Updated: 17 June 2020
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| Tropical Cyclones
[Index] | Tropical Cyclone ALESSIA : JTWC Advisories |
| Season 2013-2014 Summaries (Operational Data): [AU] [SIO] [SPAC] [SH] | |
| ---> Tropical Cyclone ALESSIA Track Map and Data |
WTXS21 PGTW 20131121 23:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN 170
NM EITHER SIDE OF A LINE FROM 13.5S 117.5E TO 14.0S 123.8E 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 IMAGERY AT 212130Z
INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 13.6S 118.2E. THE
SYSTEM IS MOVING EAST-SOUTHEASTWARD AT 08 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.6S
118.2E, IS NOW LOCATED NEAR 13.7S 118.5E, APPROXIMATELY 330 NM
NORTHWEST OF BROOME, AUSTRALIA. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS PERSISTENT DEEP CONVECTION OVER A DEVELOPING LOW
LEVEL CIRCULATION CENTER (LLCC). A RECENT 211400Z METOP-B 89 GHZ
MICROWAVE PASS SHOWS THE LLCC HAS BECOME MORE SYMMETRIC OVER THE
PAST 24 HOURS, BUT INDICATES DEEP CONVECTION REMAINS ALONG THE
SOUTHERN PERIPHERY UNDER THE INFLUENCE OF MODERATE LEVELS OF
VERTICAL WIND SHEAR (15 TO 20 KNOTS). SEA SURFACE TEMPERATURES ARE
FAVORABLE FOR DEVELOPMENT, RANGING FROM 29 TO 31 DEGREES CELSIUS.
MOST MODELS MAINTAIN A WEAK CIRCULATION, WHICH TRAVERSES NORTHERN
AUSTRALIA OVER THE NEXT SEVERAL DAYS BUT DO NOT INDICATE STRONG
DEVELOPMENT IN THE NEAR-TERM. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 28 TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1003 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
222300Z.//
=========================================================================
WTXS31 PGTW 20131122 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (TWO) WARNING NR 001//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/212251ZNOV2013//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. TROPICAL CYCLONE 02S (TWO) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
220600Z --- NEAR 14.5S 120.1E
MOVEMENT PAST SIX HOURS - 120 DEGREES AT 14 KTS
POSITION ACCURATE TO WITHIN 040 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: 14.5S 120.1E
---
FORECASTS:
12 HRS, VALID AT:
221800Z --- 14.7S 121.7E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 090 DEG/ 08 KTS
---
24 HRS, VALID AT:
230600Z --- 14.7S 123.4E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 080 DEG/ 09 KTS
---
36 HRS, VALID AT:
231800Z --- 14.3S 125.3E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 080 DEG/ 10 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
240600Z --- 13.9S 127.3E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 72 HR POSIT: 085 DEG/ 08 KTS
---
72 HRS, VALID AT:
250600Z --- 13.5S 130.7E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 96 HR POSIT: 100 DEG/ 08 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
260600Z --- 13.9S 133.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 120 HR POSIT: 135 DEG/ 04 KTS
---
120 HRS, VALID AT:
270600Z --- 15.1S 135.1E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
220900Z POSITION NEAR 14.5S 120.5E.
