SIO: GAEL - Severe Tropical Storm - Discussion

[Crostorm]

[Crostorm]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 08 FEB 2009 Time : 223000 UTC
Lat : 26:30:00 S Lon : 54:53:32 E


CI# /Pressure/ Vmax
5.9 / 929.1mb/112.4kt


Final T# Adj T# Raw T#
(3hr avg)
5.2 5.9 6.1

Latitude bias adjustment to MSLP : -0.7mb

Estimated radius of max. wind based on IR :N/A km

Center Temp : -17.5C Cloud Region Temp : -70.1C

Scene Type : EYE

Positioning Method : SPIRAL ANALYSIS

Ocean Basin : INDIAN
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : 0.5T/hour
Weakening Flag : ON
Rapid Dissipation Flag : FLAG

****************************************************

[Crostorm]

[Crostorm]

02/07/2009 7:15 UTC

[Crostorm]

172
WTIO30 FMEE 090012

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

0.A WARNING NUMBER : 29/8/20082009
1.A TROPICAL CYCLONE 8 (GAEL)

2.A POSITION 2009/02/09 AT 0000 UTC :
WITHIN 30 NM RADIUS OF POINT 26.6S / 54.8E
(TWENTY SIX DECIMAL SIX DEGREES SOUTH AND FIFTY FOUR DECIMAL EIGHT
DEGREES EAST)
MOVEMENT : SOUTH-SOUTH-EAST 14 KT

3.A DVORAK ANALYSIS : 5.5/5.5 /D 1.0/12 H
4.A CENTRAL PRESSURE : 940 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 85 KT
RADIUS OF MAXIMUM WINDS (RMW) : 35 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 550 SE: 400 SO: 450 NO: 300
50 KT NE: 170 SE: 200 SO: 150 NO: 050

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA / 1100 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/02/09 12 UTC: 28.9S/56.4E, MAX WIND=070KT, TROPICAL CYCLONE.
24H: 2009/02/10 00 UTC: 30.9S/58.7E, MAX WIND=060KT, BECOMING
EXTRATROPICAL.
36H: 2009/02/10 12 UTC: 31.9S/60.4E, MAX WIND=055KT, EXTRATROPICAL.
48H: 2009/02/11 00 UTC: 32.5S/61.7E, MAX WIND=050KT, EXTRATROPICAL.
60H: 2009/02/11 12 UTC: 33.2S/63.4E, MAX WIND=045KT, EXTRATROPICAL.
72H: 2009/02/12 00 UTC: 34.7S/66.8E, MAX WIND=035KT, EXTRATROPICAL.

2.B OTHER INFORMATIONS:
T=5.5 AND CI=5.5
GAEL HAS TEMPORARELY STOPPED WEAKENING AND HAS SO FACT SLIGHTLY
RE-INTENSIFY WITHIN THE RECENT PAST HOURS PROBABLY DUE TO A LESS UPPER
LEVEL CONSTRAINT (TILD BETWEEN
37GHZ AND 85GHZ IS NO MORE SO BIG ON TRMM 1548Z - AQUA 2140Z)
SYSTEM IS HOWEVER EXPECTED TO UNDERGO LESS FAVORABLE CONDITIONS AT UPPER
LEVELS AND EXPECTED TO WEAKEN ON COOLER SEA.

CYCLONIC SWELL OF 3M TO 5M ON AVERAGE ASSOCIATED WITH DANGEROUS BATTERING
WAVES CONTINUE TO HIT EXPOSED COASTS OF MADAGASCAR AND MAURITIUS/ LA
REUNION.

