SIO: DONGO - Extratropical: Discussion

[Crostorm]

Come on Billy

[HURAKAN]

Still ex-Billy

[Crostorm]

[Crostorm]

[HURAKAN]

Doesn't give up.

[RattleMan]

ABIO10 PGTW 080300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE INDIAN
/OCEAN REISSUED/080300Z-081800ZJAN2009//
RMKS/
1. NORTH INDIAN OCEAN AREA (MALAY PENINSULA WEST TO COAST OF AFRICA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
2. SOUTH INDIAN OCEAN AREA (135E WEST TO COAST OF AFRICA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION ASSOCIATED WITH THE REMNANT CIRCULA-
TION OF TROPICAL CYCLONE 05S HAS PERSISTED NEAR 15.1S 66.5E, APPROX-
IMATELY 725 NM EAST-NORTHEAST OF LA REUNION. RECENT ANTIMATED WATER
VAPOR AND INFRARED SATELLITE IMAGERY SHOWS DEEP CONVECTION FLARING
ON THE NORTHEASTERN PERIPHERY OF A BROAD LOW LEVEL CIRCULATION CENTER
(LLCC) EVIDENT IN A PARTIAL 072126Z AMSR-E PASS. THE LLCC LIES NORTH
OF AN UPPER LEVEL RIDGE AXIS IN AN AREA OF MODERATE SOUTHEASTERLY
VERTICAL WIND SHEAR. HOWEVER, THE LLCC IS ALSO MOVING CLOSER TO THE
UPPER RIDGE AXIS, WHICH MAY PROVIDE A REDUCTION IN SHEAR VALUES OVER
THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT
20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR
1007 MB. BECAUSE THE LLCC IS BROAD AND UPPER LEVEL SUPPORT IS JUST
BEGINNING TO IMPROVE, THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS POOR.
(2) NO OTHER SUSPECT AREAS.
3. JUSTIFICATION FOR REISSUE: ADDED POOR AREA IN PARA 2.B.(1).
FORECAST TEAM: CHARLIE//

[Crostorm]

Is 98S ex Billy?

[Crostorm]

(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 15.1S 66.5E
HAS BEEN RELOCATED NEAR 13.4S 69.2E, APPROXIMATELY 420 NM SOUTH-
SOUTHWEST OF DIEGO GARCIA. BASED ON MULTISPECTRAL SATELLITE IMAGERY,
THIS AREA IS A NEW DEVELOPING LOW, SEPARATE FROM THE DISSIPATED
REMAINS OF TC 05S, WHICH TRACKED WESTWARD AND ARE LOCATED NEAR 15S
66E. THEREFORE, THE POSITION WAS MOVED ABOUT 180 NM NORTHEAST OF THE
PREVIOUS POSITION. MULTISPECTRAL SATELLITE IMAGERY AND A 080436Z
AMSU IMAGE INDICATE IMPROVED CONSOLIDATION AND CONVECTIVE BANDING
WRAPPING INTO THE LOW-LEVEL CIRCULATION CENTER (LLCC) WITH GOOD
INFLOW OVER THE NORTHEASTERN QUADRANT. A 080129Z QUIKSCAT IMAGE
SHOWED A SOMEWHAT ELONGATED LLCC WITH MANY 20-25 KNOT UNFLAGGED
WINDS AND ONE 35 KNOT UNFLAGGED WIND NORTH OF THE CENTER,
ASSOCIATED WITH AN INTENSE AREA OF DEEP CONVECTION. A 08/00Z
SHIP REPORT, 95 NM NORTHEAST, ALSO INDICATED 280/33 KNOTS WITH
SLP NEAR 1004 MB. UPPER-LEVEL ANALYSIS INDICATES A GENERALLY
FAVORABLE ENVIRONMENT, ALTHOUGH CURRENTLY LIMITED BY MODERATE TO
HIGH VERTICAL WIND SHEAR (VWS), WITH GOOD RADIAL OUTFLOW AND
WARM SST AND HIGH OCEAN HEAT CONTENT. THE LLCC IS EXPECTED TO
TRACK INTO LOWER VWS AFTER TAU 24 AND SHOULD CONSOLIDATE FURTHER.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1003 MB. BASED
ON THE IMPROVED ORGANIZATION, FORMATIVE BANDING AND GOOD RADIAL
OUTFLOW, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO FAIR.

