WDPN31 PGTW 270300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 01W (EWINIAR) WARNING NR 010//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 15.8N 122.8E
   INITIAL INTENSITY: 90 KTS
   GEOGRAPHIC REFERENCE: 700 NM SOUTH-SOUTHWEST OF KADENA AB
   MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 04 KTS
   SIGNIFICANT WAVE HEIGHT: 26 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TYPHOON
(TY) 01W (EWINIAR) EXHIBITING A FURTHER CONSOLIDATING STRUCTURE, WITH 
DEEP CONVECTIVE BANDING PREVALENT MOSTLY IN THE NORTHEASTERN QUADRANT. 
THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON A 270000Z 
HIMAWARI 1KM VISIBLE SATELLITE IMAGE. IN ANIMATED IMAGERY, THE ONCE 
EVIDENT PINHOLE EYE FEATURE HAS OBSCURED, PRESENTING A DIMPLE IN THE 
CIRRUS CANOPY OVERHEAD OF THE LLCC. THE OVERALL ENVIRONMENT IS 
ASSESSED AS HIGHLY FAVORABLE, WITH PERSISTING
POLEWARD OUTFLOW ALOFT, VERY WARM (30-31C) SEA SURFACE
TEMPERATURES, AND LOW (5-10 KTS) VERTICAL WIND SHEAR. THE INITIAL 
INTENSITY OF 90 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON 
SUBJECTIVE AND OBJECTIVE INTENSITY ESTIMATES LISTED BELOW.

INITIAL WIND RADII BASIS: PERSISTENCE 

CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A SUBTROPICAL
RIDGE

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T5.5 - 102 KTS
   RCTP: T5.0 - 90 KTS
   KNES: T5.0 - 90 KTS
   CIMSS ADT: 92 KTS AT 262330Z
   CIMSS AIDT: 88 KTS AT 262330Z
   CIMSS DPRINT: 83 KTS AT 262330Z
   CIMSS DMINT: 88 KTS AT 262330Z
   CIMSS SATCON: 84 KTS AT 262330Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE
   VWS: 5-10 KTS
   SST: 30-31 CELSIUS
   OUTFLOW: MODERATE POLEWARD

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   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: TY 01W IS FORECAST TO CONTINUE TRACKING
NORTH-NORTHEASTWARD, STEERED BY A SUBTROPICAL RIDGE (STR) LOCATED
EAST OF THE LLCC FROM TAU 00 TO TAU 12, FOLLOWED BY A SLIGHT TURN
TO A MORE NORTHEASTWARD TRACK FROM TAU 12 TO TAU 120. INTENSITY IS
FORECAST TO CONTINUE INCREASING UNTIL TAU 24, DUE TO THE
AFOREMENTIONED HIGHLY FAVORABLE ENVIRONMENT. AFTER TAU 36, OCEAN HEAT 
CONTENT SHARPLY DECREASES AND SEA SURFACE TEMPERATURES FALL BELOW 26C 
BY TAU 72. VERTICAL WIND SHEAR IS EXPECTED TO INCREASE TO 33 KTS BY 
TAU 96 AS THE SYSTEM BEGINS EXTRATROPICAL TRANSITION. TY 01W IS 
FORECAST TO COMPLETE EXTRATROPICAL TRANSITION NO LATER THAN TAU 120.

MODEL DISCUSSION: GLOBAL NUMERICAL MODEL GUIDANCE EXHIBITS GOOD
TRACK AGREEMENT, WITH A CROSS-TRACK SPREAD OF 128NM AT TAU 72 WITH
THE EXCEPTION OF JAPANESE GLOBAL SPECTRAL MODEL SHOWING A SLIGHTLY
MORE EASTERLY TRACK. BEYOND TAU 72, MODELS DIVERGE MAINLY IN REGARD
TO SPEED ASSESSMENT, WITH A 415NM ALONG-TRACK SPREAD BY TAU 120
BETWEEN NAVGEM AND ECMWF ENSEMBLE MEAN. MODEL GUIDANCE EXHIBITS
GOOD AGREEMENT ON INTENSITY, SHOWING INTENSIFICATION TO A PEAK OF
105 KTS AT TAU 24. FOLLOWING A BRIEF SUSTAINMENT PERIOD TO TAU 36,
A WEAKENING TREND ONSETS AS THE ENVIRONMENT BECOMES UNFAVORABLE. 
RAPID INTENSIFICATION (RI) AIDS HAVE DECREASED IN PROBABILITY OF
OCCURRENCE, WITH ONE CAVEAT FOR COAMPS TC, WHICH IS ASSESSING RI
PROBABILITY AT 40 PERCENT LIKELIHOOD OF OCCURRENCE BETWEEN TAU 12 AND 
TAU 36.

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