SIO : MODERATE TROPICAL STORM DAVID (05S)

[Crostorm]

ZCZC 532
WTIO30 FMEE 201820
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 6/7/20092010
1.A TROPICAL DISTURBANCE 7
2.A POSITION 2009/12/20 AT 1800 UTC :
WITHIN 30 NM RADIUS OF POINT 10.7S / 61.9E
(TEN DECIMAL SEVEN DEGREES SOUTH AND SIXTY ONE DECIMAL NINE DEGREES
EAST)
MOVEMENT : QUASI-STATIONARY
3.A DVORAK ANALYSIS : 2.0/2.0 /D 0.5/24 H
4.A CENTRAL PRESSURE : 1000 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 25 KT
RADIUS OF MAXIMUM WINDS (RMW) : 25 KM
6.A EXTENSION OF WINDS BY QUADRANTS (KM):
NIL
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 1000
KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM
1.B FORECASTS:
12H: 2009/12/21 06 UTC: 10.8S/62.0E, MAX WIND=030KT, TROP.
DEPRESSION.
24H: 2009/12/21 18 UTC: 11.1S/62.2E, MAX WIND=035KT, MODERATE TROP.
STORM
.
36H: 2009/12/22 06 UTC: 11.5S/62.8E, MAX WIND=040KT, MODERATE TROP.
STORM
.
48H: 2009/12/22 18 UTC: 12.2S/63.5E, MAX WIND=045KT, MODERATE TROP.
STORM
.
60H: 2009/12/23 06 UTC: 13.2S/64.2E, MAX WIND=045KT, MODERATE TROP.
STORM
.
72H: 2009/12/23 18 UTC: 14.1S/65.7E, MAX WIND=045KT, MODERATE TROP.
STORM
.
2.B OTHER INFORMATIONS:
T=CI=2.0+
THE SYSTEM NR7 KEEPS ON UNDERGOING A NORTHWESTERLY CONSTRAINT, SHOWN
ON
THE IMAGERY WITH THE LLCC EXPOSED NORTHWEST OF THE DEEP CONVECTION
(SEE
F17 20/1333Z AND WINDSAT 20/1414Z).
IN RELATIONSHIP WITH THIS VERTICAL WINDSHEAR , THE SYSTEM DOESN'T
SEEM
DEEPENING SIGNIFICANTLY WITHIN THE RECENT PAST 12 HOURS.
IT HAS TODAY CLEARLY SLOW DOWN AND STAYS NOW QUASI-STATIONNARY.
SYSTEM ENVIRONNEMENT IS NEUTRAL; LOW LEVEL INFLOWS ARE ESTABLISHED,
UPPER
LEVEL DIVERGENCE AS WELL - MAINLY POLEWARDS- BUT A WEAK TO MODERATE
WINDSHEAR STILL EXISTS. THE SYSTEM SHOULD HOWEVER INTENSIFY SLOWLY
WITHIN
THE NEXT DAYS, AS THE MONSOON INFLOW STRENGTHENS.
NWP DISAGREE WITH THE SPEED OF THE MOTION BUT ARE IN GOOD AGREEMENT
WITH
A SWINGING TRACK. THE SYSTEM IS INDEED UNDER THE STEERING OF TWO
COMPETING FLOWS ASSOCIATED TO THE SUBTROPICAL RIDGE, AND A RIDGE
LOCATED
NEAR THE EQUATOR.
THE TRACK FORECAST IS BASED ON A CONSENSUS OF THE AVAILABLE NWP.=
NNNN

[Crostorm]

[HURAKAN]

