SIO: TROPICAL DISTURBANCE (08/27U/99S)

[HURAKAN]

At midday WST a third low was near 11S 093E and was slow moving. This low is
expected to remain slow moving and may develop over the next few days.

Likelihood of this system being a tropical cyclone in the Western Region:
Tuesday :Low
Wednesday :Moderate
Thursday :Moderate

[HURAKAN]

AN AREA OF CONVECTION NEAR 11.8S 89.7E HAS SHOWN
PERSISTENT CONVECTION AND INCREASING ORGANIZATION DURING THE PAST
12 HOURS. A 281137Z 91HZ SSMIS IMAGE REVEALS ORGANIZED DEEP
CONVECTION OVER THE WESTERN QUADRANT. THE INITIAL PGTW DVORAK
INTENSITY ESTIMATE IS 25 KNOTS. THE 281200Z STREAMLINE ANALYSIS
INDICATES THE AREA EXISTS IN A REGION OF HIGH DIFFLUENCE AND WEAK
VERTICAL WINDSHEAR. SEA SURFACE TEMPERATURES IN THE AREA ARE
FAVORABLE FOR DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1006 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS POOR.

[HURAKAN]

GFS expects this system to intensify

[HURAKAN]

Latest visible

[HURAKAN]

Wrong advisory ... mods, delete this post!

[HURAKAN]

exposed

[HURAKAN]

Latest

[HURAKAN]

ZCZC 829
WTIO30 FMEE 291243
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 3/8/20102011
1.A TROPICAL DISTURBANCE 8
2.A POSITION 2011/03/29 AT 1200 UTC :
WITHIN 20 NM RADIUS OF POINT 9.8S / 88.5E
(NINE DECIMAL EIGHT DEGREES SOUTH AND EIGHTY EIGHT DECIMAL FIVE DEGREES
EAST)
MOVEMENT : QUASI-STATIONARY
3.A DVORAK ANALYSIS : 1.5/2.0 /W 0.5/6 H
4.A CENTRAL PRESSURE : 1005 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):
NIL
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 260 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM
1.B FORECASTS:
12H: 2011/03/30 00 UTC: 09.5S/88.3E, MAX WIND=025KT, TROP. DISTURBANCE.
24H: 2011/03/30 12 UTC: 09.0S/88.3E, MAX WIND=025KT, TROP. DISTURBANCE.
36H: 2011/03/31 00 UTC: 08.8S/88.6E, MAX WIND=025KT, TROP. DISTURBANCE.
48H: 2011/03/31 12 UTC: 08.7S/89.3E, MAX WIND=025KT, TROP. DISTURBANCE.
60H: 2011/04/01 00 UTC: 08.9S/89.8E, MAX WIND=025KT, TROP. DISTURBANCE.
72H: 2011/04/01 12 UTC: 09.4S/90.1E, MAX WIND=030KT, TROP. DEPRESSION.
2.B LONGER-RANGE OUTLOOK:
96H: 02/04/2011 12 UTC: 10.1S/89.5E, MAX WIND=035KT, MODERATE TROP.
STORM.
120H: 03/04/2011 12 UTC: 10.4S/87.9E, MAX WIND=035KT, MODERATE TROP.
STORM.
2.C ADDITIONAL INFORMATIONS:
T=1.5 CI=2.0
ALL ALONG THE DAY, DEEP CONVECTION HAS BEEN REMOVED UP TO MORE THAN 1
DEGREE TO THE SOUTHWEST OF THE LLCC. SINCE 1030Z, A SMALL CLUSTER HAS
RESTARTED CLOSE TO THE CENTER.
THE SYSTEM IS EMBEDDED WITHIN A CONTRADICTORY STEERING FLOW ENVIRONMENT
BETWEEN THE LOW LEVEL EQUATORIAL WESTERLY FLOW TO THE NORTH AND THE
EASTERN FLOW TO THE SOUTH ASSOCIATED TO THE SUBTROPICAL RIDGE. WITHIN THE
NEXT FEW DAYS, STEERING FLOW FROM THE SUBTROPICAL RIDGE SHOULD GRADUALLY
EASE OFF. ALL
NWP GUIDANCE SHOW NOW A SLOW DRIFT OF THE TRACK DURING MOST OF THE
FORECAST PERIOD, WITH A NORTHWARDS DRIFT WEDNESDAY FOLLOWED BY AN
EASTWARDS AND THEN SOUTHWARDS DRIFT THURSDAY AND FRIDAY. AT LONGER RANGE,
A STRONG RIDGE IS FORECAST TO BUILT SOUTH OF THE SYSTEM AND TRACK COULD
RESUME WESTWARDS OR
WESTSOUTHWESTWARDS.
THE SYSTEM IS NOW CLOSE TO AN AREA OF STRONG EASTERLY SHEAR (CF CIMSS
ANALYSIS). CONSEQUENTLY, THE POTENTIAL FOR FURTHER INTENSIFICATION SEEMS
TO BE POOR WITHIN THE NEXT 3 DAYS. BEYOND, A SLOW INTENSIFICATION IS
POSSIBLE ASSOCIATED WITH A BETTER LOW LEVEL INFLOW SEEN IN NWP FIELDS.
HOWEVER SHEAR IS
EXPECTED TO REMAIN AND SHOULD LIMIT INTENSIFICATION.
THIS FORECAST REMAINS UNCERTAIN ... A LIKELY POSSIBILITY IS THAT THE
SYSTEM GRADUALLY DISSIPATE WITHIN THE NEXT THREE DAYS AND TRACKS
EASTWARDS WITHIN THE EQUATORIAL WESTERLY FLOW ...
CURRENT INTENSITY DOES NOT JUSTIFY ISSUANCE OF REGULAR ADVISORY.
NNNN

