WDPN31 PGTW 302100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 14W (KOINU) WARNING NR 
006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 16.8N 130.0E
   INITIAL INTENSITY: 45 KTS
   GEOGRAPHIC REFERENCE: 536 NM EAST-NORTHEAST OF MANILA,
PHILIPPINES
   MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 07 KTS
   SIGNIFICANT WAVE HEIGHT: 19 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) AND PROXY VISIBLE IMAGERY DEPICT A
BROAD AND CONSOLIDATING SYSTEM WITH DEEP CONVECTION OVER THE
SOUTHERN SEMICIRCLE WRAPPING INTO AND OBSCURING THE LOW-LEVEL
CIRCULATION CENTER (LLCC). A 301714Z GMI 89GHZ MICROWAVE IMAGE
REVEALS A BROAD LLCC POSITIONED ALONG THE NORTHEASTERN EDGE OF A
CURVED SPIRAL BAND. THE INITIAL POSITIONED IS PLACED WITH MODERATE
CONFIDENCE BASED ON THE EIR AND GMI MICROWAVE IMAGERY. THE INITIAL
INTENSITY OF 45 KTS IS ASSESSED WITH HIGH CONFIDENCE BASED ON
MULTIPLE AGENCY FIXES IN THE T2.5-3.0 RANGE IN COMBINATION WITH ADT
AND SATCON ESTIMATES OF 45 AND 47 KNOTS, RESPECTIVELY. RECENT
DPRINT AND DMINT ESTIMATES RANGING FROM 45 TO 49 KNOTS. ANALYSIS
INDICATES A FAVORABLE ENVIRONMENT WITH MODERATE EQUATORWARD
OUTFLOW, WARM SSTS, AND FAVORABLE (10-15 KNOTS) VERTICAL WIND
SHEAR.

INITIAL WIND RADII BASIS: PERSISTENCE 

CURRENT STEERING MECHANISM: DEEP-LAYERED SUBTROPICAL RIDGE (STR)
POSITIONED TO THE NORTHEAST

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T3.0 - 45 KTS
   RJTD: T2.5 - 35 KTS
   KNES: T2.5 - 35 KTS
   CIMSS SATCON: 47 KTS AT 301627Z
   CIMSS ADT: 45 KTS AT 301730Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 10-15 KTS
   SST: 30-31 CELSIUS
   OUTFLOW: MODERATE 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: TS 14W IS TRACKING GENERALLY
WEST-NORTHWESTWARD ALONG THE SOUTHWESTERN PERIPHERY OF THE
SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTHEAST, AND WILL
GRADUALLY TURN NORTHWESTWARD THROUGH TAU 12. THE STR IS EXPECTED TO
REALIGN TO THE NORTHEAST WHILE A WEAK MID-LATITUDE SHORTWAVE TROUGH
WILL WEAKEN THE STR ENOUGH TO ALLOW 14W TO GAIN LATITUDE AND TRACK
NORTHWESTWARD THROUGH TAU 72. AFTER TAU 72, THE STR IS EXPECTED TO
BUILD AND REORIENT THE TRACK WEST-NORTHWESTWARD TOWARDS SOUTHERN
TAIWAN. IN TERMS OF INTENSITY, TS 14W WILL STEADILY INTENSIFY
THROUGH TAU 36 AS SHEAR AND MOISTURE ENVIRONMENTAL CONDITIONS WILL
REMAIN FAVORABLE. BETWEEN TAU 48 AND TAU 96, RAPID INTENSIFICATION
CHANCES INCREASE AS THE SYSTEM COULD TAP INTO DUAL CHANNEL OUTFLOW
ALONG WITH WARM (30-31C) SSTS AND HIGH OCEAN HEAT CONTENT. BY TAU
120, AS THE SYSTEM IS EXPECTED TO MAINTAIN A PEAK OF 110 KTS WHILE 
PASSING SOUTH OF TAIWAN. 

MODEL DISCUSSION: NAVGEM REMAINS THE SOLE OUTLIER RIGHT OF TRACK,
WHILE THE BULK OF THE DETERMINISTIC GUIDANCE REMAINS IN FAIR
AGREEMENT WITH ONLY A 35 TO 75NM SPREAD IN SOLUTIONS FROM TAU 12 TO
TAU 72. AFTER TAU 72 AND FOR THE REMAINING TRACK, THE MODEL
GUIDANCE ONLY SPREADS TO 130NM UNTIL THE END OF THE FORECAST
PERIOD. THEREFORE, THERE IS HIGH CONFIDENCE THROUGH TAU 24 AND
MEDIUM CONFIDENCE THEREAFTER AS THE SPREAD INCREASE. THERE IS
MEDIUM CONFIDENCE IN THE OVERALL JTWC INTENSITY FORECAST AS ALL 
MEMBERS SHOW STEADY INTENSIFICATION. ADDITIONALLY, RAPID 
INTENSIFICATION AIDS ARE REFLECTING A CONDUCIVE RI ENVIRONMENT 
CHARACTERIZED BY ROBUST DUAL CHANNEL OUTFLOW, LOW VERTICAL WIND SHEAR, 
AND WARM SST VALUES. AFTER TAU 72, INTENSITY MODEL GUIDANCE INCREASES 
IN SPREAD WITH COAMPS-TC INDICATING A PEAK NEAR 135 KTS, WHILE DECAY 
SHIPS AND GFS REPRESENT THE LOW END OF THE GUIDANCE ENVELOPE. 

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