NO MAJOR CHANGES CAME FROM THE 12Z RUN. AVAILABLE DYNAMICAL GUIDANCE IS
IN VERY GOOD AGREEMENT. UNDER THE STEERING INFLUENCE OF A MID TO UPPER
LEVEL RIDGE LOCATED EAST OF THE SYSTEM AND BETWEEN 60E AND 65E, GAEL IS
GOING TO KEEP ON SPEEDING UP SOUTH-SOUTHEASTWARDS WITHIN THE NEXT 24 TO
36 HOURS IN A
LESS AND LESS FAVOURABLE ENVIRONMENT (NORTHWESTERLY WINDSHEAR STRONGER
STARTING THIS COMING NIGHT AND THEN INSUFFICIENT OCEAN HEAT POTENTIAL AS
THE SSTS BECOME COOL) AND TO WEAK BEFORE BEGINNING ITS EXTRATROPICAL
TRANSITION.
AT THE END OF THE FORECAST RANGE, A BUILDING MID-LEVEL RIDGE FROM THE
SOUTHWEST COULD SLOW DOWN THE EXTRATROPICAL EXIT OF GAEL.


.

[Squarethecircle]

02/07/2009 7:15 UTC

That's a really fantastic image. Reminds me a bit of Gafilo, though not as big and with a less beautiful eye.

[HURAKAN]

[HURAKAN]

[HURAKAN]

ET is calling.

[HURAKAN]

Going down fast.

[HURAKAN]

317
WTIO30 FMEE 090614

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

0.A WARNING NUMBER : 30/8/20082009
1.A TROPICAL CYCLONE 8 (GAEL)

2.A POSITION 2009/02/09 AT 0600 UTC :
WITHIN 20 NM RADIUS OF POINT 28.2S / 56.4E
(TWENTY EIGHT DECIMAL TWO DEGREES SOUTH AND FIFTY SIX DECIMAL FOUR
DEGREES EAST)
MOVEMENT : SOUTH-EAST 16 KT

3.A DVORAK ANALYSIS : 5.0/5.0 /W 0.5/24 H
4.A CENTRAL PRESSURE : 950 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 80 KT
RADIUS OF MAXIMUM WINDS (RMW) : 35 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 700 SE: 700 SO: 700 NO: 500
50 KT NE: 160 SE: 150 SO: 070 NO: 070

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1006 HPA
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/02/09 18 UTC: 30.1S/58.2E, MAX WIND=070KT, BECOMING
EXTRATROPICAL.
24H: 2009/02/10 06 UTC: 31.4S/59.9E, MAX WIND=060KT, EXTRATROPICAL.
36H: 2009/02/10 18 UTC: 32.2S/61.4E, MAX WIND=050KT, EXTRATROPICAL.
48H: 2009/02/11 06 UTC: 32.7S/63.4E, MAX WIND=045KT, EXTRATROPICAL.
60H: 2009/02/11 18 UTC: 33.5S/65.5E, MAX WIND=040KT, EXTRATROPICAL.
72H: 2009/02/12 06 UTC: 34.8S/68.4E, MAX WIND=035KT, EXTRATROPICAL.

2.B OTHER INFORMATIONS:
T=5.0 AND CI=5.0+.
GAEL HAS ACCELERATED SOUTHEASTWARDS, AND UNDERGOES AGAIN NORTHWESTERLY
VERTICAL WIND SHEAR.(TILD BETWEEN 37GHZ AND 85GHZ ON SSMIS 0133Z)
SYSTEM IS HOWEVER EXPECTED TO UNDERGO LESS FAVORABLE CONDITIONS AT UPPER
LEVELS AND EXPECTED TO WEAKEN ON COOLER SEA.

AVAILABLE DYNAMICAL GUIDANCE IS IN VERY GOOD AGREEMENT. UNDER THE
STEERING INFLUENCE OF A MID TO UPPER LEVEL RIDGE LOCATED EAST OF THE
SYSTEM, GAEL IS GOING TO KEEP ON SPEEDING UP SOUTH-SOUTHEASTWARDS WITHIN
THE NEXT 24 TO 36 HOURS IN A LESS AND LESS FAVOURABLE ENVIRONMENT
(NORTHWESTERLY WINDSHEAR S
TRONGER STARTING THIS COMING NIGHT AND THEN INSUFFICIENT OCEAN HEAT
POTENTIAL AS THE SSTS BECOME COOL) AND TO WEAK BEFORE BEGINNING ITS
EXTRATROPICAL TRANSITION.
AT THE END OF THE FORECAST RANGE, A BUILDING MID-LEVEL RIDGE FROM THE
SOUTHWEST COULD SLOW DOWN THE EXTRATROPICAL EXIT OF GAEL.

