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![]() Tropical Cyclone 201202 Southern Hemisphere Summary |
WTXS21 PGTW 20111206 03:00z MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/TROPICAL CYCLONE FORMATION ALERT// RMKS/ 1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 120 NM EITHER SIDE OF A LINE FROM 16.9S 69.9E TO 17.5S 65.5E WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA ARE ESTIMATED TO BE 28 TO 32 KNOTS. METSAT IM- AGERY AT 060000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 17.0S 69.6E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 06 KNOTS. 2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 16.4S 69.9E, IS NOW LOCATED NEAR 17.0S 69.6E, APPROXIMATELY 830 NM EAST- NORTHEAST OF LA REUNION. ANIMATED INFRARED SATELLITE IMAGERY SHOWS CONVECTION DEEPENING AND CONSOLIDATING OVER THE LOW LEVEL CIRCULATION CENTER (LLCC). AGENCY DVORAK ESTIMATES HAVE RISEN TO BETWEEN 25 AND 35 KNOTS, AND A 060055Z SSMIS IMAGES REVEALS THICK CURVED CONVECTIVE BANDING ORGANIZING AROUND THE LLCC. THE MOST RECENT UPPER LEVEL ANALYSIS DEPICTS THE LLCC DIRECTLY UNDERNEATH THE SUBTROPICAL RIDGE AXIS IN A REGION OF MINIMAL VERTICAL WIND SHEAR. 27 DEGREE SEA SURFACE TEMPERATURES ARE FAVORABLE FOR FURTHER DEVELOPMENT. THE LATEST MODEL GUIDANCE, ALTHOUGH SPARSE, INDICATES WESTWARD MOVEMENT FOR THE LLCC, WHICH WILL KEEP THE SYSTEM OVER WARM WATERS. ANIMATED WATER VAPOR IMAGERY REVEALS SOME IMPINGEMENT ON OUTFLOW OVER THE WESTERN SEMICIRCLE BUT GOOD OUTFLOW ELSEWHERE, INCLUDING A DEVELOPING POLEWARD CHANNEL OVER THE SOUTHWEST QUADRANT. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO HIGH. 3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 070300Z. ========================================================================= WTXS32 PGTW 20111206 09:00z MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/TROPICAL CYCLONE 02S (TWO) WARNING NR 001// REF/A/MSG/NAVMARFCSTCEN PEARL HARBOR HI/060251ZDEC2011// AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.// RMKS/ 1. TROPICAL CYCLONE 02S (TWO) WARNING NR 001 02 ACTIVE TROPICAL CYCLONES IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 060600Z --- NEAR 17.2S 69.1E MOVEMENT PAST SIX HOURS - 230 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY REPEAT POSIT: 17.2S 69.1E --- FORECASTS: 12 HRS, VALID AT: 061800Z --- 17.6S 67.7E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 24 HR POSIT: 255 DEG/ 07 KTS --- 24 HRS, VALID AT: 070600Z --- 17.9S 66.3E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 260 DEG/ 07 KTS --- 36 HRS, VALID AT: 071800Z --- 18.1S 64.9E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 270 DEG/ 07 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 080600Z --- 18.1S 63.5E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER VECTOR TO 72 HR POSIT: 270 DEG/ 04 KTS --- 72 HRS, VALID AT: 090600Z --- 18.1S 62.0E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 060900Z POSITION NEAR 17.3S 68.7E. TROPICAL CYCLONE (TC) 02S, LOCATED APPROXIMATELY 685 NM EAST- NORTHEAST OF PORT LOUIS, HAS TRACKED SOUTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS