Tropical Weather Discussion by NHC
046
AXNT20 KNHC 251755
TWDAT
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
155 PM EDT Sat Aug 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 1200 UTC surface analysis and satellite imagery through
1730 UTC.
...TROPICAL WAVES...
An Atlantic Ocean tropical wave is along 25W/26W from 20N
southward. Isolated moderate rainshowers are from 10N to 13N
between 27W and 30W.
An Atlantic Ocean tropical wave is along 34W/35W from 19N
southward. This wave was added to the 25/1200 UTC map analysis
based on long loop satellite imagery and computer model
diagnostics. Broken to overcast multilayered clouds and possible
rainshowers cover the area that is from 14N to 24N between 30W and
40W.
An Atlantic Ocean tropical wave is along 52W/53W from 19N
southward. Rainshowers are possible from 14N to 21N between 50W
and 62W.
A Caribbean Sea tropical wave is along 70W/71W from 18N
southward. This wave is moving into an area of pre-existing upper
level cyclonic wind flow. Rainshowers are possible within 120 nm
on either side of the wave.
A Caribbean Sea tropical wave is along 86W/87W from 20N
southward, passing through Honduras and Nicaragua. Broad upper
level cyclonic wind flow spans the western Caribbean Sea, with
upper level cyclonic circulation centers and troughs. Widely
scattered moderate to isolated strong rainshowers are in the
waters that are from 80W westward. Isolated moderate rainshowers
are elsewhere from the Windward Passage westward.
...MONSOON TROUGH/ITCZ...
The monsoon trough passes through the coastal sections of Senegal
near 14N17W, to 10N23W, 09N30W, 08N36W, and 07N39W. The ITCZ
continues from 07N39W to 05N45W and 05N50W. Precipitation: widely
scattered moderate to isolated strong rainshowers are from 04N to
11N between 30W and 44W, and from 05N to 07N between 50W and 53W.
Isolated moderate rainshowers are elsewhere from 13N southward
from 60W eastward.
...DISCUSSION...
GULF OF MEXICO...
The southernmost part of a stationary front passes through 33N77W
to 31N81W near the coast of SE Georgia. A narrow NE-to-SW oriented
upper level trough extends from 32N81W near the South Carolina/
Georgia border, across NE Florida, to 28N83W in the NE corner of
the Gulf of Mexico, to 23N88W in the Gulf of Mexico. An upper
level cyclonic circulation center is near 23N75W, on top of the
central Bahamas. A second cyclonic circulation center is near
29N67W. Widely scattered moderate to isolated strong rainshowers
are to the west of the line that passes through 33N70W 27N75W
22N76W. Isolated moderate rainshowers are elsewhere from 70W
westward. Isolated moderate rainshowers are in the Gulf of Mexico
from 94W eastward.
A surface trough will develop during the evening hours in the
Yucatan Peninsula, before pushing offshore into the SW corner of
the Gulf of Mexico each night. A surge of moderate to fresh NE to
E winds will accompany this trough. A surface ridge will dominate
the rest of the Gulf waters, supporting a gentle to moderate wind
flow.
CARIBBEAN SEA...
An upper level trough extends from an Atlantic Ocean 23N62W cyclonic
circulation center, into the NE corner of the Caribbean Sea near
18N63W and 16N70W. Isolated moderate rainshowers are from 70W
eastward.
An upper level inverted trough extends from the SW corner of the
Caribbean Sea, across Nicaragua and Honduras, to the southern half
of the coast of the eastern side of the Yucatan Peninsula. Widely
scattered moderate to isolated strong rainshowers are in the
waters that are from 80W westward. Isolated moderate rainshowers
are elsewhere from the Windward Passage westward.
Fresh to strong winds and building seas to 9 or 10 ft will
prevail in the south-central Caribbean Sea through the forecast
period. Tropical waves will continue to move across the basin,
elsewhere, producing some convective precipitation and little
impact in winds and seas. It is possible that the wind speeds and
the sea heights may be higher near thunderstorms.
ATLANTIC OCEAN...
The southernmost part of a stationary front passes through 33N77W
to 31N81W near the coast of SE Georgia. A narrow NE-to-SW oriented
upper level trough extends from 32N81W near the South
Carolina/Georgia border, across NE Florida, to 28N83W in the NE
corner of the Gulf of Mexico, to 23N88W in the Gulf of Mexico. An
upper level cyclonic circulation center is near 23N75W, on top of
the central Bahamas. A second cyclonic circulation center is near
29N67W. Widely scattered moderate to isolated strong rainshowers
are to the west of the line that passes through 33N70W 27N75W
22N76W. Isolated moderate rainshowers are elsewhere from 70W
westward. Isolated moderate rainshowers are in the Gulf of Mexico
from 94W eastward.
An upper level trough extends from a 34N18W cyclonic circulation
center, to 34N35W, to a second cyclonic circulation center that is
near 29N46W. The trough continues to a third cyclonic circulation
center that is near 23N62W, into the NE corner of the Caribbean
Sea near 18N63W and 16N70W. Isolated moderate rainshowers are
within 300 nm on either side of the trough from 27N northward
between 40W and 55W, and elsewhere from 20N northward between 50W
and 72W. A surface trough is along 27N67W 24N70W 20N72W to the
north of Hispaniola and at the SE end of the Bahamas.
A surface trough, that is near the SE Bahamas, is forecast to
move across the area through Monday. Gentle to moderate winds
will be associated with this trough. Winds will pulse to fresh to
strong during the evening and nighttime hours just N of
Hispaniola through the middle of next week. A surface ridge will
dominate the rest of the forecast area, supporting a gentle to
moderate anticyclonic flow.
For additional information please visit
http://www.hurricanes.gov/marine
$$
MT
https://www.nhc.noaa.gov/
------------------------------------------------------------------
The tropical Atlantic remains quiet!... RTW
