SWIO: BENILDE - Severe Tropical Storm

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Chacor
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SWIO: BENILDE - Severe Tropical Storm

#1 Postby Chacor » Mon Dec 26, 2011 7:16 pm

AN AREA OF CONVECTION HAS PERSISTED NEAR 8.1S 94.6E,
APPROXIMATELY 220 NM NORTHWEST OF THE COCOS ISLANDS OVER THE PAST 24
HOURS. ANIMATED INFRARED SATTELITE IMAGERY SHOWS A DISORGANIZED AREA
OF CONSOLIDATING DEEP CONVECTION SURROUNDING AN ELONGATED LOW LEVEL
CIRCULATION CENTER (LLCC). LOW LEVEL STREAMLINE ANALYSIS CONFIRMS
THE LLCC, AND SHOWS THAT THE SYSTEM IS EMBEDDED WITHIN THE MONSOON
TROUGH. UPPER LEVEL ANALYSIS INDICATES THAT THE SYSTEM LIES IN A
DIFFLUENT AREA, 5 DEGREES NORTH OF THE SUBTROPICAL RIDGE AXIS, WITH
MODERATE (15 TO 25 KNOT) VERTICAL WIND SHEAR. SEA SURFACE
TEMPERATURES IN THE AREA ARE APPROXIMATELY 28 DEGREES CELSIUS.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. DUE TO
THE DISORGANIZED CONVECTION THE POTENTIAL FOR THE DEVELOPMENT OF A
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

Perth do not expect much to come of this before it moves into MF's area...
Potential Cyclones:
At midday WST a tropical low was located near 11S 091E and may linger near the
western boundary of the Western region before moving west of the region on
Thursday. The low is not expected to develop into a tropical cyclone in the
Western region.

Likelihood of this low becoming a tropical cyclone in the Western Region:
Tuesday :Moderate
Wednesday :Low
Thursday :Low
Last edited by Chacor on Sun Jan 01, 2012 3:47 pm, edited 6 times in total.
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#2 Postby Grifforzer » Tue Dec 27, 2011 10:16 pm

Reunion Tropical Cyclone Outlook


East of 80E, the westerlies feed two tropical systems located both north and south of the equator: A "tropical storm THANE" (according to the 06Z advisory from RSMC New Delhi) located in the southern Gulf of Bengal and a 1003 hPa low, very approximately located near 11S 94E at 0900Z close to the northern boundary of the Australian area of responsibility.

Currently, the near equatorial westerlies mainly feeds the northern hemisphere disturbance. But up
to Thursday, this pattern should gradually turn towards a feeding of the southern hemisphere low
(according to all available guidance). Consequently, a slow development of this system appears likely as it should move on a generally west southwestwards track on the northern edge of the subtropical ridge. However, some easterly shear should maintain, beginning to weaken up to Thursday. This low is expected to enter within our area of responsibility at the end of Wednesday or during the Wednesday to Thursday night.

For the next 24 hours, the potential for development of a tropical depression is poor, with the arrival of the tropical perturbation in the process of formation in the Australian area . The potential becomes poor to fair Thursday over the eastern part of the basin, and fair to good on Friday.
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#3 Postby Grifforzer » Wed Dec 28, 2011 3:44 am

RSMC Reunion
Tropical Cyclone Advisory #1
PERTURBATION TROPICALE 04-20112012
10:00 AM RET December 28 2011
===================================

At 10:00 AM RET, Tropical Disturbance 04-20112012 (1000 hPa) located at 12.2S 89.4E has 10 minute sustained winds of 25 knots with gusts of 40 knots. The disturbance is reported as moving west at 16 knots.

Dvorak Intensity: T2.0/2.0/S0.0/0 HRS

12 HRS: 12.2S 87.4E - 30 knots (Depression Tropicale)
24 HRS: 12.5S 85.0E - 40 knots (Tempête Tropicale Moderée)
48 HRS: 13.0S 80.6E - 50 knots (Forte Tempête Tropicale)
72 HRS: 14.1S 76.9E - 60 knots (Forte Tempête Tropicale)

Convection persists and moved closer from the center since yesterday (1300z). System is undergoing a moderate easterly vertical wind shear. Low level circulation center has accelerated westward within the last few hours.

Lower level environmental conditions are favorable. Upper level conditions should improve within the next 48 hours. Upper level wind shear should weaken progressively. Beyond 48 hours, and upper level outflow channel should set up poleward. Intensification should remain moderate within the next 48 hours and accelerate beyond 48 hours. Available numerical weather prediction models are in good agreement for a west to southwestward track over the northern edge of the subtropical high pressure of low and mid-troposphere.
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#4 Postby HURAKAN » Wed Dec 28, 2011 8:02 am

