WTIO30 FMEE 170628



RSMC / TROPICAL CYCLONE CENTER / LA REUNION

TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)



0.A WARNING NUMBER: 11/5/20152016

1.A TROPICAL CYCLONE  5  (URIAH)



2.A POSITION 2016/02/17 AT 0600 UTC:

WITHIN 10 NM RADIUS OF POINT 18.2 S / 80.9 E

(EIGHTEEN    DECIMAL TWO   DEGREES SOUTH AND EIGHTY    DECIMAL NINE

DEGREES EAST)

MOVEMENT : WEST 8 KT



3.A DVORAK ANALYSIS: 5.0/5.0/D 1.0/12 H



4.A CENTRAL PRESSURE: 963 HPA

5.A MAX AVERAGE WIND SPEED (10 MN): 80 KT

RADIUS OF MAXIMUM WINDS (RMW) :37 KM



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

28 KT NE: 300 SE: 460 SW: 650 NW: 280

34 KT NE: 200 SE: 310 SW: 350 NW: 170

48 KT NE: 110 SE: 130 SW: 150 NW: 70

64 KT NE: 70 SE: 80 SW: 80 NW: 60



7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1006 HPA / 700 KM

8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP



1.B FORECASTS:

12H: 2016/02/17 18 UTC: 18.8 S / 79.5 E, MAX WIND=095 KT, INTENSE

TROPICAL CYCLONE

24H: 2016/02/18 06 UTC: 20.1 S / 78.5 E, MAX WIND=100 KT, INTENSE

TROPICAL CYCLONE

36H: 2016/02/18 18 UTC: 21.1 S / 78.3 E, MAX WIND=095 KT, INTENSE

TROPICAL CYCLONE

48H: 2016/02/19 06 UTC: 22.0 S / 78.5 E, MAX WIND=090 KT, INTENSE

TROPICAL CYCLONE

60H: 2016/02/19 18 UTC: 22.2 S / 78.6 E, MAX WIND=085 KT, TROPICAL

CYCLONE

72H: 2016/02/20 06 UTC: 22.5 S / 78.6 E, MAX WIND=080 KT, TROPICAL

CYCLONE



2.B LONGER-RANGE OUTLOOK :

96H: 2016/02/21 06 UTC: 23.3 S / 78.6 E, MAX WIND=060 KT, SEVERE

TROPICAL STORM

120H: 2016/02/22 06 UTC: 25.0 S / 79.5 E, MAX WIND=045 KT, MODERATE

TROPICAL STORM



2.C ADDITIONAL INFORMATION:

T=5.0- CI=5.0



OVER THE LAST 6 HOURS, THE ELONGATED EYE BECAME MORE SYMMETRIC AND

WARMER IN IR, SUGGESTING A RATHER STRONG INTENSIFICATION OF URIAH.

HOWEVER, ON THE LAST IMAGES, THE CLOUD PATTERN TEMPORARILY

DETERIORATE, WITH A WEAKNESS IN THE EASTERN SEMI-CIRCLE, GIVING A T

INFERIOR TO CI. THIS DEEPENING IS DUE TO THE IMPROVEMENT OF THE POLAR

SIDE OUTFLOW AND BY THE PRESENCE OF HIGH POTENTIAL WATERS BENEATH THE

CYCLONE. THIS MORNING ASCAT SWATHS SHOW THAT THE STRONGEST WINDS ARE

LOCATED IN THE SOUTHERN SEMI-CIRCLE, WHERE THE PRESSURE GRADIENT IS

MAXIMAL. THE TRACK STARTED TO SHIFT SOUTHWESTWARDS, SLOWING DOWN.



TOMORROW, WITH THE REBUILDING OF A MID-LEVEL RIDGE IN THE EAST, THE

SYSTEM WILL CONTINUE TO BEND SOUTHWARD. FRIDAY, URIAH IS LIKELY TO

SLOW DOWN BECAUSE OF THE BUILDING OF A MID LEVEL RIDGE IN THE SOUTH.

MODEL GUIDANCE STILL SHOW LARGE SPREAD FROM FRIDAY EVENING,

SUGGESTING AN INCREASED UNCERTAINTY. HOWEVER, THE MAJORITY OF THE

ENSEMBLE MEMBERS AND THE OTHER NWP MODELS FORECAST A SOUTHWARD TRACK

STEERED BY A BAROCLINIC LOW MOVING TOWARDS THE MID-LATITUDES AND

CAUSING A WEAKNESS IN THE SUBTROPICAL RIDGE.



ON THIS TRACK, ACCORDING TO THE LAST TRENDS, THERE IS A HIGH CHANCE

THAT URIAH WILL REACH THE INTENSE TROPICAL CYCLONE INTENSITY THIS

NIGHT, BEFORE LEAVING THE WARMER WATERS, LIMITING ITS STRENGTH. UPPER

LEVELS CONDITIONS SHOULD BECOME PROGRESSIVELY LESS CONDUCIVE WITH A

SLIGHT NORTHWESTERLY VERTICAL WINDSHEAR, INCREASING SATURDAY WITH THE

ARRIVAL OF AN UPPER TROUGH. THEN THE OCEAN HEAT CONTENT SHOULD BE

MARGINAL SOUTH OF 23-24S, LEADING TO A SIGNIFICANT FILING. MOREOVER,

THE SLOW MOTION FORECAST FROM FRIDAY MAY PARTICIPATE IN THE COOLING

OF THE UNDERLYING SST.=