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Tropical Cyclone CATHY : JTWC Advisories
Season 1998-1999 Summaries (Operational Data): [AU] [SIO] [SPAC] [SH]
---> Tropical Cyclone CATHY Track Map and Data

WTXS21 PGTW 981224 04:30z
240421Z DEC 98//
REF/A/RMG/NAVPACMETOCCEN WEST GU/240251Z DEC 98//
AMPN/REF IS TROPICAL CYCLONE FORMATION ALERT (WTPS22 PGTW 240300)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
150 NM EITHER SIDE OF A LINE FROM 14.0S5 100.3E4 TO 20.7S9
100.4E5 WITHIN THE NEXT 06 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 20 TO 30 KNOTS.
METSAT IMAGERY AT 240330Z2 INDICATES THAT A CIRCULATION CENTER IS
LOCATED NEAR 15.0S6 100.4E5. THE SYSTEM IS MOVING SOUTHWARD AT
10 KNOTS.
2. REMARKS: ANIMATED INFRARED SATELLITE IMAGERY INDICATES ABUNDANT
DEEP CONVECTION PERSISTS OVER A LOW-LEVEL CYCLONIC CIRCULATION IN
THE SOUTHERN INDIAN OCEAN. OUTFLOW IS GOOD TO THE SOUTHEASTERN
QUADRANT, FAIR ELSEWHERE. THE POTENTIAL FOR DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS GOOD.
3. THIS ALERT VALID UNTIL 250430Z4.
4. SEE REF A FOR DETAILS ON A TROPICAL CYCLONE FORMATION ALERT
LOCATED NEAR 16.7S4 148.5E8.//
=========================================================================
WTXS31 PGTW 981225 03:00z
1. TROPICAL CYCLONE 10S WARNING NR 001
   02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   250000Z7 --- NEAR 16.4S1 99.2E0
     MOVEMENT PAST SIX HOURS - 215 DEGREES AT 04 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
   REPEAT POSIT: 16.4S1 99.2E0
    ---
   FORECASTS:
   12 HRS, VALID AT:
   251200Z0 --- 17.1S9 98.7E4
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 24 HR POSIT: 225 DEG/ 03 KTS
    ---
   24 HRS, VALID AT:
   260000Z8 --- 17.5S3 98.3E0
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 045 NM SOUTHEAST SEMICIRCLE
                            035 NM ELSEWHERE
   VECTOR TO 36 HR POSIT: 240 DEG/ 04 KTS
    ---
   36 HRS, VALID AT:
   261200Z1 --- 17.9S7 97.5E1
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 045 NM SOUTHEAST SEMICIRCLE
                            035 NM ELSEWHERE
   VECTOR TO 48 HR POSIT: 265 DEG/ 06 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   270000Z9 --- 18.0S9 96.2E7
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   RADIUS OF 035 KT WINDS - 050 NM SOUTH SEMICIRCLE
                            045 NM ELSEWHERE
    ---
REMARKS:
250300Z0 POSITION NEAR 16.6S3   99.1E9.
TROPICAL CYCLONE (TC) 10S HAS DEVELOPED SOUTHWEST OF SUMATRA. A
MICROWAVE SCATTEROMETER PASS (241624Z9) INDICATED WINDS OF 35KTS
AROUND THE CENTER. TROPICAL CYCLONE 10S HAS TRACKED SOUTH-
SOUTHWESTWARD AT 6 KNOTS OVER THE PAST 6 HOURS. SATELLITE ANIMATION
AND UW-CIMSS WINDSHEAR PRODUCTS INDICATE TC 10S IS EXPERIENCING
MODERATE VERTICAL WINDSHEAR. IMAGERY ALSO INDICATES THE DEEPER
CONVECTION IS BEING ADVECTED TO THE SOUTHEAST AWAY FROM THE
LOW-LEVEL CIRCULATION CENTER. THE STEERING INFLUENCE IS THE
SUBTROPICAL RIDGE TO THE EAST AND SOUTH. TC 10S IS FORECAST TO
CONTINUE SOUTHWESTWARD AND TURN MORE WESTWARD BY THE 36 HOUR
POSITION AS THE RIDGE TO THE SOUTH BEGINS TO DOMINATE THE STEERING.
