• Indian-S: STS Alicia 18

    From Weather Alert@21:1/175 to All on Mon Nov 16 22:08:00 2020
    WTIO30 FMEE 161746
    RSMC / TROPICAL CYCLONE CENTER / LA REUNION
    TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)

    0.A WARNING NUMBER: 18/1/20202021
    1.A SEVERE TROPICAL STORM 1 (ALICIA)

    2.A POSITION 2020/11/16 AT 1800 UTC:
    WITHIN 20 NM RADIUS OF POINT 16.9 S / 71.9 E
    (SIXTEEN DECIMAL NINE DEGREES SOUTH AND
    SEVENTY ONE DECIMAL NINE DEGREES EAST)
    MOVEMENT: SOUTH-SOUTH-WEST 6 KT

    3.A DVORAK ANALYSIS: 3.0/4.0/W 1.5/12 H

    4.A CENTRAL PRESSURE: 985 HPA
    5.A MAX AVERAGE WIND SPEED (10 MN): 55 KT
    RADIUS OF MAXIMUM WINDS (RMW): 56 KM

    6.A EXTENSION OF WIND BY QUADRANTS (KM):
    28 KT NE: 170 SE: 220 SW: 220 NW: 130
    34 KT NE: 120 SE: 120 SW: 150 NW: 90
    48 KT NE: 90 SE: 90 SW: 110 NW: 70


    7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1006 HPA / 600 KM
    8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION: MEDIUM

    1.B FORECASTS:
    12H: 2020/11/17 06 UTC: 17.9 S / 71.7 E, VENT MAX= 040 KT, MODERATE
    TROPICAL STORM
    24H: 2020/11/17 18 UTC: 19.2 S / 71.1 E, VENT MAX= 035 KT, MODERATE
    TROPICAL STORM
    36H: 2020/11/18 06 UTC: 20.9 S / 70.1 E, VENT MAX= 030 KT, FILLING UP
    48H: 2020/11/18 18 UTC: 21.6 S / 69.0 E, VENT MAX= 025 KT, FILLING UP
    60H: 2020/11/19 06 UTC: 22.0 S / 68.0 E, VENT MAX= 020 KT, FILLING UP

    2.B LONGER-RANGE OUTLOOK:
    NIL

    2.C ADDITIONAL INFORMATION:
    T=3.0- CI=4.0-

    OVER THE LAST SIX HOURS,THE SHEAR PATTERN OF THE LOW IS ALLSO
    CONFIRMED BY LATEST SATELITE IMAGERY. IN AGREEMENT WITH OBJECTIVE
    INTENSITY ANALYSIS (SATCON/ADT), INTENSITY WAS THUS DOWNGRADED TO 55
    KT. MINIMAL ESTIMATED CENTRAL PRESSURE WAS ADJUSTED THANKS TO THE
    BUOY 5601578 CURRENTLY MEASURING ITS MINIMUM OF PRESSURE AROUND
    987HPA AT NEARLY 20NM FROM THE CENTER CLOSE AT 13UTC.

    THE TRACK FORECAST REMAINS DRIVEN BY THE EASTWARD SHIFT OF THE
    SUBTROPICAL RIDGE WHICH INDUCES A POLEWARDS TRACK. IT THEN BECOME
    MORE ZONAL THANKS TO THE ARRIVAL OF THE SUBTROPICAL ANTICYCLONE, WHEN
    THE SYSTEM BECOMES WEAK. THE PROBABILITY OF A FUJIWARA EFFECT WITH
    TROPICAL DEPRESSION 02 SEEMS RATHER LOW DUE TO THE SHORT SIZE OF 02. UNCERTAINTY IS RATHER STRONG NEVERTHELESS WITH MANY EPS MEMBERS OF DETERMINISTIC GUIDANCE SUGGESTING YET A MORE SOUTHEASTWARD TRACK.

    ALICIA HAS STARTED ITS RAPID WEAKENING PHASE DUE TO THE ARRIVAL OF
    DRY AIR ABOVE THE INNER CORE IN RELATION WITH SHEAR. THE DISAPPEARING
    OF THE SUFFICIENT OCEANIC POTENTIAL SHOULD END ANY POSSIBILITY FOR
    RENEWED TROPICAL DEEPENING AND FILL UP THE SYSTEM.
    =
    --- SBBSecho 3.11-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (21:1/175)