TROPICAL CYCLONE 02S (TWO), LOCATED APPROXIMATELY 237 NM NORTH-
NORTHWESTWARD OF BROOME, AUSTRALIA, HAS TRACKED EAST-SOUTHEASTWARD AT
14 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS THE SYSTEM HAS SIGNIFICANTLY DEEPENED AS FORMATIVE
BANDS WRAPPED TIGHTER INTO THE LOW LEVEL CIRCULATION CENTER THAT HAS
BECOME BETTER-DEFINED. THE INITIAL POSITION AND INTENSITY ARE BASED
ON CLOSELY-SPACED DVORAK FIXES FROM PGTW, APRF, AND KNES. UPPER LEVEL
ANALYSIS INDICATES THE SYSTEM IS UNDER THE RIDGE AXIS IN AN AREA OF
LOW (05-10 KNOT) VERTICAL WIND SHEAR AND GOOD RADIAL OUTFLOW. THE
CYCLONE IS TRACKING ALONG THE OUTER BOUNDARY OF A NEAR-EQUATORIAL
RIDGE TO THE NORTHEAST AND IS EXPECTED TO MOVE ON A GENERALLY
EASTWARD PATTERN TOWARDS DARWIN. THE SYSTEM WILL CONTINUE TO
INTENSIFY OVER THE NEXT 36 HOURS AS UPPER LEVEL CONDITIONS, IN
ADDITION TO WARM SEA SURFACE TEMPERATURES, PREVAIL. AFTERWARDS, THE
CYCLONE WILL DRAG ACROSS THE SWAMPY TERRAIN OF NORTHERN AUSTRALIA
JUST SOUTH OF DARWIN. INTERACTION WITH THE LANDMASS WILL CAUSE ITS
GRADUAL DECAY AND EVENTUAL DISSIPATION BY TAU 120. THE AVAILABLE
NUMERIC GUIDANCE IS IN FAIR AGREEMENT; HOWEVER, GIVEN THE UNCERTAINTY
OF AN OVER LAND TRACK, THERE IS LOW CONFIDENCE IN THE JTWC TRACK
FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 220600Z IS 10 FEET. NEXT
WARNINGS AT 222100Z AND 230900Z. THIS WARNING SUPERSEDES AND CANCELS
REF A (WTXS21 PGTW 212300). //
=========================================================================
WTXS31 PGTW 20131122 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 02S (ALESSIA) 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:
221800Z --- NEAR 14.7S 122.8E
MOVEMENT PAST SIX HOURS - 100 DEGREES AT 12 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 - 055 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.7S 122.8E
---
FORECASTS:
12 HRS, VALID AT:
230600Z --- 14.7S 124.4E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 080 DEG/ 09 KTS
---
24 HRS, VALID AT:
231800Z --- 14.3S 126.3E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 080 DEG/ 10 KTS
---
36 HRS, VALID AT:
240600Z --- 13.9S 128.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 085 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
241800Z --- 13.7S 130.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 72 HR POSIT: 100 DEG/ 06 KTS
---
72 HRS, VALID AT:
251800Z --- 14.0S 132.4E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 96 HR POSIT: 105 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
261800Z --- 14.6S 134.6E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
222100Z POSITION NEAR 14.7S 123.2E.
TROPICAL CYCLONE (TC) 02S (ALESSIA), LOCATED APPROXIMATELY 490 NM
WEST-SOUTHWESTWARD OF DARWIN, AUSTRALIA, HAS TRACKED EASTWARD AT 12
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED IMAGERY
DEPICTS A CONSOLIDATING SYSTEM WITH A COMPACT AREA OF DEEP
CONVECTION PERSISTING OVER THE LOW-LEVEL CIRCULATION CENTER (LLCC).
A PARTIAL 221513Z TRMM 37 GHZ IMAGE AND A PARTIAL 221837Z AMSU-B 89
GHZ IMAGE DEPICT CURVED CONVECTIVE BANDING WRAPPING INTO THE CENTER,
PROVIDING GOOD CONFIDENCE IN THE INITIAL POSITION. THE INITIAL
INTENSITY IS ASSESSED AT 45 KNOTS BASED ON CURRENT INTENSITY
ESTIMATES OF 45 KNOTS FROM ALL AGENCIES. TC 02S IS TRACKING ALONG
THE SOUTHERN PERIPHERY OF THE NEAR-EQUATORIAL RIDGE AND IS FORECAST
TO CONTINUE TRACKING GENERALLY EASTWARD THROUGH THE FORECAST PERIOD.
