WDPN31 PGTW 240300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 26W (BUALOI) WARNING NR 
003//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 9.5N 133.0E
   INITIAL INTENSITY: 40 KTS
   GEOGRAPHIC REFERENCE: 156 NM NORTH-NORTHWEST OF KOROR
   MOVEMENT PAST 6 HOURS: WESTWARD AT 07 KTS
   SIGNIFICANT WAVE HEIGHT: 18 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS INCREASINGLY
ORGANIZED DEEP CONVECTIVE BANDING OVER THE NORTHWESTERN AND SOUTHERN
PORTIONS OF A LOW-LEVEL CIRCULATION ALSO EVIDENT IN 232211Z SSMIS
IMAGERY. A FAVORABLE FLOW PATTERN ALOFT, INCLUDING ENHANCED POLEWARD
OUTFLOW TOWARD AN UPPER-LEVEL LOW TO THE NORTH, CONTINUES TO DRIVE
STORM DEVELOPMENT. THE INITIAL POSITION IS PLACED WITH MEDIUM
CONFIDENCE BASED ON 232330Z PGTW AND KNES SATELLITE FIXES, THE
AFOREMENTIONED SSMIS IMAGERY, AND A PARTIAL 240002Z METOP-C ASCAT
PASS. THE INITIAL INTENSITY OF 40 KTS IS ASSESSED WITH MEDIUM
CONFIDENCE BASED ON THE 240002Z ASCAT DATA, WHICH INDICATES AN
EXTENSIVE AREA OF 35 TO 40 KNOT SURFACE WINDS TO THE NORTHWEST OF THE 
CENTER.

INITIAL WIND RADII BASIS: 240002Z METOP-B ASCAT SCATTEROMETER DATA
AND OBJECTIVE BEST TRACK 

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE TO THE NORTH

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.5 - 35 KTS
   RJTD: T2.5 - 35 KTS
   RCTP: T2.5 - 35 KTS
   KNES: T2.5 - 35 KTS
   CIMSS SATCON: 35 KTS AT 232212Z
   CIMSS ADT: 34 KTS AT 232040Z
   CIMSS AIDT: 33 KTS AT 232040Z
   CIMSS D-MINT: 27 KTS AT 232211Z
   CIMSS D-PRINT: 31 KTS AT 240040Z

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

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: 26W IS EXPECTED TO TRACK GENERALLY
WEST-NORTHWESTWARD THROUGHOUT THE FORECAST PERIOD UNDER THE
CONTINUOUS STEERING INFLUENCE OF SUBTROPICAL RIDGING TO THE NORTH.
STEADY INTENSIFICATION SHOULD OCCUR OVER THE NEXT 24 TO 36 HOURS
AIDED BY LOW TO MODERATE VERTICAL WIND SHEAR, FAVORABLE OUTFLOW
ALOFT, AND PASSAGE OVER VERY WARM WATER. HOWEVER, THE UPPER-LEVEL
LOW CURRENTLY ANALYZED TO THE NORTH OF 26W WILL QUICKLY TRANSLATE
WESTWARD, AWAY FROM THE SYSTEM. IN ITS WAKE, THE PERIPHERAL FLOW
AROUND A BUILDING UPPER-LEVEL RIDGE TO THE NORTH WILL INDUCE
INCREASING VERTICAL WIND SHEAR OVER THE SYSTEM BY TAU 36. THIS
SHEAR, COMBINED WITH PASSAGE OVER LAND, ARE EXPECTED TO WEAKEN THE
SYSTEM BETWEEN TAUS 36 AND 72. THEREAFTER, REINTENSIFICATION IS
LIKELY IN THE SOUTH CHINA SEA AS THE SYSTEM PASSES OVER WARM WATER
AND VERTICAL WIND SHEAR TAPERS. 

MODEL DISCUSSION: CONSENSUS AND ENSEMBLE MODEL TRACK GUIDANCE IS IN
GOOD AGREEMENT THROUGH TAU 72 IN TERMS OF BOTH DIRECTION AND SPEED
OF MOTION. SPREAD INCREASES AFTER TAU 72 DUE TO DIFFERING 
REPRESENTATIONS OF THE STEERING RIDGE ORIENTATION AND INTENSITY OF 
THE SYSTEM. HOWEVER, SPREAD IN THE EXTENDED PERIOD IS NOT AS LARGE AS 
THE PREVIOUS CYCLE AND NEARLY ALL MODELS, EXCEPT FOR NAVGEM AND JGSM, 
DEPICT A TRACK TO THE SOUTH AND WEST OF HAINAN ISLAND BETWEEN TAUS 96 
AND 120. THE CURRENT JTWC TRACK FORECAST IS CONSISTENT WITH THE
PREVIOUS FORECAST AND IS SITUATED SLIGHTLY TO THE SOUTH OF THE
MULTI-MODEL CONSENSUS, WITHIN THE PRIMARY GROUPING. MODEL INTENSITY
FORECASTS ARE IN BROAD AGREEMENT REGARDING THE OVERALL TREND,
INCLUDING NEAR-TERM INTENSIFICATION THROUGH TAU 36 FOLLOWED BY A
PERIOD OF MODERATE WEAKENING AND ENDING WITH REINTENSIFICATION OVER
THE SOUTH CHINA SEA. THE CURRENT INTENSITY FORECAST LIES NEAR THE
MID POINT OF THE RELATIVELY NARROW CONSENSUS MODEL ENVELOPE.

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