WDPN31 PGTW 302100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 20W (MINDULLE) WARNING NR 034//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 30.4N 139.3E
   INITIAL INTENSITY: 80 KTS
   GEOGRAPHIC REFERENCE: 295 NM SOUTH OF YOKOSUKA, JAPAN
   MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 15 KTS
   SIGNIFICANT WAVE HEIGHT: 41 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A
SYMMETRICAL SYSTEM WITH A RAGGED, BUT DEFINED, 30-NM EYE. FEEDER
BANDS ARE UNRAVELING AND THE CONVECTIVE TOPS HAVE CONTINUED TO
WARM. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON
THE EYE FEATURE IN THE EIR LOOP. THE INITIAL INTENSITY OF 80 KNOTS
IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE OVERALL ASSESSMENT
OF AGENCY AND AUTOMATED DVORAK ESTIMATE VALUES. THE ENVIRONMENT IS
MARGINALLY UNFAVORABLE, DESPITE LOW VWS AND MODERATE POLEWARD 
OUTFLOW, TY 20W HAS BEGUN TRACKING OVER A REGION OF LOW OCEAN HEAT 
CONTENT WITH COLD DRY AIR BEGINNING TO WRAP IN FROM THE NORTHWEST.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA 

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE TO THE SOUTHEAST

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T4.5 - 77 KTS
   RJTD: T5.0 - 90 KTS
   KNES: T4.5 - 77 KTS
   CIMSS ADT: 82 KTS AT 301820Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY
UNFAVORABLE
   VWS: 15-20 KTS
   SST: 27-28 CELSIUS
   OUTFLOW: STRONG POLEWARD
   OTHER FACTORS: COLD DRY AIR ENTRAINMENT

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   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: TYPHOON MINDULLE WILL CONTINUE ON ITS CURRENT
TRACK FOR THE REMAINDER OF THE FORECAST. THE ENVIRONMENT WILL
SLOWLY DEGRADE WITH CONTINUED COLD DRY AIR ENTRAINMENT AND
DECREASING SEA SURFACE TEMPERATURES AS THE CYCLONE CONTINUES
POLEWARD. CONCURRENTLY, BY TAU 36, IT WILL BEGIN EXTRA-TROPICAL
TRANSITION (ETT) AND BY TAU 48 WILL TRANSFORM INTO A 48-KT COLD
CORE LOW WITH AN EXPANSIVE WIND FIELD AS IT PASSES TO THE EAST OF
HOKKAIDO. 


MODEL DISCUSSION: NUMERICAL MODELS ARE IN VERY TIGHT AGREEMENT,
LENDING HIGH CONFIDENCE TO THE JTWC TRACK FORECAST. HOWEVER, GIVEN
THE VARIABILITY ASSOCIATED WITH ETT, THERE IS ONLY MEDIUM
CONFIDENCE IN THE INTENSITY FORECAST. 

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