Image

WTXS32 PGTW 280900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 04S (FOUR) WARNING NR 001//
REF/A/MSG/NAVMARFCSTCEN PEARL HARBOR HI/280152ZDEC2011//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. TROPICAL CYCLONE 04S (FOUR) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
280600Z --- NEAR 12.1S 89.6E
MOVEMENT PAST SIX HOURS - 265 DEGREES AT 16 KTS
POSITION ACCURATE TO WITHIN 060 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: 12.1S 89.6E
---
FORECASTS:
12 HRS, VALID AT:
281800Z --- 12.1S 87.4E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 265 DEG/ 11 KTS
---
24 HRS, VALID AT:
290600Z --- 12.3S 85.1E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 265 DEG/ 11 KTS
---
36 HRS, VALID AT:
291800Z --- 12.5S 82.8E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 260 DEG/ 11 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
300600Z --- 12.9S 80.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 255 DEG/ 08 KTS
---
72 HRS, VALID AT:
310600Z --- 13.8S 77.5E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 240 DEG/ 07 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
010600Z --- 15.3S 74.9E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 220 DEG/ 06 KTS
---
120 HRS, VALID AT:
020600Z --- 17.2S 73.3E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
280900Z POSITION NEAR 12.1S 89.1E.
TROPICAL CYCLONE (TC) 04S, LOCATED APPROXIMATELY 1050 NM EAST-
SOUTHEAST OF DIEGO GARCIA, HAS TRACKED WESTWARD AT 16 KNOTS OVER THE
PAST SIX HOURS. TC 04S HAS CONSOLIDATED OVER THE PAST 12 HOURS WITH
A LARGE CLUSTER OF DEEP CONVECTION PERSISTING OVER THE WESTERN SEMI-
CIRCLE OF A PARTIALLY-EXPOSED, WELL-DEFINED LOW-LEVEL CIRCULATION
CENTER (LLCC). THIS CONSOLIDATION IS EVIDENT IN THE TOTAL
PRECIPITABLE WATER LOOP WHICH SHOWS AN ENVELOPE OF DEEP MOISTURE
ASSOCIATED WITH THE SYSTEM. THE UPPER-LEVEL ENVIRONMENT IS CURRENTLY
MARGINAL WITH AN ANTICYCLONE DISPLACED TO THE SOUTHEAST PRODUCING
EASTERLY, DIFFLUENT FLOW AND MODERATE (20-25 KNOTS) VERTICAL WIND
SHEAR (VWS). BASED ON MULTISPECTRAL SATELLITE IMAGERY AND A 280313Z
METOP-A IMAGE, THE LLCC HAS STRENGTHENED AND THE CURRENT INTENSITY
IS ASSESSED AT 35 KNOTS; HOWEVER, DATA HAS BEEN SPARSE AND A 280315Z
ASCAT IMAGE SHOWED ONLY 20-25 KNOT WINDS OVER THE WESTERN SEMI-
CIRCLE. DVORAK ESTIMATES HAVE INCREASED TO 35 KNOTS FROM BOTH KNES
AND PGTW AND PROVIDED JUSTIFICATION FOR THE 35-KNOT ASSESSMENT AND
INITIAL WARNING. THERE IS FAIR CONFIDENCE IN THE CURRENT POSITION
BASED ON THE METOP-A IMAGE AND MSI. TC 04S IS FORECAST TO TRACK
WESTWARD UNDER THE LOW-LEVEL SUBTROPICAL RIDGE (STR) TO THE SOUTH
BUT SHOULD TRACK MORE WEST-SOUTHWESTWARD AFTER TAU 36 AS IT
STRENGTHENS AND TRACKS TOWARD A DEVELOPING WEAKNESS IN THE STR
CREATED BY AN APPROACHING SHORT-WAVE TROUGH. MODEL GUIDANCE IS IN
TIGHT AGREEMENT EXCEPT FOR WBAR WHICH INDICATES VERY SLOW TRACK
SPEEDS, THEREFORE, THIS FORECAST IS POSITIONED FASTER THAN THE MODEL
CONSENSUS. THE GREATEST UNCERTAINTY IN THIS FORECAST DEALS WITH THE
INTENSITY FORECAST. BOTH GFDN AND STIPS GUIDANCE INDICATES A PEAK
INTENSITY OF 90 KNOTS, HOWEVER, THE MAJORITY OF MODEL GUIDANCE SHOWS
AN ANTICYCLONE OVER THE SYSTEM, WHICH AS MENTIONED, IS NOT
OCCURRING. THEREFORE, THE INTENSITY TREND IS EXPECTED TO BE FLAT
THROUGH TAU 36 UNTIL THE VWS DECREASES. TC 04S IS EXPECTED TO
INTENSIFY AT A GREATER RATE AFTER TAU 36 DUE TO IMPROVED POLEWARD
OUTFLOW ASSOCIATED WITH THE APPROACHING UPPER-LEVEL TROUGH WITH A
PEAK INTENSITY OF 70 KNOTS BY TAU 96. AFTER TAU 96, THE SYSTEM IS
FORECAST TO WEAKEN AS IT ENCOUNTERS AN UPPER-LEVEL TROUGH AND
INCREASING VWS AND CONVERGENCE ALOFT. THIS WARNING SUPERSEDES AND
CANCELS REF A, NAVMARFCSTCEN 280152Z DEC 12 TROPICAL CYCLONE
FORMATION ALERT (WTXS22 PGTW 280200). MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 280600Z IS 10 FEET. NEXT WARNINGS AT 282100Z AND 290900Z.//
NNNN
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#5 Postby Chacor » Wed Dec 28, 2011 8:35 am

