Updated: 17 June 2020
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| Tropical Cyclones
[Index] | Tropical Cyclone BILLY : JTWC Advisories |
| Season 1998-1999 Summaries (Operational Data): [AU] [SIO] [SPAC] [SH] | |
| ---> Tropical Cyclone BILLY Track Map and Data |
WTXS21 PGTW 981202 08:00z
SUBJ/TROPICAL CYCLONE FORMATION ALERT
020751Z DEC 98//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 14.8S3 121.8E2 TO 18.0S9
117.1E0 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 20 TO 25 KNOTS.
METSAT IMAGERY AT 020530Z INDICATES THAT A CIRCULATION CENTER IS
LOCATED NEAR 15.4S0 120.6E9. THE SYSTEM IS MOVING SOUTH-
SOUTHEASTWARD AT 09 KNOTS.
2. REMARKS:
ANIMATED VISIBLE SATELLITE IMAGERY INDICATES THE AREA OFF THE
NORTHWEST COAST OF AUSTRALIA HAS BECOME MORE ORGANIZED OVER THE PAST
12 HOURS. IN ADDITION, THE UPPER LEVEL ENVIRONMENT REMAINS FAVORABLE
FOR FURTHER DEVELOPMENT. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO
BE 1004 MB. DUE TO THE INCREASED ORGANIZATION OVER THE PAST 12 HOURS
AND THE FAVORABLE UPPER LEVEL ENVIRONMENT, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE IS GOOD.
3. THIS ALERT VALID UNTIL 030800Z1.//
=========================================================================
WTXS31 PGTW 981202 21:00z
1. TROPICAL CYCLONE 05S WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
021800Z1 --- NEAR 16.5S2 119.3E4
MOVEMENT PAST SIX HOURS - 230 DEGREES AT 06 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
REPEAT POSIT: 16.5S2 119.3E4
---
FORECASTS:
12 HRS, VALID AT:
030600Z9 --- 17.2S0 118.6E6
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
VECTOR TO 24 HR POSIT: 225 DEG/ 05 KTS
---
24 HRS, VALID AT:
031800Z2 --- 17.9S7 117.9E8
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
RADIUS OF 035 KT WINDS - 045 NM
VECTOR TO 36 HR POSIT: 225 DEG/ 06 KTS
---
36 HRS, VALID AT:
040600Z0 --- 18.7S6 117.1E0
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 050 NM SOUTHEAST SEMICIRCLE
045 NM ELSEWHERE
VECTOR TO 48 HR POSIT: 225 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
041800Z3 --- 19.6S6 116.2E0
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
RADIUS OF 035 KT WINDS - 055 NM SOUTHEAST SEMICIRCLE
045 NM ELSEWHERE
---
REMARKS:
022100Z5 POSITION NEAR 16.7S4 119.1E2.
TROPICAL CYCLONE 05S HAS DEVELOPED OFF THE NORTHWEST COAST OF
AUSTRALIA. THE WARNING POSITION AND INTENSITY (30 KNOTS) ARE BASED
ON 021130Z7 INFRARED SATELLITE IMAGERY. TROPICAL CYCLONE (TC) 05S
DEVELOPED OVER THE PAST 24 HOURS FROM A DECAYING FRONTAL
BOUNDARY/SHEAR LINE. SATELLITE ANIMATION SHOWS TC 05S HAS BECOME
BETTER ORGANIZED AND HAS A FULLY EXPOSED LOW-LEVEL CIRCULATION
CENTER. ANIMATION ALSO SHOWS CONVECTIVE BANDS NOW SPIRALING AROUND
THE CENTER. SURFACE ANALYSIS INDICATES A DEEPENING CYCLONIC
CIRCULATION WITH A CENTRAL PRESSURE OF ABOUT 1000MB. A 021026Z1
MICROWAVE IMAGER PASS ALSO INDICATED A CIRCULATION CENTER WITH
CONVECTION WRAPPING ABOUT HALF WAY AROUND THE CENTER. UPPER-LEVEL
ANALYSIS AND UNIVERSITY OF WISCONSIN WINDSHEAR PRODUCTS INDICATE
FAVORABLE UPPER LEVEL DIVERGENCE AND WEAK VERTICAL WINDSHEAR OVER
THE AREA. TC 05S SHOULD CONTINUE TO MOVE TOWARDS THE SOUTHWEST
UNDER THE STEERING INFLUENCE OF THE HIGH PRESSURE RIDGE TO THE
SOUTHEAST. TC 05S SHOULD CONTINUE TO SLOWLY INTENSIFY THROUGH THE
PERIOD. AS IT CONTINUES TO MOVE FURTHER SOUTH, TC 05S SHOULD BEGIN
TO EXPERIENCE SLIGHTLY INCREASED VERTICAL WINDSHEAR. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 021800ZZ1 IS 14 FEET. REFER TO WWIO31
PGFW FOR ADDITIONAL SEA HEIGHT INFORMATION.THIS WARNING SUPERSEDES
AND CANCELS NAVPACMETOCCEN WEST GU 020751Z DEC 98 TROPICAL CYCLONE
FORMATION ALERT (WTXS21 PGTW020800) NEXT WARNINGS AT 030300Z6 (DTG
030151Z0), 030900Z2 (DTG 030751Z6), 031500Z9 (DTG 031351Z3) AND
032100Z6 (DTG 031951Z9).//
=========================================================================
WTXS31 PGTW 981203 03:00z
1. TROPICAL CYCLONE 05S WARNING NR 002
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
030000Z3 --- NEAR 17.2S0 118.7E7
MOVEMENT PAST SIX HOURS - 220 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
RADIUS OF 035 KT WINDS - 045 NM SOUTHEAST SEMICIRCLE
035 NM ELSEWHERE
REPEAT POSIT: 17.2S0 118.7E7
---
FORECASTS:
12 HRS, VALID AT:
031200Z6 --- 18.5S4 117.6E5
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 060 NM SOUTHEAST SEMICIRCLE
050 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 210 DEG/ 08 KTS
---
24 HRS, VALID AT:
040000Z4 --- 19.8S8 116.8E6
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
RADIUS OF 035 KT WINDS - 070 NM SOUTHEAST SEMICIRCLE
OVER WATER
055 NM ELSEWHERE OVER WATER
VECTOR TO 36 HR POSIT: 195 DEG/ 08 KTS
---
36 HRS, VALID AT:
041200Z7 --- 21.4S7 116.3E1
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
RADIUS OF 035 KT WINDS - 055 NM EAST SEMICIRCLE
OVER WATER
045 NM ELSEWHERE OVER WATER
VECTOR TO 48 HR POSIT: 170 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
050000Z5 --- 23.2S7 116.7E5
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
RADIUS OF 035 KT WINDS - 035 NM OVER WATER
VECTOR TO 72 HR POSIT: 140 DEG/ 09 KTS
---
72 HRS, VALID AT:
060000Z6 --- 26.1S9 119.3E4
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
030300Z6 POSITION NEAR 17.5S3 118.4E4.