[Ad Novoxium]

(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 15.1S 66.5E
HAS BEEN RELOCATED NEAR 13.4S 69.2E, APPROXIMATELY 420 NM SOUTH-
SOUTHWEST OF DIEGO GARCIA. BASED ON MULTISPECTRAL SATELLITE IMAGERY,
THIS AREA IS A NEW DEVELOPING LOW, SEPARATE FROM THE DISSIPATED
REMAINS OF TC 05S, WHICH TRACKED WESTWARD AND ARE LOCATED NEAR 15S
66E. THEREFORE, THE POSITION WAS MOVED ABOUT 180 NM NORTHEAST OF THE
PREVIOUS POSITION. MULTISPECTRAL SATELLITE IMAGERY AND A 080436Z
AMSU IMAGE INDICATE IMPROVED CONSOLIDATION AND CONVECTIVE BANDING
WRAPPING INTO THE LOW-LEVEL CIRCULATION CENTER (LLCC) WITH GOOD
INFLOW OVER THE NORTHEASTERN QUADRANT. A 080129Z QUIKSCAT IMAGE
SHOWED A SOMEWHAT ELONGATED LLCC WITH MANY 20-25 KNOT UNFLAGGED
WINDS AND ONE 35 KNOT UNFLAGGED WIND NORTH OF THE CENTER,
ASSOCIATED WITH AN INTENSE AREA OF DEEP CONVECTION. A 08/00Z
SHIP REPORT, 95 NM NORTHEAST, ALSO INDICATED 280/33 KNOTS WITH
SLP NEAR 1004 MB. UPPER-LEVEL ANALYSIS INDICATES A GENERALLY
FAVORABLE ENVIRONMENT, ALTHOUGH CURRENTLY LIMITED BY MODERATE TO
HIGH VERTICAL WIND SHEAR (VWS), WITH GOOD RADIAL OUTFLOW AND
WARM SST AND HIGH OCEAN HEAT CONTENT. THE LLCC IS EXPECTED TO
TRACK INTO LOWER VWS AFTER TAU 24 AND SHOULD CONSOLIDATE FURTHER.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1003 MB. BASED
ON THE IMPROVED ORGANIZATION, FORMATIVE BANDING AND GOOD RADIAL
OUTFLOW, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO FAIR.

So a split in topics is the best way to go here?

[Crostorm]

ZCZC 993
WTIO20 FMEE 080617
SECURITE
WARNING FOR METAREA VIII (S)
ISSUED BY METEO-FRANCE/TROPICAL CYCLONE CENTRE/LA REUNION 08/01/2009
AT
0600 UTC.
WARNING NUMBER: 001/05 (SOUTH-WEST INDIAN OCEAN)
10 MINUTES AVERAGE WIND SPEED IN KNOTS (KT)
(WIND GUSTS AT SEA MAY BE ABOUT 40. STRONGER THAN THE AVERAGED WIND).
MINIMUM SEA LEVEL PRESSURE IN HECTOPASCALS (HPA)
(INDICATIVE FIGURE).
WARNING
BEGINNING OF VALIDITY: THURSDAY 08/01/2009 AT 0600 UTC.
PHENOMENON: ZONE OF DISTURBED WEATHER 5 1004 HPA
POSITION: WITHIN 20 NM RADIUS OF POINT 13.0S / 70.0E
(THIRTEEN DECIMAL ZERO DEGREES SOUTH AND SEVENTY DECIMAL ZERO
DEGREES
EAST) AT 0600 UTC
MOVEMENT: QUASI-STATIONARY
THREAT AREAS:
SQUALLY WEATHER EXISTS WITHIN 250 NM RADIUS FROM THE CENTER,
EXTENDING UP
TO 450 NM IN THE NORTHERN SEMI-CIRCLE.
CLOCKWISE CIRCULATION 15/20 KT AND MODERATE TO ROUGH SEAS NEAR THE
CENTER
, REACHING LOCALLY 25/30 KT IN THE NORTHERN SEMI-CIRCLE.
STRONG GUSTS UNDER SQUALLS.
FORECAST POSITION AND INTENSITY:
12H, VALID 2009/01/08 AT 18 UTC:
15.3S / 68.9E, MAX WIND = 25 KT, TROP. DISTURBANCE.
24H, VALID 2009/01/09 AT 06 UTC:
16.5S / 67.5E, MAX WIND = 30 KT, TROP. DEPRESSION.
OTHER INFORMATIONS:
ASSOCIATED CONVECTION HAS DEVELOPPED LAST NIGHT.
THE SYSTEM IS EXPECTED TO INTENSIFY REGULARY, TRACKING
SOUTHWESTWARDS.=
NNNN