ZCZC 148
WTIO30 FMEE 210026
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 7/7/20092010
1.A TROPICAL DISTURBANCE 7
2.A POSITION 2009/12/21 AT 0000 UTC :
WITHIN 30 NM RADIUS OF POINT 10.6S / 61.8E
(TEN DECIMAL SIX DEGREES SOUTH AND SIXTY ONE DECIMAL EIGHT DEGREES
EAST)
MOVEMENT : QUASI-STATIONARY
3.A DVORAK ANALYSIS : 2.0/2.0 /S 0.0/24 H
4.A CENTRAL PRESSURE : 1000 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 25 KT
RADIUS OF MAXIMUM WINDS (RMW) : 25 KM
6.A EXTENSION OF WINDS BY QUADRANTS (KM):
NIL
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 1000
KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM
1.B FORECASTS:
12H: 2009/12/21 12 UTC: 10.6S/62.1E, MAX WIND=030KT, TROP.
DEPRESSION.
24H: 2009/12/22 00 UTC: 11.1S/62.7E, MAX WIND=030KT, TROP.
DEPRESSION.
36H: 2009/12/22 12 UTC: 11.9S/63.7E, MAX WIND=030KT, TROP.
DEPRESSION.
48H: 2009/12/23 00 UTC: 12.9S/64.7E, MAX WIND=030KT, TROP.
DEPRESSION.
60H: 2009/12/23 12 UTC: 13.8S/65.9E, MAX WIND=035KT, MODERATE TROP.
STORM
.
72H: 2009/12/24 00 UTC: 14.6S/66.7E, MAX WIND=035KT, MODERATE TROP.
STORM
.
2.B OTHER INFORMATIONS:
T=CI=2.0+
THE SYSTEM NR7 KEEPS ON UNDERGOING A WEST-NORTHWESTERLY CONSTRAINT,
SHOWN
ON THE IMAGERY WITH THE LLCC EXPOSED WEST OF THE DEEP CONVECTION
(SEE
AQUA 20/2106Z AND NOAA18 20/2132Z).
IN RELATIONSHIP WITH THIS VERTICAL WINDSHEAR , THE SYSTEM DOESN'T
SEEM
DEEPENING SIGNIFICANTLY WITHIN THE RECENT PAST 12 HOURS.
IT HAS CLEARLY SLOW DOWN AND STAYS NOW QUASI-STATIONNARY.
20/1659Z ASCAT SWATH SHOWS 35KT MAXIMUM WINDS UNDER THE DEEP
CONVECTION
EAST OF THE LLCC BUT THESE WINDS ARE PROBABLY CONTAMINATED BY HEAVY
RAIN.
THE PRESENT WESTERLY WINDSHEAR IS EXPECTED TO BE NORTH-NORTHWESTERLY
ON
AND AFTER WEDNESDAY (SEE ECMWF AND ALADIN-REUNION NWP MODEL), IT
WOULD
NOT ALLOW SYSTEM TO INTENSIFY SIGNIFICANTLY WITHIN THE NEXT 72 HOURS
DESPITE THE MONSOON INFLOW STRENGTHENS.
NWP DISAGREE WITH THE SPEED OF THE MOTION BUT ARE GLOBALLY IN GOOD
AGREEMENT WITH A SWINGING TRACK TOWARDS THE SOUTHEAST IN A FIRST
TIME.
THE SYSTEM IS INDEED UNDER THE STEERING OF TWO COMPETING FLOWS
ASSOCIATED
TO THE SUBTROPICAL RIDGE, AND A RIDGE LOCATED NEAR THE EQUATOR.
THE TRACK FORECAST IS BASED ON A CONSENSUS OF THE AVAILABLE NWP.=
NNNN

[Crostorm]

TXXS26 KNES 210318


A. 05S (NONAME)

B. 21/0300Z

C. 10.6S

D. 62.2E

E. FIVE/MET-7

F. T2.0/2.5/W0.5/24HRS

G. IR/EIR/VIS/AMSRE/SSMI

H. REMARKS...DT OF 1.5 BASED ON .2-.3 BANDING. MET IS 2.5 WITH PT
OF 2.0. FT BASED ON PT.

I. ADDL POSITIONS

20/2106Z 10.5S 61.8E AMSRE
21/0107Z 10.3S 61.9E SSMI


...LIDDICK

[Crostorm]

[P.K.]

07R has been upgraded from a TD to Moderate Tropical Storm David.