TROPICAL CYCLONE 05S HAS CONTINUED TRACKING TOWARDS THE SOUTHWEST
AT 8 KNOTS. THE WARNING POSITION IS BASED UPON 022330Z0 VISIBLE AND
INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED UPON
SATELLITE CURRENT INTENSITY ESTIMATES OF 35 KNOTS AND A SUPPORTING
SHIP REPORT. TC 05S IS FORECAST TO CONTINUE TO TRACK TOWARDS THE
SOUTHWEST UNDER THE STEERING INFLUENCE OF THE SUBTROPICAL RIDGE TO
ITS SOUTHEAST. THE FORECAST TRACK BECOMES MORE SOUTHWARD BETWEEN THE
24 TO 48 HOUR FORECAST PERIOD AS TC 05S BEGINS TO MOVE AROUND THE
SUBTROPICAL RIDGE. TC 05S IS THEN FORECAST TO TURN MORE
SOUTHEASTWARD AFTER THE 48 HOUR PERIOD IN RESPONSE TO AN APPROACHING
TROUGH FROM THE WEST. AS TC 05S CONTINUES ON ITS FORECAST TRACK, THE
SYSTEM SHOULD BEGIN TO UNDERGO INCREASED VERTICAL SHEAR.
THEREFORE, THE SYSTEM IS EXPECTED TO SLOWLY INTENSIFY UNTIL MAKING
LANDFALL PRIOR TO THE 36 HOUR FORECAST POSITION. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 030000Z3 IS 14 FEET. REFER TO WWIO31 PGFW FOR
ADDITIONAL SEA HEIGHT INFORMATION. NEXT WARNINGS AT 030900Z2 (DTG
030751Z6), 031500Z9 (DTG 031351Z3), 032100Z6 (DTG 031951Z9) AND
040300Z7 (DTG 040151Z1).//
=========================================================================
WTXS31 PGTW 981203 09:00z
1. TROPICAL CYCLONE 05S WARNING NR 003
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
030600Z9 --- NEAR 17.0S8 118.1E1
MOVEMENT PAST SIX HOURS - 280 DEGREES AT 06 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
RADIUS OF 035 KT WINDS - 060 NM SOUTH SEMICIRCLE
040 NM ELSEWHERE
REPEAT POSIT: 17.0S8 118.1E1
---
FORECASTS:
12 HRS, VALID AT:
031800Z2 --- 16.9S6 117.1E0
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
RADIUS OF 035 KT WINDS - 060 NM SOUTH SEMICIRCLE
040 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 255 DEG/ 06 KTS
---
24 HRS, VALID AT:
040600Z0 --- 17.2S0 115.9E6
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
RADIUS OF 035 KT WINDS - 065 NM SOUTH SEMICIRCLE
055 NM ELSEWHERE
VECTOR TO 36 HR POSIT: 235 DEG/ 07 KTS
---
36 HRS, VALID AT:
041800Z3 --- 18.0S9 114.6E2
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
055 NM ELSEWHERE
VECTOR TO 48 HR POSIT: 225 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
050600Z1 --- 19.2S2 113.3E8
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 72 HR POSIT: 205 DEG/ 08 KTS
---
72 HRS, VALID AT:
060600Z2 --- 22.0S4 111.8E1
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
030900Z2 POSITION NEAR 17.0S8 117.8E7.
TROPICAL CYCLONE 05S HAS BEGUN TRACKING WESTWARD AT 6 KNOTS DURING
THE PAST 6 HOURS. THE WARNING POSITION IS BASED UPON AN EARLIER
030038Z4 MICROWAVE IMAGER PASS AND 030530Z1 VISIBLE SATELLITE
IMAGERY. THE WARNING INTENSITY IS BASED UPON SATELLITE CURRENT
INTENSITY ESTIMATES OF 35 KNOTS AND PREVIOUS SUPPORTING SHIP
REPORTS. ANIMATED VISIBLE AND INFRARED SATELLITE IMAGERY INDICATE A
SIGNIFICANTLY MORE WESTWARD TRACK THAN THAT OF THE PREVIOUS
FORECAST. WEAKENED STEERING FLOW AND THE SYSTEM=S ASYMMETRIC
STRUCTURE MAY BE RESPONSIBLE FOR THE SUDDEN TRACK CHANGE AND SLOWER
MOVEMENT. TROPICAL CYCLONE 05S IS LOCATED BETWEEN THE SUBTROPICAL
RIDGE TO ITS SOUTHEAST AND AN APPROACHING TROUGH TO ITS SOUTHWEST,
CAUSING THE AFOREMENTIONED WEAKENED STEERING FLOW. TROPICAL CYCLONE
05S IS FORECAST TO CONTINUE ON THIS WESTWARD TRACK OVER THE NEXT 12
HOURS UNTIL RETURNING TO A MORE DOMINANT STEERING FLOW AHEAD OF THE
TROUGH, RESULTING IN A MORE SOUTHWESTWARD TRACK AFTER THE 24 HOURS
FORECAST POSITION. TROPICAL CYCLONE 05S IS EXPECTED TO BEGIN TO
UNDERGO INCREASING SHEAR AS THE DOMINANT STEERING FLOW REINSTATES.
THEREFORE, TROPICAL CYCLONE 05S IS FORECAST TO STRENGTHEN ONLY
SLIGHTLY THROUGHOUT THE 36 HOUR FORECAST PERIOD, THEN IS EXPECTED TO
BEGIN TO DISSIPATE OVER WATER THROUGHOUT THE REMAINDER OF THE
FORECAST PERIOD. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 030600Z IS 14
FEET. REFER TO WWIO30 PGFW FOR ADDITIONAL SEA HEIGHT INFORMATION.
