WTIO30 FMEE 160113



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 6/5/20152016

1.A MODERATE TROPICAL STORM  5  (URIAH)



2.A POSITION 2016/02/16 AT 0000 UTC:

WITHIN 30 NM RADIUS OF POINT 17.3 S / 86.6 E

(SEVENTEEN    DECIMAL THREE   DEGREES SOUTH AND EIGHTY SIX    DECIMAL

SIX   DEGREES EAST)

MOVEMENT : WEST-SOUTH-WEST 8 KT



3.A DVORAK ANALYSIS: 3.0/3.0/W 0.5/24 H



4.A CENTRAL PRESSURE: 991 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 40 KT

RADIUS OF MAXIMUM WINDS (RMW) :87 KM



6.A EXTENSION OF WIND BY QUADRANTS (KM):

28 KT NE: 330 SE: 530 SW: 430 NW: 240

34 KT NE: 190 SE: 410 SW: 310 NW: 190







7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1007 HPA / 1200 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : MEDIUM



1.B FORECASTS:

12H: 2016/02/16 12 UTC: 17.8 S / 84.6 E, MAX WIND=045 KT, MODERATE

TROPICAL STORM

24H: 2016/02/17 00 UTC: 17.9 S / 82.7 E, MAX WIND=055 KT, SEVERE

TROPICAL STORM

36H: 2016/02/17 12 UTC: 18.6 S / 81.0 E, MAX WIND=065 KT, TROPICAL

CYCLONE

48H: 2016/02/18 00 UTC: 19.8 S / 79.8 E, MAX WIND=075 KT, TROPICAL

CYCLONE

60H: 2016/02/18 12 UTC: 21.3 S / 79.2 E, MAX WIND=065 KT, TROPICAL

CYCLONE

72H: 2016/02/19 00 UTC: 22.5 S / 79.1 E, MAX WIND=055 KT, SEVERE

TROPICAL STORM



2.B LONGER-RANGE OUTLOOK :

96H: 2016/02/20 00 UTC: 23.1 S / 78.0 E, MAX WIND=035 KT, MODERATE

TROPICAL STORM

120H: 2016/02/21 00 UTC: 23.6 S / 78.2 E, MAX WIND=035 KT,

POST-TROPICAL DEPRESSION



2.C ADDITIONAL INFORMATION:

T=3.0- CI=3.0



URIAH IS STILL STRUGGLING TO INTENSIFY DUE TO MID-LEVEL DRY AIR

INTRUSION. SPORADIC BURST OF CONVECTION ARE OCCURRING ALONG THE RMW

CURRENTLY AND TRY TO WRAPPED AROUND THE CENTER BUT FAILED TO DO SO.

THE CURRENT INTENSITY IS BASED ON DVORAK WITH GOOD AGREEMENT AMONG

AGENCIES AT 00Z FOR ALL FT=CI=3.0 (40 KT 10 MIN WINDS). PARTIAL

RAPIDSCAT AT 1824Z LAST NIGHT SUGGEST ALSO THIS INTENSITY.



SINCE 21Z (TIME OF THE LATEST AVAILABLE GOOD FIX), THE SYSTEM SEEMS

TO HAVE BEND WEST-SOUTH-WESTWARDS.THIS EXPECTED TREND IS DUE TO A

BULDING LOW TO MID-LEVELS SUBTROPICAL RIDGE LOCATED ON ITS SOUTH IN

THE WAKE OF A TROUGH THAT HAVE BYPASS THE SYSTEM YESTERDAY. FROM

WEDNESDAY, THE SYSTEM WILL PROGRESSIVELY MOVE TOWARDS THE

SOUTH-SOUTH-WEST, WITH THE REBUILDING OF A MID-LEVEL RIDGE IN THE

EAST. FOR THE END OF THE WEEK, URIAH IS LIKELY TO SLOWDOWN BECAUSE OF

THE BUILDING OF ANOTHER RIDGE IN THE SOUTH. BEYOND 4 DAYS, THE EURO

ENSEMBLE FORECAST SHOW LARGE SPREAD SUGGESTING INCREASING

UNCERTAINTY. HOWEVER, A RESUME OF A GRADUAL POLEWARDS TRACK TOWARDS A

NEW WEAKNESS IN THE SUBTROPICAL RIDGE SEEMS TO BE THE MOST LIKELY

SOLUTIONS AS REGARDS TO THE ENSEMBLE AND ALL DETERMINISTIC NUMERICAL

GUIDANCE.





ON THIS TRACK, UPPER LEVELS CONDITIONS SHOULD REMAIN CONDUCIVE UP TO

THURSDAY WITH A WEAK VERTICAL WINDSHEAR. CURRENT BURST OF CONVECTION

NEAR THE "INNER-CORE" OF URIAH SHOULD ALLOW A RESUME OF A GRADUAL

INTENSIFICATION . ON WEDNESDAY, THE BUILDING OF AN OUTFLOW CHANNEL ON

THE POLAR SIDE ALONG WITH GOOD OCEANIC HEAT CONTAIN NEAR 80E, ARE

LIKELY TO HELP THE SYSTEM INTENSIFYING MORE RAPIDLY. AFTER THURSDAY,

THE ARRIVAL OF AN UPPER TROUGH WILL INCREASE THE NORTH-WESTERLY VWS,

AND START THE WEAKENING, ACCENTUATED BY THE MARGINAL OCEAN HEAT

CONTENT SOUTH OF 23-24S. THE SLOW MOTION EXPECTED ON FRIDAY AND

BEYOND IS EXPECTED TO COOL SIGNIFICANTLY THE SST AND INCREASE THE

WEAKENING TREND.=