|
|
MFR09Z升格熱帶低壓WTIO30 FMEE 200640
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 2/16/20202021
1.A TROPICAL DEPRESSION 16
2.A POSITION 2021/04/20 AT 0600 UTC:
WITHIN 20 NM RADIUS OF POINT 11.0 S / 52.4 E
(ELEVEN DECIMAL ZERO DEGREES SOUTH AND
FIFTY TWO DECIMAL FOUR DEGREES EAST)
MOVEMENT: WEST 12 KT
3.A DVORAK ANALYSIS: 2.5/2.5/D 1.0/24 H
4.A CENTRAL PRESSURE: 1003 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 30 KT
RADIUS OF MAXIMUM WINDS (RMW): 37 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 0 SE: 95 SW: 0 NW: 0
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1010 HPA / 200 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM
1.B FORECASTS (WINDS RADII IN KM):
12H: 2021/04/20 18 UTC: 10.6 S / 50.1 E, VENT MAX= 035 KT, MODERATE
TROPICAL STORM
28 KT NE: 0 SE: 370 SW: 315 NW: 0
34 KT NE: 0 SE: 220 SW: 185 NW: 0
24H: 2021/04/21 06 UTC: 9.9 S / 48.4 E, VENT MAX= 040 KT, MODERATE
TROPICAL STORM
28 KT NE: 75 SE: 370 SW: 315 NW: 185
34 KT NE: 0 SE: 220 SW: 185 NW: 0
36H: 2021/04/21 18 UTC: 9.8 S / 47.1 E, VENT MAX= 045 KT, MODERATE
TROPICAL STORM
28 KT NE: 75 SE: 370 SW: 315 NW: 185
34 KT NE: 75 SE: 220 SW: 185 NW: 75
48H: 2021/04/22 06 UTC: 9.7 S / 45.9 E, VENT MAX= 050 KT, SEVERE
TROPICAL STORM
28 KT NE: 75 SE: 370 SW: 315 NW: 185
34 KT NE: 110 SE: 220 SW: 185 NW: 110
48 KT NE: 20 SE: 35 SW: 35 NW: 20
60H: 2021/04/22 18 UTC: 9.6 S / 45.1 E, VENT MAX= 040 KT, MODERATE
TROPICAL STORM
28 KT NE: 75 SE: 370 SW: 315 NW: 185
34 KT NE: 75 SE: 220 SW: 185 NW: 75
72H: 2021/04/23 06 UTC: 9.5 S / 44.7 E, VENT MAX= 035 KT, MODERATE
TROPICAL STORM
28 KT NE: 0 SE: 370 SW: 315 NW: 0
34 KT NE: 0 SE: 220 SW: 185 NW: 0
2.B LONGER-RANGE OUTLOOK:
96H: 2021/04/24 06 UTC: 9.7 S / 43.3 E, VENT MAX= 025 KT, FILLING UP
120H: 2021/04/25 06 UTC: 8.9 S / 40.1 E, VENT MAX= 020 KT, FILLING UP
2.C ADDITIONAL INFORMATION:
T=CI=2.5
THE CIRCULATION THAT HAS BEEN MONITORED SINCE LAST WEEK VIA THE
RSMC'S ITCZ BULLETINS, WHILE CIRCULATING NEAR THE CHAGOS, HAS
EXPERIENCED A TEDIOUS DEVELOPMENT DURING ITS WESTWARD TRACK, IN A TOO
DRY ENVIRONMENT LINKED TO THE DRY PHASE OF THE MJO AND WITH A LACK OF
EQUATORWARD CONVERGENCE. HOWEVER, SINCE YESTERDAY SUNDAY AND MONDAY,
AND ESPECIALLY THE LAST NIGHT, IT SHOWS SIGNS OF BETTER ORGANIZATION,
AS IT TRACKS TOWARDS THE NORTH OF MADAGASCAR THIS THUESDAY.
THE DEEP CONVECTION OF MODERATE INTENSITY IS STILL QUITE FLUCTUATING,
AND MAINLY PRESENT IN THE NORTH-WEST SEMICIRCLE.