WTIO30 FMEE 211225

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

0.A WARNING NUMBER : 9/7/20092010
1.A MODERATE TROPICAL STORM 7 (DAVID)

2.A POSITION 2009/12/21 AT 1200 UTC :
WITHIN 20 NM RADIUS OF POINT 10.8S / 62.9E
(TEN DECIMAL EIGHT DEGREES SOUTH AND SIXTY TWO DECIMAL NINE DEGREES
EAST)
MOVEMENT : EAST-SOUTH-EAST 8 KT

3.A DVORAK ANALYSIS : 2.5/2.5 /D 0.5/24 H
4.A CENTRAL PRESSURE : 995 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 35 KT
RADIUS OF MAXIMUM WINDS (RMW) : 30 KM

6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 200 SE: 200 SO: 110 NO: 055

7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 700 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP

1.B FORECASTS:
12H: 2009/12/22 00 UTC: 11.0S/63.4E, MAX WIND=035KT , MODERATE TROP.
STORM.
24H: 2009/12/22 12 UTC: 11.6S/64.5E, MAX WIND=040KT , MODERATE TROP.
STORM.
36H: 2009/12/23 00 UTC: 12.2S/65.6E, MAX WIND=040KT , MODERATE TROP.
STORM.
48H: 2009/12/23 12 UTC: 12.9S/66.6E, MAX WIND=040KT , MODERATE TROP.
STORM.
60H: 2009/12/24 00 UTC: 13.9S/67.9E, MAX WIND=045KT , MODERATE TROP.
STORM.
72H: 2009/12/24 12 UTC: 14.5S/68.5E, MAX WIND=050KT , SEVERE TROP.
STORM.

2.B OTHER INFORMATIONS:
T=CI=2.5+

SATELLITE DATA SHOW THAT THE SYSTEM HAS MAINTAIN ITS SLOW
INTENSIFICATION
TREND TODAY DESPITE THE MODERATE WESTNORTHWESTERLY SHEAR. WV IMAGERY
SUGGEST SLIGHT IMPROVMENT OF THE OUTFLOW OVER THE WESTERN
SEMI-CIRCLE.
ASCAT OF 06Z AGREE WITH CURRENT ANALYSIS. CONSEQUENTLY SYSTEM HAS
BEEN
UPGRADED TO A M
INIMAL MODERATE TROPICAL STORM (CI:2.5+ AND MAX WINDS AT 35 KT) AN
DHAS
BEEN NAMED 'DAVID' BY THE MAURITIUS METEOROLOGICAL SERVICE. LATEST
SATELLITE FIX SEEM INDICATE A LITTLE BIT MORE SPEEDY EASTWARDS
MOVEMENT.

THE CURRENT SHEAR IS EXPECTED TO TURN NORTH-NORTHWESTERLY WEDNESDAY
BEFORE LESSEN A LITTLE BIT ON THURSDAY. IT SHOULD MAINTAIN OVER THE
NEXT
THREE DAYS AND BE THE UNFAVORABLE FACTOR FOR INTENSIFICATION THAT IS
STILL FORECASTED TO BE RATHER LIMITED.

NWP DISAGREE WITH THE SPEED OF THE MOTION BUT SUGGEST THAT THE
STEERING
FLOW SHOULD BE DRIVE BY THE LOW TO MID-LEVEL EQUATORWARDS RIDGE
LOCATED
TO THE NORTHEAST FOR THE NEXT THREE DAYS. AT TAU 72H, SYSTEM SHOULD
SLOW
DOWN DUE TO A STRENGHENING STR.

THERE IS SOME CONSIDERABLE DISPERSION AMONG NWP MODEL ABOUT HOW LONG
AND
HOW FAR THE SOUTHEASTERN MOTION WILL TAKE, THE PRESENT TRACK FORECAST
IS
BASED ON A CONSENSUS OF THE AVAILABLE NWP.=

[HURAKAN]

Latest

[HURAKAN]