WTIO30 FMEE 281251
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 2/4/20112012
1.A TROPICAL DISTURBANCE 4
2.A POSITION 2011/12/28 AT 1200 UTC:
WITHIN 20 NM RADIUS OF POINT 12.1 S / 88.9 E
(TWELVE DECIMAL ONE DEGREES SOUTH AND EIGHTY EIGHT DECIMAL
NINE DEGREES EAST)
MOVEMENT : WEST 10 KT
3.A DVORAK ANALYSIS: 2.0/2.0/S 0.0/6 H
4.A CENTRAL PRESSURE: 1000 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 25 KT
RADIUS OF MAXIMUM WINDS (RMW) :NIL
6.A EXTENSION OF WIND BY QUADRANTS (KM):
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1005 HPA / 600 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : MEDIUM
1.B FORECASTS:
12H: 2011/12/29 00 UTC: 12.0 S / 86.6 E, MAX WIND=030 KT, TROPICAL
DEPRESSION
24H: 2011/12/29 12 UTC: 12.4 S / 84.5 E, MAX WIND=035 KT, MODERATE
TROPICAL STORM
36H: 2011/12/30 00 UTC: 12.8 S / 82.2 E, MAX WIND=040 KT, MODERATE
TROPICAL STORM
48H: 2011/12/30 12 UTC: 13.3 S / 79.6 E, MAX WIND=050 KT, SEVERE
TROPICAL STORM
60H: 2011/12/31 00 UTC: 14.0 S / 78.0 E, MAX WIND=060 KT, SEVERE
TROPICAL STORM
72H: 2011/12/31 12 UTC: 14.6 S / 76.5 E, MAX WIND=070 KT, TROPICAL
CYCLONE
2.B LONGER-RANGE OUTLOOK :
96H: 2012/01/01 12 UTC: 16.3 S / 74.6 E, MAX WIND=085 KT, TROPICAL
CYCLONE
120H: 2012/01/02 12 UTC: 17.2 S / 72.0 E, MAX WIND=080 KT, TROPICAL
CYCLONE
2.C ADDITIONAL INFORMATIONS:
T=CI=2.0+
THE CLOUD PATTERN OF THE DISTURBANCE HAS LITTLE CHANGED WITHIN THE
LAST 6 HOURS. THE LOW LEVEL CIRCULATION IS STILL ON THE EASTERN
BORDER OF THE CLOUD MASS OF DEEP CONVECTION. THE LLCC HAS BEEN
RELOCATED AT 06Z (CORRECTIVE POSITION AT 06Z : NEAR 12.3S/89.9E). THE
LOW LEVEL CIRCULATION CENTER HAS SLOWED DOWN. THE LOW LEVEL FLOW
PATTERN SEEMS TO BE RATHER ILL-DEFINED (CF. TRMM 37GHZ AT 09.31Z).
LOWER LEVELS SUPPLY IS CURRENTLY GOOD ON THE TWO FACES OF THE SYSTEM.
ENEGETIC POTENTIAL IS GOOD.
SYSTEM IS STILL UNDERGOING A MODERATE UPPER LEVEL EAST VERTICAL WIND
SHEAR.
THE UPPER LEVELS CONSTRAINT SHOULD PROGRESSIVELY WEAKEN WITHIN THE
NEXT 36 TO 48 HOURS.
AT 48 TAU, AN UPPER OUTFLOW CHANNEL SHOULD SET UP POLEWARD. A SECOND
UPPER OUTFLOW SHOULD TEMPORARILY SET UP EQUATORWARD ON SATURDAY AND
SUNDAY.
INTENSIFICATION SHOULD ALSO REMAIN MODERATE WITHIN THE NEXT 36 HOURS,
BUT SHOULD HEIGHTEN BEYOND. AT THE END OF THE FORECAST RANGE
(BEGINNING OF NEXT WEEK) UPPER LEVELS ENVIRONMENTAL CONDITIONS SHOULD
BECOME LESS FAVOURABLE (STRENGTHENING OF THE UPPER LEVEL WIND SHEAR).
AVALAIBLE NWP MODELS ARE IN GOOD AGREEMENT FOR A WEST TO SOUTH-WEST
TRACK, OVER THE NORTHERN PERIPHERY OF THE SUBTROPICAL HIGH PRESSURES
OF LOW AND MID-TROPOSPHERE.=
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#6 Postby Grifforzer » Wed Dec 28, 2011 2:28 pm

Tropical Cyclone Advisory #3
DEPRESSION TROPICALE 04-20112012
22:00 PM RET December 28 2011
===================================

At 22:00 PM RET, Tropical Depression 04 (999 hPa) located at 12.0S 87.6E has 10 minute sustained winds of 30 knots with gusts of 45 knots. The depression is reported as moving west at 12 knots.

Dvorak Intensity: T2.5/2.5/S0.5/18 HRS

Near Gale Force Winds
90 NM radius from the center extending up to 150 NM in the southwestern semi-circle

12 HRS: 12.2S 85.5E - 35 knots (Tempête Tropicale Moderée)
24 HRS: 12.5S 83.2E - 40 knots (Tempête Tropicale Moderée)
48 HRS: 13.4S 79.2E - 50 knots (Forte Tempête Tropicale)
72 HRS: 14.9S 76.0E - 65 knots (CYCLONE Tropical)

The cloud pattern of the disturbance has little changed, the low level circulation is still on the eastern border of the cloud mass of deep convection. The low level flow pattern seems to be rather ill-defined. (CF SSMIS 37ghz at 14:00 PM UTC). Lower levels supply is currently good on the two faces of the system. However, system is still undergoing a moderate upper level east vertical wind shear.

The upper level constraint should progressively weaken within the next 36-48 hours. At 48 hours, an upper outflow channel should set up poleward. A second upper outflow should temporarily set up equatorward on Saturday and Sunday. Intensification should also remain moderate within the next 36 hours, but should heighten beyond. At the end of the forecast range (beginning of next week) upper level environmental conditions should become less favorable (strengthening of the upper level wind shear).