TC 02S IS EXPECTED TO SKIRT THE NORTHERN COAST OF AUSTRALIA THROUGH
TAU 36 AND WILL MAKE LANDFALL NEAR TAU 48. TC ALESSIA IS EXPECTED TO
INTENSIFY SLIGHTLY TO A PEAK OF 50 KNOTS BY TAU 12 BUT SHOULD WEAKEN
THEREAFTER DUE TO LAND INTERACTION AND DRY AIR INTRUSION. DYNAMIC
MODEL GUIDANCE IS IN FAIR AGREEMENT BUT DIFFER ON THE STRENGTH AND
TIMING OF A DEVELOPING HIGH OVER EASTERN AUSTRALIA, WHICH WILL ACT
TO SLOW THE SYSTEM AND TURN IT EQUATORWARD. THE JTWC FORECAST FAVORS
THE GFS AND ECMWF SOLUTIONS, WHICH INDICATE A TURN SOUTHWARD NEAR
THE WESTERN GULF OF CARPENTARIA AFTER TAU 72. DUE TO THE DEVELOPING
HIGH AND PERSISTENT LAND INTERACTION, REGENERATION OVER THE GULF OF
CARPENTARIA IS UNLIKELY. OVERALL, THERE IS LOW CONFIDENCE IN THE
JTWC FORECAST DUE THE SHARP DIFFERENCES IN THE SOUTHWARD TRACK AFTER
TAU 48. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 221800Z IS 12 FEET. NEXT
WARNINGS AT 230900Z AND 232100Z.//
=========================================================================
WTXS31 PGTW 20131123 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 02S (ALESSIA) 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:
230600Z --- NEAR 14.9S 124.7E
MOVEMENT PAST SIX HOURS - 105 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 020 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 - 055 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.9S 124.7E
---
FORECASTS:
12 HRS, VALID AT:
231800Z --- 14.7S 126.4E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 080 DEG/ 09 KTS
---
24 HRS, VALID AT:
240600Z --- 14.4S 128.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 090 DEG/ 08 KTS
---
36 HRS, VALID AT:
241800Z --- 14.4S 130.0E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 48 HR POSIT: 095 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
250600Z --- 14.5S 131.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 72 HR POSIT: 115 DEG/ 05 KTS
---
72 HRS, VALID AT:
260600Z --- 15.4S 133.3E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
230900Z POSITION NEAR 14.9S 125.1E.
TROPICAL CYCLONE 02S (ALESSIA), LOCATED APPROXIMATELY 389 NM WEST-
SOUTHWESTWARD OF DARWIN, AUSTRALIA, HAS TRACKED EAST-SOUTHEASTWARD AT
09 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS THE SYSTEM HAS MAINTAINED OVERALL DEPTH AND FORMATIVE
STRUCTURE AS IT IS ABOUT TO MAKE LANDFALL INTO NORTHWEST AUSTRALIA.
THE INITIAL POSITION IS BASED ON THE ABOVE ANIMATION WITH FAIR
CONFIDENCE. THE INITIAL INTENSITY IS BASED ON CONGRUENT DVORAK
ESTIMATES FROM ALL REPORTING AGENCIES. STEERED BY THE NEAR-
EQUATORIAL RIDGE, TC ALESSIA IS EXPECTED TO GRADUALLY WEAKEN AND DRAG
EASTWARD INTO THE NORTHERN TERRITORY WITH A BRIEF WATER PASSAGE OVER
JOSEPH BONAPARTE GULF. AFTER TAU 48, A BUILDING HIGH OVER
EAST-CENTRAL AUSTRALIA WILL DEFLECT A WEAKENED 02S POLEWARD,
EVENTUALLY DISSIPATING BY TAU 72. OVERALL, THERE IS LOW CONFIDENCE IN
THE JTWC FORECAST DUE THE SHARP DIFFERENCES IN THE NUMERIC MODELS
SOUTHWARD TRACK AFTER TAU 48.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 230600Z IS 13 FEET. NEXT WARNINGS
AT 232100Z AND 240900Z. //
=========================================================================
WTXS31 PGTW 20131123 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
231800Z --- NEAR 14.0S 126.7E
MOVEMENT PAST SIX HOURS - 070 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.0S 126.7E
---
FORECASTS:
12 HRS, VALID AT:
240600Z --- 13.7S 128.5E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 090 DEG/ 09 KTS
---
24 HRS, VALID AT:
241800Z --- 13.7S 130.4E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 100 DEG/ 08 KTS
---
36 HRS, VALID AT:
250600Z --- 13.9S 132.0E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 105 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
251800Z --- 14.3S 133.5E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
232100Z POSITION NEAR 13.9S 127.2E.
