
ZCZC 272
WTIO30 FMEE 101226
RSMC / TROPICAL CYCLONE CENTRE / LA REUNION
TROPICAL CYCLONE TECHNICAL BULLETIN (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER : 25/8/20092010
1.A TROPICAL CYCLONE 8 (EDZANI)
2.A POSITION 2010/01/10 AT 1200 UTC :
WITHIN 20 NM RADIUS OF POINT 22.1S / 71.4E
(TWENTY TWO DECIMAL ONE DEGREES SOUTH AND SEVENTY ONE DECIMAL FOUR
DEGREES EAST)
MOVEMENT : SOUTH 9 KT
3.A DVORAK ANALYSIS : 4.5/5.0 /W 1.0/24 H
4.A CENTRAL PRESSURE : 960 HPA
5.A MAX AVERAGE WIND SPEED (10 MN) : 75 KT
RADIUS OF MAXIMUM WINDS (RMW) : 13 KM
6.A EXTENSION OF WINDS BY QUADRANTS (KM):
30 KT NE: 340 SE: 360 SO: 190 NO: 270
50 KT NE: 055 SE: 055 SO: 040 NO: 040
7.A FIRST CLOSED ISOBARE (PRESSURE / AVERAGE DIAM): 1008 HPA / 1200
KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: DEEP
1.B FORECASTS:
12H: 2010/01/11 00 UTC: 23.7S/71.4E, MAX WIND=060KT, SEVERE TROP.
STORM.
24H: 2010/01/11 12 UTC: 25.0S/71.8E, MAX WIND=050KT, SEVERE TROP.
STORM.
36H: 2010/01/12 00 UTC: 25.4S/71.2E, MAX WIND=045KT, MODERATE TROP.
STORM
.
48H: 2010/01/12 12 UTC: 26.2S/69.6E, MAX WIND=040KT, MODERATE TROP.
STORM
.
60H: 2010/01/13 00 UTC: 26.7S/67.7E, MAX WIND=040KT, MODERATE TROP.
STORM
.
72H: 2010/01/13 12 UTC: 28.7S/67.1E, MAX WIND=035KT, MODERATE TROP.
STORM
.
2.B OTHER INFORMATIONS:
T=4.5- AND CI=5.0-
SLOW WEAKENING IS STILL ON THE WAY. EDZANI HAS LOST ITS EYE PATTERN
ON
ENHANCED-IR IMAGERY SINCE 09Z. MEAN DT OVER THE LAST 6 HRS IS AT 4.5.
LATEST AVAILABLE MW IMAGERY (N19 PASS AT 0851Z) SUGGESTS THAT THE
SYSTEM
STILL UNDERGO AN EROSION OF THE WESTERN PART OF THE EYEWALL.
TC HAS TRACK MORE SOUTHWARDS WITH A SLOW DOWN IN SPEED.
EDZANI IS NOW OVER COOLER WATERS AND LATEST AVAILABLE NWP OUTPUTS
FROM
ECMWF SHOW AN INCREASING WESTERLY SHEAR TOMORROW MORNING.
CONSEQUENTLY
WEAKENING TREND HAS BEEN UPGRADED FOR TOMORROW.
IT IS EXPECTED TO SLOW DOWN WITHIN THE NEXT 36 HOURS AS STR REBUILD
SOUTHWARDS. TRACK SHOULD CONSEQUENTLY TAKE A TEMPORAL
WESTSOUTHWESTWARDS
COMPONENT AND THEN MORE SOUTHWESTWARDS. WITH SOME BETTER UPPER LEVEL
CONDITIONS FOR TUESDAY, WEAKENING TREND IS THEN SLOWERED.
BEYOND 72H, SYSTEM IS EXPECTED TO ACCELERATE TOWARDS THE MID-LAT.
NUMERICAL GUIDANCE IS IN RATHER GOOD AGREEMENT EXCEPT, UKMO AND
ALADIN-REUNION THAT STRONGLY WEAKEN THE SYSTEM AT TAU 24 AND THEN
BRING
IT ON A WESTWARDS TRACK=
NNNN