WDPN33 PGTW 262100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 11W (CO-MAY)   
WARNING NR 016//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 26.8N 127.4E
   INITIAL INTENSITY: 25 KTS
   GEOGRAPHIC REFERENCE: 28 NM NORTHWEST OF KADENA AB
   MOVEMENT PAST 6 HOURS: EAST-SOUTHEASTWARD AT 05 KTS
   SIGNIFICANT WAVE HEIGHT: 13 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS AN EXPOSED 
LOW-LEVEL CIRCULATION (LLC), WITH FLARING DEEP CONVECTIVE BURSTS ALONG 
THE SOUTHERN AND EASTERN PERIPHERIES. ANIMATED RADAR IMAGERY REVEALS 
WEAK BANDING WRAPPING INTO AN ELONGATED LLC, WITH FRAGMENTED OUTER 
BANDING. SURFACE OBSERVATIONS SUPPORT THE INITIAL POSITION WEST OF 
OKINAWA, WITH MAXIMUM WINDS OF 21 KNOTS (10-MINUTE AVERAGE) REPORTED 
AT KITAHARA. THE INITIAL POSITION IS ASSESSED WITH MEDIUM CONFIDENCE 
BASED ON RADAR IMAGERY, EIR IMAGERY AND SURFACE OBSERVATIONS. THE 
INITIAL INTENSITY OF 25 KNOTS IS ASSESSED WITH HIGH CONFIDENCE BASED 
ON SURFACE OBSERVATIONS AND RECENT ASCAT DATA. ENVIRONMENTAL 
CONDITIONS ARE MARGINALLY FAVORABLE, WITH MODERATE EQUATORWARD OUTFLOW 
AND WEAK POLEWARD OUTFLOW, INHIBITED BY A TUTT CELL POSITIONED TO THE 
NORTHWEST AND DRY AIR ENTRAINMENT OFFSET BY LOW VERTICAL WIND SHEAR 
AND WARM SST VALUES. 

INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).

CURRENT STEERING MECHANISM: COMPETING STEERING ENVIRONMENT, WITH
SUBTROPICAL RIDGE (STR) TO THE EAST AND NORTH AND NEAR-EQUATORIAL
RIDGE (NER) TO THE SOUTH.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T1.5 - 25 KTS
   CIMSS SATCON: 44 KTS AT 261658Z
   CIMSS ADT: 32 KTS AT 261730Z
   CIMSS AIDT: 35 KTS AT 261730Z
   CIMSS D-MINT: 25 KTS AT 261658Z
   CIMSS D-PRINT: 22 KTS AT 261800Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
   VWS: 10-15 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: MODERATE EQUATORWARD
   OTHER FACTORS: DRY AIR ENTRAINMENT

ANALYSIS CONFIDENCE:
   INITIAL POSITION: MEDIUM
   INITIAL INTENSITY: HIGH
   INITIAL WIND RADII: NOT APPLICABLE

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: MAJOR CHANGE TO THE JTWC FORECAST,
WITH SYSTEM NOW EXPECTED TO REINTENSIFY AND TRACK OVER EASTERN
CHINA.

FORECAST DISCUSSION: TROPICAL DEPRESSION (TD) 11W IS FORECAST TO
TRACK SLOWLY EAST-NORTHEASTWARD THROUGH TAU 12 THEN TURN SHARPLY
NORTHWESTWARD TO WEST-NORTHWESTWARD AS THE STR TO THE NORTH BECOMES
THE DOMINANT STEERING INFLUENCE. THE SYSTEM WILL GRADUALLY INTENSIFY 
TO 30 KNOTS BY TAU 24. AFTER TAU 24, TD 11W WILL ACCELERATE WEST-
NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF THE STR THROUGH 
LANDFALL, WHICH WILL OCCUR SOUTH OF SHANGHAI NEAR TAU 60. TD 11W WILL 
SLOWLY INTENSIFY DUE TO DRY AIR ENTRAINMENT. HOWEVER, THE SYSTEM IS 
EXPECTED TO RE-MOISTEN JUST PRIOR TO LANDFALL, WITH A PEAK INTENSITY 
OF 45 KNOTS NEAR TAU 60. AFTER LANDFALL, THE SYSTEM WILL RECURVE 
POLEWARD OVERLAND TOWARD A BREAK IN THE STR TO THE NORTH, WITH STEADY 
WEAKENING AND DISSIPATION EXPECTED.   

MODEL DISCUSSION: DETERMINISTIC MODEL GUIDANCE IS IN FAIR AGREEMENT, 
WITH A 110NM CROSS-TRACK SPREAD AT TAU 48. THE DETERMINISTIC AND 
ENSEMBLE MODELS DIVERGE THROUGH THE REMAINDER OF THE JTWC FORECAST, 
WITH MEDIUM OVERALL CONFIDENCE IN THE JTWC TRACK FORECAST. RELIABLE 
INTENSITY GUIDANCE INDICATES A PEAK INTENSITY RANGING FROM 35 TO 45 
KNOTS BETWEEN TAU 36 TO TAU 60.  

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: MEDIUM
   TRACK 72-120 HR: MEDIUM
   INTENSITY 0 - 72 HR: MEDIUM
   INTENSITY 72-120 HR: MEDIUM//
NNNN