WTXS31 PGTW 032100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 014// RMKS/ 1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 014 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 031800Z --- NEAR 23.8S 114.8E MOVEMENT PAST SIX HOURS - 090 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY A COMBINATION OF SATELLITE, RADAR AND SYNOPTIC DATA PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY REPEAT POSIT: 23.8S 114.8E --- FORECASTS: 12 HRS, VALID AT: 040600Z --- 24.1S 114.7E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 24 HR POSIT: 240 DEG/ 04 KTS --- 24 HRS, VALID AT: 041800Z --- 24.5S 113.9E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 36 HR POSIT: 215 DEG/ 04 KTS --- 36 HRS, VALID AT: 050600Z --- 25.2S 113.4E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 000 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 190 DEG/ 06 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 051800Z --- 26.3S 113.2E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 020 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 170 DEG/ 07 KTS --- 72 HRS, VALID AT: 061800Z --- 29.2S 113.8E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 032100Z POSITION NEAR 23.9S 114.8E. 03FEB21. TROPICAL CYCLONE 18S (EIGHTEEN), LOCATED APPROXIMATELY 98 NM SOUTH-SOUTHEAST OF LEARMONTH, AUSTRALIA, HAS TRACKED EASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS WELL ORGANIZED SYSTEM WITH A VERY COMPACT CORE OF DEEP CONVECTION AND LOW LEVEL BANDS WRAPPING INTO AN OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC). A COMBINATION OF ANALYSIS OF NEARBY SURFACE WIND OBSERVATIONS AND ANMIATED RADAR IMAGERY FROM LEARMONTH LENT HIGH CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 30 KNOTS WITH FAIR CONFIDENCE BASED PRIMARILY ON EXTRAPOLATION OF SURFACE OBSERVATION AND AN UNOFFICIAL (OVERLAND) DVORAK INTENSITY ESTIMATE OF T2.0 FROM PGTW. TC 18S IS CURRENTLY IN A WEAK STEERING ENVIRONMENT AND GENERALLY REMAINS QUASI-STATIONARY OVER THE PREVIOUS 6-12 HOURS. WHILE THE CENTER REMAINS OVERLAND, THE OVERALL ENVIRONMENT IS GENERALLY FAVORABLE, WITH LOW (10-15 KT) VWS, AND ROBUST POLEWARD OUTFLOW, THOUGH THE ATMOSPHERE HAS DRIED SOMEWHAT OVER THE PAST FEW HOURS AS INDICATED BY THE TOTAL PRECIPITABLE WATER (TPW) LOOP. THE DEEP STR LOCATED TO THE NORTHEAST SHOULD START TO ASSERT ITS INFLUENCE OVER THE NEXT 12 HOURS, PUSHING TC 18S TOWARDS THE SOUTHWEST, EMERGEING OVER WATER BETWEEN TAU 24 AND TAU 36. ONCE THE SYSTEM MOVES OVER THE WARM (26-27C) WATERS WEST OF AUSTRALIA, IT WILL HAVE A SHORT WINDOW WHERE VWS REMAINS IN THE LOW TO MODERATE RANGE AND IS OFFSET BY STRONG POLEWARD OUTFLOW AND SHOULD PEAK AT 35 KTS BY TAU 36. THEREAFTER, SSTS RAPIDLY DECREASE TO LESS THAN 25C WHILE VWS INCREASES DRAMATICALLY AHEAD OF AN APPROACHING MID-LATITUDE TROUGH, SERVING TO DISSIPATE THE SYSTEM NO LATER THAN TAU 72. NUMERICAL MODEL GUIDANCE IS IN POOR AGREEMENT DUE TO THE HIGH UNCERTAINTY ASSOCIATED WITH THE TIMING AND STRENGTH OF THE NEAR-TERM TURN SOUTHWESTWARD, WHICH LEADS TO A BROAD SPREAD IN MODEL SOLUTIONS IN THE LONGER-RANGE FORECAST. THE JTWC FORECAST IS PLACED NEAR THE MULTI-MODEL CONSENSUS WITH LOW CONFIDENCE. NEXT WARNINGS AT 040300Z, 040900Z, 041500Z AND 042100Z.// NNNN