WTXS32 PGTW 210900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 05S (FIVE) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 05S (FIVE) WARNING NR 006
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
210600Z --- NEAR 10.7S 62.1E
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 01 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: 10.7S 62.1E
---
FORECASTS:
12 HRS, VALID AT:
211800Z --- 11.0S 62.4E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 130 DEG/ 03 KTS
---
24 HRS, VALID AT:
220600Z --- 11.4S 62.9E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 120 DEG/ 06 KTS
---
36 HRS, VALID AT:
221800Z --- 12.0S 63.9E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 130 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
230600Z --- 12.7S 64.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 135 DEG/ 05 KTS
---
72 HRS, VALID AT:
240600Z --- 14.2S 66.3E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 150 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
250600Z --- 15.4S 67.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 175 DEG/ 02 KTS
---
120 HRS, VALID AT:
260600Z --- 16.3S 67.1E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
210900Z POSITION NEAR 10.8S 62.2E.
TROPICAL CYCLONE (TC) 05S (FIVE), LOCATED APPROXIMATELY 645 NM WEST-
SOUTHWEST OF DIEGO GARCIA, HAS REMAINED QUASISTATIONARY OVER THE
PAST SIX HOURS. FIVE REMAINS A MINIMAL CYCLONE AND HAS BEEN UNABLE
TO INTENSIFY TO MORE THAN 35 KNOT KNOTS DUE TO MODERATE WESTERLY
SHEAR. DESPITE SATELLITE INTENSITY ESTIMATES FROM PGTW AND FMEE ONLY
INDICATING A 30 KNOT SYSTEM, THE INITIAL FORECAST INTENSITY HAS BEEN
SET SLIGHTLY HIGHER TO ACCOUNT FOR THE FLARING NATURE OF THE DEEP
CONVECTION. MORE RECENTLY CONVECTION HAS BEGUN TO DEEPEN NEAR THE
CENTER, BUT IS SIGNIFICANTLY LIMITED WITHIN THE WESTERN QUADRANTS OF
THE CIRCULATION. THE LOW LEVEL CIRCULATION CENTER (LLCC)IS PARTIALLY
EXPOSED ON THE WESTERN EDGE OF THE CORE CONVECTION, WHICH IS
CONFIRMED BY AN EARLIER 202106Z AMSRE IMAGE. THE LLCC HAS MOVED
LITTLE SINCE THIS TIME. THE SYSTEM IS WEDGED BETWEEN A NEAR
EQUATORIAL STEERING RIDGE TO THE NORTHEAST AND AN EXTENSION OF THE
SUBTROPICAL RIDGE TO THE SOUTHWEST IN A WEAK STEERING ENVIRONMENT.
EVENTUALLY THE NEAR EQUATORIAL RIDGE WILL STRENGTHEN TO THE NORTH
WHILE PUSHING POLEWARD AND WILL BECOME THE PREDOMINANT STEERING
MECHANISM. THE SYSTEM WILL SLOWLY TRACK TO THE SOUTHEAST ALONG THE
SOUTHWESTERN PERIPHERY OF THIS RIDGE WHILE ACCELERATING TOWARDS A
TROUGH-INDUCED WEAKNESS IN THE MID-LEVEL SUBTROPICAL RIDGE. ONCE THE
TROUGH IS SUFFICIENTLY DOWNSTREAM, NEAR TAU 96, THE RIDGE WILL
REBUILD TO THE SOUTH, RETARDING POLEWARD MOTION AND BENDING THE
FORECAST TRACK EVER SO SLIGHTLY BACK TO THE WEST. THE SYSTEM IS NOW
EXPECTED TO PEAK NEAR 50 KNOTS AROUND TAU 72 (10 KNOTS LESS THAN THE
PREVIOUS FORECAST). MODERATE VERTICAL WIND SHEAR WILL HINDER
AGGRESSIVE INTENSIFICATION. THERE IS SIGNIFICANT SPREAD IN THE
AVAILABLE DYNAMICAL MODEL TRACKERS, BUT IN GENERAL THEY BRING THE
SYSTEM BACK TO THE (SOUTH)EAST. GIVEN THE CURRENTLY WEAK STEERING
ENVIRONMENT, THE FORECAST TRACK IS SLOWER THAN CONSENSUS.
DISSIPATION IS EXPECTED TO BEGIN NEAR DAY 5 AS VERTICAL WIND SHEAR
FURTHER ELEVATES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210600Z IS 9
FEET. NEXT WARNINGS AT 212100Z AND 220900Z. REFER TO TROPICAL
CYCLONE 06S (LAURENCE) WARNINGS (WTXS33 PGTW) FOR TWELVE-HOURLY
UPDATES.//
NNNN

[HURAKAN]

Latest

[HURAKAN]