Available numerical weather prediction models are in good agreement for a west to southwestward track over the northern periphery of the subtropical high pressure and low and mid-troposphere.
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#7 Postby Chacor » Thu Dec 29, 2011 4:31 am

WTIO30 FMEE 290632
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 5/4/20112012
1.A TROPICAL DEPRESSION 4
2.A POSITION 2011/12/29 AT 0600 UTC:
WITHIN 10 NM RADIUS OF POINT 12.8 S / 85.5 E
(TWELVE DECIMAL EIGHT DEGREES SOUTH AND EIGHTY FIVE DECIMAL FIVE DEGREES EAST)
MOVEMENT : WEST 13 KT
3.A DVORAK ANALYSIS: 2.5/2.5/S 0.0/12 H
4.A CENTRAL PRESSURE: 999 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 30 KT
RADIUS OF MAXIMUM WINDS (RMW) :NIL
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 40 SE: 60 SW: 60 NW: 40
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1008 HPA / 1100 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : MEDIUM
1.B FORECASTS:
12H: 2011/12/29 18 UTC: 13.0 S / 82.8 E, MAX WIND=030 KT, TROPICAL DEPRESSION
24H: 2011/12/30 06 UTC: 13.3 S / 80.7 E, MAX WIND=035 KT, MODERATE TROPICAL STORM
36H: 2011/12/30 18 UTC: 13.8 S / 79.3 E, MAX WIND=040 KT, MODERATE TROPICAL STORM
48H: 2011/12/31 06 UTC: 14.7 S / 78.0 E, MAX WIND=050 KT, SEVERE TROPICAL STORM
60H: 2011/12/31 18 UTC: 15.8 S / 76.8 E, MAX WIND=060 KT, SEVERE TROPICAL STORM
72H: 2012/01/01 06 UTC: 16.8 S / 75.8 E, MAX WIND=065 KT, TROPICAL CYCLONE
2.B LONGER-RANGE OUTLOOK :
96H: 2012/01/02 06 UTC: 19.1 S / 74.2 E, MAX WIND=080 KT, TROPICAL CYCLONE
120H: 2012/01/03 06 UTC: 19.9 S / 73.1 E, MAX WIND=065 KT, TROPICAL CYCLONE
2.C ADDITIONAL INFORMATIONS:
T=CI=2.5-
SYSTEM KEEPS ON UNDERGOING AN EASTERLY VERTICAL WINDSHEAR CONSTRAINT ON THE NORTHWESTERN EDGE OF THE UPPER LEVEL RIDGE.
THE LOW LEVEL CIRCULATION IS PARTIALLY EXPOSED EAST OF THE MAIN DEEP CONVECTIVE ACTIVITY.
LOW LEVEL INFLOW IS GOOD POLEWARD ET IS CURRENTLY IMPROVING EQUATORWARD.
EQUATORIAL WESTERLIES ARE NO LONGER MAINLY FEEDING THE NORTHERN HEMISPHERE SYSTEM IN THE GULF OF BENGAL (THANE) AND IS
BECOMING MORE DIRECT TOWARDS OUR SWIO SYSTEM DT NR4. IT IS EXPECTED TO KEEP ON IMPROVING WITHIN THE NEXT DAYS ON THIS
EQUATOR SIDE.
VERTICAL WINDSHEAR IS EXPECTED TO PROGRESSIVELY RELAX AND ENVIRONMENTAL CONDITIONS ARE EXPECTED TO CONSEQUENTLY BECOME
MORE FAVOURABLE FOR FURTHER INTENSIFICATION ON AND AFTER SATURDAY AS TWO UPPER LEVEL OUTLOW CHANNELS BUILD ALOFT ON THE
BOTH SIDES IN THE SAME TIME.
AVALAIBLE NWP MODELS ARE IN GOOD AGREEMENT FOR A WESTWARDS TRACK OVER THE NORTHERN EDGE OF THE SUBTROPICAL HIGH PRESSURES
WITHIN LOW-LEVELS AND MID-LEVELS, THEN MORE SOUTH-WESTWARDS TRACK UNDER THE COMBINED EFFECTS OF A FORECAST WEAKENESS IN
THE LOW-LEVEL SUBTROPICAL HIGH PRESSURES (IN RELATIONSHIP WITH A TRANSITING POLAR THROUGH), AND OF THE STEERING INFLUENCE OF A
BUILDING RIDGE EAST OF THE SYSTEM IN THE MID-LEVELS.
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#8 Postby Chacor » Thu Dec 29, 2011 4:32 am

JTWC forecasting a 90 kt peak:

WTXS32 PGTW 290900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 04S (FOUR) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 04S (FOUR) WARNING NR 003
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
290600Z --- NEAR 12.7S 85.5E
MOVEMENT PAST SIX HOURS - 265 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 040 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: 12.7S 85.5E
---
FORECASTS:
12 HRS, VALID AT:
291800Z --- 12.8S 82.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 260 DEG/ 11 KTS
---
24 HRS, VALID AT:
300600Z --- 13.1S 80.6E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 250 DEG/ 08 KTS
---
36 HRS, VALID AT:
301800Z --- 13.7S 79.0E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 235 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
310600Z --- 14.5S 77.8E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 220 DEG/ 06 KTS
---
72 HRS, VALID AT:
010600Z --- 16.4S 76.0E
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 210 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
020600Z --- 18.1S 74.9E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 220 DEG/ 04 KTS
---
120 HRS, VALID AT:
030600Z --- 19.4S 73.7E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
290900Z POSITION NEAR 12.7S 84.8E.
TROPICAL CYCLONE (TC) 04S, LOCATED APPROXIMATELY 830 NM EAST-
SOUTHEAST OF DIEGO GARCIA, HAS TRACKED WESTWARD AT 10 KNOTS OVER THE
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
DEPICTS A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH
THE BULK OF THE DEEP CONVECTION CONFINED TO THE WESTERN SEMI-CIRCLE
DUE TO MODERATE, EASTERLY VERTICAL WIND SHEAR (VWS). OVER THE PAST
12 HOURS, THERE HAS BEEN A SLIGHT INCREASE IN ORGANIZATION WITH
MULTIPLE CONVECTIVE BANDS WRAPPING WEAKLY INTO THE CENTER. A 282347Z
CORIOLIS IMAGE DEPICTED A BROAD LLCC WITH TIGHTLY-CURVED SHALLOW
BANDING AND RECENT ASCAT SHOWS A BROAD WIND FIELD WITH 20-25 KNOT
WINDS AROUND THE PERIPHERY. THE UPPER-LEVEL ENVIRONMENT REMAINS
MARGINAL DUE TO THE POSITION OF THE ANTICYCLONE TO THE SOUTHEAST,
WHICH IS PRODUCING THE MODERATE VWS. BASED ON THE BROAD LLCC AND
MARGINAL ENVIRONMENT, THE SYSTEM IS EXPECTED TO INTENSIFY SLOWLY
THROUGH TAU 36. THERE IS GOOD CONFIDENCE IN THE CURRENT POSITION AND
THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES OF 35 KNOTS FROM
KNES AND PGTW. TC 04S IS FORECAST TO TRACK WESTWARD TO WEST-
SOUTHWESTWARD THROUGH TAU 36 UNDER THE LOW-LEVEL SUBTROPICAL RIDGE
(STR) POSITIONED SOUTH. AFTER TAU 36, TC 04S IS EXPECTED TO TURN
SOUTHWESTWARD TOWARD A WEAKNESS IN THE STR CREATED BY AN
APPROACHING, DEEP MIDLATITUDE SHORTWAVE TROUGH, WHICH WILL LEAD TO A
DECREASE IN VWS AND IMPROVED POLEWARD OUTFLOW. THEREFORE, THE SYSTEM
IS FORECAST TO INTENSIFY AT A FASTER RATE TO A PEAK INTENSITY OF 90
KNOTS BY TAU 72. MODEL GUIDANCE IS IN TIGHT AGREEMENT THROUGH TAU
72. IN THE EXTENDED PERIOD, TC 04S WILL SLOW AS IT ENCOUNTERS
INCREASING VWS AND CONVERGENCE ALOFT ASSOCIATED WITH THE
AFOREMENTIONED TROUGH AND WILL WEAKEN. MODEL GUIDANCE DIVERGES AFTER
TAU 72 WITH INCREASED UNCERTAINTY IN THE TRACK. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 290600Z IS 15 FEET. NEXT WARNINGS AT 292100Z AND
300900Z.//
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#9 Postby hurricane25 » Thu Dec 29, 2011 8:22 am

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.


I disagree with the current intensity of the JTWC as it appears to be around 50-55 knots, but certainly agree with there longer term thinking of this cyclone. 04s has "ok" outflow and appears to have developed a well defined core structure that screams strengthening at least within my opinion. Not to say that shear couldn't get to it later on and a RIC is a lock, but I'd say it's a possibility. A Major cyclone(100-110 knots) is quite likely. Quite likely is 60 percent within my opinion.
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#10 Postby Chacor » Thu Dec 29, 2011 10:12 am

WTIO30 FMEE 291236
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 6/4/20112012
1.A TROPICAL DEPRESSION 4
2.A POSITION 2011/12/29 AT 1200 UTC:
WITHIN 20 NM RADIUS OF POINT 12.9 S / 84.2 E
(TWELVE DECIMAL NINE DEGREES SOUTH AND EIGHTY FOUR DECIMAL
TWO DEGREES EAST)
MOVEMENT : WEST 11 KT
3.A DVORAK ANALYSIS: 2.5/2.5/D 0.5/24 H
4.A CENTRAL PRESSURE: 999 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 30 KT
RADIUS OF MAXIMUM WINDS (RMW) :56 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 60 SE: 110 SW: 110 NW: 60
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1007 HPA / 1100 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : MEDIUM
1.B FORECASTS:
12H: 2011/12/30 00 UTC: 13.3 S / 82.1 E, MAX WIND=035 KT, MODERATE
TROPICAL STORM
24H: 2011/12/30 12 UTC: 13.8 S / 80.0 E, MAX WIND=040 KT, MODERATE
TROPICAL STORM
36H: 2011/12/31 00 UTC: 14.5 S / 78.6 E, MAX WIND=045 KT, MODERATE
TROPICAL STORM
48H: 2011/12/31 12 UTC: 15.4 S / 77.5 E, MAX WIND=050 KT, SEVERE
TROPICAL STORM
60H: 2012/01/01 00 UTC: 16.3 S / 76.7 E, MAX WIND=060 KT, SEVERE
TROPICAL STORM
72H: 2012/01/01 12 UTC: 17.3 S / 76.0 E, MAX WIND=070 KT, TROPICAL
CYCLONE
2.B LONGER-RANGE OUTLOOK :
96H: 2012/01/02 12 UTC: 19.5 S / 74.9 E, MAX WIND=080 KT, TROPICAL
CYCLONE
120H: 2012/01/03 12 UTC: 21.1 S / 74.3 E, MAX WIND=060 KT, SEVERE
TROPICAL STORM
2.C ADDITIONAL INFORMATIONS:
T=CI=2.5-
SINCE FEW HOURS, CONVECTIVE ACTIVITY HAS BEEN CONSOLIDATING NEAR THE
LOW LEVEL CENTER BUT REMAINS CURRENTLY FLUCTUATING.
RECENT SATELLITE IMAGERY (METEOSAT7 AND SSMI F15 29/1103Z) DON'T SHOW
CONTINUOUS BAND WRAPPING MORE THAN 3 TENS AROUND THE CENTER.
EASTERLY WINDSHEAR BEGINS TO RELAX.
EQUATORIAL WESTERLIES ARE NO LONGER MAINLY FEEDING THE NORTHERN
HEMISPHERE SYSTEM IN THE GULF OF BENGAL (THANE) AND IS BECOMING MORE
DIRECT TOWARDS OUR SWIO SYSTEM DT NR4. IT IS EXPECTED TO KEEP ON
IMPROVING WITHIN THE NEXT DAYS ON THIS EQUATOR SIDE.
LOW LEVEL INFLOW IS GOOD POLEWARD.
SYSTEM IS EXPECTED TO KEEP ON INTENSIFY SLOWLY ON FRIDAY THEN MORE
CLEARLY ON AND AFTER SATURDAY AS IT TRACKS UNDER THE UPPER LEVEL
RIDGE AND AS TWO UPPER LEVEL OUTLOW CHANNELS BUILD ALOFT ON THE BOTH
SIDES IN THE SAME TIME.
IT IS EXPECTED TO REACH ITS MAXIMUM OF INTENSITY ON MONDAY BEFORE
UNDERGOING BACK AN UPPER LEVEL CONSTRAINT (WEST-NORTH-WESTERLY
WINDSHEAR) AND OVER LESS HEAT OCEANIC CONTENT.
AVALAIBLE NWP MODELS KEEP ON BEEING IN GOOD AGREEMENT FOR A
WEST-SOUTHWESTWARDS TRACK OVER THE NORTHERN EDGE OF THE SUBTROPICAL
HIGH PRESSURES WITHIN LOW-LEVELS AND MID-LEVELS, THEN MORE
SOUTH-WESTWARDS TRACK UNDER THE COMBINED EFFECTS OF A FORECAST
WEAKENESS IN THE LOW-LEVEL SUBTROPICAL HIGH PRESSURES (IN
RELATIONSHIP WITH A TRANSITING POLAR THROUGH), AND OF THE STEERING
INFLUENCE OF A BUILDING RIDGE EAST OF THE SYSTEM IN THE MID-LEVELS.=
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Re: SWIO: 04R - Tropical Depression (JTWC: TC 04S)

