WDIO31 PGTW 021500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03B (SHAHEEN-GULAB) WARNING NR 019// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 24.5N 60.7E INITIAL INTENSITY: 65 KTS GEOGRAPHIC REFERENCE: 268 NM NORTH-NORTHEAST OF MASIRAH ISLAND MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 09 KTS SIGNIFICANT WAVE HEIGHT: 24 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY OVER THE PAST SIX HOURS SHOWS THAT TC 03B HAS TRIED TO CLEAR OUT AN EYE, HOWEVER WHILE AN EYE FEATURE IS PRESENT, IT IS CLOUD-FILLED AND REMAINS SOMEWHAT RAGGED. A 020843Z AMSR2 MICROWAVE PASS SHOWED A BIT OF TILT IN THE VORTEX, WITH THE LOW LEVEL EYE DISPLACED ABOUT 7-NM TO THE EAST OF THE UPPER-LEVEL EYE FEATURE. THE INITIAL POSITION WAS ASSESSED WITH HIGH CONFIDENCE BASED ON THE SMALL EYE FEATURE EVIDENT IN THE 1200Z INFRARED BD-ENHANCEMENT AND EXTRAPOLATION OF THE AMSR2 36GHZ EYE FEATURE WITH HIGH CONFIDENCE. THE INITIAL INTENSITY IS INCREASED TO A CONSERVATIVE 65 KNOTS, IN LINE WITH THE PGTW FIX INTENSITY, THOUGH A BIT LOWER THAN THE ADT WOULD SUGGEST. ADDITIONALLY, THE AMSR2 WINDSPEED ESTIMATE ASSOCIATED WITH THE PREVIOUSLY MENTIONED MICROWAVE PASS INDICATED AN AREA OF 64 TO 68 KNOT WINDS CONFINED TO THE NORTHWEST SECTOR. INTERESTINGLY THE RAW ADT WAS SIGNIFICANTLY LOWER THAN THE FINAL-T EVEN THOUGH THE SYSTEM IS ON AN INTENSIFICATION TREND, AND THUS BRINGS SOME DOUBT INTO THE ADT INTENSITY ESTIMATE. THE ENVIRONMENT REMAINS FAVORABLE AND IS TRENDING BETTER. SHEAR IS LOWER THAN THE CIMSS AUTOMATED ANALYSIS WOULD SUGGEST, RUNNING ABOUT 10-12 KNOTS FROM THE EAST. SSTS ARE WARMING AS THE SYSTEM MOVES FURTHER WEST AS WELL, NOW APPROACHING 29C. LASTLY, THE UPPER-LEVEL ENVIRONMENT IS MARGINALLY FAVORABLE AT THE MOMENT. POLEWARD OUTFLOW AT THE 200MB LEVEL IS CONSTRAINED BY A 200MB ANTI-CYCLONE CENTERED DIRECTLY TO THE NORTH, AND THUS THE MAIN OUTFLOW IS CURRENTLY RESTRICTED TO A SINGLE EQUATORWARD CHANNEL. THERE IS A VERY SMALL POINT SOURCE DIRECTLY OVER TC 03B AND THAT IS PROVIDING SOME WEAK RADIAL OUTFLOW WHICH EXTENDS ONLY ABOUT 60-NM OUTWARD FROM THE CENTER AND A WEAK EXTENSION OUT TO THE WEST ALONG THE BASE OF THE 200MB RIDGE. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SOUTHERN PERIPHERY OF DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE NORTH. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.0 - 65 KTS DEMS: T3.5 - 55 KTS CIMSS SATCON: 69 KTS AT 020928Z CIMSS ADT: 77 KTS AT 021145Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 15-20 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE EQUATORWARD OTHER FACTORS: WEAK RADIAL OUTFLOW IN DIRECT VICINITY OF THE CENTER. 