ZCZC 955
WTIO30 FMEE 211816 CCA
*************** CORRECTIVE **************
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 10/7/20092010
1.A MODERATE TROPICAL STORM 7 (DAVID)
2.A POSITION 2009/12/21 AT 1800 UTC :
WITHIN 20 NM RADIUS OF POINT 11.1S / 63.6E
(ELEVEN DECIMAL ONE DEGREES SOUTH AND SIXTY THREE DECIMAL SIX DEGREES
EAST)
MOVEMENT : EAST-SOUTH-EAST 8 KT
3.A DVORAK ANALYSIS : 2.5/2.5 /D 0.5/24 H
4.A CENTRAL PRESSURE : 995 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 35 KT
RADIUS OF MAXIMUM WINDS (RMW) : 30 KM
6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 200 SE: 200 SO: 110 NO: 055
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 900 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP
1.B FORECASTS:
12H: 2009/12/22 06 UTC: 11.7S/64.8E, MAX WIND=035KT , MODERATE TROP.
STORM.
24H: 2009/12/22 18 UTC: 12.3S/66.1E, MAX WIND=040KT , MODERATE TROP.
STORM.
36H: 2009/12/23 06 UTC: 13.0S/67.5E, MAX WIND=040KT , MODERATE TROP.
STORM.
48H: 2009/12/23 18 UTC: 13.8S/68.7E, MAX WIND=040KT , MODERATE TROP.
STORM.
60H: 2009/12/24 06 UTC: 14.6S/69.3E, MAX WIND=045KT , MODERATE TROP.
STORM.
72H: 2009/12/24 18 UTC: 15.3S/69.7E, MAX WIND=050KT , SEVERE TROP.
STORM.
2.B OTHER INFORMATIONS:
T=CI=2.5+
THE POSTION IS EXTRAPOLATED FROM THE TRMM/1504Z FIX, WHICH SEEMS TO
CONFIRM THE ACCELERATION TOWARDS THE EAST-SOUTHEAST.
CURRENTLY, ON THE ANIMATED IMAGERY AND MW IMAGERY, THE SYSTEM KEEPS A
RATHER SIMILAR STRUCTURE THAN DURING THE LAST HOURS.
LOW LEVEL INFLOWS ARE ESTABLISHED, POLEWARD UPPER LEVEL DIVERGENCE AS
WELL, BUT THE SYSTEM STILL UNDERGOES A WESTERLY WINDSHEAR. THIS
CURRENT
WINDSHEAR IS EXPECTED TO VEER NORTH-NORTHWESTERLY ON WEDNESDAY BEFORE
SLIGHTLY LESSEN ON THURSDAY. IT SHOULD MAINTAIN OVER THE NEXT COMING
DAYS
AND BE THE UNF
AVORABLE FACTOR FOR INTENSIFICATION WHICH IS THEREFORE FORECASTED TO
BE
RATHER LIMITED.
NWP DISAGREE WITH THE SPEED OF THE MOTION BUT SUGGEST THE STEERING
FLOW
SHOULD BE DRIVEN BY THE LOW TO MID-LEVEL EQUATORWARDS RIDGE LOCATED
TO
THE NORTHEAST FOR THE NEXT TWO TO THREE DAYS. AT RANGE 60 TO 72H,
SYSTEM
SHOULD SLOW DOWN DUE TO A STRENGTHENING SUBTROPICAL RIDGE.
THERE IS SOME CONSIDERABLE DISPERSION AMONG NWP MODEL ABOUT THE
DURATION
OF THIS SOUTHEASTERN MOTION.
THE PRESENT TRACK FORECAST IS BASED ON A CONSENSUS OF THE AVAILABLE
NWP.=
NNNN

[HURAKAN]

21/1430 UTC 11.3S 63.5E T3.0/3.0 DAVID -- Southwest Indian

45 knots

[HURAKAN]