TC 1OS IS FORECAST TO INTENSIFY SLIGHTLY AS IT REMAINS IN A MODERATE
WINDSHEAR ENVIRONMENT THROUGHOUT THE PERIOD. WIND RADII ARE OMITTED
UNTIL THE STORM INTENSITY BECOMES GREATER THAN 35 KNOTS. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 250000Z7 IS 12 FEET. THIS WARNING
SUPERSEDES AND CANCELS NAVPACMETOCCEN WEST GU 240421Z
DEC 98 TROPICAL CYCLONE FORMATION ALERT (WTXS21 PGTW 240430). NEXT
WARNINGS AT 251500Z3 (DTG 251351Z7) AND 260300Z1 (DTG 260151Z5).
REFER TO TROPICAL CYCLONE  09P (CORA) WARNINGS (WTXS31 PGTW) FOR
TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 981225 15:00z
SUBJ:  TROPICAL CYCLONE WARNING
1. TROPICAL CYCLONE 10S WARNING NR 002
   02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   251200Z0 --- NEAR 17.0S8 97.4E0
     MOVEMENT PAST SIX HOURS - 255 DEGREES AT 08 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
   REPEAT POSIT: 17.0S8 97.4E0
    ---
   FORECASTS:
   12 HRS, VALID AT:
   260000Z8 --- 17.3S1 95.8E2
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 24 HR POSIT: 260 DEG/ 08 KTS
    ---
   24 HRS, VALID AT:
   261200Z1 --- 17.6S4 94.1E4
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 040 NM SOUTH SEMICIRCLE
                            030 NM ELSEWHERE
   VECTOR TO 36 HR POSIT: 255 DEG/ 09 KTS
    ---
   36 HRS, VALID AT:
   270000Z9 --- 18.1S0 92.2E3
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 040 NM SOUTH SEMICIRCLE
                            030 NM ELSEWHERE
   VECTOR TO 48 HR POSIT: 245 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   271200Z2 --- 18.8S7 90.4E3
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
    ---
REMARKS:
251500Z3 POSITION NEAR 17.1S9 97.0E6.