[HURAKAN]

latest visible ... exposed

[HURAKAN]

ZCZC 685
WTIO30 FMEE 300041
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 4/8/20102011
1.A TROPICAL DISTURBANCE 8
2.A POSITION 2011/03/30 AT 0000 UTC :
WITHIN 40 NM RADIUS OF POINT 9.3S / 88.1E
(NINE DECIMAL THREE DEGREES SOUTH AND EIGHTY EIGHT DECIMAL ONE DEGREES
EAST)
MOVEMENT : NORTH-WEST 3 KT
3.A DVORAK ANALYSIS : 2.0/2.0 /D 0.5/24 H
4.A CENTRAL PRESSURE : 1004 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):
28 KT NE: SE: SO: 180 NO: 150
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 370 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM
1.B FORECASTS:
12H: 2011/03/30 12 UTC: 08.6S/88.1E, MAX WIND=025KT, TROP. DISTURBANCE.
24H: 2011/03/31 00 UTC: 08.3S/88.7E, MAX WIND=030KT, TROP. DEPRESSION.
36H: 2011/03/31 12 UTC: 08.5S/89.3E, MAX WIND=030KT, TROP. DEPRESSION.
48H: 2011/04/01 00 UTC: 08.9S/89.7E, MAX WIND=030KT, TROP. DEPRESSION.
60H: 2011/04/01 12 UTC: 09.7S/89.9E, MAX WIND=030KT, TROP. DEPRESSION.
72H: 2011/04/02 00 UTC: 10.6S/89.8E, MAX WIND=035KT, MODERATE TROP. STORM
.
2.B LONGER-RANGE OUTLOOK:
96H: 03/04/2011 00 UTC: 11.7S/88.5E, MAX WIND=035KT, MODERATE TROP.
STORM.
120H: 04/04/2011 00 UTC: 12.2S/86.7E, MAX WIND=030KT, TROP. DEPRESSION.
2.C ADDITIONAL INFORMATIONS:
T=2.0 CI=2.0
DEEP CONVECTION REMAINED CLOSE TO THE CENTER UNTIL 23UTC, BUT LAST IR
IMAGERY DEPICTS A WEAKENING OF CONVECTIVE ACTIVITY.
PRESENT POSIION IS AN EXTRAPOLATION OF MW AQUA FIX AT 19.24UTC.
SYSTEM NR8 CONTINUES TO STRUGGLE IN A RATHER HOSTILE ENVIRONMENT :
UNDIRECT MONSOON INFLOW AND MODERATE UPPER LEVEL EASTERLY VERTICAL WIND
SHEAR.
IT MOVES SLOWLY NORTH-WESTWARD.
LAST AVALAIBLE NWP MODELS ARE NOW IN A BETTER GOOD AGREEMENT FOR A
CLOCKWISE LOOP FOR THE NEXT 3 DAYS. BEYOND THE STEERING CURRENT SHOULD BE
AGAIN THE SUBTROPICAL RIDGE EAST-NORTH-EASTERN FLOW.
FOR THE NEXT 2 DAYS SYSTEM SHOULD REMAIN CLOSE TO THE STRONG UPPER LEVEL
VERTICAL WIND SHEAR NORTH OF 10S (CF CIMSS ANALYSIS).
ON SATURDAY (J+3) UPPER LEVELS CONDITIONS SHOULD BECOME TEMPORARILY MORE
FAVORABLE WITH A BETTER UPPER LEVEL DIVERGENCE. BEYOND (J+4/J+5) UPPER
LEVEL WIND SHEAR IS EXPECTED TO STRENGTHEN AGAIN.
CURRENT INTENSITY DOES NOT JUSTIFY ISSUANCE OF REGULAR ADVISORY.
NNNN