NEXT WARNINGS AT 031500Z9 (DTG 031351Z3), 032100Z6 (DTG 031951Z9),
040300Z7 (DTG 040151Z1) AND 040900Z3 (DTG 040751Z7).//
=========================================================================
WTXS31 PGTW 981203 21:00z
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 005
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
031800Z2 --- NEAR 17.5S3 117.4E3
MOVEMENT PAST SIX HOURS - 250 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 065 NM SOUTH SEMICIRCLE
045 NM ELSEWHERE
REPEAT POSIT: 17.5S3 117.4E3
---
FORECASTS:
12 HRS, VALID AT:
040600Z0 --- 17.8S6 116.8E6
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 075 NM SOUTH SEMICIRCLE
060 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 240 DEG/ 05 KTS
---
24 HRS, VALID AT:
041800Z3 --- 18.3S2 115.9E6
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
RADIUS OF 035 KT WINDS - 080 NM SOUTH SEMICIRCLE
070 NM ELSEWHERE
VECTOR TO 36 HR POSIT: 235 DEG/ 06 KTS
---
36 HRS, VALID AT:
050600Z1 --- 19.0S0 114.9E5
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
060 NM ELSEWHERE
VECTOR TO 48 HR POSIT: 225 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
051800Z4 --- 20.0S2 113.9E4
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
RADIUS OF 035 KT WINDS - 070 NM SOUTHEAST SEMICIRCLE
055 NM ELSEWHERE
VECTOR TO 72 HR POSIT: 210 DEG/ 07 KTS
---
72 HRS, VALID AT:
061800Z5 --- 22.6S0 112.4E8
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
RADIUS OF 035 KT WINDS - 065 NM EAST SEMICIRCLE
045 NM ELSEWHERE
---
REMARKS:
032100Z6 POSITION NEAR 17.6S4 117.3E2.
TROPICAL CYCLONE 05S (BILLY) HAS BEEN TRACKING WEST-SOUTHWESTWARD
AT 3 KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON
031730Z4 INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS
BASED ON 031730Z4 SATELLITE INTENSITY ESTIMATES OF 45 KNOTS.
TROPICAL CYCLONE 05S (BILLY) HAS BEEN MOVING SLOWLY WEST-
SOUTHWESTWARD IN THE STEERING FLOW FROM THE SUBTROPICAL RIDGE TO ITS
SOUTH. THIS STEERING SHOULD REMAIN THE DOMINANT STEERING INFLUENCE
THROUGHOUT THE FORECAST PERIOD. TROPICAL CYCLONE 05S (BILLY)
IS FORECAST TO MOVE WEST-SOUTHWESTWARD AND THEN SOUTHWESTWARD
AS THE RIDGE GRADUALLY WEAKENS DUE TO AN APPROACHING MID-
LATITUDE TROUGH. TROPICAL CYCLONE 05S (BILLY) IS FORECAST
TO CONTINUE TO INTENSIFY UNTIL THE 24-HOUR TRACK POSITION AT WHICH
TIME THE SYSTEM SHOULD BEGIN TO ENCOUNTER INCREASING VERTICAL
WIND SHEAR. ENHANCED INFRARED IMAGERY AND MICROWAVE IMAGERY SHOW
THE DEEP CONVECTION ASSOCIATED WITH TROPICAL CYCLONE 05S (BILLY)
IS LOCATED WEST OF THE LOW-LEVEL CIRCULATION CENTER SUGGESTING
THE SYSTEM IS BEGINNING TO EXPERIENCE INCREASING WIND SHEAR AS IT
MOVES AGAINST THE SUBTROPICAL RIDGE. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 031800Z IS 15 FEET. NEXT WARNINGS AT 040300Z7 (DTG
040151Z1), 040900Z3 (DTG 040751Z7), 041500Z0 (DTG 041351Z4) AND
042100Z7 (DTG 041951Z0).//
=========================================================================
warning 006 not available
=========================================================================
WTXS31 PGTW 981204 09:00z
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
040600Z0 --- NEAR 18.5S4 116.6E4
MOVEMENT PAST SIX HOURS - 225 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE AND RADAR
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
RADIUS OF 050 KT WINDS - 025 NM SOUTHEAST SEMICIRCLE
020 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
050 NM ELSEWHERE
REPEAT POSIT: 18.5S4 116.6E4
---
FORECASTS:
12 HRS, VALID AT:
041800Z3 --- 19.3S3 115.8E5
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 020 NM SOUTHEAST SEMICIRCLE
015 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 070 NM SOUTHEAST SEMICIRCLE
055 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 210 DEG/ 09 KTS
---
24 HRS, VALID AT:
050600Z1 --- 20.8S0 114.9E5
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
RADIUS OF 050 KT WINDS - 020 NM SOUTHEAST SEMICIRCLE
015 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
OVER WATER
055 NM ELSEWHERE OVER WATER
VECTOR TO 36 HR POSIT: 205 DEG/ 09 KTS
---
36 HRS, VALID AT:
051800Z4 --- 22.5S9 114.1E7
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
OVER WATER
050 NM ELSEWHERE OVER WATER
VECTOR TO 48 HR POSIT: 215 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
060600Z2 --- 23.6S1 113.3E8
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 050 NM SOUTHEAST SEMICIRCLE
OVER WATER
035 NM ELSEWHERE OVER WATER
VECTOR TO 72 HR POSIT: 225 DEG/ 06 KTS
---
72 HRS, VALID AT:
070600Z3 --- 25.3S0 111.3E6
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
040900Z3 POSITION NEAR 18.7S6 116.4E2.
