Atlantic Tropical Weather Discussion

National Hurricane Center - Tropical Weather Discussion (Atlantic)

  1. 000
    AXNT20 KNHC 010452
    TWDAT

    Tropical Weather Discussion
    NWS National Hurricane Center Miami FL
    1252 AM EDT Mon May 1 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 0000 UTC surface analysis and satellite imagery through
    0415 UTC.

    ...SPECIAL FEATURES...
    A vigorous middle to upper level low is centered over the mid-
    Mississippi River valley this evening supporting a cold front
    extending into the Gulf of Mexico from the SE Louisiana coast near
    29N90W S-SW to 24N93W to the southern Mexico coast near 18N93W.
    Scattered showers and tstms are occurring N of 27N between 86W and
    the frontal boundary. In addition to the convection...near gale to
    gale force N-NW winds are occurring offshore of Veracruz and are
    expected to persist through the overnight hours. See the latest
    NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02
    KNHC for more details.

    ...ITCZ/MONSOON TROUGH...
    The Monsoon Trough extends from the Africa coast near 10N14W to
    04N21W. The Intertropical Convergence Zone axis extends from
    04N21W to the Equator near 35W. A surface trough is analyzed from
    01N22W to 09N21W and likely very weak energy that propagated off
    of western Africa the middle of last week. Widely scattered
    moderate convection is from S of 06N between 17W-42W.

    ...DISCUSSION...

    GULF OF MEXICO...
    As mentioned in the Special Features section above...a vigorous
    middle to upper level low centered over the central CONUS supports
    a cold front extending from SE Louisiana near 30N90W to 24N93W to
    the southern Mexico coast near 18N93W. Aside from the near gale to
    gale force winds occurring offshore of Veracruz...strong northerly
    winds are noted generally S of 27N west of the front. To the east
    of the front...primarily gentle to moderate S-SE winds prevail.
    Most ongoing convection is associated with a squall line extending
    from the far western Florida panhandle to the cold front near
    28N90W. The northern portion of the cold front will continue
    sweeping eastward while the southern extent will begin to
    stall Monday into Tuesday. High pressure will build in behind the
    front across the western Gulf supporting moderate to occasional
    fresh E-NE winds through mid-week. Otherwise by Tuesday night...
    moderate E-SE winds will increase to fresh levels across the
    western waters into Wednesday as an area of low pressure develops
    across Texas and moves E-NE across the lower Mississippi River
    valley the second half of the week.

    CARIBBEAN SEA...
    Most of the Caribbean basin is under the influence of dry and
    relatively stable NW flow aloft on the eastern periphery of an
    upper level anticyclone centered over southern Honduras near
    13N87W. However...middle to upper level troughing is noted in the
    vicinity of 20N69W N of Hispaniola. This troughing is generating
    area of widely scattered showers and isolated tstms N of 16N
    between 60W-70W. The troughing aloft is expected to remain nearly
    stationary N of Hispaniola through Tuesday night and then weaken
    and shift N as the aforementioned ridging moves eastward over
    western portions of the basin. Otherwise...moderate to fresh
    trades prevail and are expected to persist through Tuesday night
    as high pressure remains anchored to the N across the SW North
    Atlc region.

    ...HISPANIOLA...
    Currently widely scattered showers and isolated tstms are
    occurring across eastern portions of the island and the adjacent
    coastal waters generally E of 70W. This activity is due in large
    part to a middle to upper level trough focused in the vicinity of
    20N69W. The troughing aloft is expected to remain nearly
    stationary through Tuesday night with higher probability of
    precipitation and convection remaining in the forecast through
    early Wednesday until the upper level feature is expected to
    weaken and move northward.

    ATLANTIC OCEAN...
    Much of the SW North Atlc is under the influence of a surface
    ridge anchored by a 1026 mb high centered W of Bermuda near
    32N69W. One exception to the ridge is an area of widely scattered
    showers and isolated tstms occurring S of 24N between 60W-70W in
    association with an middle to upper level trough noted on water
    vapor imagery in the vicinity of 20N69W. This feature is expected
    to remain nearly stationary through Tuesday night and then
    gradually weaken into Wednesday. Cloudiness and probability of
    precipitation and convection are forecast to increase for the
    Turks and Caicos...along with portions of the SE Bahamas the next
    few days. Farther east...a middle to upper level trough over the
    central North Atlc supports a cold front that remains to the N of
    the discussion area...however pre-frontal troughing dips S to 29N
    between 40W-58W. Isolated showers are possible across this area
    as the front continues to approach 30N. The remainder of the
    eastern Atlc is under the influence of a surface ridge anchored by
    a 1024 mb high centered near 32N27W.

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

    $$
    HUFFMAN