NHC Tropical Weather Discussion (Atlantic): National Hurricane Center – Tropical Weather Discussion (Atlantic)
AXNT20 KNHC 141759
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
159 PM EDT Tue Aug 14 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 1200 UTC surface analysis and satellite imagery through
A low pressure system centered near 37N47W is producing a large
area of cloudiness and disorganized thunderstorms east of the
center. Environmental conditions may become conducive for some
development by Wednesday. The system is forecast to move NE over
colder waters Thursday and Friday. There is medium potential for
this low to become a subtropical cyclone during the next 48
An Atlantic Ocean tropical wave is along 30W, from 08N to 20N,
moving west at 15 kt. Scattered rain showers are in the monsoon
trough area from 07N to 10N between 26W and 33W.
An Atlantic Ocean tropical wave is along 52W from 08N to 21N,
moving west at 15-20 kt. Scattered moderate convection is in the
monsoon trough area from 07N to 09N between 46W and 55W.
A Caribbean Sea tropical wave is along 70W from 10N to 22N,
moving west at 15-20 kt. Scattered moderate convection is along
the coast of N Hispaniola from 18N to 22N between 68W and 72W.
A Caribbean Sea tropical wave is along 82W from 10N to 22N,
moving west at 15 kt. The wave is enhancing scattered moderate to
isolated strong convection along the monsoon trough south of 12N.
The monsoon trough extends from the coast of Africa near 11N15W
to 10N30W to 09N42W. The ITCZ continues from 09N42W to 08N450W to
the coast of South America near 06N55W. Scattered moderate
convection is from 06N to 09N between 37W and 41W.
GULF OF MEXICO…
An upper level cyclonic circulation is over southern Mexico near
18N100W. Isolated showers are over the area. Upper level cyclonic
wind flow covers the Gulf of Mexico south of 24N and west of 90W.
A broad upper level anticyclonic circulation centered near 28N94W
spans the rest of the area. Widely scattered moderate rain
showers are over the NE Gulf from 26N to 31N between 82W and 87W.
On the surface a surface trough is over the NE Gulf from 31N86W
to 28N90W. Another surface trough is over the Bay of Campeche
from 20N95W to 17N94W. Scattered showers are within 90 nm of the
A nocturnal trough will develop during the evening hours in the
Yucatan Peninsula, before pushing offshore into the SW Gulf each
night. A surge of fresh to occasionally strong NE to E winds will
accompany this trough. The trough will become weaker by the middle
of the week, allowing the winds to diminish. A surface ridge will
support light to moderate E to SE winds across the remainder of
the basin through Friday night.
An upper level cyclonic circulation is along the coast of N Cuba
near 23N78W. Upper level diffluence is over Hispaniola enhancing
convection. Another upper level cyclonic circulation is over the
NW Caribbean near 19N85W. Upper level diffluence is over Honduras
and Nicaragua enhancing convection.
The monsoon trough is along 09N between 73W and 85W. Scattered
moderate to isolated strong convection is S of 12N between 74W and
84W, to include N Colombia, Panama, and Costa Rica.
Surface high pressure north of the area will maintain fresh to
strong winds in the south central Caribbean Sea through tonight.
Winds along the coast of Colombia and in the Gulf of Venezuela,
have begun to subside, and continue during the middle of the week
as western Atlantic Ocean high pressure slowly weakens.
An upper level trough is off the coast of N Florida. Scattered
showers are over the W Atlantic N of the N Bahamas and W of 77W.
A large upper level anticyclonic circulation is centered over the
W Atlantic near 33N59W. Upper level diffluence E of the center is
enhancing convection near 29N50W.
A surface ridge extends from a 1023 mb high pressure center near
30N67W to N Florida. The tail end of a surface trough extends
from 32N50W to 26N55W. Scattered moderate convection is within 90
nm of the trough. Another 1025 mb high is over the E Atlantic
near 38N25W producing fair weather.
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