Tropical Weather Discussion
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000
AXNT20 KNHC 251158
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
758 AM EDT Wed Apr 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
1115 UTC.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic Ocean near the Sierra
Leone/Liberia border and continues to 03N16W. The ITCZ extends
from 03N16W to 01N30W to the Equator at 50W. Scattered moderate
to isolated strong convection is noted within 120 nm N of ITCZ
axis between 20N-26N. Scattered moderate convection is observed
from the Equator to 04.5N between 32W and 38W, and from 02N-05N
between 40W-45W.

...DISCUSSION...

GULF OF MEXICO...

A weak cold front extends from the Florida Keys southwest to
23N88W, where it becomes stationary to the eastern Bay of
Campeche and to Mexico near 18N94W as of 06Z. Scattered showers
and tstms are noted ahead of the cold front. Gentle to moderate
northerly winds are noted behind the front over the eastern half
of the Gulf. A 1018 mb high pressure, located over the NW gulf
follows the front. It is forecast to move to along NW Cuba and
the Yucatan Basin this morning, and become diffuse tonight.
Another weak cold front will reach the Texas coast tonight, and
move across the northwest and north-central waters Thu and Thu
night, then over the eastern gulf late Thu night through Fri night
as it slows down. This front will then exit the southeast gulf on
Sat followed by weak high pres that will become centered over the
northwest gulf. The high pres will slide eastward to the far
north-central gulf by Sun night.

CARIBBEAN SEA...

A cold front extending across the Florida Keys and the SE Gulf of
Mexico will move across western Cuba today increasing the likelihood
of showers and tstms. Currently, scattered showers and tstms are
noted in association with the frontal boundary. The front is
forecast to become diffuse tonight.

Latest satellite derived winds and seas and an overnight ASCAT
pass reveal moderate to fresh trades over the south-central
Caribbean, with the exception of fresh to strong trades within 90
nm of the coast of Colombia. Gentle to moderate trades are evident
elsewhere across the Caribbean as well as across the tropical N
Atlantic waters. Seas are in the 6-8 ft range over the south-
central Caribbean, 2-3 ft over the western Caribbean, and 3-5 ft
over the remainder of the Caribbean waters. Seas in the 5-6 ft
range prevail across the tropical N Atlantic waters. The gentle to
moderate trades will pulse to fresh to strong mainly over the
south-central Caribbean during the overnight hours through the
rest of the week. Elsewhere, gentle to moderate trades will
continue through the period. Shallow moisture embedded in the
trade wind flow will move across the Lesser Antilles producing
isolated to scattered passing showers.

ATLANTIC OCEAN...

A cold front extends from 31N76W southwest to SE Florida and the
Florida Keys as of 06Z. Latest satellite derived winds and buoys
indicate fresh to strong SE to S winds to the east of the front
north of 27N between 72W and 7tW. Latest altimeter data shows
seas in the range of 8-10 ft associated with these winds.
Scattered showers and thunderstorms, with frequent lightning, are
occurring ahead of the front, particularly over the NW Bahamas,
and north of 27N and W of 70W. The cold front will begin to slow
down as it reaches from near 31N76W to to the Straits of Florida
by early this afternoon, from near 31N75W to NW Cuba tonight then
stall into Thu and dissipate. The strong SE to S winds will shift
northeast of the forecast waters tonight.

A second weak cold front will move over the northwest waters Fri
night. This front will reach from near 31N72W to the Straits of
Florida Sat night, and from near 31N66W to 25N72W to west-central
Cuba by Sun night. Weak high pressure will build across the area
behind the front, with generally gentle to moderate west to northwest
flow expected in the wake of this front.

A stationary front enters the forecast area near 31N48W and continues
SW to near 26N62W. Moderate to fresh NE-E winds are blowing behind
the front based on scatterometer data. The remainder of the Atantic
Ocean is under the influence of a 1030 mb high pressure located
just SW of the Azores near 36N26W.



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

$$
GR



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