#11 Postby P.K. » Thu Dec 29, 2011 2:39 pm

WTIO30 FMEE 291919

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

0.A WARNING NUMBER: 7/4/20112012
1.A MODERATE TROPICAL STORM 4 (BENILDE)

2.A POSITION 2011/12/29 AT 1800 UTC:
WITHIN 30 NM RADIUS OF POINT 13.7 S / 82.9 E
(THIRTEEN DECIMAL SEVEN DEGREES SOUTH AND EIGHTY TWO DECIMAL NINE DEGREES EAST)
MOVEMENT : WEST-SOUTH-WEST 13 KT

3.A DVORAK ANALYSIS: 2.5/2.5/D 0.5/6 H
4.A CENTRAL PRESSURE: 996 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 35 KT
RADIUS OF MAXIMUM WINDS (RMW) :56 KM

6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 130 SE: 170 SW: 170 NW: 110
34 KT NE: 70 SE: 90 SW: 90 NW: 70



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1006 HPA / 900 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP

1.B FORECASTS:
12H: 2011/12/30 06 UTC: 14.3 S / 80.9 E, MAX WIND=040 KT, MODERATE TROPICAL STORM
24H: 2011/12/30 18 UTC: 15.2 S / 78.9 E, MAX WIND=045 KT, MODERATE TROPICAL STORM
36H: 2011/12/31 06 UTC: 15.9 S / 77.7 E, MAX WIND=050 KT, SEVERE TROPICAL STORM
48H: 2011/12/31 18 UTC: 16.8 S / 76.7 E, MAX WIND=055 KT, SEVERE TROPICAL STORM
60H: 2012/01/01 06 UTC: 17.7 S / 75.9 E, MAX WIND=060 KT, SEVERE TROPICAL STORM
72H: 2012/01/01 18 UTC: 18.8 S / 75.3 E, MAX WIND=070 KT, TROPICAL CYCLONE

2.B LONGER-RANGE OUTLOOK :
96H: 2012/01/02 18 UTC: 21.0 S / 74.3 E, MAX WIND=070 KT, TROPICAL CYCLONE
120H: 2012/01/03 18 UTC: 22.7 S / 73.6 E, MAX WIND=050 KT, SEVERE TROPICAL STORM

2.C ADDITIONAL INFORMATIONS:
T=CI=2.5+

LAST INFRA RED ANIMATED PICTURES SHOW A GOOD CONSOLIDATION OF THE DEEP CONVECTION NEAR THE LOW LEVEL CENTER. SYSTEM HAS BEEN NAMES BENILDE AT 18Z BY METEOROLOGICAL CENTER OF MAURITIUS.

EASTERLY WINDSHEAR IS RELAXING (CONFIRMED BY CIMSS ANALYSIS AT 15TU).

LOW LEVEL INFLOW IS GOOD POLEWARD ON THE TWO SIDES.
SYSTEM IS EXPECTED TO KEEP ON INTENSIFY SLOWLY ON FRIDAY THEN MORE CLEARLY ON AND AFTER SATURDAY AS IT WILL TRACK UNDER THE UPPER LEVEL RIDGE AND AS TWO UPPER LEVEL OUTLOW CHANNELS WILL BUILD ALOFT ON THE BOTH SIDES IN THE SAME TIME.
IT IS EXPECTED TO REACH ITS MAXIMUM OF INTENSITY ON MONDAY BEFORE UNDERGOING AN UPPER LEVEL CONSTRAINT (WEST-NORTH-WESTERLY WINDSHEAR) AND OVER LESS HEAT OCEANIC CONTENT.