TROPICAL CYCLONE 10S (TC10S) HAS TRACKED WEST-SOUTHWESTWARD
AT 08 KNOTS WHILE MAINTAINING ITS INTENSITY. CURRENT
INTENSITY IS BASED ON 25/1130Z SATELLITE INTENSITY ESTIMATES
OF T2.0 TO T2.5 (30-35 KT) AND CONTINUITY WITH THE PREVIOUS
WARNING. THE OVERALL STRUCTURE OF TC10S HAS IMPROVED BUT THE
DEEP CONVECTION NEAR THE SYSTEM CENTER HAS WEAKENED
CONSIDERABLY. SATELLITE IMAGERY INDICATES COLD AIR
STRATOCUMULUS CLOUDS BEING DRAWN INTO THE SYSTEM CENTER ON
THE SOUTH SIDE WHICH IS ACTING TO DECREASE CONVECTIVE
DEVELOPMENT. MOST OF THE LOW-LEVEL INFLOW INTO TC10S IS
EXPECTED TO REMAIN FROM THE SOUTH THROUGHOUT THE FORECAST
PERIOD WHILE THE CENTER REMAINS OVER MARGINALLY WARM WATER
(27C SST). AS A RESULT, LITTLE CHANGE IN INTENSITY IS
EXPECTED THROUGH 48 HOURS EVEN THOUGH TC10S IS FORECAST TO
REMAIN IN A LOW SHEAR ENVIRONMENT AND UNDERNEATH A FAVORABLE
200 MB RIDGE AXIS. OWING TO THE LACK OF DEEP CONVECTION...
TC10S IS EXPECTED TO BE STEERED MORE BY THE EASTERLY LOW-
AND MID-LEVEL WIND FLOW ON THE NORTH SIDE OF A STRONG
SUBTROPICAL RIDGE AXIS THAT LIES ALONG 35S LATITUDE. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 251200Z0 IS 12 FEET. NEXT
WARNINGS AT 260300Z1 (DTG 260151Z5) AND 261500Z4 (DTG
261351Z8). REFER TO TROPICAL CYCLONE 09P (CORA) WARNINGS
(WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 981226 03:00z
1. TROPICAL CYCLONE 10S (CATHY) WARNING NR 003
   01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   260000Z8 --- NEAR 16.6S3 95.9E3
     MOVEMENT PAST SIX HOURS - 270 DEGREES AT 09 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
   REPEAT POSIT: 16.6S3 95.9E3
    ---
   FORECASTS:
   12 HRS, VALID AT:
   261200Z1 --- 16.8S5 94.0E3
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 24 HR POSIT: 265 DEG/ 10 KTS
    ---
   24 HRS, VALID AT:
   270000Z9 --- 17.0S8 92.0E1
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 36 HR POSIT: 260 DEG/ 10 KTS
    ---
   36 HRS, VALID AT:
   271200Z2 --- 17.3S1 90.0E9
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   VECTOR TO 48 HR POSIT: 260 DEG/ 11 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   280000Z0 --- 17.6S4 87.7E2
   MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
260300Z1 POSITION NEAR 16.6S3   95.4E8.
TROPICAL CYCLONE 10S (CATHY) HAS TRACKED WESTWARD AT 9 KNOTS OVER
THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 252330Z5 VISIBLE
SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON 252330Z5
SATELLITE INTENSITY ESTIMATES OF 35 KNOTS. VISIBLE SATELLITE IMAGERY
CONFIRMS TROPICAL CYCLONE 10S (CATHY)=S LOW-LEVEL IS BECOMING AN
EXPOSED CIRCULATION.  TROPICAL CYCLONE 10S (CATHY) IS MOVING
WESTWARD IN THE LOW- TO MID-LEVEL STEERING FLOW FROM THE SUBTROPICAL
RIDGE TO IS SOUTH. HOWEVER, THE SYSTEM=S DEEP CONVECTION IS BEING
CARRIED SOUTHWARD IN MID-LEVEL FLOW. TROPICAL CYCLONE 10S (CATHY) IS
FORECAST TO CONTINUE MOVING WESTWARD UNDER THE STEERING INFLUENCE OF
THE RIDGE TO ITS SOUTH. AS THE SYSTEM CONTINUES TO LOSE ITS
CONVECTIVE SUPPORT, IT IS FORECAST TO WEAKEN. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 260000Z8 IS 12 FEET. NEXT WARNINGS AT 261500Z4 (DTG
261351Z8) AND 270300Z2 (DTG 270151Z6).//
=========================================================================
WTXS31 PGTW 981226 15:00z
1. TROPICAL CYCLONE 10S (CATHY) WARNING NR 004
   01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   261200Z1 --- NEAR 16.6S3 94.6E9
     MOVEMENT PAST SIX HOURS - 270 DEGREES AT 07 KTS
     POSITION ACCURATE TO WITHIN 060 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 030 NM SOUTH SEMICIRCLE
                            020 NM ELSEWHERE
   REPEAT POSIT: 16.6S3 94.6E9
    ---
   FORECASTS:
   12 HRS, VALID AT:
   270000Z9 --- 16.6S3 93.2E4
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 020 NM NORTH SEMICIRCLE
                            030 NM ELSEWHERE
   VECTOR TO 24 HR POSIT: 270 DEG/ 07 KTS
    ---
   24 HRS, VALID AT:
   271200Z2 --- 16.6S3 91.7E7
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 36 HR POSIT: 270 DEG/ 08 KTS
    ---
   36 HRS, VALID AT:
   280000Z0 --- 16.6S3 90.0E9
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 48 HR POSIT: 275 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   281200Z3 --- 16.5S2 88.1E7
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
261500Z4 POSITION NEAR 16.6S3 94.2E5.
TROPICAL CYCLONE 10S (CATHY) HAS TRACKED WESTWARD AT 07 KNOTS
THE PAST 06 HOURS. THE WARNING POSITION IS BASED ON ANALYSIS OF
261130Z3 ENHANCED INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY
IS BASED UPON DVORAK SATELLITE INTENSITY ESTIMATES OF CI 2.5 AND 3.0
(35 AND 45 KNOTS) AND CONTINUITY FROM THE PREVIOUS FORECAST.
