SWIO: Remnants of TC 21S (Hellen)

[Hurricane_Luis]

Tropical Cyclone Formation Alert Issued




WTXS21 PGTW 262000
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
225 NM EITHER SIDE OF A LINE FROM 10.6S 39.3E TO 13.9S 45.8E
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
IMAGERY AT 262130Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 10.7S 39.8E. THE SYSTEM IS MOVING EASTWARD AT 04 KNOTS.
2. REMARKS:
THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.9S 40.7E IS NOW
LOCATED NEAR 10.7S 39.4E, APPROXIMATELY 600 NM NORTHWEST OF
ANTANANARIVO, MADAGASCAR. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC)
WITH FORMATIVE BANDING WRAPPING INTO THE LLCC. THE LLCC IS OVER LAND
STRADDLING THE TANZANIA-MOZAMBIQUE BORDER AND APPEARS TO BE SLOWLY
APPROACHING THE COAST INTO THE MOZAMBIQUE CHANNEL. UPPER-LEVEL
ANALYSIS INDICATES THE SYSTEM IS IN A FAVORABLE ENVIRONMENT WITH LOW
(5 TO 10 KNOT) VERTICAL WIND SHEAR AND ENHANCED EASTWARD AND
POLEWARD OUTFLOW CHANNELS. ADDITIONALLY, WARM SEA SURFACE
TEMPERATURES IN THE CHANNEL ARE CONDUCIVE FOR FURTHER DEVELOPMENT.
THE DYNAMIC MODELS INDICATE AN EAST-SOUTHEASTWARD TO SOUTHEASTWARD
TRACK WITH RAPID DEVELOPMENT AFTER TAU 24. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1004 MB. IN VIEW OF THE CYCLONES IMMINENT EXIT
INTO WARM WATER AND GIVEN THE FAVORABLE ENVIRONMENTAL 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
272000Z. //
NNNN

[Hurricane_Luis]

Rapidly intensifying then making landfall on the northwestern coast of Madagascar.

[euro6208]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.5S 40.8E
IS NOW LOCATED NEAR 12.8S 40.7E, APPROXIMATELY 515 NM NORTHWEST OF
ANTANANARIVO, MADAGASCAR. ANIMATED SATELLITE IMAGERY SHOWS A
STEADILY CONSOLIDATING SYSTEM WITH FORMATIVE, ALBEIT FRAGMENTED AND
SHALLOW BANDING, WRAPPING INTO A WELL-DEFINED LOW LEVEL CIRCULATION
CENTER (LLCC). THE LLCC HAS MOVED OFFSHORE BUT IS SLOWLY DRIFTING
SOUTHWARD CLOSE TO THE MOZAMBIQUE COAST. UPPER-LEVEL ANALYSIS
INDICATES THE SYSTEM REMAINS IN A FAVORABLE ENVIRONMENT WITH LOW (05
TO 10 KNOT) VERTICAL WIND SHEAR AND STRONG EASTWARD AND POLEWARD
OUTFLOW CHANNELS. ADDITIONALLY, WARM SEA SURFACE TEMPERATURES IN THE
MOZAMBIQUE CHANNEL ARE CONDUCIVE FOR FURTHER DEVELOPMENT. HOWEVER,
THE CYCLONES PROXIMITY TO THE AFRICAN LANDMASS IS LIMITING THE
INFLUX OF MOISTURE NECESSARY FOR FURTHER INTENSIFICATION. IN THE
NEAR TERM, NUMERIC MODELS PREDICT SIGNIFICANT DEVELOPMENT FOLLOWING
A SLOW SOUTHEASTWARD PROGRESSION INTO THE CHANNEL. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. SEE REF A (WTXS21 PGTW
272000) FOR FURTHER DETAILS. IN VIEW OF THE CONTINUED FAVORABLE
ENVIRONMENT AND IN ANTICIPATION OF THE CYCLONE TRACKING INTO OPEN
WATER, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL
CYCLONE WITHIN THE NEXT 24 HOURS REMAINS HIGH.

[stormkite]

21S HELLEN 140329 0600 13.0S 42.8E SHEM 45 989

[TropicalAnalystwx13]

Rapid intensification FTW.

[CrazyC83]

Looks to be shooting up categories like crazy...pinhole eye as well.

