WDPN31 PGTW 310300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 02W (MAWAR) WARNING NR 
045//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 21.5N 125.2E
   INITIAL INTENSITY: 60 KTS
   GEOGRAPHIC REFERENCE: 332 NM SOUTH-SOUTHWEST OF KADENA AB,
OKINAWA, JAPAN
   MOVEMENT PAST 6 HOURS: NORTH-NORTHEASTWARD AT 04 KTS
   SIGNIFICANT WAVE HEIGHT: 28 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS A SLOWLY
WEAKENING SYSTEM WITH PRONOUNCED CONVECTIVE DECAY ALONG THE
NORTHWEST QUADRANT. HOWEVER, THE CENTRAL DENSE OVERCAST CONTINUED
TO FLARE AROUND A DIMPLE FEATURE, PRESUMABLY ITS OBSCURED EYE. THE
INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE DIMPLE
IN THE MSI LOOP. THE INITIAL INTENSITY OF 60KTS IS PLACED WITH
HIGH CONFIDENCE BASED ON OVERALL ASSESSMENT OF AGENCY AND AUTOMATED
DVORAK ESTIMATES AND EXTRAPOLATED FROM A 302139Z SAR PASS AND
REFLECTS THE ONGOING WEAKENING TREND. ANALYSIS INDICATES AN
UNFAVORABLE ENVIRONMENT MOSTLY DUE TO THE 
INFLUX OF COOL DRY AIR FROM THE NORTHWEST AT THE LOW- TO MID-LEVELS
AND COOLING ALONG-TRACK SST EXACERBATED BY UPWELLING CAUSED BY THE
SLOW STORM MOTION.

INITIAL WIND RADII BASIS: SAR DATA.

CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO
THE EAST.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T3.5 - 55 KTS
   RJTD: T4.5 - 77 KTS
   KNES: T3.5 - 55 KTS
   CIMSS ADT: 43 KTS AT 302330Z
   UW-CIMSS AIDT: 45 KTS AT 302330Z
   UW-CIMSS D-PRINT: 66 KTS AT 310000Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE
   VWS: 0-5 KTS
   SST: 27-28 CELSIUS
   OUTFLOW: MODERATE RADIAL

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   INITIAL INTENSITY: HIGH
   INITIAL WIND RADII: HIGH

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TROPICAL STORM MAWAR HAS CRESTED THE STR AXIS AND
SHOULD BEGIN TO ACCELERATE AS IT RECURVES NORTHEASTWARD. THE
UNFAVORABLE ENVIRONMENT WILL BECOME WORSE AS VWS INCREASES AND SST 
DECREASES. HOWEVER, POLEWARD OUTFLOW WILL ALSO INCREASE AS THE SYSTEM 
APPROACHES THE PREVAILING WESTERLIES, RESULTING IN A TEMPERED 
WEAKENING IN THE SHORT TERM, THEN SUSTAINED INTENSITY IN THE EXTENDED 
PORTION OF THE FORECAST. CONCURRENTLY, BY TAU 72, THE SYSTEM WILL 
UNDERGO EXTRA-TROPICAL TRANSITION (ETT), AND BY TAU 120, TS 02W WILL 
BE TRANSFORM INTO A STRONG GALE-FORCE 45-KT COLD CORE LOW WITH AN 
EXPANDING WIND FIELD.

MODEL DISCUSSION: NUMERICAL MODELS REMAIN IN TIGHT AGREEMENT,
GRADUALLY AND EVENLY SPREADING OUT TO 100M BY TAU 72 THEN TO 250NM
BY TAU 120. ALSO, ALONG-TRACK SPEED DIFFERENCES BECOME MORE
PRONOUNCED AFTER TAU 72. IN VIEW OF THESE, AND GIVEN THE TYPICAL
UNCERTAINTIES OF ETT, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK
FORECAST UP TO TAU 72, THEN LOW CONFIDENCE AFTERWARD.

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