TROPICAL CYCLONE 05S (BILLY) HAS TRACKED SOUTHWESTWARD AT 04 KNOTS
THE PAST 06 HOURS. THE WARNING POSITION IS BASED UPON A COMBINATION
OF 040640Z4 RADAR IMAGERY FROM WMO NUMBER 94308 (DAMPIER, AUSTRALIA)
AND ANALYSIS OF 04530Z2 VISIBLE SATELLITE IMAGERY. RADAR IMAGERY
STILL INDICATES THE THE PRESENCE OF A 13NM DIAMETER EYE. ANIMATED
SATELLITE IMAGERY SUGGESTS THAT VERTICAL WIND SHEAR HAS BEGUN TO
AFFECT THE SYSTEM OVER THE PAST SEVERAL HOURS AS THE EYE FEATURE IS
NO LONGER DISCERNABLE DUE TO CIRRUS CLOUD COVER. WITH STRONGER WEST-
NORTHWESTERLY WINDS LOCATED TO THE SOUTH, IT APPEARS THAT THE SYSTEM
HAS PEAKED AND WILL BEGIN WEAKENING SOON DUE TO THE INCREASING
VERTICAL WIND SHEAR. THIS WEAKENING TREND WILL CONTINUE THROUGH THE
REMAINDER OF THE FORECAST PERIOD. WITH THE EXCEPTION OF SOME
SLIGHTLY SLOWER FORWARD MOTION SPEEDS, THERE IS NO SIGNIFICANT
CHANGE TO THE FORECAST TRACK AND INTENSITY PHILOSOPHY. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 040600Z IS 14 FEET. REFER TO WWPIO30
PGFW FOR ADDITIONAL SEA HEIGHT INFORMATION. NEXT WARNINGS AT
041500Z0 (DTG 041351Z4), 042100Z7 (DTG 041951Z0), 050300Z8 (DTG
050151Z2) AND 050900Z4 (DTG 050751Z8).//
=========================================================================
WTXS31 PGTW 981204 15:00z
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 008
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
041200Z7 --- NEAR 18.9S8 116.4E2
MOVEMENT PAST SIX HOURS - 205 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
RADIUS OF 050 KT WINDS - 025 NM SOUTHEAST SEMICIRCLE
020 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
060 NM ELSEWHERE
REPEAT POSIT: 18.9S8 116.4E2
---
FORECASTS:
12 HRS, VALID AT:
050000Z5 --- 19.7S7 116.0E8
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 020 NM SOUTHEAST SEMICIRCLE
015 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
OVER WATER
060 NM ELSEWHERE OVER WATER
VECTOR TO 24 HR POSIT: 200 DEG/ 06 KTS
---
24 HRS, VALID AT:
051200Z8 --- 20.8S0 115.6E3
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
RADIUS OF 050 KT WINDS - 020 NM SOUTHEAST SEMICIRCLE
015 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 070 NM SOUTHEAST SEMICIRCLE
OVER WATER
055 NM ELSEWHERE OVER WATER
VECTOR TO 36 HR POSIT: 205 DEG/ 06 KTS
---
36 HRS, VALID AT:
060000Z6 --- 21.9S2 115.1E8
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
OVER WATER
050 NM ELSEWHERE OVER WATER
VECTOR TO 48 HR POSIT: 210 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
061200Z9 --- 22.9S3 114.5E1
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
RADIUS OF 035 KT WINDS - 055 NM SOUTHEAST SEMICIRCLE
OVER WATER
045 NM ELSEWHERE OVER WATER
VECTOR TO 72 HR POSIT: 215 DEG/ 05 KTS
---
72 HRS, VALID AT:
071200Z0 --- 24.5S1 113.3E8
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
041500Z0 POSITION NEAR 19.1S1 116.3E1.
TROPICAL CYCLONE 05S (BILLY) HAS BEEN TRACKING SOUTH-SOUTHWESTWARD
AT 4 KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED
ON 041130Z9 INFRARED SATELLITE IMAGERY, EXTRAPOLATION FROM A
040949Z6 MICROWAVE IMAGER PASS AND ANIMATION. THE WARNING INTENSITY
IS BASED ON 041130Z9 SATELLITE INTENSITY ESTIMATE OF 65 KNOTS.
TROPICAL CYCLONE 05S (BILLY) HAS PEAKED IN INTENSITY OVER THE
PAST 12 HOURS AND THE SYSTEM IS NO LONGER DISPLAYING AN EYE
FEATURE. TROPICAL CYCLONE 05S (BILLY) IS SLOWLY MOVING SOUTH-
SOUTHWESTWARD IN THE STEERING FLOW FROM THE SUBTROPICAL RIDGE TO ITS
SOUTH-SOUTHEAST AND THE MID-LATITUDE TROUGH TO ITS SOUTHWEST.
TROPICAL CYCLONE 05S (BILLY) IS FORECAST TO MAKE LANDFALL AFTER THE
24-HOUR TRACK POSITION. ANIMATED INFRARED IMAGERY SHOWS THE SYSTEM=S
DEEP CONVECTION IS BEGINNING TO BE CARRIED SOUTHWARD IN THE MID-
LEVEL STEERING FLOW. TROPICAL CYCLONE 05S (BILLY) IS FORECAST TO
CONTINUE SOUTH-SOUTHWESTWARD THROUGHOUT THE 36-HOUR FORECAST TRACK
POSITION, SLOWLY WEAKENING AS IT ENCOUNTERS INCREASING VERTICAL WIND
SHEAR. AFTER THE 36-HOUR TRACK POSITION, THE WEAKENING SYSTEM WILL
BEGIN TO MOVE MORE WESTWARD AS IT BEGINS TO BECOME MORE INFLUENCED
BY THE LOW LEVEL STEERING FLOW. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
041200Z IS 14 FEET. NEXT WARNINGS AT 042100Z7 (DTG 041951Z0),
050300Z8 (DTG 050151Z2), 050900Z4 (DTG 050751Z8) AND 051500Z1 (DTG
051351Z5).//
=========================================================================
WTXS31 PGTW 981204 21:00z
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 009
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
041800Z3 --- NEAR 18.9S8 116.4E2
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 02 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 025 NM SOUTHEAST SEMICIRCLE
020 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
070 NM ELSEWHERE
REPEAT POSIT: 18.9S8 116.4E2
---
FORECASTS:
12 HRS, VALID AT:
050600Z1 --- 19.6S6 116.1E9
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 020 NM SOUTHEAST SEMICIRCLE
015 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
OVER WATER
070 NM ELSEWHERE OVER WATER
VECTOR TO 24 HR POSIT: 200 DEG/ 05 KTS
---
24 HRS, VALID AT:
051800Z4 --- 20.6S8 115.7E4
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
OVER WATER
060 NM ELSEWHERE OVER WATER
VECTOR TO 36 HR POSIT: 195 DEG/ 06 KTS
---
36 HRS, VALID AT:
060600Z2 --- 21.8S1 115.3E0
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 055 NM SOUTHEAST SEMICIRCLE
OVER WATER
050 NM ELSEWHERE OVER WATER
VECTOR TO 48 HR POSIT: 210 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
061800Z5 --- 22.8S2 114.7E3
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
RADIUS OF 035 KT WINDS - 050 NM SOUTHEAST SEMICIRCLE
OVER WATER
045 NM ELSEWHERE OVER WATER
VECTOR TO 72 HR POSIT: 215 DEG/ 06 KTS
---
72 HRS, VALID AT:
071800Z6 --- 24.7S3 113.3E8
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
042100Z7 POSITION NEAR 19.1S1 116.3E1.
