WDPN31 PGTW 030900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 27W (MATMO) WARNING NR 009//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 17.0N 120.9E
   INITIAL INTENSITY: 65 KTS
   GEOGRAPHIC REFERENCE: 144 NM NORTH OF MANILA, PHILIPPINES
   MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 14 KTS
   SIGNIFICANT WAVE HEIGHT: 28 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS DEEP
CONVECTIVE BANDING PATTERN WRAPPING INTO THE LOW-LEVEL CIRCULATION
CENTER (LLCC) OF TYPHOON (TY) 27W (MATMO), WHILE THE SYSTEM
TRANSITS OVER NORTHERN LUZON, PHILIPPINES. IMPRESSIVE CENTRAL DENSE
OVERCAST AND ASSOCIATED FEEDING BANDS EXTEND WELL BEYOND THE
PERIMETER OF THE ISLAND. AS THE CENTER OF THE SYSTEM APPROACHES THE 
SOUTH CHINA SEA, IT WILL REMAIN EMBEDDED IN A FAVORABLE SYNOPTIC 
ENVIRONMENT, CHARACTERIZED BY ENHANCED RADIAL OUTFLOW RESULTING FROM 
UPPER-LEVEL DIVERGENCE, WITH A PARTICULARLY STRONG WESTWARD 
COMPONENT, SEA SURFACE TEMPERATURES (SST) BETWEEN 29-30 C SURROUNDING 
LUZON, LOW VERTICAL WIND SHEAR (5-10 KTS), AND A MOIST TROPOSPHERIC 
COLUMN, WHICH SUPPORTS SUSTAINED DEEP CONVECTION. THE INITIAL 
POSITION IS ESTIMATED WITH MEDIUM CONFIDENCE AND IS DERIVED FROM A 
COMBINATION OF RADAR AND SHORTWAVE INFRARED SATELLITE IMAGERY. THE 
INITIAL INTENSITY IS ASSESSED AT 65 KTS WITH MEDIUM CONFIDENCE, BASED 
ON THE OBJECTIVE SATELLITE-DERIVED INTENSITY ESTIMATES LISTED BELOW,
CONSISTENT WITH STRUCTURALLY SOUND VORTEX AND THE ANATOMY OF THE
SURROUNDING COMPONENTS OF TY MATMO.

INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK 

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) CENTERED TO THE
NORTH

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: NO CURRENT ESTIMATE
   RJTD: T3.5 - 55 KTS
   CIMSS D-MINT: 75 KTS AT 030524Z
   CIMSS D-PRINT: 60 KTS AT 030630Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 5-10 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: STRONG WESTWARD
   OTHER FACTORS: VORTEX IS CURRENTLY CENTERED OVER LAND

ANALYSIS CONFIDENCE:
   INITIAL POSITION: MEDIUM
   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 27W IS EXPECTED TO CONTINUE TRACKING
NORTHWESTWARD UNDER THE INFLUENCE OF A PERSISTENT SUBTROPICAL RIDGE
(STR) LOCATED TO THE NORTH. INTERACTION WITH THE RUGGED TERRAIN OVER 
LUZON IS CAUSING SOME FRICTIONAL DISRUPTION TO THE LOW-LEVEL INFLOW, 
HOWEVER THE SYSTEM BEING FED BY OUTER BANDS REMAINING OVER WARM WATER 
DOES NOT APPEAR TO BE PARTICULARLY AFFECTED. SUBSEQUENTLY, TY MATMO 
IS FORECAST TO RE-EMERGE OVER THE SOUTH CHINA SEA WITHIN THE NEXT FEW 
HOURS. ENVIRONMENTAL CONDITIONS, INCLUDING SST VALUES (28-29 C) WILL
REMAIN CONDUCIVE TO RE-INTENSIFICATION. TY MATMO IS EXPECTED TO
TRACK ALONG THE SOUTHERN PERIPHERY OF A STR TO THE NORTH TOWARD THE
CHINESE COAST. THE SYNOPTIC ENVIRONMENT IS FORECAST TO REMAIN
FAVORABLE FOR INTENSIFICATION, WITH PEAK INTENSITY EXPECTED TO
REACH 85 KTS BEFORE FINAL LANDFALL. THE CURRENT TRACK FORECAST
SUGGESTS A PRIMARY LANDFALL JUST NORTH OF HAINAN ISLAND, OVER THE
LEIZHOU PENINSULA, AROUND TAU 48, FOLLOWED BY A SECONDARY LANDFALL
NEAR THE CHINA-VIETNAM BORDER BETWEEN TAU 48 AND 72. AFTERWARD, THE
SYSTEM IS EXPECTED TO WEAKEN STEADILY DUE TO INCREASING LAND
INTERACTION AND DISSIPATE BEFORE THE END OF THE FORECAST PERIOD.

MODEL DISCUSSION: NUMERICAL GUIDANCE REMAINS IN GENERAL CONSENSUS
REGARDING THE SYNOPTIC STEERING PATTERN AND OVERALL TRACK SCENARIO
THROUGHOUT THE FORECAST PERIOD. TRACK SPREAD AMONG CONSENSUS
MEMBERS IS APPROXIMATELY 55 NM PRIOR TO THE FINAL LANDFALL. THE
JTWC OFFICIAL TRACK FORECAST CLOSELY ALIGNS WITH THE MULTI-MODEL
CONSENSUS AND IS POSITIONED ON THE NORTHERN EDGE OF THE GUIDANCE
ENVELOPE. IN TERMS OF INTENSITY, THE FORECAST IS ASSESSED WITH
MEDIUM CONFIDENCE DUE TO THE IMPACT OF LAND INTERACTION AND
RE-EMERGENCE TIMING OVER OPEN WATER WITHIN THE NEXT FEW HOURS.
FAVORABLE THERMODYNAMIC CONDITIONS - INCLUDING HIGH SST, ROBUST
UPPER-LEVEL OUTFLOW, AND LOW VERTICAL WIND SHEAR - WILL PERSIST
THROUGHOUT THE MAJORITY OF THE FORECAST TRACK OVER THE SOUTH CHINA
SEA. VWS IS EXPECTED TO SLIGHTLY INCREASE, SHORTLY AFTER TAU 36,
SLOWING DOWN DEVELOPMENT. THE POTENTIAL FOR SHORT-TERM 
INTENSIFICATION IS HIGH, AS MULTIPLE RAPID INTENSIFICATION (RI) AIDS 
HAVE BEEN TRIGGERED. OVERALL, FAVORABLE CONDITIONS WILL ALLOW THE 
SYSTEM TO REACH PEAK INTENSITY AROUND TAU 36. ALL OF THE 
DETERMINISTIC INTENSITY MODELS REMAIN UNDER 90 KTS PEAK INTENSITY AND 
INDICATE RAPID WEAKENING FOLLOWING THE LANDFALL, INCREASING 
CONFIDENCE FOR THE LATER STAGES OF THE FORECAST TO HIGH.

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