Atlantic Tropical Weather Discussion

National Hurricane Center - Tropical Weather Discussion (Atlantic)

  1. 000
    AXNT20 KNHC 232236
    TWDAT

    Tropical Weather Discussion
    NWS National Hurricane Center Miami FL
    636 PM EDT Fri Jun 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 1800 UTC surface analysis and satellite imagery through
    2145 UTC.

    ...TROPICAL WAVES...
    Tropical wave extends from 08N27W to 20N24W moving W at 15-20 kt.
    The wave coincides with a relatively sharp 700 mb trough between
    21W-30W and an area of maximum 850 mb relative vorticity along the
    axis from 11N-20N. With the Saharan dust in place over much of
    the eastern Atlc waters E of 45W...only isolated moderate
    convection is occurring in the vicinity of 10N27W embedded within
    the ITCZ and near 24N21W at the northern extent of the wave.

    Tropical wave extends from 04N48W to 13N48W moving W at 15-20 kt.
    Broad and low-amplitude 700 mb troughing is noted between 45W-52W
    with 850 mb relative vorticity maximized along the wave axis near
    10N. Widely scattered moderate convection is from 04N-13N between
    46W-52W.

    Tropical wave extends from 04N66W to 15N64W moving W at 15 kt.
    The wave is moving within the southwestern periphery of 700 mb
    troughing over the eastern Caribbean Sea and an area to the NE of
    the Lesser Antilles to near 22N55W. This broad troughing aloft has
    allowed wave energy to fracture to the NE of the axis and thus is
    analyzed as a weak surface trough from 16N63W to 20N57W.
    Scattered moderate convection remains mostly contained S of 12N
    between 61W-67W across eastern Venezuela and Trinidad this
    evening...however isolated showers are also possible from 13N-20N
    between 56W-67W across Caribbean and Atlc waters.

    Tropical wave extends from 11N91W to 19N89W moving W at 15-20 kt.
    The wave coincides with subtle 700 mb troughing between 86W-92W as
    it approaches a developing area of low pressure centered S-SW of
    the Gulf of Tehuantepec in the East Pacific waters near 13N96W. As
    the energy of the wave becomes absorbed into the low pressure area
    during the next 24 to 36 hours...it will likely continue to
    provide a focus for scattered showers and tstms across portions of
    Central America and southern Mexico. In addition...an upper level
    low is centered 20N91W that is providing ample lifting dynamics
    across the area to support continued convection. Widely scattered
    moderate convection is from 12N-23N between 81W-92W.

    ...MONSOON TROUGH/ITCZ...
    The Monsoon Trough extends from 13N17W to 09N24W. The
    Intertropical Convergence Zone axis extends from 09N24W to 03N39W
    to 05N48W to 06N54W. Aside from convection associated with the
    tropical waves...scattered moderate convection is from 01N-06N
    between 40W-45W...and S of 07N between 53W-57W across interior
    portions of French Guiana and Suriname.

    ...DISCUSSION...

    GULF OF MEXICO...
    Surface ridging extends from the SW North Atlc anchored by a 1021
    mb high centered near 30N68W W-SW to near Brownsville Texas this
    evening. The ridge supports moderate to fresh S-SE winds across
    the basin that are forecast to shift E-SE on Saturday as the
    ridge retreats E Saturday night into Sunday. While the ridge is
    providing overall fair conditions for the northern Gulf...an upper
    level low is centered over the SW Gulf waters near 20N91W. Middle
    to upper level lifting dynamics are generating isolated showers
    and tstms across the SE and S-central Gulf this evening S of 25N
    between 82W-90W. By Saturday night into Sunday...a weak frontal
    boundary is expected to impact the northern waters as it stalls
    along 30N and dissipates by Sunday night.

    CARIBBEAN SEA...
    An upper level low is centered over the SW Gulf of Mexico near
    20N91W supporting widely scattered showers and tstms across
    portions of Central America and the NW Caribbean waters generally
    N of 12N W of 81W. The presence of a tropical wave across the
    Yucatan peninsula and Guatemala is providing additional focus for
    this convective activity. Farther east...another tropical wave is
    analyzed across the SE Caribbean generating scattered showers and
    isolated tstms S of 12N between 61W-65W. Energy from the wave
    continues to fracture to the NE of the axis as a weak surface
    trough extends from 16N63W to 21N57W. Both the northern extent of
    the wave and the surface trough are generating isolated showers
    occurring across much of the eastern Caribbean waters...Puerto
    Rico...the US/UK Virgin Islands...and Lesser Antilles.
    Otherwise...moderate to fresh trades are expected to persist
    overnight and gradually strengthen into fresh to strong breeze
    levels Saturday across the central waters. Little change is
    expected thereafter for the early portion of next week.

    ...HISPANIOLA...
    Mostly clear skies prevail currently across the island this
    evening as surface ridging to the N across the SW North Atlc
    remains in place providing mostly fair weather conditions. In
    addition...an upper level anticyclone centered N of the island is
    continuing to provide NE flow aloft and an environment of overall
    subsidence.

    ATLANTIC OCEAN...
    An upper level anticyclonic circulation is centered offshore of NE
    Florida near 29N78W that continues to support a 1021 mb high
    centered SW of Bermuda near 30N68W. Most cloudiness and isolated
    showers and tstms remain N of 30N between 63W-71W...with
    generally gentle to moderate winds prevailing within the southern
    periphery of the ridging. Otherwise...the remainder of the
    central and eastern Atlc is under the influence of surface ridging
    anchored by a 1023 mb high centered near 34N47W and a 1029 mb high
    centered N of the Azores near 40N26W. Water vapor imagery
    indicates a middle to upper level low is centered near 26N53W and
    is inducing a weak surface trough extending from 24N49W to 27N46W.
    Isolated showers and possible tstms are occurring from 24N-29N
    between 46W-52W.

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

    $$
    HUFFMAN