TROPICAL CYCLONE 05S (BILLY) HAS BEEN DRIFTING SOUTHWARD
AT 2 KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS
BASED ON 041730Z5 INFRARED SATELLITE IMAGERY AND EXTRAPOLATION
FROM A 041318Z7 MICROWAVE IMAGER PASS. THE WARNING INTENSITY OF 60
KNOTS IS BASED ON AN AVERAGE OF 041730Z5 SATELLITE INTENSITY
ESTIMATES. TROPICAL CYCLONE 05S (BILLY)IS DRIFTING SLOWLY SOUTHWARD
IN THE STEERING FLOW FROM THE SUBTROPICAL RIDGE TO ITS SOUTHEAST.
ANIMATED SATELLITE IMAGERY SHOWS THE SYSTEM BEGINNING TO ELONGATE AS
THE DEEP CONVECTION MOVES SOUTHWARD. TROPICAL CYCLONE 05S (BILLY)=S
LOW-LEVEL IS DIFFICULT TO LOCATE USING INFRARED IMAGERY AND THE
WARNING POSITION WAS EXTRAPOLATED FROM A MICROWAVE IMAGER PASS
WHICH SHOWED THE LOW-LEVEL NORTH OF THE DEEP CONVECTION. TROPICAL
CYCLONE 05S (BILLY) IS FORECAST TO CONTINUE MOVING SOUTHWARD
AND SOUTHWESTWARD IN THE MID-LEVEL STEERING FLOW AND IS FORECAST
TO MAKE LANDFALL AFTER THE 24-HOUR TRACK POSITION. TROPICAL
CYCLONE 05S (BILLY) HAS WEAKENED OVER THE PAST 6 HOURS.
AS THE SYSTEM MOVES SOUTHWARD IT WILL CONTINUE TO ENCOUNTER
INCREASING VERTICAL WIND SHEAR, AS WELL AS LAND INTERACTION
AFTER IT MAKES LANDFALL, WHICH WILL FURTHER WEAKEN THE SYSTEM.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 041800Z IS 14 FEET. NEXT
WARNINGS AT 050300Z8 (DTG 050151Z2), 050900Z4 (DTG 050751Z8),
051500Z1 (DTG 051351Z5) AND 052100Z8 (DTG 051951Z1).//
=========================================================================
WTXS31 PGTW 981205 03:00z
SUBJ: TROPICAL CYCLONE WARNING
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 010
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
050000Z5 --- NEAR 19.4S4 116.4E2
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 025 NM SOUTHEAST SEMICIRCLE
020 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
OVER WATER
070 NM ELSEWHERE
REPEAT POSIT: NEAR 19.4S4 116.4E2
---
FORECASTS:
12 HRS, VALID AT:
051200Z8 --- 20.2S4 116.3E1
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
OVER WATER
060 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 190 DEG/ 04 KTS
---
24 HRS, VALID AT:
060000Z6 --- 20.9S1 116.2E0
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 055 NM SOUTHEAST SEMICIRCLE
OVER WATER
045 NM ELSEWHERE
VECTOR TO 36 HR POSIT: 200 DEG/ 04 KTS
---
36 HRS, VALID AT:
061200Z9 --- 21.7S0 115.9E6
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 195 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
070000Z7 --- 22.5S9 115.7E4
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
050300Z8 POSITION NEAR 19.6S6 116.4E2.
TROPICAL CYCLONE 05S (BILLY) HAS TRACKED SOUTHWARD AT 3 KNOTS OVER
THE PAST 6 HOURS. THE WARNING POSITION IS BASED UPON 042330Z2
INFRARED SATELLITE IMAGE, AND THE WARNING INTENSITY IS BASED UPON A
SATELLITE CURRENT INTENSITY ESTIMATE OF 65 KNOTS AS WELL AS
CONTINUITY WITH THE PREVIOUS FORECAST. ANIMATED WATER VAPOR
SATELLITE IMAGERY CONTINUES TO SHOW THAT TC 05S (BILLY) IS
UNDERGOING MODERATE TO STRONG UPPER LEVEL WIND SHEAR. ALTHOUGH TC
05S (BILLY) CONTINUES TO BE STEERED BY THE HIGH PRESSURE SYSTEM TO
ITS SOUTHEAST, THE HIGH PRESSURE SYSTEM IS FORECAST TO CHANGE ITS
ORIENTATION TO ALLOW FOR THE MORE SOUTHWARDLY TRACK. DUE TO THE HIGH
SHEAR ENVIRONMENT, TC 05S (BILLY) SHOULD NOT INTENSIFY AS IT
APPROACHES LANDFALL AND SHOULD RAPIDLY DISSIPATE AS IT TRACKS OVER
THE NORTHERN COAST OF AUSTRALIA BY THE 24 HOUR FORECAST POSITION.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 050000Z5 IS 14 FEET. NEXT
WARNINGS AT 050900Z4 (DTG 050751Z8), 051500Z1 (DTG 051351Z5),
052100Z8 (DTG 051951Z1) AND 060300Z9 (DTG 060151Z3).//
=========================================================================
WTXS31 PGTW 050900
SUBJ: TROPICAL CYCLONE WARNING
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 011
01 ACTIVE TROPICAL CYCLONE IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
050600Z1 --- NEAR 19.5S5 115.3E0
MOVEMENT PAST SIX HOURS - 225 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 050 KT WINDS - 025 NM SOUTHEAST SEMICIRCLE
020 NM ELSEWHERE
RADIUS OF 035 KT WINDS - 075 NM SOUTHEAST SEMICIRCLE
070 NM ELSEWHERE
REPEAT POSIT: NEAR 19.5S5 115.3E0
---
FORECASTS:
12 HRS, VALID AT:
051800Z4 --- 19.9S9 114.9E5
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 065 NM SOUTHEAST SEMICIRCLE
060 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 195 DEG/ 04 KTS
---
24 HRS, VALID AT:
060600Z2 --- 20.6S8 114.7E3
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 055 NM SOUTHEAST SEMICIRCLE
045 NM ELSEWHERE
VECTOR TO 36 HR POSIT: 180 DEG/ 03 KTS
---
36 HRS, VALID AT:
061800Z5 --- 21.1S4 114.6E2
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 055 NM SOUTHEAST SEMICIRCLE
OVER WATER
045 NM ELSEWHERE
VECTOR TO 48 HR POSIT: 180 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
070600Z3 --- 21.8S1 114.5E1
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
RADIUS OF 035 KT WINDS - 040 NM OVER WATER
VECTOR TO 72 HR POSIT: 185 DEG/ 04 KTS
---
72 HRS, VALID AT:
080600Z4 --- 23.2S7 114.3E9
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
050900Z4 POSITION NEAR 19.6S6 115.2E9.