TIGHTLY-CURVED LOW-LEVEL BANDING WRAPPING INTO A WELL- DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH LIMITED DEEP CONVECTION OVER THE EASTERN SEMI-CIRCLE. ANIMATED INFRARED SATELLITE IMAGERY INDICATES THAT DEEP CONVECTIVE ORGANIZATION HAS WEAKENED SINCE AN IMPRESSIVE, CONSOLIDATED SIGNATURE NEAR 06/0200Z (ALSO SEE THE 052325Z SSMI). HOWEVER, A 060410Z ASCAT IMAGE (25-KM) SHOWS 30- 35 KNOT WINDS OVER THE SOUTHERN SEMI-CIRCLE SUPPORTING THE CURRENT INTENSITY ASSESSMENT OF 35 KNOTS. DVORAK INTENSITY ESTIMATES ALSO RANGE FROM 30-35 KNOTS. TC 02S IS FORECAST TO TRACK GENERALLY WESTWARD UNDER THE STEERING INFLUENCE OF A LOW-LEVEL SUBTROPICAL RIDGE (STR) SITUATED TO THE SOUTH. MODEL GUIDANCE IS LIMITED BUT IS IN GOOD AGREEMENT THROUGH THE FORECAST PERIOD. TC 02S IS EXPECTED TO INTENSIFY SLIGHTLY BUT SHOULD WEAKEN AND DISSIPATE BY TAU 72 DUE TO INCREASING VERTICAL WIND SHEAR ASSOCIATED WITH STRONG WESTERLY FLOW. THIS WARNING SUPERSEDES AND CANCELS REF A, NAVMARFCSTCEN 060251Z DEC 11 TROPICAL CYCLONE FORMATION ALERT (WTXS21 PGTW 060300). MAXIMUM SIGNIFICANT WAVE HEIGHT AT 060600Z IS 11 FEET. NEXT WARNINGS AT 062100Z AND 070900Z. REFER TO TROPICAL CYCLONE 01S (ALENGA) WARNINGS (WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.// ========================================================================= WTXS32 PGTW 20121206 21:00z MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/TROPICAL CYCLONE 02S (TWO) WARNING NR 002// RMKS/ 1. TROPICAL CYCLONE 02S (TWO) WARNING NR 002 02 ACTIVE TROPICAL CYCLONES IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 061800Z --- NEAR 17.5S 68.4E MOVEMENT PAST SIX HOURS - 215 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY REPEAT POSIT: 17.5S 68.4E --- FORECASTS: 12 HRS, VALID AT: 070600Z --- 17.9S 67.5E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 24 HR POSIT: 265 DEG/ 05 KTS --- 24 HRS, VALID AT: 071800Z --- 18.0S 66.5E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 36 HR POSIT: 265 DEG/ 05 KTS --- 36 HRS, VALID AT: 080600Z --- 18.1S 65.5E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 48 HR POSIT: 270 DEG/ 05 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 081800Z --- 18.1S 64.4E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER VECTOR TO 72 HR POSIT: 285 DEG/ 05 KTS --- 72 HRS, VALID AT: 091800Z --- 17.6S 62.4E MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 062100Z POSITION NEAR 17.6S 68.2E. TROPICAL CYCLONE (TC) 02S, LOCATED APPROXIMATELY 760 NM EAST- NORTHEAST OF LA REUNION HAS TRACKED SOUTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY OVER THE PAST SIX HOURS SHOWS CONVECTIVE CLOUD TOPS COOLING AND STRETCHING. THE SYSTEM IS EXHIBITING STRONG DIURNAL CYCLING AND STRUGGLING TO INTENSIFY. A 061643Z ASCAT IMAGE DOES REVEAL A TIGHTLY ORGANIZED LOW LEVEL CIRCULATION CENTER, HOWEVER, AS WELL AS A SIGNIFICANT BAND OF 30-35 KNOT WINDS OVER THE SOUTHWESTERN QUADRANT. ALTHOUGH AGENCY DVORAK ASSESSMENTS HAVE FALLEN TO 25-35 KNOTS, THE CURRENT INTENSITY REMAINS 35 KNOTS BASED ON THE ASCAT IMAGE. ANIMATED WATER VAPOR IMAGERY INDICATES GOOD RADIAL OUTFLOW. THE 