Tropical Cyclones [Index]

Tropical Cyclone HELEN [Australian Region][South Indian Ocean][South Pacific Ocean][Southern Hemisphere][Summaries and Track Data]

WTXS21 PGTW 20080103 15:30z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
090 NM EITHER SIDE OF A LINE FROM 14.2S 127.3E TO 13.8S 130.2E
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 25 TO 30 KNOTS. METSAT IM-
AGERY AT 031200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 14.2S 127.5E.  THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT
02 KNOTS.
2. REMARKS: AN AREA OF CONVECTION NEAR 14.2S 127.5E, APPROXIMATELY
220 NM WEST-SOUTHWEST OF DARWIN, AUSTRALIA, HAS PERSISTED OVER THE
LAST 24 HOURS. RECENT ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
AND THE WYNDHAM RADAR SHOW A BROAD AREA OF LOW LEVEL CYCLONIC
TURNING, CURRENTLY OVER LAND, HAS BEGUN TO CONSOLIDATE WITH A NEWLY
DEVELOPED CENTRAL DENSE OVERCAST FEATURE. A RECENT 85 GHZ SSMI
MICROWAVE IMAGE SHOWS CONVECTIVE BANDING TO THE SOUTH AND WEST WRAP-
PINGINTO THE LOW LEVEL CIRCULATION CENTER. UPPER LEVEL ANALYSIS
INDICATES THE DISTURBANCE IS UNDER MODERATE VERTICAL WIND SHEAR,
HOWEVER, GOOD EQUATORIAL OUTFLOW IS ENHANCING THE CONVECTION. THIS
DISTURBANCE HAS THE POTENTIAL TO DEVELOP INTO A SIGNIFICANT TROPICAL
CYCLONE AS IT TRACKS EAST INTO THE WARM WATERS OF THE TIMOR SEA.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 994 MB. DUE TO
THE CONVECTIVE CONSOLIDATION AND THE ANTICIPATED TRACK OVER WATER,
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED
BY 041530Z.//
=========================================================================
WTXS32 PGTW 20080103 21:00z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ:  TROPICAL CYCLONE 10S WARNING NR 001
RMKS/
REF/A/NAVPACMETOCCEN PEARL HARBOR HI/031521Z JAN 08//
AMPN/TROPICAL CYCLONE FORMATION ALERT//
   1. TROPICAL CYCLONE 10S WARNING NR 001
   02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   031800Z --- NEAR 14.0S 127.6E
     MOVEMENT PAST SIX HOURS - 025 DEGREES AT 02 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: 14.0S 127.6E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   040600Z --- 13.5S 129.3E
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            065 NM SOUTHWEST QUADRANT
                            065 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 080 DEG/ 10 KTS
    ---
   24 HRS, VALID AT:
   041800Z --- 13.1S 131.4E
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 36 HR POSIT: 100 DEG/ 12 KTS
    ---
   36 HRS, VALID AT:
   050600Z --- 13.4S 133.8E
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 48 HR POSIT: 110 DEG/ 14 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   051800Z --- 14.3S 136.6E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
REMARKS:
032100Z POSITION NEAR 13.9S 128.0E.
TROPICAL CYCLONE (TC) 10S LOCATED APPROXIMATELY 210 NM WEST-SOUTHWEST
OF DARWIN, AUSTRALIA HAS TRACKED NORTH-NORTHEASTWARD AT 02 KNOTS OVER
THE PAST 06 HOURS. IMAGERY FROM THE WYNDHAM RADAR INDICATES THE WELL-
DEFINED LOW LEVEL CIRCULATION CENTER (LLCC) HAS MOVED OFF THE COAST
AND INTO THE JOSEPH BONAPARTE GULF. ALSO, A 031442Z TRMM 85 GHZ
MICROWAVE PASS SHOWS CONVECTIVE BANDING WRAPPING INTO THE
LLCC. THE UPPER LEVEL ENVIRONMENT IS FAVORABLE FOR FURTHER DEVELO-
PMENT WITH ANTICYCLONIC TURNING SUPERIMPOSED OVER THE SURFACE
CIRCULATION. THE SUBTROPICAL RIDGE, WHICH HAD BEEN THE PREVIOUS
WESTWARD STEERING INFLUENCE HAS SINCE WEAKENED DUE TO AN ADVANCING
TROUGH, ALLOWING THE NEAR EQUATORIAL RIDGE NORTH OF THE STORM TO
BECOME THE PRIMARY STEERING INFLUENCE. THE STORM IS EXPECTED
TO INTENSIFY OVER WATER THROUGH TAU 12 BEFORE IT CROSSES BACK OVER
LAND. NEAR TAU 48 THE STORM IS FORECAST TO MOVE INTO THE
GULF OF CARPENTARIA AND DEEPEN ONCE AGAIN. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 031800Z IS 13 FEET. THIS WARNING SUPERSEDES AND CANCELS
REF A, NAVPACMETOCCEN 031521Z JAN 08 TROPICAL CYCLONE FORMATION
ALERT (WTXS21 PGTW 031530). NEXT WARNINGS AT 040900Z AND 042100Z.