TROPICAL CYCLONE 05S (BILLY) HAS TRACKED SOUTHWESTWARD AT 03 KNOTS
OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED UPON A
050530Z3 VISIBLE SATELLITE IMAGE, AND THE WARNING INTENSITY IS
BASED UPON A CURRENT INTENSITY ESTIMATE OF 65 KNOTS BUT TAKES INTO
ACCOUNT THE INCREASED SHEAR ENVIRONMENT. THE CURRENT POSITION OF
TC 05S (BILLY) HAS BEEN LOCATED FURTHER WEST FROM THE PREVIOUS
FORECAST DUE TO THE VISIBLE SATELLITE IMAGERY. THE ANIMATED VISIBLE
SATELLITE IMAGERY SHOWS TC 05S (BILLY) CONTINUES TO BE UNDER MODERATE
TO HIGH VERTICAL WIND SHEAR AS MOST OF THE CONVECTION HAS SHEARED AWAY
TO THE SOUTHEAST. TROPICAL CYCLONE 05S (BILLY) SHOULD COUNTINUE TO
DISSIPATE AS IT APPROACHES THE NORTHWEST COAST OF AUSTRALIA DUE TO THE
INCREASED SHEAR ENVIRONMENT. AFTER MAKING LANDFALL, TC 05S (BILLY)
SHOULD DISSIPATE EVEN MORE RAPIDLY. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
050600Z IS 14 FEET. NEXT WARNINGS AT 051500Z1 (DTG 051351Z5), 052100Z8
(DTG 051951Z1), 060300Z9 (DTG 060151Z3) AND 060900Z5 (DTG 060751Z9).//
=========================================================================
WTXS31 PGTW 981205 15:00z
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 012
02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
051200Z8 --- NEAR 20.1S3 115.2E9
MOVEMENT PAST SIX HOURS - 190 DEGREES AT 05 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 050 NM SOUTHEAST SEMICIRCLE
040 NM ELSEWHERE
REPEAT POSIT: NEAR 20.1S3 115.2E9
---
FORECASTS:
12 HRS, VALID AT:
060000Z6 --- 21.1S4 114.9E5
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 040 NM SOUTHEAST SEMICIRCLE
OVER WATER
030 NM ELSEWHERE OVER WATER
VECTOR TO 24 HR POSIT: 190 DEG/ 05 KTS
---
24 HRS, VALID AT:
061200Z9 --- 22.1S5 114.7E3
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 36 HR POSIT: 180 DEG/ 05 KTS
---
36 HRS, VALID AT:
070000Z7 --- 23.1S6 114.6E2
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 180 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
071200Z0 --- 24.2S8 114.6E2
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
051500Z1 POSITION NEAR 20.4S6 115.1E8.
TROPICAL CYCLONE 05S (BILLY) HAS TRACKED SOUTHWARD AT 05 KNOTS
OVER THE PAST 6 HOURS. THE WARNING POSITION AND CURRENT INTENSITY
(45KTS) ARE BASED ON A COMBINATION OF 051130Z0 INFRARED SATELLITE
IMAGE ANALYSIS TECHNIQUES (55KTS) AND SCATTEROMETRY DATA (45 KTS).
THE MICROWAVE SCATTEROMETER PASS (050220Z9) INDICATED THE SYSTEM HAS
WEAKENED CONSIDERABLY IN THE PAST 12 HOURS. ANIMATED SATELLITE
IMAGERY ALSO REVEALS A FLARE-UP OF DEEP CONVECTION AROUND THE SYSTEM
OVER THE LAST THREE HOURS. THIS INCREASE IN CONVECTION AROUND THE
CENTER INDICATES A TEMPORARY WEAKENING OF VERTICAL WINDSHEAR. UW
CIMSS WINDSHEAR PRODUCTS ALSO SHOW TC 05S (BILLY) IS MOVING INTO AN
AREA OF MODERATE VERTICAL WIND SHEAR. TC 05S (BILLY) SHOULD CONTINUE
TO SLOWLY TRACK SOUTHWARD UNDER THE INFLUENCE OF THE SUBTROPICAL
RIDGE TO THE SOUTHEAST. TROPICAL CYCLONE 05S (BILLY) SHOULD ALSO
COUNTINUE TO WEAKEN AS IT APPROACHES THE NORTHWEST COAST OF
AUSTRALIA DUE TO THE INCREASED WINDSHEAR ENVIRONMENT. AFTER MAKING
LANDFALL, TC 05S (BILLY) SHOULD DISSIPATE EVEN MORE RAPIDLY DUE TO
LAND INTERACTION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 051200Z8 IS 14
FEET. REFER TO WWIO31 PGFW FOR ADDITIONAL SEA HEIGHT INFORMATION.