AVALAIBLE NWP MODELS KEEP ON BEEING IN GOOD AGREEMENT FOR A WEST-SOUTHWESTWARDS TRACK OVER THE NORTHERN EDGE OF THE SUBTROPICAL HIGH PRESSURES WITHIN LOW-LEVELS AND MID-LEVELS, THEN MORE SOUTH-WESTWARDS TO SOUTH-SOUTH-WESTWARD TRACK UNDER THE COMBINED EFFECTS OF A FORECAST WEAKENESS IN THE LOW-LEVEL SUBTROPICAL HIGH PRESSURES (IN RELATIONSHIP WITH A TRANSITING POLAR THROUGH), AND OF THE STEERING INFLUENCE OF A BUILDING RIDGE EAST OF THE SYSTEM IN THE MID-LEVELS.
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Re: SWIO: 04R - Tropical Depression (JTWC: TC 04S)

#12 Postby hurricane25 » Thu Dec 29, 2011 2:51 pm

http://www.ssd.noaa.gov/mtsat/flt/t3/avn-l.jpg

Coming together nicely...I'd go with 55 knots, but theres no microwave images that currently cover the core to check the structure.

Seems to be some "low" northeasterly shear, which you can see by the convection "streaming" to the southwestern quad. If that gets to strong, maybe just maybe it might get to the "core" of this, but if not, it could work as a outflow channel=aiding in the development of the cyclone. We will just have to watch.

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#13 Postby HURAKAN » Thu Dec 29, 2011 3:08 pm

Image

Latest infrared
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Re: SWIO: BENILDE - Moderate Tropical Storm

#14 Postby Chickenzilla » Fri Dec 30, 2011 6:06 am

Benilde's convection is weaker than on previous poster's infrared image because of diurnal minimum.
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Infrared and visible images:
Image
Image
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#15 Postby Chacor » Fri Dec 30, 2011 8:14 am

STS:

WTIO30 FMEE 301235
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 10/4/20112012
1.A SEVERE TROPICAL STORM 4 (BENILDE)
2.A POSITION 2011/12/30 AT 1200 UTC:
WITHIN 20 NM RADIUS OF POINT 13.4 S / 78.4 E
(THIRTEEN DECIMAL FOUR DEGREES SOUTH AND SEVENTY EIGHT DECIMAL FOUR DEGREES EAST)
MOVEMENT : WEST-SOUTH-WEST 12 KT
3.A DVORAK ANALYSIS: 3.5/4.0/W 0.5/6 H
4.A CENTRAL PRESSURE: 984 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 55 KT
RADIUS OF MAXIMUM WINDS (RMW) :56 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 130 SE: 560 SW: 280 NW: 130
34 KT NE: 90 SE: 110 SW: 110 NW: 90
48 KT NE: 60 SE: 60 SW: 60 NW: 60
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1008 HPA / 1100 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP
1.B FORECASTS:
12H: 2011/12/31 00 UTC: 14.0 S / 77.3 E, MAX WIND=060 KT, SEVERE TROPICAL STORM
24H: 2011/12/31 12 UTC: 15.3 S / 76.5 E, MAX WIND=070 KT, TROPICAL CYCLONE
36H: 2012/01/01 00 UTC: 16.5 S / 75.6 E, MAX WIND=080 KT, TROPICAL CYCLONE
48H: 2012/01/01 12 UTC: 17.3 S / 75.1 E, MAX WIND=085 KT, TROPICAL CYCLONE
60H: 2012/01/02 00 UTC: 18.4 S / 74.6 E, MAX WIND=085 KT, TROPICAL CYCLONE
72H: 2012/01/02 12 UTC: 19.6 S / 74.0 E, MAX WIND=075 KT, TROPICAL CYCLONE
2.B LONGER-RANGE OUTLOOK :
96H: 2012/01/03 12 UTC: 21.3 S / 73.0 E, MAX WIND=055 KT, SEVERE TROPICAL STORM
120H: 2012/01/04 12 UTC: 22.4 S / 71.1 E, MAX WIND=040 KT, MODERATE TROPICAL STORM
2.C ADDITIONAL INFORMATIONS:
T=3.5 CI=4.0-
BENILDE HAS GLOBALLY WEAKENED FOR THE LAST 6 HOURS. CLOSE TO THE CENTRE, CONVECTION IS FLUCTUATING
AND LESS ORGANIZED.
WITHIN THE NEXT 72 HOURS, AVAILABLE NWP MODELS ARE IN GOOD AGREEMENT TO FORECAST A SOUTH-WESTWARD
TRACK UNDER THE COMBINED EFFECTS OF A FORECAST WEAKNESS IN THE LOW-LEVEL SUBTROPICAL HIGH PRESSURE
S (IN RELATIONSHIP WITH A TRANSITING POLAR THROUGH), AND OF THE STEERING INFLUENCE OF A RIDGE EXIS
TING EAST OF THE SYSTEM IN THE MID-LEVELS. DIVERGENCES EXIST ON THE EXPECTED SPEED OF THE SYSTEM.
ECMWF IS FASTER THAN ARPEGE AND AMERICAN CONSENSUS.
ON THIS TRACK, SYSTEM REMAINS ON THE WESTERN EDGE OF HIGH-LEVEL HIGH PRESSURES LOCATED IN THE EAST
WITH PERSISTENT MODERATE NORTH-EASTERLY VERTICAL WINDSHEAR . DUE TO FASTER SPEED, ECMWF DOES NOT
SEEM CONSIDER THIS WINDSHEAR AND NOTABLY DEEPENS THE SYSTEM UP MONDAY. SO, UNCERTAINTY IS SIGNIFIC
ANT FOR MAXIMUM SYSTEM INTENSITY.
BEYOND TAU 72, SYSTEM IS EXPECTED TO RAPIDLY WEAKEN BY REACHING SEAS WITH MARGINAL HEAT OCEANIC CO
NTENT SOUTH OF 20S AND STRONG WESTERLY WINDSHEAR.
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#16 Postby HURAKAN » Fri Dec 30, 2011 12:52 pm