REFER TO TROPICAL CYCLONE  09S (ELNUS) WARNINGS (WTXS31 PGTW)
FOR TWELVE-HOURLY UPDATES.
=========================================================================
WTXS31 PGTW 20080104 09:00z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 10S (HELEN) WARNING NR 002 
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO 
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE 
--- 
WARNING POSITION: 
040600Z --- NEAR 13.2S 128.9E 
MOVEMENT PAST SIX HOURS - 065 DEGREES AT 11 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 
WIND RADII VALID OVER OPEN WATER ONLY 
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 
055 NM SOUTHEAST QUADRANT 
070 NM SOUTHWEST QUADRANT 
060 NM NORTHWEST QUADRANT 
REPEAT POSIT: 13.2S 128.9E 
--- 
FORECASTS: 
12 HRS, VALID AT: 
041800Z --- 12.8S 131.2E 
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT 
WIND RADII VALID OVER OPEN WATER ONLY 
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND 
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT 
040 NM SOUTHEAST QUADRANT 
065 NM SOUTHWEST QUADRANT 
065 NM NORTHWEST QUADRANT 
VECTOR TO 24 HR POSIT: 090 DEG/ 15 KTS 
--- 
24 HRS, VALID AT: 
050600Z --- 12.8S 134.3E 
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT 
WIND RADII VALID OVER OPEN WATER ONLY 
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND 
VECTOR TO 36 HR POSIT: 100 DEG/ 16 KTS 
--- 
36 HRS, VALID AT: 
051800Z --- 13.3S 137.6E 
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT 
WIND RADII VALID OVER OPEN WATER ONLY 
VECTOR TO 48 HR POSIT: 115 DEG/ 16 KTS 
--- 
EXTENDED OUTLOOK: 
48 HRS, VALID AT: 
060600Z --- 14.5S 140.6E 
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT 
WIND RADII VALID OVER OPEN WATER ONLY 
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT 
060 NM SOUTHEAST QUADRANT 
055 NM SOUTHWEST QUADRANT 
070 NM NORTHWEST QUADRANT 
--- 
REMARKS: 
040900Z POSITION NEAR 13.1S 129.5E. 
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 040600Z IS 16 FEET. 
NEXT WARNINGS AT 042100Z AND 050900Z. 
REFER TO TROPICAL CYCLONE 09S (ELNUS) WARNINGS (WTXS32 PGTW) 
FOR TWELVE-HOURLY UPDATES. 
=========================================================================
WTXS31 PGTW 20080104 21:00z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 10S (HELEN) WARNING NR 003
   01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   041800Z --- NEAR 13.2S 131.1E
     MOVEMENT PAST SIX HOURS - 095 DEGREES AT 12 KTS
     POSITION ACCURATE TO WITHIN 040 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   REPEAT POSIT: 13.2S 131.1E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   050600Z --- 13.3S 134.0E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 24 HR POSIT: 100 DEG/ 15 KTS
    ---
   24 HRS, VALID AT:
   051800Z --- 13.7S 137.0E
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
                            070 NM SOUTHEAST QUADRANT
                            065 NM SOUTHWEST QUADRANT
                            075 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 105 DEG/ 14 KTS
    ---
   36 HRS, VALID AT:
   060600Z --- 14.4S 139.7E
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
                            080 NM SOUTHEAST QUADRANT
                            075 NM SOUTHWEST QUADRANT
                            085 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 115 DEG/ 13 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   061800Z --- 15.5S 142.2E
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
    ---
REMARKS:
042100Z POSITION NEAR 13.2S 131.8E.
TROPICAL CYCLONE (TC) 10S (HELEN), LOCATED APPROXIMATELY 45 NM SOUTH-
SOUTHEAST OF DARWIN, AUSTRALIA, HAS TRACKED EASTWARD AT 12 KNOTS OVER
THE PAST 06 HOURS. THE CURRENT STORM POSITION AND INTENSITY ARE BASED
ON DVORAK SATELLITE FIXES FORM PGTW AND ABRF, RADAR IMAGERY FROM
DARWIN, AND SYNOPTIC OBSERVATIONS FROM THE AREA AFFECTED BY THE STORM.