NEXT WARNINGS AT 052100Z8 (DTG 051951Z1), 060300Z9 (DTG 060151Z3),
060900Z5 (DTG 060751Z9) AND 061500Z2 (DTG 061351Z6).REFER TO
TROPICAL CYCLONE 06S (NONAME) WARNINGS (WTXS32 PGTW) FOR SIX-HOURLY
UPDATES.//
=========================================================================
WTXS31 PGTW 981205 21:00z COR
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 013 CORRECTED
02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
051800Z4 --- NEAR 20.3S5 115.0E7
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 02 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 035 KT WINDS - 050 NM SOUTHEAST SEMICIRCLE
040 NM ELSEWHERE
REPEAT POSIT: 20.3S5 115.0E7
---
FORECASTS:
12 HRS, VALID AT:
060600Z2 --- 20.8S0 114.8E4
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 040 NM SOUTHEAST SEMICIRCLE
030 NM ELSEWHERE
VECTOR TO 24 HR POSIT: 200 DEG/ 03 KTS
---
24 HRS, VALID AT:
061800Z5 --- 21.3S6 114.6E2
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 36 HR POSIT: 180 DEG/ 04 KTS
---
36 HRS, VALID AT:
070600Z3 --- 22.0S4 114.5E1
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 180 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
071800Z6 --- 22.9S3 114.4E0
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 72 HR POSIT: 180 DEG/ 05 KTS
---
72 HRS, VALID AT:
081800Z7 --- 24.8S4 114.3E9
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
052100Z8 POSITION NEAR 20.4S6 115.0E7.
TROPICAL CYCLONE 05S (BILLY) HAS DRIFTED SOUTHWARD AT 02 KNOTS
OVER THE PAST 6 HOURS. THE WARNING POSITION AND CURRENT INTENSITY
(45KTS) ARE BASED ON 051730Z6 INFRARED SATELLITE IMAGE ANALYSIS
TECHNIQUES AND A MICROWAVE IMAGER PASS (051253Z6). ANIMATED
SATELLITE IMAGERY INDICATES THE SYSTEM HAS BECOME QUASI-STATIONARY
OVER THE PAST 6 HOURS. THE MICROWAVE PASS INDICATES THE LOW-LEVEL
CIRCULATION CENTER HAS BECOME EXPOSED. THIS EXPOSURE WOULD INDICATE
AN INCREASE IN VERTICAL WINDSHEAR. SYNOPTIC WIND REPORTS FROM
BARROW=S ISLAND AUSTRALIA (WMO 94304) OVER THE PAST SEVERAL HOURS
INDICATE THE SYSTEM IS IS QUASI-STATIONARY. UW CIMSS WINDSHEAR
PRODUCTS AND ANIMATED WATER VAPOR IMAGERY INDICATE TC 05S (BILLY) IS
MOVING INTO AN AREA OF MODERATE VERTICAL WINDSHEAR. ANIMATION ALSO
REVEALS SEVERAL OUTFLOW BOUNDARIES FROM THUNDERSTORMS INTERSECTING
IN THE VICINITY OF THE SYSTEM. TC 05S (BILLY) IS FORECAST TO
CONTINUE TO DRIFT SOUTHWARD WITH THE LOW-MID LEVEL STEERING FLOW OF
THE SUBTROPICAL RIDGE TO THE SOUTH. TROPICAL CYCLONE 05S (BILLY)
SHOULD ALSO COUNTINUE TO WEAKEN AS IT APPROACHES THE NORTHWEST COAST
OF AUSTRALIA DUE TO THE INCREASED WINDSHEAR ENVIRONMENT. AFTER
MAKING LANDFALL, TC 05S (BILLY) SHOULD DISSIPATE EVEN MORE RAPIDLY
DUE TO LAND INTERACTION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 051800Z4
IS 14 FEET. NEXT WARNINGS AT 060300Z9 (DTG 060151Z3), 060900Z5 (DTG
060751Z9), 061500Z2 (DTG 061351Z6) AND 062100Z9 (DTG 061951Z2).
REFER TO TROPICAL CYCLONE 06S WARNINGS (WTXS32 PGTW)
FOR TWELVE-HOURLY UPDATES.
2. JUSTIFICATION FOR CORRECTION: TO REMOVE REFERENCE TO WWIO31 AND
CHANGE TROPICAL CYCLONE 06S TO REFLECT 12 HOUR WARNINGS IN THE
REMARKS SECTION.//
=========================================================================
WTXS31 PGTW 981206 03:00z
SUBJ: TROPICAL CYCLONE WARNING
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 014
02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
060000Z6 --- NEAR 20.8S0 114.9E5
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 04 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
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 035 KT WINDS - 040 NM SOUTHEAST SEMICIRCLE
030 NM ELSEWHERE
REPEAT POSIT: NEAR 20.8S0 114.9E5
---
FORECASTS:
12 HRS, VALID AT:
061200Z9 --- 21.3S6 114.8E4
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 24 HR POSIT: 195 DEG/ 03 KTS
---
24 HRS, VALID AT:
070000Z7 --- 21.9S2 114.6E2
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 36 HR POSIT: 180 DEG/ 04 KTS
---
36 HRS, VALID AT:
071200Z0 --- 22.8S2 114.5E1
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
060300Z9 POSITION NEAR 20.9S1 114.9E5.
TROPICAL CYCLONE 05S (BILLY) HAS TRACKED SOUTHWARD AT 4 KNOTS OVER
THE PAST 6 HOURS. THE WARNING POSITION IS BASED UPON A 052330Z3
VISIBLE SATELLITE IMAGE. THE WARNING INTENSITY IS BASED UPON A
COMBINATION OF A SATELLITE CURRENT INTENSITY ESTIMATE OF 35 KNOTS
AND CONTINUITY WITH THE PREVIOUS FORECAST. TROPICAL CYCLONE 05S
(BILLY) CONTINUES TO TRACK SLOWLY SOUTHWARD TOWARDS THE NORTHWEST
COAST OF AUSTRALIA NEAR PORT EXMOUTH. ALTHOUGH THE STEERING
INFLUENCE REMAINS THE HIGH PRESSURE SYSTEM TO THE SOUTHEAST, TC 05S
(BILLY) IS IN AN AREA WITH LIGHT LOW LEVEL STEERING, WHICH ACCOUNTS
FOR ITS SLOW MOVEMENT. IN ADDITION, THE 0512000Z8 UW-CIMSS WATER
VAPOR/WIND SHEAR CHARTS INDICATE TC 05S (BILLY) IS UNDERGOING
MODERATE TO SEVERE UPPER LEVEL WIND SHEAR. INDEED, SATELLITE
ANALYSIS CONFIRMS THE LOW LEVEL CIRCULATION IS ALMOST TOTALLY
EXPOSED. SINCE THE CONVECTION HAS BLOWN AWAY FROM THE LOW LEVEL
CIRCULATION, TC 05S (BILLY) IS DISSIPATING RAPIDLY OVER WATER.
