Tropical Cyclones [Index]

Tropical Cyclone 201401 Southern Hemisphere Summary

WTXS21 PGTW 20131025 23:00z
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 9.5S 69.4E TO 11.4S 63.4E
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 25 TO 30 KNOTS. METSAT
IMAGERY AT 252230Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 9.7S 68.7E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 06
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 9.5S 68.7E,
IS NOW LOCATED NEAR 9.7S 68.7E, APPROXIMATELY 265 NM WEST-SOUTHWEST
OF DIEGO GARCIA. ANIMATED INFRARED SATELLITE IMAGERY DEPICTS A
CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC) WITH CURVED
CONVECTIVE BANDING WRAPPING INTO THE LLCC. A 251729Z METOP-A 89 GHZ
IMAGE DEPICTS A PARTIALLY EXPOSED LLCC WITH A CURVED DEEP CONVECTIVE
BAND PERSISTING OVER THE SOUTHERN SEMI-CIRCLE. A 251728Z ASCAT IMAGE
INDICATES 25 TO 30 KNOT WINDS OVER THE SOUTHERN SEMI-CIRCLE WITH
20 TO 25 KNOT WINDS NOW PRESENT OVER THE NORTHERN SEMI-CIRCLE.
UPPER-LEVEL ANALYSIS INDICATES A GENERALLY FAVORABLE ENVIRONMENT WITH
LIGHT (10 TO 15 KNOTS) VERTICAL WIND SHEAR AND GOOD POLEWARD OUTFLOW.
DYNAMIC MODELS INDICATE SLOW DEVELOPMENT OVER THE NEXT 36 HOURS AS THE
SYSTEM TRACKS WEST-SOUTHWESTWARD. MAXIMUM SUSTAINED SURFACE WINDS
ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1004 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
262300Z.//
=========================================================================
WARNING 001 NOT AVAILABLE
=========================================================================
WTXS31 PGTW 20131027 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 01S (ONE) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 01S (ONE) WARNING NR 002
   01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   271200Z --- NEAR 13.1S 64.0E
     MOVEMENT PAST SIX HOURS - 255 DEGREES AT 07 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: 13.1S 64.0E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   280000Z --- 13.2S 61.7E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 24 HR POSIT: 275 DEG/ 10 KTS
    ---
   24 HRS, VALID AT:
   281200Z --- 13.1S 59.7E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 36 HR POSIT: 270 DEG/ 11 KTS
    ---
   36 HRS, VALID AT:
   290000Z --- 13.0S 57.5E
   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 48 HR POSIT: 275 DEG/ 12 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   291200Z --- 12.7S 55.0E
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
271500Z POSITION NEAR 13.1S 63.4E.
TROPICAL CYCLONE 01S (ONE), LOCATED APPROXIMATELY 570 NM NORTHEAST
OF PORT LOUIS, MAURITIUS, HAS TRACKED WEST-SOUTHWESTWARD AT 07 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) DEPICTS AN ELONGATED AND PARTIALLY EXPOSED LOW-LEVEL
CIRCULATION CENTER WITH PERSISTENT CONVECTION THAT HAS BECOME
CONFINED TO THE SOUTHERN SEMI-CIRCLE. THE INITIAL POSITION IS BASED
UPON THE PARTIALLY EXPOSED LLCC SEEN IN THE MSI LOOP WITH FAIR
CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 35 KNOTS BASED ON
DVORAK ESTIMATES RANGING FROM 30 TO 45 KNOTS. UPPER LEVEL ANALYSIS
REVEALS A MODERATE ENVIRONMENT AS INCREASING VERTICAL WIND SHEAR
(VWS),CURRENTLY ASSESSED AT MODERATE TO HIGH LEVELS (15 TO 25 KNOTS),
IS OFFSETTING VIGOROUS POLEWARD OUTFLOW. SEA SURFACE TEMPERATURES IN
THE AREA ARE ALSO ONLY MODERATELY FAVORABLE (26 DEGREES CELSIUS).
TC 01S IS TRACKING GENERALLY WESTWARD ALONG A LOW- TO MID-LEVEL
SUBTROPICAL RIDGE (STR) THAT IS BUILDING EAST OF MADAGASCAR AND
IS EXPECTED TO CONTINUE ALONG THIS BUILDING STR AND TRACK WEST
THROUGH THE REMAINDER OF THE FORECAST. THE SYSTEM IS EXPECTED TO
STRUGGLE TO MAINTAIN TROPICAL CYCLONE STATUS AS FURTHER DECREASING
ENVIRONMENTAL FACTORS ARE EXPECTED TO DISSIPATE THE SYSTEM BELOW
WARNING THRESHOLD BY TAU 48, ALTHOUGH BASED ON THE CURRENTLY
MODERATE ENVIRONMENT, THERE IS A POSSIBILITY OF DISSIPATION BEFORE
THEN. LIMITED DYNAMIC MODEL GUIDANCE CONTINUES TO REMAIN IN GOOD
AGREEMENT; THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC
FORECAST TRACK, WHICH IS POSITIONED CLOSE TO THE MULTI-MODEL
CONSENSUS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 271200Z IS 10 FEET.
NEXT WARNINGS AT 280300Z AND 281500Z.//
=========================================================================
WTXS31 PGTW 20131028 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ:  TROPICAL CYCLONE 01S FINAL WARNING
1. TROPICAL CYCLONE 01S (ONE) WARNING NR 003
   01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   280000Z --- NEAR 13.1S 62.5E
     MOVEMENT PAST SIX HOURS - 260 DEGREES AT 07 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
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   REPEAT POSIT: 13.1S 62.5E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   281200Z --- 13.1S 60.5E
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
280300Z POSITION NEAR 13.1S 62.0E.
TROPICAL CYCLONE (TC) 01S (ONE), LOCATED APPROXIMATELY 550 NM
NORTH-NORTHEAST OF LA REUNION, HAS TRACKED WESTWARD AT 07
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS A FULLY-EXPOSED LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH AN ISOLATED BURST OF CONVECTION OVER THE SOUTH
QUADRANT. A 272241Z TRMM 85GHZ MICROWAVE IMAGE REVEALS AN
ELONGATED LLCC WITH WEAKENING CONVECTIVE BANDING AND A LARGER
AREA OF DEEP CONVECTION DISPLACED WELL TO THE SOUTHEAST OF THE
PRIMARY LLCC. RECENT SCATTEROMETRY DATA INDICATES 15 TO 25 KNOT
CORE WINDS AND 25 TO 30 KNOT GRADIENT WINDS DISPLACED OVER THE SOUTHERN
PERIPHERY OF THE SYSTEM. TC 01S IS WEAKENING QUICKLY AND TRACKING
GENERALLY WESTWARD WITHIN A MARGINAL ENVIRONMENT. THE SYSTEM IS
EXPECTED TO DISSIPATE BY TAU 12. THIS IS THE FINAL WARNING ON THIS
SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL HARBOR HI. THE SYSTEM
WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 280000Z IS 10 FEET.//