WDPN32 PGTW 230300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 05W (GAEMI) WARNING NR 014//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 20.0N 124.9E
   INITIAL INTENSITY: 80 KTS
   GEOGRAPHIC REFERENCE: 359 NM SOUTHEAST OF TAIPEI, TAIWAN
   MOVEMENT PAST 6 HOURS: NORTHWARD AT 16 KTS
   SIGNIFICANT WAVE HEIGHT: 35 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS STRONG CLOUD
BANDING WRAPPING FULLY AROUND THE SYSTEM AND INTO THE VORTEX OF
TYPHOON (TY) 05W. OVERSHOOTING TOPS OBSCURE THE CENTER OF THE
SYSTEM THAT PREVIOUSLY HINTED AT DEVELOPING AN EYE STRUCTURE. A F17
SSMIS 91GHZ MICROWAVE IMAGE FROM 222230Z DEPICTS A DISTINCT
MICROWAVE EYE WITH A LARGE SWATH OF UPPER-LEVEL CONVECTION TO THE
SOUTHEAST, BUT MINIMAL CONVECTION LOCATED TO THE NORTHWEST DUE TO
DRY AIR AND MODERATE VERTICAL WIND SHEAR (VWS) OF 15-20KTS. THE
INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE
AFOREMENTIONED ANIMATED MSI AND EYE STRUCTURE DEPICTED ON MICROWAVE
IMAGERY. THE SYSTEM HAS DRASTICALLY INTENSIFIED OVER THE LAST 12
HOURS AND THE INITIAL INTENSITY OF 80 KTS IS ASSESSED WITH MEDIUM
CONFIDENCE BASED ON THE AGENCY AND OBJECTIVE FIXES LISTED BELOW.

INITIAL WIND RADII BASIS: PERSISTENCE 

CURRENT STEERING MECHANISM: THE WESTERN PERIPHERY OF A SUBTROPICAL
RIDGE (STR) TO THE EAST.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T4.5 - 77 KTS
   RJTD: T5.0 - 90 KTS
   RCTP: T4.5 - 77 KTS
   KNES: T4.5 - 77 KTS
   CIMSS SATCON: 82 KTS AT 0100Z
   CIMSS ADT: 79 KTS AT 0100Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 10-15 KTS
   SST: 30-31 CELSIUS
   OUTFLOW: STRONG POLEWARD AND EQUATORWARD

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 05W IS FORECAST TO CONTINUE TO TRACK
NORTH-NORTHWESTWARD ON THE EASTERN EDGE OF A SUBTROPICAL RIDGE TO
THE EAST BEFORE CURVING TO A NORTHWESTWARD TRACK AT TAU 24. THE
SYSTEM WILL CONTINUE TO TRACK IN THAT DIRECTION BEFORE ALTERING
COURSE BACK TO A NORTH-NORTHWESTERLY TRACK BY TAU 96. FURTHER
INTENSIFICATION IS FORECASTED OVER THE NEXT 24 HOURS WITH THE
POTENTIAL TO REACH A PEAK INTENSITY BETWEEN 24 AND 36 HOURS
SUPPORTED BY FAVORABLE UPPER-LEVEL DIVERGENCE, ELEVATED OCEAN HEAT
CONTENT, SEA SURFACE TEMPERATURES ABOVE 30C, AND LOW TO MODERATE
VERTICAL WIND SHEAR. AT TAU 36, THE SYSTEM WILL INTERACT WITH THE
TOPOGRAPHY OF MAINLAND TAIWAN, CAUSING VERTICAL WIND SHEAR TO
INCREASE TO LEVELS BETWEEN 25-30KTS AND WEAKEN THE STRUCTURE OF THE
SYSTEM. TY 05W WILL CONTINUE TO WEAKEN AS THE SYSTEM COMES OUT OVER
THE TAIWAN STRAIT AND CONTINUE TO WEAKEN UNDER ELEVATED 25-30KT
SHEAR. AFTER LANDFALL BETWEEN TAU 48-72, THE SYSTEM WILL CONTINUE
TO DISSIPATE OVER LAND THROUGH THE END OF THE FORECAST.

MODEL DISCUSSION: DETERMINISTIC MODEL GUIDANCE IS IN STRONG
AGREEMENT AS TO THE OVERALL NORTHWESTWARD TRACK THAT TY 05W WILL
TAKE OVER THE NEXT 72 HOURS, BUT THE DEGREE OF HOW STRONGLY LAND
INTERACTION WILL INFLUENCE THE TRACK DIFFERS AMONGST JTWC CONSENSUS
MEMBERS. OVERALL, THE CONSENSUS MEMBERS CURVE THE SYSTEM
NORTHEASTWARD AFTER TAU 48, HOWEVER, NAVGEM AND UKMET FORECAST A
SYSTEM TRACK SOUTHWESTWARD. THE JTWC GUIDANCE IS IN GOOD AGREEMENT
THAT TY 05W WILL PEAK BY TAU 24 AND WEAKEN DUE TO ELEVATED VERTICAL
WIND SHEAR AND LAND INTERACTION. THE RAPID INTENSIFICATION AIDS
TRIGGER AS WELL FOR THE FIRST 24 HOURS, WHICH IS POSSIBLE DUE TO
THE FAVORABLE ENVIRONMENT AND HIGH OCEAN HEAT CONTENT LEVELS
INDICATED THROUGH TAU 24.

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