WTXS32 PGTW 212100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 05S (DAVID) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 05S (DAVID) WARNING NR 007
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
211800Z --- NEAR 11.2S 63.5E
MOVEMENT PAST SIX HOURS - 100 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
REPEAT POSIT: 11.2S 63.5E
---
FORECASTS:
12 HRS, VALID AT:
220600Z --- 11.5S 64.7E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 105 DEG/ 06 KTS
---
24 HRS, VALID AT:
221800Z --- 11.8S 65.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 115 DEG/ 07 KTS
---
36 HRS, VALID AT:
230600Z --- 12.4S 67.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 125 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
231800Z --- 13.2S 68.3E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 140 DEG/ 06 KTS
---
72 HRS, VALID AT:
241800Z --- 15.1S 70.0E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 185 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
251800Z --- 16.5S 69.9E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 220 DEG/ 06 KTS
---
120 HRS, VALID AT:
261800Z --- 18.4S 68.2E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
212100Z POSITION NEAR 11.3S 63.8E.
TROPICAL CYCLONE (TC) 05S (DAVID), LOCATED APPROXIMATELY 580 NM WEST-
SOUTHWEST OF DIEGO GARCIA, HAS TRACKED EASTWARD AT 06 KNOTS OVER THE
PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY INDICATES SLIGHT
IMPROVEMENT IN ORGANIZATION OVER THE PAST 12 HOURS DESPITE MODERATE
NORTHWESTERLY VERTICAL WIND SHEAR (VWS). A 211504Z TRMM 37V IMAGE
DEPICTS CONVECTIVE BANDING WRAPPING FROM THE NORTH INTO THE SOUTH
QUADRANT. THERE IS FAIR CONFIDENCE IN THE CURRENT POSITION BASED ON
THE IMPROVED MICROWAVE SIGNATURE HOWEVER, THE LOW LEVEL CIRCULATION
CENTER APPEARS TO BE PARTIALLY EXPOSED ALONG THE NORTHWESTERN TIP OF
THE DEEP CONVECTION. ANIMATED WATER VAPOR IMAGERY DEPICTS WESTERLY
DIFFLUENT FLOW OVER THE SYSTEM, PRODUCING FAIR POLEWARD OUTFLOW. THE
POLEWARD OUTFLOW IS ALSO BEING ENHANCED BY AN UPPER LEVEL LOW
LOCATED JUST WEST OF AUSTRALIA. THE CURRENT INTENSITY IS BASED ON AN
AVERAGE OF DVORAK ESTIMATES OF 35-45 KNOTS. TC 05S IS CURRENTLY
BEING STEERED BY A LOW TO MID-LEVEL NEAR EQUATORIAL RIDGE (NER)
POSITIONED TO THE NORTHEAST. THE SYSTEM IS FORECAST TO CONTINUE
TRACKING EAST-SOUTHEASTWARD TO SOUTHEASTWARD THROUGH TAU 72. IN THE
EXTENDED TAUS, TC DAVID IS EXPECTED TO SLOW AND TURN SOUTHWESTWARD
UNDER THE STEERING INFLUENCE OF A DEVELOPING SUBTROPICAL RIDGE
POSITIONED SOUTH OF THE SYSTEM. THE AVAILABLE NUMERICAL GUIDANCE
INCLUDING NGPS, GFDN, UKMO, ECMWF, WBAR, AND GFS SUPPORT THE SHARP
SOUTHWESTWARD TURN AND DEVELOPMENT OF THE SUBTROPICAL RIDGE. THERE
ARE SIGNIFICANT DIFFERENCES IN THE TIMING OF THE TURN AS WELL AS THE
ORIENTATION OF THE NER. THIS FORECAST FAVORS THE UKMO, ECMWF, AND
GFDN SOLUTIONS, WHICH INDICATE A CONTINUED EASTWARD TRACK THROUGH
TAU 48 FOLLOWED BY THE TURN SOUTHWESTWARD. THE SYSTEM IS EXPECTED TO
INTENSIFY SLIGHTLY DUE TO FAIR POLEWARD OUTFLOW OFFSET BY MODERATE
VWS AND MARGINAL OCEAN HEAT CONTENT. AFTER TAU 72, TC 05S SHOULD
WEAKEN DUE TO COOLER SST AS WELL AS MODERATE VWS. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 211800Z IS 10 FEET. NEXT WARNINGS AT
220900Z AND 222100Z. REFER TO TROPICAL CYCLONE 06S (LAURENCE) FINAL
WARNING (WTXS33 PGTW).//
NNNN

[HURAKAN]

Latest. Looking a lot better

[HURAKAN]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 22 DEC 2009 Time : 023000 UTC
Lat : 11:25:54 S Lon : 64:21:22 E