[stormkite]

21S HELLEN 140330 0000 14.1S 43.9E SHEM 90 956

Cranking up

[mrbagyo]

TXXS24 KNES 300003
TCSSIO

A. 21S (HELLEN)

B. 29/2330Z

C. 14.1S

D. 43.9E

E. ONE/MET-7

F. T5.0/5.0/D2.0/12HRS

G. IR/EIR/AMSU/TMI

H. REMARKS...SYSTEM HAS DEVELOPED RAPIDLY SINCE LAST CLASSIFICATION.
HOURLY ANALYZES OVER THE PAST 6 HOURS YIELDS AN AVERAGE DT OF 5.0.
CURRENT DT IS 5.5 BASED ON MEDIUM GRAY EYE WITH A COLD MEDIUM GRAY
RING EMBEDDED IN BLACK. MET IS 4.5 BASED ON RAPID DEVELOPMENT OVER THE
PAST 24HRS. PT IS 5.0. FT IS BASED ON AVERAGE DT OVER THE PAST 6 HOURS
THAT DID NOT JUSTIFY BREAKING SEVERAL CONSTRAINTS.

I. ADDL POSITIONS

29/1816Z 13.7S 43.7E AMSU
29/1840Z 13.7S 43.8E TMI


...LIDDICK

[stormkite]

S Indian Ocean: Storm Alert issued at 30 Mar, 2014 0:00 GMT

Tropical Cyclone HELLEN (21S) currently located near 14.1 S 43.9 E is forecast to strike land to the following likelihood(s) at the given lead time(s):

Red Alert Country(s) or Province(s)
Madagascar
probability for CAT 1 or above is 50% in about 48 hours
probability for TS is 90% in about 24 hours
Red Alert City(s) and Town(s)
Soalala (16.1 S, 45.3 E)
probability for CAT 1 or above is 40% in about 36 hours
probability for TS is 85% in about 24 hours

Yellow Alert Country(s) or Province(s)
Mayotte
probability for TS is 80% currently
Comoros
probability for TS is 65% currently
Yellow Alert City(s) and Town(s)
Mahajanga (15.7 S, 46.4 E)
probability for CAT 1 or above is 20% in about 36 hours
probability for TS is 75% in about 36 hours
Besalampy (16.7 S, 44.5 E)
probability for TS is 70% in about 24 hours
Dzaoudzi (12.8 S, 45.3 E)
probability for TS is 60% currently

Note that
Red Alert (Severe) is CAT 1 or above to between 31% and 100% probability.
Yellow Alert (Elevated) is CAT 1 or above to between 10% and 30% probability, or TS to above 50% probability.
CAT 1 means Tropical Cyclone strength winds of at least 74 mph, 119 km/h or 64 knots 1-min sustained.
TS means Tropical Storm strength winds of at least 39 mph, 63 km/h or 34 knots 1-min sustained.

For graphical forecast information and further details please visit http://www.tropicalstormrisk.com/


21S HELLEN 140330 0600 14.5S 44.3E SHEM 105 944

[stormkite]

If Helen stays off land looks like it will bomb right out structure now appears to be excellent on sat-pic.



Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

[stormkite]

21S HELLEN 140330 0600 14.4S 44.3E SHEM 115 937

[mrbagyo]

gorgeous looking system... DT now at 6.







TXXS24 KNES 300601
TCSSIO

A. 21S (HELLEN)

B. 30/0530Z

C. 14.4S

D. 44.3E

E. ONE/MET-7

F. T6.0/6.0/D3.0/24HRS

G. IR/EIR/VIS/AMSU

H. REMARKS...OW EYE IS EMBEDDED IN W AND SURROUNDED BY CMG WHICH RESULTS
IN A DT OF 6.5 AFTER 0.5 IS ADDED AS AN EYE ADJUSTMENT. THE AVERAGE DT
CALCULATED HOURLY OVER THE LAST 6 HOURS ENDING AT 0530Z WAS 6.2. THIS
IS THE BASIS FOR THE FT AND JUSTIFIES BREAKING DVORAK CONSTRAINTS. PT
AND MET ARE UNREPRESENTATIVE AT 5.0 AND 4.5, RESPECTIVELY.

