WDPN32 PGTW 222100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 10W (TEN) WARNING NR 
003//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 19.9N 130.8E
   INITIAL INTENSITY: 30 KTS
   GEOGRAPHIC REFERENCE: 429 NM SOUTH-SOUTHEAST OF KADENA AB
   MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 10 KTS
   SIGNIFICANT WAVE HEIGHT: 12 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
TROPICAL DEPRESSION (TD) 10W REMAINS EMBEDDED WITHIN THE NORTHEASTERN 
PERIPHERY OF A LARGE, APPROXIMATELY 650NM DIAMETER LOW PRESSURE AREA, 
WHICH IS FORECAST TO GRADUALLY DEEPEN AND STRENGTHEN INTO A MONSOON 
DEPRESSION WITH EXPANSIVE GALE FORCE WINDS OVER THE NEXT 24 TO 48 
HOURS. THIS COMPLEX SYNOPTIC PATTERN IS EVIDENT IN THE CIMSS TOTAL 
PRECIPITABLE WATER (TPW) ANIMATION, WITH MULTIPLE TROPICAL SYSTEMS 
ROTATING CYCLONICALLY ALONG THE PERIPHERY (10W AND INVESTS 99W, 90W). 
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A PARTIALLY 
EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC) POSITIONED ALONG THE 
WESTERN EDGE OF THE CONVECTIVE MASS. THE INITIAL POSITION IS PLACED 
WITH MEDIUM CONFIDENCE BASED ON THE EIR IMAGERY. A 221759Z GMI 37GHZ 
COLOR COMPOSITE MICROWAVE IMAGE REVEALS CURVED CONVECTIVE BANDING OVER 
THE EASTERN SEMICIRCLE WRAPPING INTO THE LLCC. ENVIRONMENTAL 
CONDITIONS ARE FAVORABLE, WITH ENHANCED POLEWARD OUTFLOW EVIDENT IN 
ANIMATED WATER VAPOR IMAGERY, LOW VERTICAL WIND SHEAR AND WARM (29-
30C) SST VALUES. THERE IS SOME PRESSURE ON THE SOUTHWESTERN FLANK OF 
THE SYSTEM ASSOCIATED WITH INVEST 90W'S OUTFLOW, WHICH IS HINDERING 
EQUATORWARD OUTFLOW. THE INITIAL INTENSITY OF 30 KTS IS ASSESSED WITH 
MEDIUM CONFIDENCE BASED ON THE KNES AND PGTW DVORAK ESTIMATES AS WELL 
AS RECENT ASCAT DATA. CIMSS OBJECTIVE INTENSITY ESTIMATES RANGE FROM 
25 TO 38 KNOTS.

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

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE POSITIONED TO THE
EAST AND NORTH, WITH LARGE CYCLONIC FLOW PATTERN, AND EXTENSIVE
WESTERLIES FROM SOUTHEAST ASIA TO THE EAST PHILIPPINE SEA.   

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.0 - 30 KTS
   RJTD: T1.5 - 25 KTS
   KNES: T2.0 - 30 KTS
   CIMSS SATCON: 39 KTS AT 221635Z
   CIMSS ADT: 34 KTS AT 221730Z
   CIMSS AIDT: 36 KTS AT 221730Z
   CIMSS D-MINT: 31 KTS AT 221635Z
   CIMSS D-PRINT: 29 KTS AT 221730Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 10-15 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: MODERATE POLEWARD

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TD 10W IS FORECAST TO CONTINUE TO TRACK NORTH-
NORTHWESTWARD TO NORTHWESTWARD AROUND THE NORTHEASTERN AND NORTHERN 
PERIPHERY OF THE LARGE LOW PRESSURE AREA OR DEVELOPING MONSOON 
DEPRESSION THROUGH TAU 48. THE SYSTEM IS EXPECTED TO INTENSIFY SLOWLY 
TO A PEAK OF 40 KNOTS BY TAU 24, MAINTAINING 40 KNOTS THROUGH TAU 48. 
TD 10W IS EXPECTED TO MAINTAIN TROPICAL CHARACTERISTICS, WITH A RADIUS 
OF MAXIMUM WINDS UNDER 100NM AND CORE CONVECTION AT LEAST THROUGH TAU 
36. AFTER TAU 36, AS THE SYSTEM APPROACHES OKINAWA, IT WILL BEGIN TO 
GRADUALLY MERGE INTO THE MONSOON DEPRESSION CENTER, WITH EXTENSIVE 
GALE FORCE WINDS DISPLACED OVER THE EASTERN AND NORTHERN FLANK OF THE
SYSTEM. THE EXACT TIMING OF THIS TRANSITION IS DIFFICULT TO PINPOINT 
BUT COULD OCCUR EARLIER. HOWEVER, THE OVERALL WIND IMPACTS TO OKINAWA 
WILL REMAIN CONSISTENT REGARDLESS.    

MODEL DISCUSSION: AS DISCUSSED EARLIER, THIS SYNOPTIC PATTERN IS
EXTREMELY COMPLEX AND CHALLENGING. THEREFORE, JTWC TRACK CONFIDENCE
REMAINS LOW. DETERMINISTIC GUIDANCE IS IN POOR AGREEMENT, WITH A
230NM CROSS-TRACK SPREAD AT TAU 36. THE BULK OF THE TRACKERS ARE
SOUTH OF THE JTWC FORECAST TRACK AND CONTINUE TO TRACK THE BROAD
MONSOON DEPRESSION CENTER. THE JTWC TRACK FORECAST CONTINUES TO
FAVOR THE ECMWF AND ECENS TRACKERS BUT ARE SPECIFICALLY TRACKING A
DISCRETE LOW-LEVEL VORTICITY MAXIMUM WITHIN THE NORTHERN PORTION OF
THE BROAD LOW PRESSURE CENTER. THIS PREFERENCE FOR THE ECMWF MODELS
IS BASED ON THE SUPERIOR PERFORMANCE OF THE MODEL IN THE DEVELOPMENT 
STAGE AND INITIAL TRACK TO THIS POINT. THE JTWC TRACK FORECAST REMAINS 
CONSISTENT WITH THE PREVIOUS FORECAST, WITH SOME MINOR ADJUSTMENTS 
BASED ON THE 221800Z INITIAL POSITION. AS A CONSEQUENCE, THE CPA TO 
KADENA HAS INCREASED FROM 60NM TO 78NM. DUE TO THE NATURE OF THE 
SYSTEM AND ITS EXPECTED EVOLUTION OVER THE NEXT FEW DAYS, SHIFTS IN 
BOTH THE INITIAL POSITION AND TRACK ARE VERY LIKELY. THE 221200Z ECENS 
SHOWS A SIMILAR SWATH OF SOLUTIONS OVER AND TO THE SOUTH OF OKINAWA, 
WITH A GENERAL TRACK TOWARD EASTERN CHINA SOUTH OF 30N LATITUDE. THE 
221200Z GEFS ENSEMBLE INDICATES MORE UNCERTAINTY IN THE TRACK 
ESPECIALLY AFTER PASSING WEST OF OKINAWA. 
   
FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: LOW
   INTENSITY 0 - 72 HR: MEDIUM//
NNNN