TROPICAL CYCLONE (TC) 02S (ALESSIA), LOCATED APPROXIMATELY 261 NM
WEST-SOUTHWEST OF DARWIN, AUSTRALIA, HAS TRACKED EAST-NORTHEASTWARD
AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
(EIR) SATELLITE IMAGERY INDICATES INCREASING DEEP CONVECTION OVER
THE NORTHERN SEMI-CIRCLE OF TC 02S, WHICH IS TRACKING ALONG THE
NORTHERN KIMBERLY COAST. A 231613Z GCOM IMAGE DEPICTS A CURVED DEEP
CONVECTIVE BAND WRAPPING INTO THE NORTHEAST QUADRANT OF THE LOW-
LEVEL CIRCULATION CENTER (LLCC). A RECENT 231418Z TRMM IMAGE SHOWING
A DEFINED LLCC ALSO SUPPORTS THE CURRENT POSITION AND RECENT MOTION
WITH GOOD CONFIDENCE. TC 02S TRACKED JUST SOUTH OF TROUGHTON ISLAND
AND IS CURRENTLY LOCATED ABOUT 10 NM TO THE SOUTHEAST; SUSTAINED
SURFACE WINDS (10-MIN AVERAGE) PEAKED AT 37 KNOTS (SOUTHWESTERLY)
WITH A MINIMUM SLP OF 1001 MB REPORTED AT 23/17Z. THIS OBSERVATION
ALONG WITH DVORAK INTENSITY ESTIMATES SUPPORTS THE CURRENT INTENSITY
OF 40 KNOTS. TC 02S IS TRACKING ALONG THE SOUTHERN PERIPHERY OF THE
NEAR-EQUATORIAL RIDGE AND IS FORECAST TO CONTINUE TRACKING GENERALLY
EASTWARD THROUGH THE FORECAST PERIOD. DYNAMIC MODEL GUIDANCE IS IN
FAIR AGREEMENT BUT DIFFER ON THE STRENGTH AND TIMING OF A DEVELOPING
HIGH OVER EASTERN AUSTRALIA, WHICH WILL ACT TO SLOW THE SYSTEM AND
TURN IT POLEWARD. THE JTWC FORECAST FAVORS THE GFS AND ECMWF
SOLUTIONS, WHICH INDICATE A TURN SOUTHWARD NEAR THE WESTERN GULF OF
CARPENTARIA AFTER TAU 48. DUE TO THE DEVELOPING HIGH AND PERSISTENT
LAND INTERACTION, REGENERATION OVER THE GULF OF CARPENTARIA IS
UNLIKELY. OVERALL, THERE IS LOW CONFIDENCE IN THE JTWC FORECAST DUE
THE SHARP DIFFERENCES IN THE MODELS AFTER TAU 36. TC 02S IS EXPECTED
TO WEAKEN AND DISSIPATE OVER LAND BY TAU 48. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 231800Z IS 11 FEET. NEXT WARNINGS AT 240900Z AND
242100Z.//
=========================================================================
WTXS31 PGTW 20131124 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 005
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
240600Z --- NEAR 13.8S 129.0E
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 15 KTS
POSITION ACCURATE TO WITHIN 020 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: 13.8S 129.0E
---
FORECASTS:
12 HRS, VALID AT:
241800Z --- 13.9S 131.0E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 24 HR POSIT: 110 DEG/ 08 KTS
---
24 HRS, VALID AT:
250600Z --- 14.5S 132.6E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
240900Z POSITION NEAR 13.8S 129.5E.