I. ADDL POSITIONS

30/0107Z 14.3S 44.0E AMSU


...TURK

[mrbagyo]

ZCZC 249
WTIO30 FMEE 300053
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 9/14/20132014
1.A TROPICAL CYCLONE 14 (HELLEN)
2.A POSITION 2014/03/30 AT 0000 UTC:
WITHIN 21 NM RADIUS OF POINT 14.1 S / 44.0 E
(FOURTEEN DECIMAL ONE DEGREES SOUTH AND FORTY FOUR DECIMAL
ZERO DEGREES EAST)
MOVEMENT : SOUTH-SOUTH-EAST 7 KT
3.A DVORAK ANALYSIS: 5.0/5.0/D 1.0/6 H
4.A CENTRAL PRESSURE: 970 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 80 KT
RADIUS OF MAXIMUM WINDS (RMW) :19 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 130 SE: 140 SW: 130 NW: 90
34 KT NE: 100 SE: 100 SW: 70 NW: 70
48 KT NE: 60 SE: 60 SW: 60 NW: 60
64 KT NE: 40 SE: 40 SW: 40 NW: 40
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1006 HPA / 700 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP
1.B FORECASTS:
12H: 2014/03/30 12 UTC: 14.5 S / 44.9 E, MAX WIND=075 KT, TROPICAL
CYCLONE
24H: 2014/03/31 00 UTC: 14.5 S / 45.0 E, MAX WIND=065 KT, TROPICAL
CYCLONE
36H: 2014/03/31 12 UTC: 14.8 S / 44.5 E, MAX WIND=050 KT, SEVERE
TROPICAL STORM
48H: 2014/04/01 00 UTC: 14.9 S / 43.8 E, MAX WIND=040 KT, MODERATE
TROPICAL STORM
60H: 2014/04/01 12 UTC: 15.1 S / 42.9 E, MAX WIND=035 KT, MODERATE
TROPICAL STORM
72H: 2014/04/02 00 UTC: 15.5 S / 42.2 E, MAX WIND=035 KT, MODERATE
TROPICAL STORM
2.B LONGER-RANGE OUTLOOK :
96H: 2014/04/03 00 UTC: 16.2 S / 40.1 E, MAX WIND=035 KT, MODERATE
TROPICAL STORM
120H: 2014/04/04 00 UTC: 16.5 S / 37.7 E, MAX WIND=000 , INLAND
2.C ADDITIONAL INFORMATIONS:
T=CI=5.0
HELLEN KEEPS ON INTENSIFYING RAPIDLY AND SHOWS A PINHOLE EYE IN IR
IMAGERY SINCE 21Z.
UNDER THE STEERING INFLUENCE OF THE MID-LEVELS RIDGE LOCATED
NORTHWARD, HELLEN WILL KEEP ON TRACKING SOUTH-EASTWARDS DURING THE
NEXT 24 HOURS.
ALONG-TRACK ENVIRONMENTAL CONDITIONS ARE FAVOURABLE DURING THE NEXT
12 TO 24 HOURS.
SYSTEM IS LYING UNDER AN UPPER LEVEL RIDGE AXIS ALOFT. VERTICAL
WINDSHEAR IS WEAK (5M/S ACCORDING TO CIMSS AT 1800Z) AND UPPER LEVEL
DIVERGENCE IS GOOD MAINLY POLEWARD IN RELATIONSHIP WITH A WESTERLY
SUBTROPICAL JET EXISTING SOUTH OF 18S.
SST ARE VERY HIGH OVER THIS AREA (29/30 DEGREES CELCIUS).
SUNDAY LATE, THE MID-TROPOSPHERIC NEAR-EQUATORIAL RIDGE IS EXPECTED
TO WEAKEN. HELLEN IS THEREFORE EXPECTED TO SLOW DOWN CLEARLY.
ON AND AFTER MONDAY, HELLEN SHOULD RE-CURVE WESTWARDS THEN
SOUTH-WESTWARDS UNDER THE STEERING INFLUENCE OF THE SUBTROPICAL RIDGE
REBUILDING SOUTHWARD.
HELLEN SHOULD KEEP ON TRACKING ON THIS WEST-SOUTH-WEST PATH UP TO ITS
LANDFALL WEDNESDAY NIGHT OR THURSDAY ON THE MOZAMBICAN COASTLINES IN
THE AREA OF QUELIMANE.
ON THIS EXPECTED PATH, THE UPPER LEVEL WINDSHEAR STRENGTHENING MONDAY
IS EXPECTED TO WEAKEN CLEARLY THIS SMALL SYSTEM .
ON TUESDAY AND WEDNESDAY, THE UPPER LEVEL WINDSHEAR IS EXPECTED TO
WEAKEN AGAIN.
THE INTENSITY FORECAST IS UNCERTAIN ACCORDING TO THE SMALL SIZE OF
THE SYSTEM AND ITS SENSIBILITY TO THE VARIATION OF THE ENVIRONMENTAL
CONDITIONS.
IT IS NOT TOTALLY EXCLUDED THAT SYSTEM GET MORE CLOSER TO MADAGASCAR
THAN THE MENTIONNED FORECAST.
SOME AVAILABLE NWP MODELS SUGGEST A TRACK CLOSE TO MAHAJONGA OR
BESALAMPY COASTLINES.
GIVEN THE VICINITY OF THE COMOROS ARCHIPELAGO AND MAYOTTE, THE
INHABITANTS OF THIS ISLANDS SHOULD CLOSELY MONITOR THE PROGRESS OF
THIS SYSTEM. THE INHABITANTS OF THE NORTH-WESTERN COASTS OF
MADAGASCAR SHOULD ALSO MONITOR THE PROGRESS OF THIS SYSTEM.=
NNNN