[Crostorm]

[Crostorm]

Update

BULLETIN DU 08 JANVIER A 16H30 LOCALES:

IL N'Y A PAS D'ALERTE EN COURS A LA REUNION, ET AUCUNE
MENACE CYCLONIQUE N'EST ENVISAGEE POUR LES PROCHAINES 72 HEURES.
*****************************************************



NATURE DU SYSTEME DEPRESSIONNAIRE TROPICAL
PRESENT SUR LE SUD-OUEST DE L'OCEAN INDIEN


PERTURBATION TROPICALE 05-20082009

PRESSION ESTIMEE AU CENTRE : 1002 HPA.
POSITION LE 08 JANVIER A 16 HEURES LOCALES: 14.0 SUD / 70.7 EST
(QUATORZE DEGRES ZERO SUD ET SOIXANTE-DIX DEGRES SEPT EST).

DISTANCE DES COTES REUNIONNAISES: 1760 KM A L'EST-NORD-EST
DEPLACEMENT: SUD A 11 KM/H.

VOICI LES INTENSITES ET POSITIONS PREVUES DE CE SYSTEME DEPRESSIONNAIRE AU COURS DES PROCHAINS JOURS

DEPR. TROPICALE, CENTRE POSITIONNE DANS 24H PAR 15S/69.1E
TEMP. TROP. MODEREE, CENTRE POSITIONNE DANS 48H PAR 15.9S/67E
FORTE TEMP. TROP., CENTRE POSITIONNE DANS 72H PAR 17.2S/66.3E


ATTENTION: LES PREVISIONS DE TRAJECTOIRE ET D'INTENSITE
PRECEDENTES SONT A CONSIDERER AVEC LA PLUS GRANDE PRUDENCE
COMPTE TENU DE LEUR INCERTITUDE. ELLES NE CONCERNENT QUE LA
POSITION DU CENTRE DU PHENOMENE, SANS CONSIDERATION SUR SON
EXTENSION.




CE BULLETIN EST A PRESENT TERMINE.
PROCHAIN BULLETIN ENREGISTRE VERS 22H30 LOCALES

[Crostorm]

[HURAKAN]

[Crostorm]

WWIO21 KNES 081450

A. TROPICAL DISTURBANCE (98S)

B. 08/1430Z

C. 13.8S

D. 69.4E

E. FIVE/MET-7

F. T1.0/1.0/D1.0/24HRS

G. IR/EIR/AMSU

H. REMARKS...FT BASED ON PT WITH LITTLE ACTIVE CONVECTION AROUND THE
DEVELOPING CENTER ATTM. WV IMAGERY SHOWS GOOD UPPER OUTFLOW.

I. ADDL POSITIONS

08/0907Z 13.9S 70.8E AMSU

[Chacor]

Now a Tropical Disturbance.