TROPICAL CYCLONE 05S (BILLY) WILL CONTINUE TO DISSIPATE UNTIL IT
STRIKES LAND BY THE 24 HOUR FORECAST POSITION. AT THAT TIME, TC 05S
(BILLY) WILL DISSIPATE OVER THE AUSTRALIAN MAINLAND. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 060000Z6 IS 12 FEET. NEXT WARNINGS AT
060900Z5 (DTG 060751Z9), 061500Z2 (DTG 061351Z6), 062100Z9
(DTG 061951Z2) AND 070300Z0 (DTG 070151Z4). REFER TO TROPICAL
CYCLONE 06S WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 981206 09:00z
SUBJ: TROPICAL CYCLONE WARNING
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 015
02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
060600Z2 --- NEAR 21.5S8 115.0E7
MOVEMENT PAST SIX HOURS - 180 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
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
REPEAT POSIT: NEAR 21.5S8 115.0E7
---
FORECASTS:
12 HRS, VALID AT:
061800Z5 --- 22.3S7 115.1E8
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 24 HR POSIT: 160 DEG/ 03 KTS
---
24 HRS, VALID AT:
070600Z3 --- 22.8S2 115.3E0
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
060900Z5 POSITION NEAR 21.7S0 115.0E7.
TROPICAL CYCLONE 05S (BILLY) HAS TRACKED SOUTHWARD AT 5 KNOTS
OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED UPON A
060530Z4 VISIBLE SATELLITE IMAGE AND IS CONSISTANT WITH AN
060018Z5 MICROWAVE IMAGE. THE WARNING INTENSITY IS BASED UPON
A SATELLITE CURRENT INTENSITY ESTIMATE OF 35 KNOTS. TROPICAL
CYCLONE 05S (BILLY) CONTINUES TO DISSIPATE OVER WATER AS IT
TRACKS SOUTHWARD OVER THE NORTHWESTERN COAST OF AUSTRALIA. THE
ANIMATED INFRARED, VISIBLE, AND WATER VAPOR SATELLITE IMAGERY
CONTINUE TO SHOW A RAPIDLY WEAKENING SYSTEM MOVING JUST OFF THE
COAST. THE 060000Z6 UW-CIMSS WIND SHEAR CHARTS SHOW MODERATE
TO SEVERE VERTICAL WIND SHEAR DIRECTLY OVER TC 05S (BILLY) AND
CONTINUING TO THE SOUTHEAST. DUE TO THE HIGH SHEAR ENVIRONMENT,
TC 05S (BILLY) CONTINUES TO RAPIDLY DISSIPATE OVER WATER AND
WILL CONTINUE TO DISSIPATE AS IT TRACKS OVER THE AUSTRALIAN
MAINLAND. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 060600Z2 IS 12
FEET. NEXT WARNINGS AT 061500Z2 (DTG 061351Z6), 062100Z9 (DTG
061951Z2) AND 070300Z0 (DTG 070151Z4). REFER TO TROPICAL
CYCLONE 06S WARNINGS (WTXS32 PGTW)FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS31 PGTW 981206 15:00z
1. TROPICAL CYCLONE 05S (BILLY) WARNING NR 016
02 ACTIVE TROPICAL CYCLONES IN SOUTHERN HEMISPHERE
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
061200Z9 --- NEAR 22.6S0 115.6E3
MOVEMENT PAST SIX HOURS - 150 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 LAND
REPEAT POSIT: 22.6S0 115.6E3
---
FORECASTS:
12 HRS, VALID AT:
070000Z7 --- 24.1S7 116.1E9
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
061500Z2 POSITION NEAR 23.0S5 115.7E4.
FINAL WARNING FOR TC 05S (BILLY). TC 05S MADE LANDFALL NEAR ONSLOW,
AUSTRALIA AROUND 060630Z5. SYNOPTIC DATA INDICATES MAX SUSTAINED
(ONE MINUTE AVERAGE) WINDS WERE 30KTS. TROPICAL CYCLONE 05S (BILLY)
HAS TRACKED SOUTH-SOUTHEASTWARD AT 11 KNOTS OVER THE PAST 6 HOURS.
TC 05S (BILLY) INCREASED FORWARD MOVEMENT AS IT BECAME SHEARED AND
NOW EXISTS AS A LOW-LEVEL FEATURE WITH ISOLATED CONVECTION.
THE WARNING POSITION AND INTENSITY (25KTS) ARE BASED UPON 061130Z1
INFRARED SATELLITE IMAGERY ANALYSIS TECHNIQUES AND SYNOPTIC DATA
INTERPRETATION. ANIMATED INFRARED SATELLITE IMAGERY SHOWS TROPICAL
CYCLONE 05S (BILLY) CONTINUES TO DISSIPATE AS IT TRACKS SOUTH-
SOUTHEASTWARD OVER NORTHWESTERN AUSTRALIA. THE REMNANTS OF TC 05S
(BILLY) SHOULD CONTINUE TO MOVE SOUTH-SOUTHEASTWARD WITH THE WEAK
LOW-LEVEL STEERING FLOW ASSOCIATED WITH THE HIGH PRESSURE RIDGE TO
THE SOUTHEAST. TC 05S HAS CONTINUED TO WEAKEN DUE TO MODERATE TO
STRONG VERTICAL WINDSHEAR AND LAND INTERACTION. THE COMBINATION OF
THIS WINDSHEAR AND LAND EFFECTS HAVE CAUSED TC 05S (BILLY) TO
DISSIPATE AS A SIGNIFICANT TROPICAL CYCLONE. 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. REFER TO TROPICAL CYCLONE 06S (NONAME)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
Tropical cyclone tracks developed by Michael Bath using operational warnings and advisories.
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Document: tropical_cyclone_billy_jtwc_advisories.htm
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