[xtyphooncyclonex]

I have never followed the SIO before, therefore I'm used to Pacific typhoons. I think this one is among the best looking category 4 cyclones I have ever seen. Let's see if this could intensify into a category 5 and get record intensity in this basin in this period of time [late-season].

I hope Madagascar, especially Mahajanga and the rest of western Madagascar anticipated for this storm and doing the proper preparations for this monster cyclone.

[jaguarjace]

[xtyphooncyclonex]

One word. IMPRESSIVE.

[stormkite]

One word. IMPRESSIVE.

21S HELLEN 140330 1200 14.7S 44.6E SHEM 130 926

[xtyphooncyclonex]

JTWC forecasts a category 5 cyclone onshore Mahajanga, Madagascar and it could be the strongest this season.

[mrbagyo]

TXXS24 KNES 301155
TCSSIO

A. 21S (HELLEN)

B. 30/1130Z

C. 14.7S

D. 44.6E

E. ONE/MET-7

F. T6.5/6.5/D3.5/24HRS

G. IR/EIR/VIS

H. REMARKS...WMG EYE IS EMBEDDED IN W AND SURROUNDED BY CMG RESULTING IN
A DT OF 7.0 AFTER 1.0 ADDED FOR EYE ADJUSTMENT. DT AVERAGE CALCULATED
OVER LAST 6 HOURS IS 6.6. MET = 4.5 AND PT = 5.0. FT OF 6.5 IS BASED
ON RAPID INTENSIFICATION AND CALCULATED 6 HOUR AVERAGE.

