WDIO31 PGTW 072100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 02B (TWO) WARNING NR 003// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 10.6N 89.9E INITIAL INTENSITY: 50 KTS GEOGRAPHIC REFERENCE: 575 NM SOUTHEAST OF VISAKHAPATNAM, INDIA MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 08 KTS SIGNIFICANT WAVE HEIGHT: 18 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A MEDIUM-SIZED SYSTEM WITH A SYMMETRICAL COLD DENSE OVERCAST (CDO) THAT IS OBSCURING THE LOW LEVEL CIRCULATION (LLC). FORMATIVE BANDS ARE WRAPPING IN FROM THE NORTH AND WESTERN PERIPHERIES. THE EIR LOOP ALSO SHOWS PRESSURE ALONG THE EASTERN SIDE, AN INDICATION OF MODERATE EASTERLY VERTICAL WIND SHEAR (VWS). DESPITE THE SHEAR, THE CDO APPEARS TO HAVE DEEPENED AND EXPANDED OVER THE LAST SIX HOURS. THE INITIAL POSITION AND INTENSITY ARE PLACED WITH HIGH CONFIDENCE BASED ON A 071537Z ASCAT DIRECT PASS. OVERALL ASSESSMENT OF AGENCY AND AUTOMATED DVORAK ESTIMATES ALSO SUPPORT THE INITIAL INTENSITY. INITIAL WIND RADII BASIS: SCATTEROMETER DATA. CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE NORTHEAST AND EAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.0 - 45 KTS DEMS: T2.0 - 30 KTS CIMSS SATCON: 58 KTS AT 071313Z CIMSS ADT: 55 KTS AT 071515Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 15-20 KTS SST: 30-31 CELSIUS OUTFLOW: STRONG WESTWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 02B IS EXPECTED TO CONTINUE TRACKING NORTHWESTWARD ALONG THE PERIPHERY OF THE STR THROUGH TAU 36. AFTERWARD, IT WILL TURN MORE NORTHWARD THEN NORTHEASTWARD AS IT ROUNDS THE STR AXIS AS THE STR RECEDES IN RESPONSE TO AN APPROACHING MID-LATITUDE SHORTWAVE. THE FAVORABLE CONDITIONS WILL CARRY THROUGH TAU 48 AND FUEL A STEADY INTENSIFICATION TO PEAK OF 70KTS. THE SYSTEM WILL WEAKEN STEADILY DUE TO INCREASING VWS ASSOCIATED WITH THE PREVAILING WESTERLIES AND COOL DRY AIR FROM THE NORTH STREAMS INTO THE LLC. BY TAU 120, TC 02B WILL BE REDUCED TO 40KTS. MODEL DISCUSSION: THE MAJORITY OF THE NUMERICAL MODELS ARE IN GOOD AGREEMENT WITH THE FORECAST TRACK WITH THE SOLE EXCEPTION OF NAVGEM WHICH CONTINUES TO TRACK THE VORTEX WEST-NORTHWESTWARD INTO SOUTHERN INDIA, A SIGNIFICANT DEVIATION OF OVER 300NM AT TAU 72 FROM THE FORECAST TRACK. IN VIEW OF THIS, THERE IS MEDIUM CONFIDENCE IN THE JTWC FORECAST TRACK THAT IS LAID TO THE RIGHT OF CONSENSUS. THERE IS ALSO MEDIUM CONFIDENCE IN THE FORECAST INTENSITIES THAT ARE HELD SLIGHTLY HIGHER THAN CONSENSUS TOWARD THE MID PORTION OF THE FORECAST, INCLUDING PEAK INTENSITY. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN