Typhoon 14W(MUIFA)still strong slowly nearing China//15W(MERBOK) to peak at CAT2 //TD 16W:marked intensification after 48h//1303utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON 14W(MUIFA),15W(MERBOK) AND 16W.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS DEEP CONVECTIVE BANDING PERSISTING AROUND AN APPROXIMATELY 30 NM DIAMETER RAGGED EYE. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE EYE FEATURE EVIDENT IN MULTISPECTRAL IMAGERY AND RADAR IMAGERY AND FIX DATA FROM JAPAN. THE INITIAL INTENSITY OF 90 KTS IS ASSESSED WITH MEDIUM CONFIDENCE, CONSERVATIVELY SET AT THE LOWER END OF SUBJECTIVE DVORAK AND AUTOMATED INTENSITY ESTIMATES RANGING FROM 90 TO 102 KNOTS.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TY 14W HAS BRIEFLY TRACKED A BIT TO THE EAST OF DUE NORTHWARD OVER THE PAST SIX HOURS. DESPITE THE EASTWARD COMPONENT TO RECENT MOTION, TY 14W IS EXPECTED TO VEER GENERALLY NORTH-NORTHWESTWARD FOR THE DURATION OF THE FORECAST PERIOD UNDER THE INCREASINGLY PRONOUNCED STEERING INFLUENCE OF THE STR POSITIONED TO THE NORTHEAST. THE SYSTEM IS EXPECTED TO MAINTAIN INTENSITY OR PERHAPS CONTINUE INTENSIFYING SLIGHTLY UNDER THE FAVORABLE INFLUENCES OF STRONG POLEWARD OUTFLOW AND LOW VERTICAL WIND SHEAR, WITH DECREASING ALONG-TRACK OCEAN HEAT CONTENT AS A POTENTIAL LIMITING FACTOR. AS 14W PROGRESSES ALONG ITS TRACK, DECREASING SEA SURFACE TEMPERATURES WILL INDUCE WEAKENING PRIOR TO LANDFALL. HOWEVER, THE SYSTEM IS STILL EXPECTED TO MAKE LANDFALL JUST SOUTH OF SHANGHAI AT OR NEAR MINIMAL TYPHOON INTENSITY AROUND TAU 36. STEADY WEAKENING WILL OCCUR AS THE SYSTEM MOVES INLAND, WITH DISSIPATION ANTICIPATED BY TAU 96.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS DEEPENING CONVECTIVE BANDING WRAPPING TIGHTLY AROUND A CONSOLIDATING LOW-LEVEL CIRCULATION CENTER. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON RECENT SATELLITE FIXES FROM PGTW, KNES AND RJTD, AS WELL AS 122012Z SSMIS 37 GHZ IMAGERY SHOWING AN UPSTREAM LOW-LEVEL EYE FEATURE. THE INITIAL INTENSITY OF 55 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON RECENT AUTOMATED AND SUBJECTIVE DVORAK INTENSITY ESTIMATES AS WELL AS RECENT ASCAT PASSES COVERING THE EASTERN PORTION OF THE CIRCULATION.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TS 15W WILL TRACK POLEWARD THROUGH TAU 36 AND TURN TOWARD THE NORTH-NORTHEAST FOR THE REMAINDER OF THE FORECAST PERIOD FOLLOWING THE FLOW ASSOCIATED WITH SUBTROPICAL RIDGING TO THE EAST AND NORTHEAST. STEADY INTENSIFICATION WILL LIKELY CONTINUE FOR THE NEXT 36 HOURS AS THE SYSTEM PASSES OVER WARM WATER, VERTICAL WIND SHEAR REMAINS LOW AND THE OUTFLOW PATTERN IS GENERALLY SUPPORTIVE. THEREAFTER, COOLING ALONG-TRACK SEA SURFACE TEMPERATURES AND INCREASING VERTICAL WIND ASSOCIATED WITH A MID-LATITUDE TROUGH APPROACHING FROM THE NORTHWEST WILL INDUCE WEAKENING. BETWEEN TAU 48 AND TAU 72, TS 15W WILL BECOME EMBEDDED IN THE AFOREMENTIONED TROUGH AND COMPLETE EXTRATROPICAL TRANSITION. FAVORABLE BAROCLINIC INTERACTION BETWEEN THE SYSTEM AND THE TROUGH WILL ENABLE 15W TO TRANSITION INTO A VERY STRONG EXTRATROPICAL LOW BY TAU 72.

MODEL DISCUSSION: NUMERICAL MODEL TRACK FORECASTS REMAIN IN EXCELLENT AGREEMENT THROUGH THE ENTIRETY OF THE FORECAST PERIOD. INTENSITY GUIDANCE IS IN FAIR AGREEMENT AS WELL, PARTICULARLY REGARDING THE OVERALL TREND, TIMING OF PEAK INTENSITY AND HIGH POST-EXTRATROPICAL TRANSITION INTENSITY.