CI# /Pressure/ Vmax
3.3 / 986.8mb/ 51.0kt


Final T# Adj T# Raw T#
3.3 3.4 4.1

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -77.4C Cloud Region Temp : -78.5C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

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

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

ZCZC 621
WTIO30 FMEE 220023
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 11/7/20092010
1.A MODERATE TROPICAL STORM 7 (DAVID)
2.A POSITION 2009/12/22 AT 0000 UTC :
WITHIN 30 NM RADIUS OF POINT 11.3S / 64.0E
(ELEVEN DECIMAL THREE DEGREES SOUTH AND SIXTY FOUR DECIMAL ZERO
DEGREES
EAST)
MOVEMENT : EAST-SOUTH-EAST 6 KT
3.A DVORAK ANALYSIS : 3.0/3.0 /D 1.0/24 H
4.A CENTRAL PRESSURE : 990 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 40 KT
RADIUS OF MAXIMUM WINDS (RMW) : 30 KM
6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 200 SE: 220 SO: 120 NO: 060
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1009 HPA / 1000
KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP
1.B FORECASTS:
12H: 2009/12/22 12 UTC: 12.0S/65.0E, MAX WIND=040KT, MODERATE TROP.
STORM
.
24H: 2009/12/23 00 UTC: 12.6S/66.0E, MAX WIND=040KT, MODERATE TROP.
STORM
.
36H: 2009/12/23 12 UTC: 13.5S/67.3E, MAX WIND=045KT, MODERATE TROP.
STORM
.
48H: 2009/12/24 00 UTC: 14.2S/68.0E, MAX WIND=050KT, SEVERE TROP.
STORM.
60H: 2009/12/24 12 UTC: 14.7S/68.4E, MAX WIND=050KT, SEVERE TROP.
STORM.
72H: 2009/12/25 00 UTC: 15.0S/68.5E, MAX WIND=050KT, SEVERE TROP.
STORM.
2.B OTHER INFORMATIONS:
T=CI=3.0
THE POSTION IS EXTRAPOLATED FROM THE AMSU/2121Z FIX.
SYSTEM'S ASPECT HAS IMPROVED ON THE ANIMATED IMAGERY, WITH A
WESTERLY
WINDSHEAR WHICH SEEMS TO SLIGHTLY LESSEN (BETTER EXPANSION TOWARDS
THE
WEST ON THE ANIMATED VAPOUR WATER IMAGERY).
LOW LEVEL INFLOWS ARE ESTABLISHED, POLEWARD UPPER LEVEL DIVERGENCE AS
WELL, BUT THE SYSTEM STILL UNDERGOES A WESTERLY WINDSHEAR -EVEN
SLIGHTLY
WEAKENED. THIS CURRENT WINDSHEAR IS EXPECTED TO VEER
NORTH-NORTHWESTERLY
ON WEDNESDAY BEFORE SLIGHTLY LESSEN ON THURSDAY. IT SHOULD MAINTAIN
OVER
THE NEXT CO
MING DAYS AND BE THE UNFAVORABLE FACTOR FOR INTENSIFICATION, WHICH IS
THEREFORE FORECASTED TO BE RATHER LIMITED.
NWP DISAGREE WITH THE SPEED OF THE MOTION BUT SUGGEST THE STEERING
FLOW
SHOULD BE DRIVEN BY THE LOW TO MID-LEVEL EQUATORWARDS RIDGE LOCATED
TO
THE NORTHEAST FOR THE NEXT TWO DAYS. AT RANGE 60 TO 72H, DUE TO A
STRENGTHENING SUBTROPICAL RIDGE, THE SYSTEM SHOULD BE WEDGED BETWEEN
TWO
COMPETING STEERING
FLOWS, AND ITS MOTION SHOULD SLOW DOWN.
THERE IS SOME CONSIDERABLE DISPERSION AMONG NWP MODEL ABOUT THE
DURATION
OF THIS SOUTHEASTERN MOTION.
THE PRESENT TRACK FORECAST IS BASED ON A CONSENSUS OF THE AVAILABLE
NWP.=
NNNN

[HURAKAN]

Looks like an eye is developing

[HURAKAN]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 22 DEC 2009 Time : 050000 UTC
Lat : 11:28:50 S Lon : 64:36:10 E