TROPICAL CYCLONE 02S (ALESSIA), LOCATED APPROXIMATELY 136 NM
SOUTHWEST OF DARWIN, AUSTRALIA, HAS TRACKED EASTWARD AT 15 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS
THE SYSTEM HAS ACCELERATED ACROSS THE JOSEPH BONAPARTE GULF AS IT
MAINTAINED SYMMETRY. HOWEVER, THE CONVECTION HAS WEAKENED AS IT
APPROACHES THE NORTHERN TERRITORY SOUTH OF DARWIN TO MAKE ONE FINAL
LANDFALL BEOFRE TAU 12. THE INITIAL POSITION IS BASED ON THE ABOVE
ANIMATION WITH HIGH CONFIDENCE. THE INITIAL INTENSITY IS SUPPORTED BY
DVORAK ESTIMATES FROM PGTW, KNES, AND APRF. TC ALESSIA IS EXPECTED TO
QUICKLY DISSIPATE AFTER LANDFALL DUE TO FRICTIONAL EFFECTS. 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 240600Z IS 11
FEET. //
=========================================================================
WTPS21 PGTW 20131127 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 100 NM RADIUS OF 15.6S 137.0E 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 270230Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 15.6S 137.0E. THE SYSTEM IS
MOVING SOUTHWARD AT 02 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 15.3S
136.7E IS NOW LOCATED NEAR 15.6N 137.0E, APPROXIMATELY 185 NM SOUTH
OF GOVE, AUSTRALIA. RECENT MULTISPECTRAL SATELLITE IMAGERY SHOWS DEEP
CONVECTIVE BANDING PERSISTING OVER AN INCREASINGLY DEFINED LOW LEVEL
CIRCULATION CENTER, WHICH IS ALSO EVIDENT IN RADAR DATA FROM
MORNINGTON ISLAND. NEARBY SYNOPTIC OBSERVATIONS INDICATE SEA LEVEL
PRESSURE NEAR 999 MB AND SUSTAINED WINDS, OUTSIDE OF THE DEEP
CONVECTIVE BANDS, OF ABOUT 30 KNOTS. THE UPPER LEVEL ENVIRONMENT IS
FAVORABLE FOR FURTHER DEVELOPMENT, WITH LOW VERTICAL WIND SHEAR AND
STRONG EASTWARD AND POLEWARD OUTFLOW ALOFT. THE CIRCULATION CENTER IS
CLOSE TO LAND, AND MAY TRACK INLAND BEFORE THIS DISTURBANCE
CONSOLIDATES INTO A TROPICAL CYCLONE. MAXIMUM SUSTAINED SURFACE WINDS
ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 999 MB. BASED ON IMPROVING ORGANIZATION AND
FAVORABLE UPPER LEVEL CONDITIONS, 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 280300Z.//
=========================================================================
WTPS31 PGTW 20131127 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 006
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
270600Z --- NEAR 15.8S 137.6E
MOVEMENT PAST SIX HOURS - 110 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 030 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: 15.8S 137.6E
---
FORECASTS:
12 HRS, VALID AT:
271800Z --- 16.2S 138.2E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 150 DEG/ 03 KTS
---
24 HRS, VALID AT:
280600Z --- 16.7S 138.5E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 160 DEG/ 04 KTS
---
36 HRS, VALID AT:
281800Z --- 17.5S 138.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 165 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
290600Z --- 18.3S 139.0E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
270900Z POSITION NEAR 15.9S 137.7E.