061200Z PGTW UPPER LEVEL STREAMLINE ANALYSIS DEPICTS TC 02S JUST POLEWARD OF THE SUBTROPICAL RIDGE AXIS BENEATH A REGION OF DIFFLUENT FLOW AND LOW VERTICAL WIND SHEAR. ALONG-TRACK SEA SURFACE TEMPERATURES OF 27 DEGREES ARE MINIMALLY SUPPORTIVE OF DEVELOPMENT. THE SLOW AND ERRATIC DEVELOPMENT OF TC 02S, WHICH ORIGINATED AS A DISTURBANCE NINE DAYS AGO, INDICATE THAT THE SYSTEM WILL MAINTAIN A RELATIVELY FLAT INTENSITY TREND OVER THE NEXT 48 HOURS AS IT TRACKS WESTWARD. NEAR TAU 48, SURGING UPPER LEVEL WESTERLIES SURING OVER MADAGASCAR AND INTO THE SOUTHWEST INDIAN OCEAN WILL INCREASE VERTICAL WIND SHEAR AND THE SYSTEM WILL DISSIPATE OVER WATER. MODEL GUIDANCE IS IN GOOD AGREEMENT REGARDING BOTH TRACK AND INTENSITY. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 061800Z IS 11 FEET. NEXT WARNINGS AT 070900Z AND 072100Z. REFER TO TROPICAL CYCLONE 01S (ALENGA)WARNINGS (WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.// ========================================================================= WTXS32 PGTW 20111207 09:00z MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/TROPICAL CYCLONE 02S (TWO) WARNING NR 003// RMKS/ 1. TROPICAL CYCLONE 02S (TWO) WARNING NR 003 02 ACTIVE TROPICAL CYCLONES IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 070600Z --- NEAR 16.3S 67.3E MOVEMENT PAST SIX HOURS - 270 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER REPEAT POSIT: 16.3S 67.3E --- FORECASTS: 12 HRS, VALID AT: 071800Z --- 16.4S 66.6E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER VECTOR TO 24 HR POSIT: 280 DEG/ 03 KTS --- 24 HRS, VALID AT: 080600Z --- 16.3S 66.0E MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 070900Z POSITION NEAR 16.3S 67.1E. TROPICAL CYCLONE (TC) 02S, LOCATED APPROXIMATELY 605 NM SOUTH- SOUTHWEST OF DIEGO GARCIA HAS TRACKED WESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY REVEALS A FULLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH MINIMAL CONVECTION TO THE SOUTH. A 070119Z CORIOLIS 37GHZ MICROWAVE IMAGE SHOWS SHALLOW FRAGMENTED CONVECTION AROUND THE LLCC. THE INITIAL INTENSITY IS BASED ON THE PGTW DVORAK ESTIMATE OF 25 TO 30 KNOTS AND A 070117Z WINDSAT PASS DEPICTING 25-30 KNOT WINDS ALONG THE SOUTHERN PERIPHERY OF THE LLCC. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS LOCATED DIRECTLY BENEATH THE SUBTROPICAL RIDGE AXIS, IN AN AREA OF LOW (05-10 KNOT) VERTICAL WIND SHEAR. TC 02S IS CURRENTLY LOCATED WITHIN A WEAK STEERING ENVIRONMENT, PRIMARILY DRIVEN BY A WEAK LOW- TO MID-LEVEL STEERING RIDGE TO THE SOUTH OF THE SYSTEM. TC 02S SHOULD CONTINUE TO TRACK SLOWLY WESTWARD AND WEAKEN AS IT ENCOUNTERS INCREASED VERTICAL WIND SHEAR. MODEL GUIDANCE IS IN GOOD AGREEMENT REGARDING BOTH TRACK AND INTENSITY. THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WARNING CENTER (NAVMARFCSTCEN). THE SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 070600Z IS 12 FEET. REFER TO TROPICAL CYCLONE 01S (ALENGA) WARNINGS (WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.//
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Document: tropical_cyclone_201202.htm | Updated: 9 December 2011 |