STRONG LOW TO MID-LEVEL WESTERLY FLOW ASSOCIATED WITH NEAR-EQUATORIAL
RIDGING TO THE NORTH OF THE STORM REMAINS THE PRIMARY STEERING INFLU-
ENCE. THIS STEERING RIDGE IS EXPECTED TO REMAIN IN PLACE THROUGH THE
FORECAST PERIOD, RESULTING IN A GENERALLY EASTWARD TO SOUTHEASTWARD
TRACK. TC 10S WILL WEAKEN OVER LAND BEFORE REEMERGING OVER WARM WATER
IN THE GULF OF CARPENTARIA AROUND TAU 18. THE STORM IS MOVING EAST OF
A SYNOPTIC-SCALE UPPER LEVEL ANTICYCLONE CENTER AND WILL EXPERIENCE
INCREASING WESTERLY VERTICAL WIND SHEAR AS A RESULT. PASSAGE OVER LAND
DURING THE NEXT 18 HOURS WILL LIKELY PREVENT THE STORM FROM DEVELOPING
A STRONG OUTFLOW BUFFER AGAINST THIS INCREASING VERTICAL WIND SHEAR.
THEREFORE, THE STORM IS EXPECTED TO INTENSIFY SLOWLY AS IT CROSSES
INTO THE GULF OF CARPENTARIA. THE SYSTEM WILL AGAIN MAKE LANDFALL OVER
THE CAPE YORK PENINSULA JUST PRIOR TO TAU 48 AND BEGIN DISSIPATING
THEREAFTER. THE AVAILABLE NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT
WITH BOTH THE TRACK AND INTENSITY FORECAST. NEXT WARNINGS AT 050900Z
AND 052100Z.//
=========================================================================
WTXS31 PGTW 20080105 09:00z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 10S (HELEN) WARNING NR 004
   01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   050600Z --- NEAR 13.6S 133.6E
     MOVEMENT PAST SIX HOURS - 105 DEGREES AT 13 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
   REPEAT POSIT: 13.6S 133.6E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   051800Z --- 13.6S 136.2E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 24 HR POSIT: 100 DEG/ 13 KTS
    ---
   24 HRS, VALID AT:
   060600Z --- 14.1S 138.9E
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
                            070 NM SOUTHEAST QUADRANT
                            065 NM SOUTHWEST QUADRANT
                            075 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 115 DEG/ 12 KTS
    ---
   36 HRS, VALID AT:
   061800Z --- 15.1S 141.2E
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
                            080 NM SOUTHEAST QUADRANT
                            075 NM SOUTHWEST QUADRANT
                            085 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 145 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   070600Z --- 16.6S 142.4E
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
    ---
REMARKS:
050900Z POSITION NEAR 13.6S 134.2E.
TROPICAL DEPRESSION (TD) 10S (HELEN) LOCATED APPROXIMATELY 180 NM
EAST-SOUTHEAST OF DARWIN, AUSTRALIA HAS TRACKED EAST-SOUTHEASTWARD
AT 13 KNOTS OVER THE PAST 06 HOURS. TD 10S HAS WEAKENED SIGNIFICANTLY
OVER THE PAST 12 HOURS AS IT CONTINUES TO TRACK OVER CENTRAL ARNHEM
LAND. THE SYSTEM IS EXPECTED TO CROSS INTO THE GULF OF CARPENTARIA
NEAR TAU 12, AND REINTENSIFY UNDER THE INFLUENCE OF HIGH SEA SURFACE
TEMPERATURES AND LOW TO MODERATE WIND SHEAR. AFTER CROSSING INTO THE
CAPE YORK PENINSULA THE SYSTEM WILL WEAKEN AND DISSIPATE. NEXT
WARNINGS AT 052100Z AND 060900Z.//
=========================================================================
WTPS31 PGTW 20080105 21:00z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//    
RMKS/    
1. TROPICAL CYCLONE 10S (HELEN) WARNING NR 005    
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   051800Z --- NEAR 13.5S 136.7E
     MOVEMENT PAST SIX HOURS - 090 DEGREES AT 17 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
   REPEAT POSIT: 13.5S 136.7E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   060600Z --- 13.9S 139.0E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   VECTOR TO 24 HR POSIT: 110 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   061800Z --- 14.6S 140.8E
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
                            070 NM SOUTHEAST QUADRANT
                            065 NM SOUTHWEST QUADRANT
                            070 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 125 DEG/ 07 KTS
    ---
   36 HRS, VALID AT:
   070600Z --- 15.4S 141.9E
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
   VECTOR TO 48 HR POSIT: 215 DEG/ 04 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   071800Z --- 16.0S 141.5E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
    ---
REMARKS:
052100Z POSITION NEAR 13.6S 137.3E.
