SIO: 18S - Remnants

[supercane4867]

12.5S 102.2E

[Grifforzer]

Tropical Cyclone Three Day Outlook for the Western Region
Issued at 1:23 pm WST on Wednesday 20 February 2013
for the period until midnight WST Saturday 23 February 2013.

A weak low is located in the monsoon trough near 14S 106E, about 400km
south of Christmas Island. The low is moving slowly westwards and may develop
into a tropical cyclone on Saturday.

Likelihood of this system being a tropical cyclone in the Western Region on:
Thursday Low
Friday Low
Saturday Moderate

[Grifforzer]

A weak low [11U] is located in the monsoon trough near 13S 104E, about 460km
south of Christmas Island. The low is moving slowly westwards and may develop
into a tropical cyclone on Saturday or Sunday. This system is expected to pass
to the south of Cocos Island. A direct impact is not expected, but it may cause
squally winds and heavy rainfall over the weekend.

Likelihood of this system being a tropical cyclone in the Western Region on:
Friday Low
Saturday Moderate
Sunday High

[Hurricane_Luis]

Invest 96S (Tropical Low 11U)

[/URL]

[Grifforzer]

A low [11U] is located in the monsoon trough near 14S 101E at midday WST, about 500 km east southeast of Cocos Island. The low is moving slowly westwards and may develop into a tropical cyclone on Sunday or Monday.

This system is expected to pass just south of Cocos Island on Sunday and cause squally winds and heavy rainfall over the weekend.

Tropical Cyclone Formation Potential
=====================================
Saturday: Low
Sunday: Moderate
Monday: High

[euro6208]

AN AREA OF CONVECTION HAS PERSISTED NEAR 14.6S 101.3E,
APPROXIMATELY 295 NM EAST-SOUTHEAST OF COCOS ISLAND, AUSTRALIA.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS A WEAK LOW LEVEL
CIRCULATION WITH FLARING CONVECTION DISPLACED TO THE SOUTHWEST. UPPER
LEVEL ANALYSIS INDICATES THE CYCLONE IS WELL TO THE NORTH OF A RIDGE
AXIS IN AN AREA OF STRONG 30-KNOT VERTICAL WIND SHEAR. NUMERIC MODELS
INCLUDING NOGAPS, ECMWF, AND GFS ARE DEVELOPING THIS SYSTEM IN 36-48
HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 MB.
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS LOW.

[euro6208]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.8S
100.6E, IS NOW LOCATED NEAR 13.1S 99.6E, APPROXIMATELY 170 NM EAST-
SOUTHEAST OF COCOS ISLAND, AUSTRALIA. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY (MSI) INDICATES A BROAD AND ELONGATED LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH FRAGMENTED DEEP CONVECTION OVER THE
WESTERN SEMI-CIRCLE, WHICH IS READILY EVIDENT IN A 230142Z SSMIS
MICROWAVE IMAGE. A 230223Z ASCAT IMAGE SHOWED AN ELONGATED
CIRCULATION WITH 25 TO 30 KNOT WINDS OVER THE WESTERN SEMI-CIRCLE
AND 10 TO 20 KNOT WINDS OVER THE EASTERN SEMI-CIRCLE. UPPER-LEVEL
ANALYSIS INDICATES THAT THE LLCC IS LOCATED JUST EQUATORWARD OF THE
SUBTROPICAL RIDGE AXIS AND IS UNDER MODERATE (15 TO 20 KNOTS)
VERTICAL WIND SHEAR WITH GOOD POLEWARD OUTFLOW. DYNAMIC MODELS
INDICATE SLOW DEVELOPMENT OVER THE NEXT TWO DAYS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS REMAINS MEDIUM.

[mrbagyo]

exposed..

[euro6208]

WTXS33 PGTW 251500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 003
03 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
251200Z --- NEAR 14.6S 98.9E
MOVEMENT PAST SIX HOURS - 140 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 050 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: 14.6S 98.9E
---
FORECASTS:
12 HRS, VALID AT:
260000Z --- 14.9S 99.2E
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: 125 DEG/ 02 KTS
---
24 HRS, VALID AT:
261200Z --- 15.1S 99.5E
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 36 HR POSIT: 100 DEG/ 02 KTS
---
36 HRS, VALID AT:
270000Z --- 15.2S 100.0E
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 48 HR POSIT: 090 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
271200Z --- 15.2S 100.6E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 095 DEG/ 03 KTS
---
72 HRS, VALID AT:
281200Z --- 15.3S 101.7E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 095 DEG/ 09 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
011200Z --- 15.6S 105.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 105 DEG/ 10 KTS
---
120 HRS, VALID AT:
021200Z --- 16.6S 109.7E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
251500Z POSITION NEAR 14.7S 99.0E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 980 NM
WEST-NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHEASTWARD AT
06 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY
SHOWS THE MAIN CONVECTION CONTINUES TO BE SHEARED WESTWARD, FULLY
EXPOSING A LOW LEVEL CIRCULATION CENTER THAT APPEARS TO HAVE SLIGHTLY
UNRAVELED. THE INITIAL POSITION IS BASED ON THE ABOVE ANIMATION AND
THE INITIAL INTENSITY IS BASED ON THE HIGH END OF DVORAK ESTIMATES
FROM PGTW, KNES, AND APRF. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM
IS WELL TO THE NORTH OF THE RIDGE AXIS IN AN AREA OF MODERATE TO
STRONG (20-30 KNOT) EASTERLY VERTICAL WIND SHEAR (VWS). THE CYCLONE
IS TRACKING ALONG THE SOUTHERN PERIPHERY OF THE NEAR-EQUATORIAL RIDGE
TO THE NORTH AND IS EXPECTED TO REMAIN ON THIS TRACK THROUGHOUT THE
FORECAST PERIOD. TC 18S WILL CONTINUE TO STRUGGLE OVER THE NEXT TWO
DAYS AS STRONG VWS WILL PERSIST. AFTER TAU 48, THE SYSTEM WILL BEGIN
TO INTENSIFY AS THE VWS DECREASES AS THE RIDGE TO THE SOUTH IS
WEAKENED BY THE APPROACH OF A MID-LATITUDE TROUGH. THE AVAILABLE
NUMERICAL GUIDANCE IS IN OVERALL AGREEMENT WITH AN EASTWARD
PROGRESSION OF THE CYCLONE; HOWEVER, THERE ARE SIGNIFICANT
DIFFERENCES AMONG THE MEMBERS IN TRACK SPEED WITH GFDN THE FASTEST
AND WBAR THE SLOWEST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 251200Z IS
12 FEET. NEXT WARNINGS AT 260300Z AND 261500Z. REFER TO TROPICAL
CYCLONE 17S (RUSTY) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.
//
NNNN

[supercane4867]

It was upgraded to Cyclone 18S but got sheared back to an invest



TPXS12 PGTW 281807
A. REMNANTS OF TROPICAL CYCLONE 18S (SE OF COCOS IS)
B. 28/1732Z
C. 14.2S
D. 101.7E
E. FIVE/MTSAT
F. T1.0/1.0/D1.0/24HRS STT: D1.0/06HRS
G. IR/EIR
H. REMARKS: 47A/PBO PTLY XPSD LLCC/ANMTN. CNVCTN WRAP OF .20 ON
LOG10 SPIRAL YIELDS A DT OF 1.0. PT AND MET AGREE. DBO DT.
I. ADDITIONAL POSITIONS:
28/1318Z 14.5S 101.2E SSMS
28/1450Z 14.4S 101.2E MMHS

UEHARA