[Extratropical94]

At midday WST a third low [27U] was near 09S 088E and was slow moving. This low
may develop over the next few days, and may re-enter the Western Region.

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

Chance of reentering into Aussie region

[HURAKAN]

remains exposed

[Extratropical94]

WTIO30 FMEE 301220


RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)

0.A WARNING NUMBER : 5/8/20102011
1.A TROPICAL DISTURBANCE 8

2.A POSITION 2011/03/30 AT 1200 UTC :
WITHIN 20 NM RADIUS OF POINT 8.2S / 87.8E
(EIGHT DECIMAL TWO DEGREES SOUTH AND EIGHTY SEVEN DECIMAL EIGHT DEGREES
EAST)
MOVEMENT : NORTH-NORTH-EAST 5 KT

3.A DVORAK ANALYSIS : 1.5/2.0 /W 0.5/12 H
4.A CENTRAL PRESSURE : 1004 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 25 KT
RADIUS OF MAXIMUM WINDS (RMW) : 33 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
28 KT NE: SE: SO: 055 NO: 150

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 450 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM

1.B FORECASTS:
12H: 2011/03/31 00 UTC: 07.9S/88.1E, MAX WIND=025KT, TROP. DISTURBANCE.
24H: 2011/03/31 12 UTC: 07.6S/88.6E, MAX WIND=025KT, TROP. DISTURBANCE.
36H: 2011/04/01 00 UTC: 08.1S/89.0E, MAX WIND=025KT, TROP. DISTURBANCE.
48H: 2011/04/01 12 UTC: 08.7S/89.1E, MAX WIND=025KT, TROP. DISTURBANCE.
60H: 2011/04/02 00 UTC: 09.2S/88.8E, MAX WIND=025KT, TROP. DISTURBANCE.
72H: 2011/04/02 12 UTC: 09.7S/88.3E, MAX WIND=030KT, TROP. DEPRESSION.

2.B LONGER-RANGE OUTLOOK:
96H: 03/04/2011 12 UTC: 10.3S/86.4E, MAX WIND=040KT, MODERATE TROP.
STORM.
120H: 04/04/2011 12 UTC: 11.2S/83.4E, MAX WIND=050KT, SEVERE TROP. STORM.

2.C ADDITIONAL INFORMATIONS:
T=2.0 AND CI=2.0
SYSTEM KEEPS ON UNDERGOING A MODERATE UPPER LEVEL EASTERLY VERTICAL WIND
SHEAR AND LOW LEVEL VORTEX IS TOTALLY EXPOSED IN THE NORTHEAST OF THE
MAIN DEEP CONVECTIVE ACTIVITY.
SYSTEM KEEPS ON DRIFTING NORTHEASTWARDS SINCE 30/0600Z.
LAST AVAILABLE NWP (ECMWF, UKMO, GFS) ARE IN A RATHER GOOD AGREEMENT ON
FORECASTING A MORE OR LESS BROAD CLOCKWISE LOOP FOR THE NEXT 3 DAYS.
BEYOND THE STEERING CURRENT SHOULD BE BACK THE SUBTROPICAL RIDGE
EAST-NORTH-EASTERN FLOW.
SYSTEM IS NOT EXPECTED TO DEEPEN SIGNIFICANTLY WITHIN THIS LOOP.
ECMWF NWP MODEL FORECASTS A GRADUALLY DEEPENING ON AND AFETR SUNDAY 3
APRIL AS SYSTEM EVOLVES IN IMPROVING UPPER LEVEL ENVIRONMENTAL CONDITIONS
.

CURRENT INTENSITY DOES NOT JUSTIFY ISSUANCE OF REGULAR ADVISORY.

Short-term intensity forecast has been downgraded, but the outlook now predicts a STS
Hopefully it will intensify and become a nice fish-storm...

[HURAKAN]

the shear is relentless

[HURAKAN]

exposed