[Chacor]

WTIO30 FMEE 091227

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

0.A WARNING NUMBER : 31/8/20082009
1.A TROPICAL CYCLONE 8 (GAEL)

2.A POSITION 2009/02/09 AT 1200 UTC :
WITHIN 20 NM RADIUS OF POINT 29.5S / 57.5E
(TWENTY NINE DECIMAL FIVE DEGREES SOUTH AND FIFTY SEVEN DECIMAL FIVE
DEGREES EAST)
MOVEMENT : SOUTH-EAST 19 KT

3.A DVORAK ANALYSIS : 3.5/4.5 /W 1.0/12 H
4.A CENTRAL PRESSURE : 965 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 70 KT
RADIUS OF MAXIMUM WINDS (RMW) : 30 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 800 SE: 700 SO: 700 NO: 450
50 KT NE: 160 SE: 140 SO: 070 NO: 070

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1007 HPA / 950 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/02/10 00 UTC: 31.0S/59.0E, MAX WIND=060KT, BECOMING
EXTRATROPICAL.
24H: 2009/02/10 12 UTC: 32.0S/60.6E, MAX WIND=050KT, EXTRATROPICAL.
36H: 2009/02/11 00 UTC: 32.7S/62.5E, MAX WIND=040KT, EXTRATROPICAL.
48H: 2009/02/11 12 UTC: 33.5S/64.2E, MAX WIND=030KT, EXTRATROPICAL.
60H: 2009/02/12 00 UTC: 35.0S/66.8E, MAX WIND=040KT, EXTRATROPICAL.
72H: 2009/02/12 12 UTC: 37.6S/71.3E, MAX WIND=040KT, EXTRATROPICAL.

2.B OTHER INFORMATIONS:
T=3.5 AND CI=4.5+

GAEL HAS RAPIDLY WEAKEN UNDER THE EFFECT OF NORTH-WESTERLY UPPER LEVELS
VERTICAL WIND SHEAR AND HIS ARRIVAL OVER COOLER SEAS (24.5oC).
CONVECTION INTENSITY AND EXTENSION HAVE WEAKEN DURING THE LAST FEW HOURS
(CF. RECENT ANIMATED INFRA-RED IMAGERY). CONVECTION IS NOW SOUTH-EASTWARD
OF THE LLC (CF. MW IMAGERY NOAA17 AT 1010TU).
GAEL HAS ALSO BEGINING HIS EXTRA-TROPICAL TRANSITION BUT STRONG WINDS
REMAINS CLOSE TO THE LLC (TROPICAL FEATURES).
IT IS EXPECTED TO TRACK MORE SLOWLY SOUTH-EASTWARD DURING THE NEXT 48
HEURES, IN RELATION WITH THE SUBTROPICAL LOW LEVEL RIDGE IN THE
SOUTH-WEST OF THE SYSTEM.

[Crostorm]

640
WTIO30 FMEE 091819

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

0.A WARNING NUMBER : 32/8/20082009
1.A TROPICAL CYCLONE 8 (GAEL)

2.A POSITION 2009/02/09 AT 1800 UTC :
30.9S / 59.4E
(THIRTY DECIMAL NINE DEGREES SOUTH AND FIFTY NINE DECIMAL FOUR DEGREES
EAST)
MOVEMENT : SOUTH-EAST 20 KT

3.A DVORAK ANALYSIS : 3.5/4.5 /W 1.5/12 H
4.A CENTRAL PRESSURE : 970 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 65 KT
RADIUS OF MAXIMUM WINDS (RMW) : 30 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 400 SE: 550 SO: 550 NO: 400
50 KT NE: 150 SE: 150 SO: 220 NO: 100

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1010 HPA / 1300 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/02/10 06 UTC: 32.5S/61.5E, MAX WIND=050KT, EXTRATROPICAL.
24H: 2009/02/10 18 UTC: 33.0S/63.0E, MAX WIND=050KT, EXTRATROPICAL.
36H: 2009/02/11 06 UTC: 34.0S/64.5E, MAX WIND=040KT, EXTRATROPICAL.
48H: 2009/02/11 18 UTC: 35.3S/66.3E, MAX WIND=030KT, EXTRATROPICAL.
60H: 2009/02/12 06 UTC: 37.2S/68.3E, MAX WIND=020KT, EXTRATROPICAL.
72H: 2009/02/12 18 UTC: 39.1S/72.2E FILLING UP.