TROPICAL CYCLONE (TC) 10S (HELEN), LOCATED APPROXIMATELY 345 NM EAST
OF DARWIN, AUSTRALIA, HAS TRACKED EASTWARD AT 17 KNOTS OVER THE PAST
06 HOURS. DVORAK SATELLITE FIXES FROM PGTW AND ADRM, RADAR IMAGERY
FROM GOVE, AUSTRALIA, AND SYNOPTIC OBSERVATIONS FROM THE AREA AFFECT-
ED BY THE STORM INDICATE THAT TC 10S HAS REEMERGED OVER WATER IN THE
NORTHWESTERN GULF OF CARPENTARIA DURING THE PAST 06 HOURS. THE WEAK-
ENED SYSTEM CONTINUES TO TRACK EASTWARD IN RESPONSE TO STRONG LOW TO
MID-LEVEL WESTERLY FLOW ASSOCIATED WITH NEAR-EQUATORIAL RIDGING TO
THE NORTH. WESTERLY TO NORTHWESTERLY STEERING FLOW IS EXPECTED TO
PERSIST THROUGH TAU 36, CARRYING THE STORM EASTWARD TOWARD THE CAPE
YORK PENINSULA. HOWEVER, FORWARD MOTION SHOULD SLOW IN THE NEAR TERM
AS THE SYSTEM BEGINS TO REORGANIZE OVER WATER AND LATER IN THE FORE-
CAST PERIOD AS A BUILDING SUBTROPICAL RIDGE TO THE SOUTH BEGINS TO
EXERT A COMPETING STEERING INFLUENCE. BY TAU 48, SUBTROPICAL RIDGING
WILL BECOME WELL-ESTABLISHED, AND IS EXPECTED TO TURN THE STORM WEST-
WARD AFTER A BRIEF PERIOD OF QUASISTATIONARY MOTION. THE EXACT STORM
TRACK DEPENDS ON HOW QUICKLY THE SUBTROPICAL STEERING RIDGE TO THE
SOUTH DEVELOPS AND BEGINS TO INFLUENCE THE STORM. IF THIS RIDGE
DEVELOPS QUICKLY, THE STORM MAY REMAIN OVER THE GULF OF CARPENTARIA,
TURNING WESTWARD BEFORE MAKING LANDFALL IN THE CAPE YORK PENINSULA.
TC 10S IS FORECASTED TO INTENSIFY SLOWLY OVER THE NEXT 24 HOURS AS
THE SYSTEM STRUGGLES TO REORGANIZE UNDER THE COMPETING INFLUENCES OF
FAVORABLE DIFFLUENCE ALOFT AND MODERATE TO HIGH OCEAN HEAT CONTENT
AND UNFAVORABLE WESTERLY VERTICAL WIND SHEAR. THE STORM MAY EXPERI-
ENCE A BRIEF PERIOD OF MORE RAPID INTENSIFICATION BEFORE MAKING
LANDFALL IN THE CAPE YORK PENINSULA AS IT PASSES OVER AN AREA OF
HIGH OCEAN HEAT CONTENT OBSERVED NEAR THE COAST. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 051800Z IS 10 FEET. NEXT WARNINGS AT 060900Z AND
062100Z.//
=========================================================================
WTPS31 PGTW 20080106 09:00z
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 10S (HELEN) WARNING NR 006
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   060600Z --- NEAR 13.6S 140.1E
     MOVEMENT PAST SIX HOURS - 100 DEGREES AT 16 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
   REPEAT POSIT: 13.6S 140.1E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   061800Z --- 14.5S 142.1E
   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: 150 DEG/ 06 KTS
    ---
   24 HRS, VALID AT:
   070600Z --- 15.6S 142.7E
   MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
    ---
REMARKS:
060900Z POSITION NEAR 13.8S 140.6E.
TROPICAL CYCLONE (TC) 10S (HELEN) LOCATED APPROXIMATELY 380 NM WEST-
NORTHWEST OF CAIRNS, AUSTRALIA, HAS TRACKED EASTWARD AT 16 KNOTS
OVER THE PAST 06 HOURS. TC 10S HAS CONTINUED TO TRACK ACROSS THE
GULF OF CARPENTARIA. THE LOW LEVEL CIRCULATION CENTER (LLCC) HAS
REMAINED BROAD AFTER CROSSING INTO THE GULF, AND IS NOT ANTICIPATED
TO CONSOLIDATE PRIOR TO MAKING LANDFALL IN CAPE YORK NEAR TAU 12.
THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON
WARNING CENTER (NAVPACMETOCCEN).  THE SYSTEM WILL BE CLOSELY MON-
ITORED FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
060600Z IS 10 FEET.//