Image

45 knots? LOL
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#17 Postby CrazyC83 » Fri Dec 30, 2011 1:36 pm

That looks like about 65 kt to me.
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#18 Postby Chacor » Fri Dec 30, 2011 2:14 pm

60 kt now from Réunion...

WTIO30 FMEE 301849
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 11/4/20112012
1.A SEVERE TROPICAL STORM 4 (BENILDE)
2.A POSITION 2011/12/30 AT 1800 UTC:
WITHIN 20 NM RADIUS OF POINT 13.8 S / 77.8 E
(THIRTEEN DECIMAL EIGHT DEGREES SOUTH AND SEVENTY SEVEN DECIMAL EIGHT DEGREES EAST)
MOVEMENT : WEST-SOUTH-WEST 9 KT
3.A DVORAK ANALYSIS: 4.0/4.0/D 1.5/24 H
4.A CENTRAL PRESSURE: 984 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 60 KT RADIUS OF MAXIMUM WINDS (RMW) :61 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM): 28 KT NE: 170 SE: 430 SW: 430 NW: 150
34 KT NE: 90 SE: 260 SW: 260 NW: 90
48 KT NE: 70 SE: 70 SW: 70 NW: 70
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1009 HPA / 1300 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : UNKNOWN

1.B FORECASTS:
12H: 2011/12/31 06 UTC: 14.6 S / 76.4 E, MAX WIND=070 KT, TROPICAL CYCLONE
24H: 2011/12/31 18 UTC: 15.5 S / 75.3 E, MAX WIND=080 KT, TROPICAL CYCLONE
36H: 2012/01/01 06 UTC: 16.8 S / 74.7 E, MAX WIND=085 KT, TROPICAL CYCLONE
48H: 2012/01/01 18 UTC: 17.9 S / 74.2 E, MAX WIND=090 KT, INTENSE TROPICAL CYCLONE
60H: 2012/01/02 06 UTC: 19.1 S / 73.7 E, MAX WIND=085 KT, TROPICAL CYCLONE
72H: 2012/01/02 18 UTC: 20.2 S / 72.9 E, MAX WIND=070 KT, TROPICAL CYCLONE
2.B LONGER-RANGE OUTLOOK :
96H: 2012/01/03 18 UTC: 21.4 S / 71.2 E, MAX WIND=045 KT, MODERATE TROPICAL STORM
120H: 2012/01/04 18 UTC: 21.7 S / 70.2 E, MAX WIND=035 KT, MODERATE TROPICAL STORM

2.C ADDITIONAL INFORMATIONS:
T=4.0+ AND CI=4.0+

BENILDE INTENSIFIES AGAIN AND SHOWS TEMPORARILY AN EYE ON METEOSAT 7
INFRARED IMAGERY FROM 1500Z TO 1630Z.

INSTANTANEOUS DVORAK ANALYSIS HAS CONSEQUENTLY FLUCTUATED WITHIN
THE LAST 06 HOURS AND MENTIONED INTENSITY FOR THIS FIX IS AN AVERAGE
OVER THIS PERIOD.

WINDS EXTENSION HAS BEEN RECALIBRATED THANKS TO 1645Z ASCAT SWATH.

DETERMINISTIC NWP MODELS ARE GLOBALLY IN GOOD AGREEMENT TO FORECAST
A SOUTHWESTWARDS TRACK WITHIN THE NEXT 72 HOURS UNDER THE COMBINED
STEERING INFLUENCES OF OF A MID-LEVELS RIDGE EXISTING EAST OF THE
SYSTEM AND A POLAR TROUGH TRANSITING IN THE SOUTH.
MULTI-ENSEMBLE NWP MODELS (EPS, GEFS AND PEARP) PLUMES SHOW LOW
DISPERSION AND CONVERGE ALSO TO THIS SCENARIO.

THERE IS SOME DISCREPENCIES ABOUT CHRONOLOGY BETWEEN DETERMINISTIC
NWP MODELS. ECMWF ONE IS FASTER THAN ARPEGE, GFS AND THE AMERICAN
CONSENSUS ONES.

BEYOND TAU 72, SYSTEM IS EXPECTED TO RAPIDLY WEAKEN OVER MARGINAL
HEAT OCEANIC CONTENT SOUTH OF 20S AND STRENGTHENING WESTERLY
WINDSHEAR.

MULTI-ENSEMBLE SUGGESTS THEN MORE DISPERSION BETWEEN THE MEMBERS.
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Re: SWIO: BENILDE - Severe Tropical Storm

#19 Postby HURAKAN » Fri Dec 30, 2011 3:17 pm

Code: Select all

201112301800   -13.7   77.9   65
201112301200   -13.5   78.7   45
201112300600   -13.3   79.5   50


JTWC goes from 50 to 45 kt and now 65 kt, lol
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#20 Postby HURAKAN » Fri Dec 30, 2011 6:41 pm

Image

Rapidly intensifying
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