EARLIER, VISIBLE IMAGERY INDICATED THAT VERTICAL WIND SHEAR REMAINS
ACROSS THE SYSTEM CENTER AND THIS SHOULD REMAIN THROUGHOUT THE
FORECAST PERIOD. THE SYSTEM IS EXPECTED TO TRACK WESTWARD THROUGH 48
HOURS DUE TO LOWER TO MID-LEVEL EASTERLY FLOW FROM RIDGING TO ITS
SOUTH. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 261200Z IS 13 FEET. NEXT
WARNINGS AT 270300Z2 (DTG 270151Z6) AND 271500Z5 (DTG 271351Z9).//
=========================================================================
WTXS31 PGTW 981227 03:00z
1. TROPICAL CYCLONE 10S (CATHY) WARNING NR 005
   01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   270000Z9 --- NEAR 16.7S4 93.6E8
     MOVEMENT PAST SIX HOURS - 260 DEGREES AT 06 KTS
     POSITION ACCURATE TO WITHIN 060 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 040 NM SOUTH SEMICIRCLE
                            035 NM ELSEWHERE
   REPEAT POSIT: 16.7S4 93.6E8
    ---
   FORECASTS:
   12 HRS, VALID AT:
   271200Z2 --- 16.7S4 92.3E4
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   RADIUS OF 035 KT WINDS - 035 NM NORTH SEMICIRCLE
                            040 NM ELSEWHERE
   VECTOR TO 24 HR POSIT: 265 DEG/ 07 KTS
    ---
   24 HRS, VALID AT:
   280000Z0 --- 16.8S5 90.8E7
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 36 HR POSIT: 270 DEG/ 07 KTS
    ---
   36 HRS, VALID AT:
   281200Z3 --- 16.8S5 89.4E1
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   VECTOR TO 48 HR POSIT: 275 DEG/ 07 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   290000Z1 --- 16.7S4 87.9E4
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
270300Z2 POSITION NEAR 16.7S4   93.3E5.
TROPICAL CYCLONE 10S (CATHY) HAS TRACKED WESTWARD AT 6 KNOTS OVER
THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 262330Z6 VISIBLE
SATELLITE IMAGERY. THE WARNING INTENSITY OF 40 KNOTS IS BASED ON AN
AVERAGE OF 262330Z6 SATELLITE INTENSITY ESTIMATES OF 35 AND 45
KNOTS. TROPICAL CYCLONE 10S (CATHY) CONTINUES TO MOVE WESTWARD IN
THE LOW TO MID LEVEL STEERING FLOW FROM THE SUBTROPICAL RIDGE TO ITS
SOUTH. THE SYSTEM=S DEEP CONVECTION REMAINS LOCATED SOUTH OF ITS
LOW-LEVEL, A REFLECTION OF THE WIND SHEAR OCCURRING OVER THE SYSTEM.
SHEAR HAS INTERMITTENTLY RELAXED ALLOWING THE SYSTEM=S DEEP
CONVECTION TO REBUILD OVER THE LOW-LEVEL CIRCULATION CENTER. THIS
HAS ALLOWED TROPICAL CYCLONE 10S (CATHY) TO CONTINUE TO MAINTAIN ITS
PRESENT INTENSITY. TROPICAL CYCLONE 10S (CATHY) IS FORECAST TO
CONTINUE MOVING WESTWARD UNDER THE STEERING INFLUENCE OF THE RIDGE
TO ITS SOUTH. AS TROPICAL CYCLONE 10S (CATHY) TRACKS WESTWARD, IT
WILL MOVE INTO AN ENVIRONMENT OF INCREASING VERTICAL WIND SHEAR.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 270000Z IS 13 FEET. NEXT WARNINGS
AT 271500Z5 (DTG 271351Z9) AND 280300Z3 (DTG 280151Z7).//
=========================================================================
WTXS31 PGTW 981227 15:00z
1. TROPICAL CYCLONE 10S (CATHY) WARNING NR 006
   01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   271200Z2 --- NEAR 16.1S8 92.7E8
     MOVEMENT PAST SIX HOURS - 295 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
   REPEAT POSIT: 16.1S8 92.7E8
    ---
   FORECASTS:
   12 HRS, VALID AT:
   280000Z0 --- 15.8S4 91.4E4
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   VECTOR TO 24 HR POSIT: 280 DEG/ 07 KTS
    ---
   24 HRS, VALID AT:
   281200Z3 --- 15.6S2 90.0E9
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   VECTOR TO 36 HR POSIT: 265 DEG/ 08 KTS
    ---
   36 HRS, VALID AT:
   290000Z1 --- 15.7S3 88.4E0
   MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
271500Z5 POSITION NEAR 16.0S7  92.4E5.
