Tropical Weather Discussion
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AXNT20 KNHC 251150

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
750 AM EDT Fri May 25 2018

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
1130 UTC.


A 1011 mb low along the eastern coast of the Yucatan peninsula
near Chetumal at 19.5N 88.0W is drifting slowly northward over the
eastern Yucatan Peninsula. The low is producing widespread shower
and thunderstorm activity over the far northwest Caribbean west of
83W. Environmental conditions are forecast to become more
conducive for development, and a subtropical or tropical
depression or storm is likely to form during the weekend over the
eastern or central Gulf of Mexico. Please see high seas forecasts
issued by the National Weather Service for information on gale
warnings associated with this system. An Air Force Reserve
reconnaissance aircraft is scheduled to investigate the
disturbance this afternoon, if necessary. Locally heavy rainfall
is forecast across western Cuba and over much of Florida and the
northern Gulf Coast into early next week. In addition, the threat
of rip currents will steadily increase along the Gulf coast from
Florida westward to Louisiana over the Memorial Day weekend. For
more information on these threats, please see products issued by
your local weather office. The chance for tropical cyclone
formation during the next 48 hours is high. The chance for
tropical cyclone formation during the next 5 days is high.

A gale warning is in effect in the meanwhile for the Gulf of
Mexico starting 1200 UTC Sat May 26 within 90 nm E semicircle of
1006 mb low centered near 22.5N87W with 30 to 35 kt winds, and
seas 8 to 11 ft.


A tropical wave is moving eastward at 10 to 15 kt through French
Guiana with the axis extending northward to 12N. The wave is in a
moderate moist environment that is supporting isolated showers
within 150 nm either side of the wave axis.


The monsoon trough extends from the coast of Guinea, Africa near
11N14W and continues to 04N20W. The ITCZ continues from 04N20W to
00N30W to 00N50W. Scattered moderate to isolated strong
convection is along the coast of W Africa from 02N to 08N between
10W and 20W. Isolated moderate convection is within 180 nm either
side of the ITCZ.



A surface trough extends from low pressure along the coast of
the Yucatan peninsula northward to the 26N87W in the eastern Gulf
of Mexico. Isolated moderate convection is within 120 nm east of
the trough, and over the Straits of Florida, portions of Florida,
and the N Gulf coast E of Texas. Mostly fair weather is over the
W Gulf. Light to gentle winds are in the western half of the basin
with seas in the range of 2 to 3 ft.

The low over the Yucatan peninsula is expected to develop into a
a tropical cyclone as it moves slowly northward through Mon. Gale
conditions and seas around 12 ft are now expected starting Sat in
the SE Gulf, spreading northward and reaching the N central Gulf
through Mon. Winds and seas will diminish on Tue. Please read the
Special Features section above.


Moderate to fresh tradewinds are over the E Caribbean with mostly
fair weather. Aside from the showers and thunderstorms mentioned
above related to the low pressure over Mexico, scattered showers
and thunderstorms are also active from the central coast of
Colombia to near San Andres Island in the southwest Caribbean. A
few trade wind showers are noted elsewhere.

The surface low over the Yucatan peninsula will drift northward
into the Gulf of Mexico today. Fresh to locally strong SE winds
and peak seas near 8 ft are expected the NW Caribbean through Sat
as this low potentially develops into a tropical cyclone. High
pressure in the central Atlc will maintain fresh to strong trade
winds in the Caribbean through Sat with strongest winds along the
coast of Colombia before weakening somewhat on Sun through early
next week.


Scattered showers are over the northern Bahamas. The remainder of
the Atlantic is under the influence of a broad surface ridge
centered by a 1026 mb high near 32N36W. This high is supporting
moderate winds in the Bahamas Bank and Atlantic passages to the

Over the W Atlantic moderate to fresh tradewinds are expected S
of 27N through Monday. SE to S winds will increase to fresh to
locally strong W of 77W Sat night through Sun night as developing
low pres in the Gulf of Mexico tightens the pressure gradient.

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