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. HOWEVER, PEAK INTENSITY HAS BEEN INCREASED TO 85 KNOTS. FORECAST DISCUSSION: TC 03B IS CURRENTLY TRACKING ALONG THE SOUTHWESTERN PERIPHERY OF THE STEERING RIDGE LOCATED TO THE EAST AND IS FORECAST TO CONTINUE TRACKING GENERALLY WEST-NORTHWESTWARD THROUGH TAU 24. THEREAFTER THE PRIMARY STEERING MECHANISM SWITCHES OVER TO THE EASTERN SIDE OF A BUILDING STR CENTERED TO THE WEST. ONCE THIS HANDOFF OCCURS, TC 03B WILL BEGIN A GRACEFUL TURN TO THE SOUTHWEST AFTER TAU 24 AND MAKE LANDFALL ALONG THE COAST OF OMAN, IN THE VICINITY OF SOHAR BETWEEN TAU 24 AND 36. PEAK INTENSITY IS INCREASED WITH THIS FORECAST TO 85 KNOTS PRIOR TO LANDFALL, WITH THE POSSIBILITY OF A HIGHER PEAK OCCURRING BEFORE IMPACT. THE ENVIRONMENT IS EXPECTED TO CONTINUE TO IMPROVE OVER THE NEXT 24 HOURS AS THE SYSTEM TRACKS WESTWARD. CONTRARY TO EXPECTATIONS, THE SYSTEM REMAINS ENSCONCED IN A POCKET OF MOIST AIR, AND MODELS SUGGEST NO SIGNIFICANT CHANGE TO THIS PATTERN THROUGH LANDFALL. SOME DRY AIR ENTRAINMENT CAN BE EXPECTED AS THE SYSTEM MOVES DEEPER INTO THE GULF OF OMAN, BUT THIS IS EXPECTED TO BE CONFINED TO THE LOWEST LEVELS OF THE ATMOSPHERE AND HAVE LITTLE OVERALL EFFECT. SSTS AND OHC LOOK TO INCREASE AS THE SYSTEM TRACKS WEST, AND ARE EXPECTED TO CRACK 30-31C AND 100 KJ PER CM2 BY TAU 24, PROVIDING AMPLE ENERGY FOR INTENSIFICATION. COLUMN MEAN SHEAR IS EXPECTED TO STEADILY DECREASE OVER THE NEXT 24 HOURS AS WELL, AS THE POINT SOURCE OVER TOP THE SYSTEM STRENGTHENS, ALLOWING THE SYSTEM TO BECOME MORE VERTICALLY STACKED. AT THE SAME TIME, THE 200MB ANTICYCLONE TO THE NORTH WILL MOVE OFF TO THE EAST, PUTTING TC 03B IN A FAVORABLE POSITION TO TAP INTO A WEAK POLEWARD OUTFLOW CHANNEL. THE COMBINATION OF ALL THESE FACTORS SUPPORT RELATIVELY RAPID INTENSIFICATION, THE SYSTEM INCREASING FROM 65 KNOTS TO 85 KNOTS IN 24 HOURS. MODEL DISCUSSION: TRACK GUIDANCE, WITH THE EXCEPTION OF NAVGEM, REMAINS IN GOOD AGREEMENT THROUGH THE FORECAST PERIOD, WITH A SPREAD OF 50 NM AT LANDFALL. NAVGEM IS THE PRIMARY OUTLIER, AND SHOWS THE SYSTEM STALLING BY TAU 24, THEN DRIFTING SOUTHWARD AND REMAINING OVER WATER THROUGH TAU 72 AS THE SYSTEM BECOMES ENCAPSULATED IN A WEAK STEERING ENVIRONMENT. THE JTWC TRACK LIES ON THE NORTH SIDE OF THE GUIDANCE ENVELOPE FOR THE DURATION OF THE FORECAST WITH HIGH CONFIDENCE. INTENSITY GUIDANCE REMAINS MIXED, WITH COTI INDICATING WEAKENING FROM TAU 00. THE REMAINDER OF THE GUIDANCE INDICATES INTENSIFICATION, BUT HWRF CONTINUES TO BE THE MOST AGGRESSIVE, SHOWING A PEAK OF 95 KNOTS AT TAU 24, WHILE SHIPS-N AND CTCX PEAK OUT AT 75 KNOTS. THE JTWC FORECAST IS ABOVE THE CONSENSUS MEAN BY ABOUT 10 KNOTS THROUGH THE FORECAST PERIOD, BUT REMAINS ABOUT 10 KNOTS BELOW THE HWRF PEAK WITH MEDIUM CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH INTENSITY 0 - 72 HR: MEDIUM// NNNN