2.B OTHER INFORMATIONS:
T=3.5 AND CI=4.5
FIX EXTRAPOLATED FROM THE F16/1635Z CENTRE POSITION.
WINDS EXTENSION CALIBRATED THANKS TO QUIKSCAT DATA AT 1346Z.
GAEL IS WEAKENING UNDER THE EFFECT OF NORTHWESTERLY UPPER LEVELS VERTICAL
WINDSHEAR AND HIS ARRIVAL OVER COOLER SEAS (23oC).
DEEP CONVECTION IS SOUTHEASTWARDS AWAY FROM THE LLCC (TRMM 1315Z, F16
1635Z) DUE TO THIS VERTICAL WINDSHEAR.
GAEL HAS ALSO BEGUN HIS EXTRATROPICAL TRANSITION BUT STRONG WINDS REMAIN
CLOSE TO THE LLCC.
IT IS EXPECTED TO TRACK MORE SLOWLY SOUTH-EASTWARD DURING THE NEXT 24 TO
36 HEURES, IN RELATION WITH THE SUBTROPICAL HIGH PRESSURES BUILDING IN
THE SOUTHWEST OF THE SYSTEM.

[Crostorm]

[HURAKAN]

Going fast.

[HURAKAN]

[Crostorm]

434
WTIO30 FMEE 100015

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

0.A WARNING NUMBER : 33/8/20082009
1.A SEVERE TROPICAL STORM 8 (GAEL)

2.A POSITION 2009/02/10 AT 0000 UTC :
WITHIN 20 NM RADIUS OF POINT 31.4S / 60.6E
(THIRTY ONE DECIMAL FOUR DEGREES SOUTH AND SIXTY DECIMAL SIX DEGREES EAST
)
MOVEMENT : EAST-SOUTH-EAST 15 KT

3.A DVORAK ANALYSIS : 3.0/4.0 /W 2.5/24 H
4.A CENTRAL PRESSURE : 975 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 60 KT
RADIUS OF MAXIMUM WINDS (RMW) : 30 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 350 SE: 500 SO: 500 NO: 350
50 KT NE: 120 SE: 180 SO: 180 NO: 060

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1010 HPA / 1200 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/02/10 12 UTC: 32.0S/62.4E, MAX WIND=050KT, EXTRATROPICAL.
24H: 2009/02/11 00 UTC: 32.7S/64.0E, MAX WIND=040KT, EXTRATROPICAL.
36H: 2009/02/11 12 UTC: 33.6S/65.3E, MAX WIND=030KT, EXTRATROPICAL.
48H: 2009/02/12 00 UTC: 35.5S/67.0E, MAX WIND=020KT, EXTRATROPICAL.
60H: 2009/02/12 12 UTC: 37.8S/69.6E FILLING UP.


2.B OTHER INFORMATIONS:
T=3.0 AND CI=4.0+
FIX EXTRAPOLATED FROM THE N18/2130Z CENTRE POSITION.
GAEL IS WEAKENING UNDER THE EFFECT OF NORTHWESTERLY UPPER LEVELS VERTICAL
WINDSHEAR AND HIS ARRIVAL OVER COOLER SEAS (23oC).
DEEP CONVECTION IS SOUTHEASTWARDS AWAY FROM THE LLCC (F16/1635Z,
AMSU/2130Z) DUE TO THIS VERTICAL WINDSHEAR.
IT IS EXPECTED TO TRACK SLOWLIER SOUTHEASTWARDS DURING THE NEXT 36 HEURES
, IN RELATION WITH THE SUBTROPICAL HIGH PRESSURES IN THE SOUTH OF THE
SYSTEM.

