Super Typhoon 02W(MAWAR) current intensity may be under-estimated, erratic track possible after 72hours//2709UTC

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON STY 02W(MAWAR).

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES A SYMMETRIC SYSTEM OF TIGHTLY WRAPPING DEEP CONVECTIVE BANDS FEEDING INTO A LARGE (30NM) EYE. A RECENT 270421Z AMSR2 89GHZ MICROWAVE IMAGE REVEALS A LARGE AND NEARLY COMPLETE EYE WALL WITH NUMEROUS FRAGMENTED DEEP CONVECTIVE BANDS WRAPPING INTO THE SYSTEM FROM THE SOUTH AND WEST. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE 30NM EYE IN BOTH MSI AND AMSR2 MICROWAVE IMAGERY. THE INITIAL INTENSITY IS PLACED WITH MEDIUM CONFIDENCE BASED ON DVORAK INTENSITY ESTIMATES WHICH INDICATE 127KTS AND CIMMS ADT/AiDT INDICATING 115-120KTS WHILE CIMMS D-MINT AND D-PRINT REMAIN HIGHER AT 151KTS AND 137KTS RESPECTIVELY. HAVING LIKELY CONCLUDED AN EYE WALL REPLACEMENT CYCLE (ERC) WITHIN THE PAST 6 HOURS, THE INTENSITY OF THE SYSTEM MAY HAVE DROPPED TEMPORARILY AS THE NEW EYE WALL FORMS AND SETTLES IN, SO A RUSH TO DRAMATICALLY WEAKEN THE SYSTEM MAY NOT BE THE CORRECT PATH.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: STY 02W (MAWAR) IS FORECASTED TO CONTINUE TRACKING WEST-NORTHWESTWARD UNDER THE STEERING INFLUENCE OF THE STR TO THE NORTHEAST. OVER THE COMING HOURS, STY 02W IS LIKELY TO CONTINUE ON THIS WEAKENING TREND AND FINALLY WEAKEN BELOW STY STRENGTH BY TAU 24 AS IT MOVES INTO A LESS FAVORABLE ENVIRONMENT CHARACTERIZED BY COOLING SSTS AND DRY AIR ENTRAINMENT FROM THE WEST. BY TAU 48, AS 02W APPROACHES THE LUZON STRAIT, IT WILL ENTER A COMPLEX AND COMPETING STEERING ENVIRONMENT ENTRENCHED BETWEEN A STR TO THE NORTHWEST OVER SOUTHEAST CHINA AND THE OTHER STR TO THE NORTHEAST. AFTER TAU 48, WEAK OUTFLOW, COOLER SSTS AND DRY-AIR ENTRAINMENT FROM CHINA, WILL CONSPIRE TO FURTHER WEAKEN THE SYSTEM AS IT TRANSITIONS INTO A GENERALLY NORTHWARD HEADING. AS STY 02W EVENTUALLY STEADIES UP ON A NORTH-NORTHEASTWARD TRACK IN AN INCREASINGLY HARSH ENVIRONMENT, INTENSITIES WILL FALL TO AROUND 60KTS BY TAU 120 AND CONTINUE TO FALL THEREAFTER.

MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGH TAU 72 WITH A 110NM CROSS-TRACK SPREAD IN SOLUTIONS, LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK DURING THIS TIME. AT THE APPROACH TO TAU 72 AND BEYOND, THE COMPETING STEERING PATTERN INCREASES THE OVERALL UNCERTAINTY IN THE EXTENDED FORECAST TRACK WITH A MARKED DECREASE IN TRACK SPEEDS AND POSSIBLE QUASI-STATIONARY MOTION EAST OF TAIWAN. COAMPS-TC (NVGM VERSION), HWRF AND AFUM THROW CAUTION TO THE WIND AND PLOW STRAIGHT INTO THE RIDGE TO THE WEST AND EVENTUALLY INTO TAIWAN. THE BULK OF THE GUIDANCE HOWEVER, STAYS CLOSE TO THE JTWC FORECAST TRACK FOLLOWING TAU 72. AS THE MODELS CONTINUE TO STRUGGLE TO RESOLVE THE TIMING OF THE TURN, THE POTENTIAL FOR ERRATIC TRACK MOTION IS LIKELY TO OCCUR IN THE LATER TAUS, LENDING OVERALL HIGH CONFIDENCE IN THE JTWC TRACK AND INTENSITY GUIDANCE OUT TO TAU 72, BECOMING MEDIUM THEREAFTER.