Atlantic Tropical Weather Discussion

National Hurricane Center - Tropical Weather Discussion (Atlantic)

  1. 000
    AXNT20 KNHC 231110
    TWDAT

    Tropical Weather Discussion
    NWS National Hurricane Center Miami FL
    710 AM EDT Tue May 23 2017

    Tropical Weather Discussion for North America, Central America
    Gulf of Mexico, Caribbean Sea, northern sections of South
    America, and Atlantic Ocean to the African coast from the
    Equator to 32N. The following information is based on satellite
    imagery, weather observations, radar and meteorological analysis.

    Based on 0600 UTC surface analysis and satellite imagery through
    1015 UTC.

    ...TROPICAL WAVES...

    An Atlantic Ocean tropical wave is along 21W/22W from 12N
    southward, moving westward 15 knots. The area of cyclonic wind
    flow that is associated with this wave ranges between 19W and 23W,
    and the wave was placed in the middle of this range. Convective
    precipitation: scattered strong from 06N to 08N between 20W and
    25W.

    An Atlantic Ocean tropical wave, that was along 39W/40W at 23/0000
    UTC, was re-positioned in order to be along 55W/56W from 12N
    southward. The new position fit the Total Precipitable Water
    imagery, and the Diagnostics forecast data. Convective
    precipitation: any nearby precipitation is part of the ITCZ
    precipitation. widely scattered moderate to isolated strong from
    07N to 09N between 49W and 55W.

    A Caribbean Sea tropical wave is along 75W/76W from 13N southward
    into Colombia, moving westward 10 to 15 knots. Convective
    precipitation: nothing significant. The wave is moving through an
    area of upper level SW wind flow.

    ...ITCZ/MONSOON TROUGH...

    The Monsoon Trough passes through coastal sections of Guinea-
    Bissau near 12N16W, to 10N17W and curving to 08N21W and 06N28W.
    The ITCZ continues from 06N28W to 05N38W and 05N44W. Convective
    precipitation: isolated moderate to widely scattered moderate and
    locally strong from 10N southward from 60W eastward, mostly within
    60 nm on either side of 09N55W 07N35W 04N18W 05N01W.

    ...DISCUSSION...

    ...THE GULF OF MEXICO...

    Upper level NW wind flow spans the area. This NW wind flow is on
    the northwestern side of the NW Caribbean Sea trough. A stationary
    front is in the coastal waters/coastal plains between the Florida
    Pensacola to the Deep South of Texas. Convective precipitation:
    scattered strong from 27N northward from 92W eastward to Florida.

    ...VISIBILITY IN MILES, AND WEATHER, FOR THE OFFSHORE OIL
    PLATFORM SITES, THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N
    NORTHWARD AND FROM 88W WESTWARD...

    KVQT: 1 to 2 and mist.

    KHHV: 2 to 3 and mist.

    KVAF, KGUL, KGBK, KEIR, and KGRY: 3 to 5 and mist.

    KSPR: 2 to 3 and haze.

    VISIBILITY IN MILES, AND WEATHER, FOR THE COASTAL PLAINS OF THE
    U.S.A., FROM THE DEEP SOUTH OF TEXAS TO FLORIDA...

    TEXAS: rainshowers with thunder and some 3 to 4 miles in the Lower
    Valley. 3 miles and mist in Jasper. LOUISIANA: earlier heavy rain
    in the Lake Charles metropolitan area has ended for the moment.
    some light rain and drizzle around Lake Pontchartrain. MISSISSIPPI:
    rainshowers with thunder, and other areas of light rain, from
    Natchez to the Hattiesburg metropolitan area. ALABAMA: light rain
    in the southernmost parts of the state. rain in Mobile and Fort
    Rucker. FLORIDA: light rain from Tallahassee westward. Cross City:
    3 to 5 and mist.

    ...THE CARIBBEAN SEA...

    An upper level trough extends from Cuba to eastern sections of
    Honduras/NE Nicaragua. Upper level SW and W wind flow covers the
    rest of the Caribbean Sea. Convective precipitation: Broken to
    overcast multilayered clouds and possible rainshowers cover the
    Caribbean Sea within 600 nm to the E and SE of the line that runs
    from SE Cuba toward NE Nicaragua.

    The monsoon trough is along 08N70W in NW Venezuela, across Colombia
    and Panama, beyond 10N86W near the western sections of Costa Rica.
    Convective precipitation: scattered to numerous from 11N southward
    to land, between 76W and 78W, reaching the Gulf of Uraba of
    Colombia at times. Other isolated moderate to locally strong from
    13N southward from 76W westward.

    ...HISPANIOLA...

    Upper level SW and W wind flow moves across the area.

    SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: MVFR.
    for the DOMINICAN REPUBLIC: Santo Domingo: VFR. La Romana and
    Punta Cana: VFR. Santiago: VFR. Puerto Plata: VFR.

    The GFS MODEL forecast for 250 mb shows that day one of the
    48-hour forecast will start with a central Cuba-to-eastern
    Honduras/NE Nicaragua trough, and SW and W wind flow moving across
    Hispaniola. The trough will move to Hispaniola by the end of day
    one, bringing cyclonic wind flow to the area. The trough will move
    across and away from Hispaniola during and by the end of day two.
    Expect NW wind flow during and by the end of day two. The GFS
    MODEL forecast for 500 mb shows that an anticyclonic circulation
    center will be to the south of Hispaniola at the beginning of day
    one. SW wind flow will be present for the first 6 hours to 12
    hours, followed by anticyclonic wind flow during the rest of day
    one. Expect anticyclonic wind flow during the first 12 hours to 18
    hours of day two. Expect E to SE winds during the rest of day
    two. The GFS MODEL forecast for 700 mb shows that Hispaniola will
    be on the western end of an Atlantic Ocean-to- Hispaniola east-to-
    west oriented ridge. Expect southerly wind flow during the first
    12 hours or so, followed by SE wind flow.

    ...THE ATLANTIC OCEAN...

    A central Atlantic Ocean upper level trough passes through 32N39W
    to 25N47W and 20N50W and 17N54W. The trough supports a cold front
    that passes through 32N36W to 27N54W and 31N64W. Convective
    precipitation: rainshowers are possible from 23N northward
    between 30W and 80W.

    A surface ridge passes through 32N22W to a 1020 mb high pressure
    center that is near 29N29W, to 22N42W 23N58W, to a 1021 mb high
    pressure center that is near 30N64W. Surface anticyclonic wind
    flow covers the Atlantic Ocean from 15N northward to the area of
    the cold front, between Africa and 80W.

    For additional information please visit
    http://www.hurricanes.gov/marine

    $$
    MT