERATURES AS COLD AS -95C). AS INDICATED IN ANIMATED WATER VAPOR
RGB IMAGERY, THE SYSTEM IS FIGHTING THE VWS SOMEWHAT WITH SHORT-LIVED 
UPSHEAR PULSES OF OUTFLOW. DUE TO THE LACK OF MICROWAVE IMAGERY, IT 
IS DIFFICULT TO ASSESS THE CONVECTIVE STRUCTURE AND ASCERTAIN THE 
INITIAL POSITION WITH ANY CONFIDENCE. THE INITIAL INTENSITY IS 
ASSESSED AT 55 KNOTS BASED ON THE MORE REALISTIC T3.5 (55 KNOTS) 
DVORAK ESTIMATES, WHICH ARE CONSISTENT WITH THE CIMSS OBJECTIVE
INTENSITY ESTIMATES.

INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK 

CURRENT STEERING MECHANISM: DEEP-LAYERED SUBTROPICAL RIDGE (STR)
ENTRENCHED TO THE NORTH.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T3.5 - 55 KTS
   RJTD: T4.5 - 77 KTS
   RCTP: T3.5 - 55 KTS
   KNES: T3.5 - 55 KTS
   CIMSS SATCON: 54 KTS AT 241636Z
   CIMSS ADT: 57 KTS AT 241740Z
   CIMSS AIDT: 48 KTS AT 241740Z
   CIMSS D-MINT: 46 KTS AT 241705Z
   CIMSS D-PRINT: 55 KTS AT 241920Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
   VWS: 20-25 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: MODERATE POLEWARD AND EQUATORWARD

ANALYSIS CONFIDENCE:
   INITIAL POSITION: LOW
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TROPICAL STORM (TS) 26W WILL TRACK WEST-
NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF THE STR THROUGH
TAU 72. A SLIGHT INCREASE TO 60 KNOTS IS EXPECTED PRIOR TO LANDFALL
THEN A SHORT PERIOD OF WEAKENING AS THE SYSTEM TRACKS ACROSS THE
CENTRAL PHILIPPINE ISLANDS. AFTER EMERGING BACK OVER WATER NEAR TAU
48, TS 26W IS FORECAST TO GRADUALLY INTENSIFY TO TYPHOON STRENGTH
BY TAU 96. THE SYSTEM WILL TURN MORE NORTHWESTWARD AS IT TRACKS
ALONG THE SOUTHWESTERN PERIPHERY OF THE STR, WITH LANDFALL OVER 
NORTHERN VIETNAM EXPECTED BY ABOUT TAU 120. 

MODEL DISCUSSION: WITH THE EXCEPTION OF NAVGEM AND JGSM, THE 
DETERMINISTIC GUIDANCE IS IN FAIR AGREEMENT SUPPORTING THE JTWC
FORECAST TRACK WITH MEDIUM CONFIDENCE. RELIABLE INTENSITY GUIDANCE
SUPPORTS THE REINTENSIFICATION PHASE OVER THE SOUTH CHINA SEA, WITH
A LARGE SPREAD IN PEAK INTENSITY VALUES. HAFS-A AND COAMPS-TC (GFS)
INDICATE A MORE MODEST PEAK INTENSITY OF 55-60 KNOTS AT TAU 84. 

FORECAST CONFIDENCE:
   TRACK 00-72 HR: MEDIUM
   TRACK 72-120 HR: MEDIUM
   INTENSITY 00-72 HR: MEDIUM
   INTENSITY 72-120 HR: MEDIUM//
NNNN