CI# /Pressure/ Vmax
3.5 / 985.0mb/ 55.0kt


Final T# Adj T# Raw T#
3.5 3.8 4.1

Latitude bias adjustment to MSLP : +1.0mb

Center Temp : -79.2C Cloud Region Temp : -77.9C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

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

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

Latest

[HURAKAN]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 22 DEC 2009 Time : 063000 UTC
Lat : 11:30:34 S Lon : 64:44:53 E


CI# /Pressure/ Vmax
3.8 / 981.1mb/ 61.0kt


Final T# Adj T# Raw T#
3.8 4.0 4.1

Latitude bias adjustment to MSLP : +1.9mb

Center Temp : -79.2C Cloud Region Temp : -78.8C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

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

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

ZCZC 663
WTIO30 FMEE 220629
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 12/7/20092010
1.A MODERATE TROPICAL STORM 7 (DAVID)
2.A POSITION 2009/12/22 AT 0600 UTC :
WITHIN 20 NM RADIUS OF POINT 11.5S / 64.6E
(ELEVEN DECIMAL FIVE DEGREES SOUTH AND SIXTY FOUR DECIMAL SIX DEGREES
EAST)
MOVEMENT : EAST-SOUTH-EAST 6 KT
3.A DVORAK ANALYSIS : 3.0/3.0 /D 0.5/18 H
4.A CENTRAL PRESSURE : 988 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 45 KT
RADIUS OF MAXIMUM WINDS (RMW) : 45 KM
6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 240 SE: 220 SO: 120 NO: 070
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 900 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP
1.B FORECASTS:
12H: 2009/12/22 18 UTC: 12.4S/65.9E, MAX WIND=045KT, MODERATE TROP. STORM
.
24H: 2009/12/23 06 UTC: 13.1S/66.7E, MAX WIND=045KT, MODERATE TROP. STORM
.
36H: 2009/12/23 18 UTC: 13.7S/67.2E, MAX WIND=050KT, SEVERE TROP. STORM.
48H: 2009/12/24 06 UTC: 14.1S/67.5E, MAX WIND=055KT, SEVERE TROP. STORM.
60H: 2009/12/24 18 UTC: 14.4S/67.7E, MAX WIND=055KT, SEVERE TROP. STORM.
72H: 2009/12/25 06 UTC: 14.8S/67.8E, MAX WIND=050KT, SEVERE TROP. STORM.
2.B OTHER INFORMATIONS:
T=CI=3.0+
SSMIS-F16 AT 03.08Z SUGGESTS THAT A LIGHT UPPER LEVELS WINDSHEAR PERSISTS
OVER THE SYSTEM (THE LLCC IS OFFSET NORTH-NORTHWESTWARD).
LOW LEVEL CONVERGENCE IS ESTABLISHED, POLEWARD UPPER LEVEL DIVERGENCE AS
WELL.
WINDSHEAR IS EXPECTED TO VEER NORTH-NORTHWESTERLY ON WEDNESDAY BEFORE
SLIGHTLY LESSEN ON THURSDAY, AND STRENGTHEN AGAIN AT THE END OF THE
FORECAST PERIOD. IT SHOULD BE THE UNFAVORABLE FACTOR FOR INTENSIFICATION
, WHICH IS THEREFORE FORECASTED TO BE RATHER LIMITED.
NWP DISAGREE WITH THE SPEED OF THE MOTION BUT SUGGEST THE STEERING FLOW
IS DRIVEN BY THE MID-LEVEL EQUATORWARDS RIDGE LOCATED TO THE NORTHEAST
FOR THE NEXT TWO DAYS. AFTER RANGE 48H, DUE TO A STRENGTHENING
SUBTROPICAL RIDGE, THE SYSTEM SHOULD BE WEDGED BETWEEN TWO COMPETING
STEERING FLOWS, AND ITS M
OTION SHOULD SLOW DOWN.
THERE IS SOME CONSIDERABLE DISPERSION AMONG NWP MODEL ABOUT THE DURATION
OF THIS SOUTHEASTERN MOTION.
THE PRESENT TRACK FORECAST IS BASED ON A CONSENSUS OF THE AVAILABLE NWP.
NNNN