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JTWC SUMMARY: TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 30 NM NORTHWEST OF PAGO PAGO, HAS TRACKED SOUTHEASTWARD AT 07 KNOTSOVER THE PAST SIX HOURS. LATEST IMAGERY DEPICTS A SIGNIFICANTLY WEAKENED SYSTEM, WITH THE LOW LEVEL CIRCULATION CENTER (LLCC) POSSIBLY BECOMING SEPARATED FROM A SIGNIFICANTLY WEAKER CONVECTIVE SIGNATURE. SURFACE OBSERVATIONS FROM PAGO PAGO INDICATE SURFACE WINDS HAVE BEEN FROM THE EAST OVER THE PAST FOUR HOURS, WHICH PROVIDES FURTHER SUPPORT TO THE RELOCATED INITIAL POSITION, THOUGH THE OVERALL CONFIDENCE IN THE POSITION IS LOW. THE CURRENT INTENSITY IS ASSESSED AT 70 KNOTS. TC AMOS HAS CONTINUED TO TRACK TOWARDS THE SOUTHEAST UNDER THE STEERING INFLUENCE OF A NEAR-EQUATORIAL RIDGE (NER), BUT ACTUALLY SLOWED SINCE 1200Z VICE SPED UP AS DISCUSSED IN THE PREVIOUS WARNING DISCUSSION. THE AFOREMENTIONED NER WILL BUILD IN ON THE EASTERN SIDE OF THE SYSTEM, SLOWING AND SHIFTING THE TRACK TO A MORE SOUTHERLY DIRECTION BY TAU 36. AFTER TAU 72, THE SYSTEM BECOMES EXTREMELY WEAK AS IT IS SHEARED APART AND THE PRIMARY STEERING SHIFTS TO THE LOW LEVEL SUBTROPICAL RIDGE (STR) FAR TO THE SOUTHWEST, RESULTING IN A GENTLE TURN TOWARDS THE NORTHEAST THROUGH THE REMAINDER OF THE FORECAST PERIOD. THIS IS BEING OFFSET HOWEVER, BY MODERATE VERTICAL WIND SHEAR (VWS) OF 20-25 KNOTS FROM THE WEST. AS TC AMOS CONTINUES TRACKING SOUTH-SOUTHEASTWARD, VWS WILL CONTINUE TO INCREASE LEADING TO FURTHER WEAKENING UNTIL DISSIPATING OVER WATER BY TAU 120. NUMERICAL MODELS ARE GENERALLY IN GOOD AGREEMENT THROUGH TAU 36 AND THE TRACK FORECAST LIES NEAR THE MULTI-MODEL CONSENSUS AND THE ECMWF TRACK FORECAST. THERE IS INCREASING UNCERTAINTY REGARDING TRACK AND INTENSITY BEYOND TAU 36, PROVIDING LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 240000Z IS 26 FEET. NEXT WARNINGS AT 240900Z, 241500Z, 242100Z AND 250300Z.