TROPICAL CYCLONE 10S (CATHY) HAS TRACKED WEST-NORTHWESTWARD AT 5
KNOTS OVER THE PAST SIX HOURS. THE WARNING POSITION AND INTENSITY
ARE BASED ON 2271130Z6 INFRARED SATELLITE IMAGERY. RECENT VISIBLE
IMAGERY CONFIRMS THAT THE SYSTEM=S MID-LEVEL AND DEEP CONVECTION IS
COMPLETELY SHEARED, EXPOSING A FAIRLY ORGANIZED SURFACE CIRCULATION
WHICH IS BEING STEERED BY THE LOW-LEVEL FLOW OF RIDGING TO THE
SYSTEMS SOUTH. AS TC 10S (CATHY) IS EXPECTED TO CONTINUE IN A HIGH
VERTICAL SHEAR ENVIRONMENT, DISSIPATION AS A SIGNIFICANT TROPICAL
CYCLONE IS ANTICIPATED NEAR THE 24 HOUR FORECAST POSITION. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 271200Z2 IS 12 FEET. NEXT WARNINGS AT
280300Z3 (DTG 280151Z7) AND 281500Z6 (DTG 281351Z0).//
=========================================================================
WTXS31 PGTW 981228 03:00z
1. TROPICAL CYCLONE 10S (CATHY) WARNING NR 007
   01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   280000Z0 --- NEAR 15.8S4 091.0E0
     MOVEMENT PAST SIX HOURS - 270 DEGREES AT 11 KTS
     POSITION ACCURATE TO WITHIN 060 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   REPEAT POSIT: 15.8S4 091.0E0
    ---
   FORECASTS:
   12 HRS, VALID AT:
   281200Z3 --- 16.1S8 089.0E7
   MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
280300Z3 POSITION NEAR 15.9S5  090.5E4.
TROPICAL CYCLONE 10S (CATHY) HAS TRACKED WESTWARD AT 11
KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED
ON 272330Z7 VISIBLE SATELLITE IMAGERY. THE WARNING INTENSITY IS
BASED ON 272330Z7 SATELLITE INTENSITY ESTIMATES OF 25 KNOTS.
TROPICAL CYCLONE 10S (CATHY) IS A COMPLETELY EXPOSED LOW-LEVEL
CIRCULATION WITH NO ASSOCIATED DEEP CONVECTION. THE SYSTEM IS MOVING
WESTWARD IN THE LOW-LEVEL STEERING FLOW FROM THE RIDGE TO ITS SOUTH.
TROPICAL CYCLONE 10S (CATHY) IS FORECAST TO MOVE WEST-
SOUTHWESTWARD AND DISSIPATE BY THE 12-HOUR FORECAST POSITION
AS IT CONTINUES WITHIN A MODERATE VERTICAL WIND SHEAR ENVIRONMENT.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 280000Z0 IS 12 FEET. THIS IS
THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WARNING
CENTER (NAVPACMETOCCEN WEST GU). THE SYSTEM WILL BE CLOSELY
MONITORED FOR SIGNS OF REGENERATION.//

Tropical cyclone tracks developed by Michael Bath using operational warnings and advisories.


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Document: tropical_cyclone_cathy_jtwc_advisories.htm Updated: 4 September 2016