TROPICAL CYCLONE 02S (ALESSIA), LOCATED APPROXIMATELY 105 NM WEST-
NORTHWEST OF MORNINGTON ISLAND, AUSTRALIA, HAS TRACKED EAST-
SOUTHEASTWARD AT 03 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) IN CONJUNCTION WITH RADAR
IMAGERY FROM MORNINGTON ISLAND SHOWS A WELL DEFINED LOW LEVEL
CIRCULATION CENTER (LLCC) HAS REDEVELOPED OVER THE GULF OF
CARPENTARIA. CURRENT DVORAK ESTIMATES INDICATE THE SYSTEM HAS
REACHED 35 KNOTS, CONSTITUTING THE RE-ISSUANCE OF WARNINGS. UPPER
LEVEL ANALYSIS INDICATES AN ANTICYCLONE OVER THE NORTHERN TERRITORY
IS PROVIDING RADIAL OUTFLOW AND MODERATE LEVELS OF VERTICAL WIND
SHEAR NEAR THE LLCC. SEA SURFACE TEMPERATURES IN THE GULF OF
CARPENTARIA ARE VERY FAVORABLE FOR FURTHER DEVELOPMENT, BUT MODEL
GUIDANCE AND THE MSI INDICATE THIS SYSTEM WILL BE SHORT-LIVED AS IT
TRACKS ALONG THE COAST, EVENTUALLY MOVING OVER LAND IN THE NEXT 24
HOURS. DUE TO POOR CONSISTENCY IN THE AVAILABLE MODEL GUIDANCE THERE
IS LOW CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 270600Z IS 8 FEET. NEXT WARNINGS AT 272100Z AND 280900Z.//
=========================================================================
WTPS31 PGTW 20131127 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 02S (ALESSIA) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
271800Z --- NEAR 16.5S 137.7E
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE, RADAR AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
REPEAT POSIT: 16.5S 137.7E
---
FORECASTS:
12 HRS, VALID AT:
280600Z --- 16.7S 137.0E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
272100Z POSITION NEAR 16.6S 137.5E.
TROPICAL CYCLONE (TC) 02S (ALESSIA), LOCATED APPROXIMATELY 462 NM
EAST-SOUTHEAST OF DARWIN, AUSTRALIA, HAS TRACKED SOUTHWARD AT 03
KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY
DEPICTS PERSISTENT DEEP CONVECTION OVER THE EASTERN SEMI-CIRCLE OF
A POORLY-DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC). RADAR IMAGERY
FROM MORNINGTON ISLAND INDICATES THAT THE LLCC HAS TRACKED BACK OVER
LAND AND HAS WEAKENED SIGNIFICANTLY. A 271242Z ASCAT IMAGE SHOWS
ONLY 15 TO 25 KNOT WINDS OVER THE EASTERN SEMI-CIRCLE. SURFACE
OBSERVATIONS LOCATED OVER THE WESTERN SEMI-CIRCLE OF THE SYSTEM
INDICATE SUSTAINED WINDS LESS THAN 10 KNOTS AND SLP NEAR 1003 MB.
THE INITIAL POSITION IS BASED ON RADAR IMAGERY WITH LOW CONFIDENCE
DUE TO THE LACK OF CONVECTIVE BANDING INTO THE CENTER. THE INITIAL
INTENSITY IS ASSESSED AT 30 KNOTS AND IS BASED ON THE ASCAT DATA.
TC 02S IS DRIFTING SOUTHWARD AND IS EXPECTED TO REMAIN OVER LAND AS
IT TRACKS WESTWARD UNDER THE LOW-LEVEL SUBTROPICAL RIDGE POSITIONED
TO THE SOUTH. DYNAMIC MODELS INDICATE SLOW TRACK SPEEDS AND A
GENERALLY WESTWARD TRACK WITH A LOW PROBABILITY OF TRACKING BACK
OVER THE GULF OF CARPENTARIA. OVERALL, THERE IS LOW CONFIDENCE IN THE
JTWC FORECAST TRACK DUE TO THE LACK OF CONVECTIVE STRUCTURE AND
WEAK STEERING ENVIRONMENT. 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.//
Tropical cyclone tracks developed by Michael Bath using operational warnings and advisories.
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Document: tropical_cyclone_alessia_jtwc_advisories.htm
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