THE LAST ASCAT SWATHS OF THE LAST NIGHT INDICATE WINDS OF 30 KT, VERY
LOCALLY 35KT, IN THE SOUTHEASTERN SEMICIRCLE OF THE SYSTEM, UP FROM
THE PREVIOUS DAYS, BUT WITH A STRUCTURE THAT REMAINS ASYMMETRIC
(SIGNIFICANTLY WEAKER WINDS IN THE NORTHWESTERN SEMICIRCLE). THE
SSMIS MICROWAVE PASS OF 0103Z SHOWS THE BEGINNING OF AN ORGANIZATION
OF THE SYSTEM, WITH THE BEGINNINGS OF A CURVED BAND IN THE NORTHERN
SEMICIRCLE OF THE CIRCULATION.
THERE IS A GOOD AGREEMENT BETWEEN MODELS ABOUT THE SYSTEM'S TRACK
UNTIL WEDNESDAY, WITH A WESTWARD MOVEMENT ON THE NORTHERN SIDE OF THE
LOW TROPOSPHERIC SUBTROPICAL RIDGE, TRACKING IMMEDIATELY SOUTH OF THE
FARQUHAR ATOLL AND OFF NORTHERN MADAGASCAR. FROM WEDNESDAY AND
THURSDAY, WHEN THE SYSTEM WILL REACH THE NORTH OF THE MOZAMBIQUE
CHANNEL AND OFF THE COMOROS, THE STEERING FLOWS BECOME WEAKER AND THE
TRAJECTORY IS MORE UNCERTAIN , MARKING A SLOWDOWN, EVEN A LOOP ON
SOME MODELS IN THE NORTH OF THE COMOROS. IN CONSEQUENCES, THE MORE OR
LESS IMPORTANT INFLUENCE ON THE NORTH OF THE COMOROS ARCHIPELAGO
REMAINS TO BE SPECIFIED.
ENVIRONMENTAL CONDITIONS ARE RELATIVELY FAVORABLE TO SHORT TERM
DEVELOPMENT : IN THE LOW LAYERS, A TRADEWINDS SURGE IS ONGOING,
REINFORCED TOMORROW BY THE ACCELERATION RELATED TO THE BYPASS OF THE
NORTHERN TIP OF MADAGASCAR, WHICH SHOULD INCREASE THE POLEWARD LOW
LEVEL CONVERGENCE. HOWEVER, DURING THIS TIME, THE EQUATORWARD
CONVERGENCE REMAINS WEAK TO VERY WEAK, WHICH BRINGS UNCERTAINTY ON
THE MORE OR LESS EFFICIENT CONSOLIDATION OF THE LOW'S INNER CORE.
ALOFT, DEEP SHEAR IS WEAK AND SHOULD REMAIN SO FOR THE NEXT FEW DAYS
(AROUND 10 KT OR LESS), AND NO INTRUSION OF DRY AIR IN THE
MID-TROPOSPHERE SHOULD INTERFERE WITH CONVECTION NEAR THE CORE OF THE
SYSTEM UNTIL WEDNESDAY. UPPER-TROPOSPHERIC DIVERGENCE IS QUITE GOOD
WITH A TEMPORARY LIGHT EQUATORWARD OUTFLOW CHANNEL IN THE SHORT RUN
ON THUESDAY, THEN, FROM MID-WEEK, AN INCREASE OF UPPER DIVERGENCE ON
THE EDGE OF A SUBTROPICAL TROUGH CIRCULATING FURTHER SOUTH. ON THE
OTHER HAND, THE OCEANIC POTENTIAL IS PRESENT WITH SST AROUND 28-29C
AND A GRADUAL INCREASE OF THE DEPTH OF THE ISO-26C, BECOMING HIGHER
IN THE NORTH OF THE MOZAMBIQUE CHANNEL. THUS, CONDITIONS SEEM TO BE
GATHERED FOR MODERATE INTENSIFICATION UNTIL WEDNESDAY, PROBABLY UNTIL
THE STAGE OF A MODERATE TROPICAL STORM OR EVEN SEVERE TROPICAL STORM.
FROM THURSDAY, THE INCREASE OF THE NORTH TO NORTH-WESTERLY SHEAR
ALONG A TROUGH PASSING OVER THE SOUTH OF MADAGASCAR SHOULD TILT THE
CONVECTIVE CORE AND WEAKEN IT BY ADVECTING DRY AIR. THIS SHOULD LEAD
TO THE WEAKENING OF THE SYSTEM IN THE SECOND PART OF THE WEEK.
THE SMALL SIZE OF THE LOW'S CORE, MAKING IT VERY REACTIVE TO ITS
ENVIRONMENT, INDUCES A HIGHER THAN AVERAGE UNCERTAINTY ON THE PRESENT
INTENSITY FORECAST. 
|
|
提升卡
千斤頂