[HURAKAN]

WTXS31 PGTW 100300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 13S (GAEL) WARNING NR 016//
RMKS/
1. TROPICAL CYCLONE 13S (GAEL) WARNING NR 016
02 ACTIVE TROPICAL CYCLONES IN SOUTH IO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
100000Z --- NEAR 32.0S 61.4E
MOVEMENT PAST SIX HOURS - 125 DEGREES AT 20 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 205 NM NORTHEAST QUADRANT
205 NM SOUTHEAST QUADRANT
165 NM SOUTHWEST QUADRANT
140 NM NORTHWEST QUADRANT
REPEAT POSIT: 32.0S 61.4E
---
FORECASTS:
12 HRS, VALID AT:
101200Z --- 34.2S 64.7E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
185 NM SOUTHEAST QUADRANT
155 NM SOUTHWEST QUADRANT
145 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 135 DEG/ 16 KTS
---
24 HRS, VALID AT:
110000Z --- 36.4S 67.4E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
100300Z POSITION NEAR 32.6S 62.2E.
TROPICAL CYCLONE (TC) 13S (GAEL), LOCATED APPROXIMATELY 720 NM
SOUTH-SOUTHEAST OF LA REUNION HAS TRACKED SOUTHEASTWARD AT 20 KNOTS
OVER THE PAST SIX HOURS. ANIMATED WATER VAPOR IMAGERY SHOWS TC 13S
HAS INCREASED ITS FORWARD MOTION AND CONVECTION AROUND THE LOW LEVEL
CIRCULATION CENTER HAS SIGNIFICANTLY DECREASED. CURRENT CENTRAL WIND
SPEED AND POSITION ARE BASED ON SATELLITE INTENSITY FIXES FROM PGTW
AND FMEE AND ANIMATED INFRARED SATELLITE IMAGERY. ENVIRONMENTAL
ANALYSIS INDICATES THE SYSTEM HAS RAPIDLY TRACKED INTO AN AREA OF
STRONG VERTICAL WIND SHEAR AND COOLER SEA SURFACE TEMPERATURES. THE
CYCLONE IS EXPECTED TO TRANSITION INTO A COLD CORE SYSTEM OVER THE
NEXT 12 HOURS AS IT GETS ABSORBED INTO THE BAROCLINIC ZONE. THIS IS
THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WARNING CENTER
(NAVMARFCSTCEN). THE SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF
REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 100000Z IS 20 FEET.
REFER TO TROPICAL CYCLONE 14S (FREDDY) FINAL WARNING (WTXS32 PGTW).//

[HURAKAN]

WTIO30 FMEE 070023 RRB
GAEL BENEFIT FROM A GOOD TRADE INFLOW THANKS TO THE SUBTROPICAL HIGH
PRESSURE IN ITS SOUTH-WEST. BUT THE MONSOON FLOW WAS CLEARELY CUT
DURING
THE LAST HOURS : EROSION OF THE CDO IN THE NORTH-WESTERN QUADRANT
(CF.
TRMM AT 17.41UTC AND AQUA AT 21.41UTC).
HOWEVER UPPER ENVIRONMENT IS BECOMING VERY FAVOURABLE WITH A GOOD
POLEWARD OUTFLOW WITHIN THE NEXT 12 HOURS WITH AN INTERACTION WITH
THE
NORTHWESTERLY SUBTROPICAL JET LOCATED SOUTH OF MADAGASCAR. MAXIMAL
INTENSITY SHOULD BE REACH WITHIN THE NEXT HOURS BEFORE COOLER SST AND
A
STRONGER NORTHWESTERLY V
ERTICAL WINDSHEAR STARTING SUNDAY NIGHT.
GAEL TRACKS UNDER THE STEERING FLOW OF AN UPPER LEVEL RIDGE PRESENT
IN
THE SOUTHEAST OF THE SYSTEM. IT IS EXPECTED TO RECURVE ONCE MORE
PROGRESSIVELY TOWARDS THE SOUTH, THEN SOUTHSOUTHEASTWARDS SUNDAY.=

[Chacor]

HURAKAN... always look at the timestamp.

That advisory is a re-transmission of one sent 07 February at 0023 UTC.