WDPN31 PGTW 060900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 02W (PENHA) WARNING 
NR 010//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 9.9N 123.6E
   INITIAL INTENSITY: 30 KTS
   GEOGRAPHIC REFERENCE: 321 NM SOUTH-SOUTHEAST OF MANILA,
PHILIPPINES
   MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 09 KTS
   SIGNIFICANT WAVE HEIGHT: 12 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
DEPRESSION (TD) 02W (PENHA) WITH AN INCREASINGLY DISORGANIZED
LOW-LEVEL CIRCULATION CENTER (LLCC), OBSCURED BY FLARING CONVECTION 
NEAR NEGROS AND PANAY. FRAGMENTED LOW-LEVEL CLOUD LINES HAVE BEEN
OBSERVED WRAPPING BENEATH THE PRIMARY CONVECTIVE STRUCTURES IN
CLOSE PROXIMITY TO THE LLCC OVER THE LAST FEW HOURS, HOWEVER,
PERSISTENT MODERATE VERTICAL WIND SHEAR (VWS) HAS BEGUN TILTING THE
VERTICAL STRUCTURE WESTWARD SINCE THE PREVIOUS WARNING. THE
ENVIRONMENT IS MARGINALLY UNFAVORABLE, WITH MODERATE VWS,
INTERMITTENT POCKETS OF COOLER SEA SURFACE TEMPERATURES NEAR 26 C,
AND SUPPORTIVE POLEWARD OUTFLOW ALOFT. THE INITIAL POSITION HAS BEEN 
PLACED WITH LOW CONFIDENCE BASED ON ANIMATED MSI IMAGERY. THE INITIAL
INTENSITY HAS BEEN ASSESSED WITH MEDIUM CONFIDENCE BASED ON
SUBJECTIVE AGENCY DVORAK ESTIMATES BETWEEN 25-35 KTS.

INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).

CURRENT STEERING MECHANISM: THE SOUTHWEST EXTENT OF A SUBTROPICAL
RIDGE (STR) CENTERED TO THE EAST-NORTHEAST

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.5 - 35 KTS
   RJTD: T1.5 - 25 KTS
   RCTP: T2.5 - 35 KTS
   KNES: T2.5 - 35 KTS
   CIMSS SATCON: 46 KTS AT 060512Z
   CIMSS ADT: 53 KTS AT 060530Z
   CIMSS AIDT: 44 KTS AT 060530Z
   CIMSS D-MINT: 44 KTS AT 060512Z
   CIMSS D-PRINT: 44 KTS AT 060710Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY
UNFAVORABLE
   VWS: 20-25 KTS
   SST: 27-28 CELSIUS
   OUTFLOW: MODERATE POLEWARD

ANALYSIS CONFIDENCE:
   INITIAL POSITION: LOW
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: NOT APPLICABLE

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TD 02W IS FORECASTED TO CONTINUE TRACKING TO
THE NORTHWEST THROUGHOUT THE 24-HOUR PERIOD, ALONG THE SOUTHWESTERN
EXTENT OF THE STR POSITIONED TO THE EAST-NORTHWEST UNTIL
DISSIPATION OVER WATER. REGARDING INTENSITY, TD PENHA IS FORECASTED
TO CONTINUE GRADUALLY WEAKENING OVER THE NEXT 24 HOURS, DUE TO
SUSTAINED MODERATE VERTICAL WIND SHEAR ABOVE 15 KTS, PERSISTENT
COOLER SEA SURFACE TEMPERATURES NEAR 26 C WITHIN THE NORTHERN SULU
SEA, AND INCREASING DRY-AIR ENTRAINMENT FROM THE SOUTHEAST. IN
ADDITION, TD 02W WILL CONTINUE TO DECAY AS AN INCREASING NORTHEAST
SURGE INTO THE EAST CHINA SEA AND SULU SEA SHALLOW THE SYSTEM NEAR
THE SURFACE, FILLING THE SURFACE CLOSED LOW INTO AN OPEN TROUGH BY
TAU 24. 

MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE AND ARTIFICIAL
INTELLIGENCE (AI) MODEL GUIDANCE REMAINS IN FAIRLY GOOD AGREEMENT
THROUGH THE FORECAST PERIOD, WITH AN EXPECTED NORTHWEST TRACK AND A
56 NM CROSS-TRACK SPREAD. THE PROBABILISTIC ECMWF SOLUTION REMAINS
AS THE ONLY OUTLIER, WITH A NORTHWARD TRACK AT TAU 12 UNTIL
DISSIPATION. THE JTWC TRACK FORECAST HAS BEEN PLACED WITH MEDIUM
CONFIDENCE, AND ALIGNED CLOSELY TO THE JTWC MULTI-MODEL CONSENSUS.
REGARDING INTENSITY, ALL JTWC INTENSITY CONSENSUS MEMBERS ILLUSTRATE
STEADY TO WEAKENING INTENSITIES OVER THE NEXT 24 HOURS, WITH GFS
BEING THE MOST AGGRESSIVE DURING THE TERMINAL WEAKENING PHASE. THE
JTWC INTENSITY FORECAST HAS BEEN PLACED CLOSE TO THE MULTI-MODEL
INTENSITY CONSENSUS UNTIL TAU 12, THEN NEAR HAFS-A AND GFS
THEREAFTER UNTIL DISSIPATION DUE TO THE INCREASINGLY HOSTILE
ENVIRONMENT IN THE SULU SEA, LENDING MEDIUM CONFIDENCE TO THE 
INTENSITY FORECAST.

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