WTIO30 FMEE 081211

RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)

0.A WARNING NUMBER : 2/5/20082009
1.A TROPICAL DISTURBANCE 5

2.A POSITION 2009/01/08 AT 1200 UTC :
WITHIN 20 NM RADIUS OF POINT 14.0S / 70.7E
(FOURTEEN DECIMAL ZERO DEGREES SOUTH AND SEVENTY DECIMAL SEVEN DEGREES
EAST)
MOVEMENT : SOUTH 6 KT

3.A DVORAK ANALYSIS : 2.0/2.0 /D 0.5/6 H
4.A CENTRAL PRESSURE : 1002 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 25 KT
RADIUS OF MAXIMUM WINDS (RMW) : NIL

6.A EXTENSION OF WINDS BY QUADRANTS (KM):


7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 950 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/01/09 00 UTC: 14.0S/70.7E, MAX WIND=025KT, TROP. DISTURBANCE.
24H: 2009/01/09 12 UTC: 15.0S/69.1E, MAX WIND=030KT, TROP. DEPRESSION.
36H: 2009/01/10 00 UTC: 15.6S/67.6E, MAX WIND=035KT, MODERATE TROP. STORM
..
48H: 2009/01/10 12 UTC: 15.9S/67.0E, MAX WIND=040KT, MODERATE TROP. STORM
..
60H: 2009/01/11 00 UTC: 16.4S/66.6E, MAX WIND=045KT, MODERATE TROP. STORM
..
72H: 2009/01/11 12 UTC: 17.2S/66.3E, MAX WIND=055KT, SEVERE TROP. STORM.

2.B OTHER INFORMATIONS:
T=CI=2.0-.
CONVECTION BUILT LAST NIGHT, REMAINS ACTIVE TODAY, FED BY A GOOD MOONSON
FLOW AND A FAVORABLE UPPER LEVELS EQUATORWARDS OUTFLOW.

THE SYSTEM IS EXPECTED TO TRACK SOUTHWESTWARDS DUE TO THE LOW LEVELS
RIDGE IN THE SOUTHEAST, THEN UP TO TAU48, SOUTHWARDS AS THE TROUGH ARRIVE
IN THE SOUTHWEST.
THE SYSTEM SHOULD GO ON INTENSIFY WITH THE SETTING UP TO TAU24 OF A NEW
UPPER LEVELS OUTFLOW DUE TO THE POLAR WESTERLY JET.

Also, it's wrong to refer to this as ex-Billy in the topic now. Billy has dissipated.

[Crostorm]

WTXS21 PGTW 081500
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 13.2S 70.9E TO 19.1S 67.9E
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 IM-
AGERY AT 081400Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 14.0S 70.2E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 05
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.4S
69.2E IS NOW LOCATED NEAR 14.0S 70.2E, APPROXIMATELY 420 NM
SOUTH-SOUTHWEST OF DIEGO GARCIA. ANIMATED INFRARED SATELLITE
IMAGERY AND A 081226Z SSMIS IMAGE CONTINUE TO DEPICT A RAPIDLY
CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC) WITH A DEFINED
LLCC AND MULTIPLE BANDS OF DEEP CONVECTION WRAPPING INTO THE
CENTER. PREVIOUS SHIP REPORTS AND SCATTEROMETER DATA SUPPORT
A 25-30 KNOT SYSTEM WITH SLP NEAR 1002 MB. UPPER-LEVEL ANALYSIS
INDICATES A GENERALLY FAVORABLE ENVIRONMENT, ALTHOUGH CURRENTLY
HINDERED BY MODERATE TO HIGH VERTICAL WIND SHEAR (VWS), WITH
GOOD RADIAL OUTFLOW AND WARM SST AND HIGH OCEAN HEAT CONTENT.
THE LLCC IS EXPECTED TO TRACK INTO LOWER VWS WITHIN 12-24
HOURS AND SHOULD ALSO TAP INTO THE MIDLATITUDE WESTERLY FLOW
TO ITS SOUTH, RESULTING IN IMPROVED POLEWARD OUTFLOW WHICH WILL
ALLOW THE SYSTEM TO STRENGTHEN TO 35 KNOTS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. BASED ON THE
IMPROVED ORGANIZATION, TIGHT BANDING, GOOD RADIAL OUTFLOW AND
EXPECTED TRACK INTO AN IMPROVED ENVIRONMENT, THE POTENTIAL
FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN
THE NEXT 24 HOURS IS GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR
CANCELLED BY 091500Z.//
NNNN

[HURAKAN]

[Chacor]

Should probably split this thread from here onwards into a new 98S thread, and leave the rest as a Billy archive.

[HURAKAN]

Should probably split this thread from here onwards into a new 98S thread, and leave the rest as a Billy archive.

Wish granted!