I. ADDL POSITIONS

NIL


...KIBLER

RSMC La Reunion :
ZCZC 357
WTIO30 FMEE 301311
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 11/14/20132014
1.A INTENSE TROPICAL CYCLONE 14 (HELLEN)
2.A POSITION 2014/03/30 AT 1200 UTC:
WITHIN 10 NM RADIUS OF POINT 14.7 S / 44.7 E
(FOURTEEN DECIMAL SEVEN DEGREES SOUTH AND FORTY FOUR DECIMAL SEVEN DEGREES EAST)
MOVEMENT : SOUTH-EAST 4 KT
3.A DVORAK ANALYSIS: 6.5/6.5/D 3.0/24 H
4.A CENTRAL PRESSURE: 935 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 115 KT
RADIUS OF MAXIMUM WINDS (RMW) :17 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 110 SE: 180 SW: 180 NW: 130
34 KT NE: 70 SE: 90 SW: 100 NW: 90
48 KT NE: 60 SE: 60 SW: 60 NW: 60
64 KT NE: 50 SE: 50 SW: 50 NW: 50
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1008 HPA / 500 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP
1.B FORECASTS:
12H: 2014/03/31 00 UTC: 15.2 S / 45.0 E, MAX WIND=110 KT, INTENSE TROPICAL CYCLONE
24H: 2014/03/31 12 UTC: 15.7 S / 45.0 E, MAX WIND=090 KT, INTENSE TROPICAL CYCLONE
36H: 2014/04/01 00 UTC: 16.0 S / 44.6 E, MAX WIND=090 KT, INTENSE TROPICAL CYCLONE
48H: 2014/04/01 12 UTC: 16.6 S / 43.8 E, MAX WIND=070 KT, TROPICAL CYCLONE
60H: 2014/04/02 00 UTC: 17.1 S / 42.9 E, MAX WIND=070 KT, TROPICAL CYCLONE
72H: 2014/04/02 12 UTC: 17.4 S / 41.9 E, MAX WIND=075 KT, TROPICAL CYCLONE
2.B LONGER-RANGE OUTLOOK :
96H: 2014/04/03 12 UTC: 17.9 S / 39.8 E, MAX WIND=080 KT, TROPICAL CYCLONE
120H: 2014/04/04 12 UTC: 17.7 S / 37.3 E, MAX WIND=080 KT, TROPICAL CYCLONE
2.C ADDITIONAL INFORMATIONS:
T=CI=6.5+
HELLEN HAS CONTINUED TO INTENSIFY DURING THE LAST 6 HOURS WITH AN IMPRESSIVE WELL DEFINED 18NM WID
E EYE. THE CURRENT ESTIMATION OF THE INTENSITY IS BASED ON MANUAL DVORAK ESTIMATES WITH A 3 HR AVE
RAGE AT 6.7 IN GOOD AGREEMENT WITH THE NESDIS ADT AT 6.9 AT 1200Z. RAW DT IS AT 7.0 SINCE 11Z AND
NESDIS ADT IS AT 6.9 AT 12Z. ON THIS BASIS THE SYSTEM SHOULD REACH THE VERY INTENSE TROPICAL CYCLO
NE STAGE WITHIN THE NEXT FEW HOURS. HELLEN IS LIKELY TO BE ONE OF THE MOST POWERFULL TROPICAL CYCL
ONE EVER SEEN OVER THE NORTHERN CHANNEL SINCE THE SATELLITE ERA.
THE SYSTEM IS LYING UNDER AN UPPER LEVEL RIDGE AXIS ALOFT. VERTICAL WINDSHEAR IS WEAK (4.4 M/S ACC
ORDING TO CIMSS AT 1200Z) AND UPPER LEVEL DIVERGENCE IS GOOD MAINLY POLEWARD IN RELATIONSHIP WITH
A WESTERLY SUBTROPICAL JET EXISTING SOUTH OF 18S.UNDER THE STEERING INFLUENCE OF THE MID-LEVELS RI
DGE LOCATED NORTHWARD, HELLEN WILL KEEP ON TRACKING SLOWLY SOUTH-EASTWARDS DURING THE NEXT 6 HOURS
BEFORE BEING WITHIN A TOO SLOW STEERING ENVIRONMENT THAT SHOULD LEAD TO A QUASI-STAT MOTION. A WE
AKENING TREND INITIATED BY INDUCED COLD SST MAY TAKEN PLACE BY THAT TIME. ON THE HAND SOME NWP MOD
ELS SUGGEST A TEMPORARILY RISING OF THE VWS TONIGHT. THE INTENSITY FORECAST REMAINS UNCERTAIN ACCO
RDING TO THE SMALL SIZE OF THE SYSTEM AND ITS SENSIBILITY TO THE VARIATION OF THE ENVIRONMENTAL CO
NDITIONS.
SUNDAY NIGHT, THE MID-TROPOSPHERIC NEAR-EQUATORIAL RIDGE IS EXPECTED TO WEAKEN. HELLEN IS THEREFOR
E EXPECTED TO SLOW DOWN CLEARLY.
ON AND AFTER MONDAY, HELLEN SHOULD RE-CURVE WESTWARDS THEN SOUTH-WESTWARDS UNDER THE STEERING INFL
UENCE OF THE SUBTROPICAL RIDGE REBUILDING SOUTHWARD.
HELLEN SHOULD KEEP ON TRACKING ON THIS WEST-SOUTH-WEST PATH UP TO ITS LANDFALL WEDNESDAY NIGHT OR
THURSDAY ON THE MOZAMBICAN COASTLINES IN THE AREA OF QUELIMANE. GIVEN THE FAVOURABLE WINDS PATTERN
SEEN ON NWP MODELS AT THIS LEAD TIME, THE INTENSITY FORECAST IS SIGNIFICANTLY UPGRADED.
THE TRACK FORECASTHAS BEEN ADJUSTED SOUTHWARDS AND LIES BETWEEN THE ECMWF AND GFS TRACKS. THE INHA
BITANTS OF THE NORTH-WESTERN COASTS OF MADAGASCAR EMBRACED FOR AN EXTREMELY DANGEROUS TROPICAL CYC
LONE. ALL PREPARATIONS FOR A "WORST CASE" SCENARIO SHOULD BE UNDERWAY AS A LANDFALLING INTENSE SYS
TEM IS STILL CLEARLY A POSSIBILITY.
GIVEN THE VICINITY OF THE COMOROS ARCHIPELAGO AND MAYOTTE, THE INHABITANTS OF THIS ISLANDS SHOULD
STILL CLOSELY MONITOR THE PROGRESS OF THIS SYSTEM.
NNNN

[mrbagyo]