AXNT20 KNHC 251753
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
152 PM EDT Sun Aug 25 2019
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
The center of Tropical Storm DORIAN, at 25/1500 UTC, is near
11.2N 52.9W. DORIAN is moving W, or 280 degrees, 12 knots. The
estimated minimum central pressure is 1008 mb. The maximum
sustained wind speeds are 35 knots with gusts to 45 knots. Widely
scattered to scattered moderate and isolated strong rainshowers
are within 200 nm of the center in the NW semicircle. The Public
Advisories about Tropical Storm DORIAN are issued under WMO
header WTNT35 KNHC and under AWIPS header MIATCPAT5. The
Forecast/Advisories about Tropical Storm DORIAN are issued under
WMO header WTNT25 KNHC and under AWIPS header MIATCMAT5.
A surface trough extends from 32N75W in the Atlantic Ocean, to a
1011 mb low pressure center that is near 31N77W. The trough
continues to Florida, just to the E of Lake Okeechobee, and to
24N83W in the SE Gulf of Mexico. Scattered moderate to strong
rainshowers are within 240 nm to the east of the trough from 25N
northward, within 60 nm on either side of the trough from 24N to
26N in Florida and along the SW coast of Florida. Isolated
moderate rainshowers are elsewhere from 24N northward from 86W
eastward. Environmental conditions appear to be conducive for
gradual development. It is likely that a tropical or subtropical
depression may form within the next few days, while the system
moves slowly northeastward well offshore of the southeastern
United States. Interests along the coasts of South Carolina and
North Carolina should continue to monitor the progress of this
system. The Air Force Reserve Hurricane Hunter aircraft mission
that was scheduled for this afternoon was canceled. Another
aircraft is scheduled to investigate the system on Monday, if
necessary. The chance of development into a tropical cyclone
through 48 hours is high.
An Atlantic Ocean tropical wave is along 31W, S of 21N, moving W
10 knots. Rainshowers are possible from 10N to 26N between Africa
A Caribbean Sea tropical wave is along 68W/69W, S of 20N, moving
W 15 to 20 knots. Isolated moderate rainshowers are within 180 nm
to the west of the wave, from 16N to central sections of
A Caribbean Sea tropical wave is along 84W/85W, S of 22N, moving
W 10 to 15 knots. The wave extends from the NW tip of Cuba,
through Honduras, Nicaragua, and Costa Rica. Isolated moderate
rainshowers are from 17N northward from Jamaica westward. The GFS
model for 250 mb, for 500 mb, and for 700 mb, shows an upper
level inverted trough in the western Caribbean Sea near the wave.
The monsoon trough passes through the coastal sections of
Mauritania near 18N16W, to 16N23W near the Cabo Verde Islands, to
12N33W and 12N37W. The ITCZ continues from 12N37W to 12N47W.
Widely scattered moderate to isolated strong rainshowers are from
04N to 15N from 20W eastward, from 06N to 10N between 27W and 40W,
and from 09N to 11N between 40W and 45W. Isolated moderate
rainshowers are elsewhere, from 12N southward, away from T.S.
DORIAN, from 60W eastward.
GULF OF MEXICO...
Broad upper level anticyclonic wind flow spans the Gulf of Mexico.
The GFS model for 500 mb and for 700 mb shows a trough in the
NW corner of the Gulf of Mexico. Scattered to numerous strong
rainshowers are from 27N northward from 91W westward, in the
coastal waters of Louisiana and Texas. Widely scattered moderate
to isolated strong rainshowers also are from 25N to 28N between
93W and 96W, about 180 nm off the coasts of Texas and NE Mexico.
Relatively weak high pressure will remain in the area through
Thursday night. The high pressure will maintain moderate to fresh
south to southeast winds in the waters west of 90W. Winds will be
mainly light to gentle east of 90W through the period. Upper level
disturbances will keep unsettled weather conditions in much of
the NW and north central Gulf of Mexico through Monday night.
The GFS model for 250 mb, for 500 mb, and for 700 mb shows an
upper level inverted trough, either in the NW corner of the
Caribbean Sea or across the Yucatan Peninsula of Mexico.
Isolated moderate rainshowers are in the NW part of the Caribbean
The monsoon trough is along 09N between 74W in Colombia and 84W
just off the coast of Costa Rica in the eastern Pacific Ocean.
Scattered to numerous strong rainshowers are in the coastal
plains, and within 90 nm of the coast from 08N to 13N between 80W
and 85W, from Panama to Nicaragua. Warming cloud top temperatures,
and weakening but possibly still lingering precipitation, are
within 120 nm to the north of the monsoon trough between northern
Colombia and 80W. Widely scattered moderate to isolated strong
rainshowers are in northern Colombia from the monsoon trough to
Fresh to strong trade winds in the south central Caribbean Sea
will increase gradually in areal coverage through Monday. Fresh
to strong east to southeast winds will pulse in the Gulf of
Honduras at night from Monday through Wednesday. Tropical Storm
Dorian near 11.2N 52.9W 1008 mb at 11 AM EDT moving W 12 kt.
Maximum sustained winds 35 kt gusts 45 kt. Dorian will move to
11.5N 54.6W this evening and to 12.0N 56.9W Mon morning with
maximum sustained winds 45 kt gusts 55 kt. Dorian will continue
to strengthen gradually, as it moves to 12.7N 59.1W Mon evening,
with maximum sustained winds 50 kt gusts 60 kt, then cross into
the eastern Caribbean Sea near 13.5N 61.2W Tue morning with
maximum sustained winds 55 kt gusts to 65 kt and reach hurricane
strength near 15.6N 65.3W with maximum sustained winds 65 kt gusts
80 kt by early Wed, before it weakens to a tropical storm near
17.5N 69.0W early on Thu with maximum sustained winds 60 kt gusts
One upper level cyclonic circulation center is near 30N63W. A
surface trough is along 31N56W 27N57W 25N59W. Widely scattered
moderate to isolated strong rainshowers are within 180 nm to the
east of the trough, and within 120 nm to the west of the trough.
Other isolated moderate rainshowers are within 180 nm on either
side of the line that runs from 32N50W 27N56W 23N66W.
Low pressure near 31N77W 1011 mb will continue to track
northeastward, to north of the area near 33N73W 1009 mb by early
Monday. A trough will trail from the low, to near West Palm Beach.
Unsettled weather, scattered to numerous rainshowers and
thunderstorms, some with strong gusty winds and rough seas, is
expected in the waters that are between 72W and 80W during the
next couple of days. Environmental conditions appear conducive for
gradual development of the low pressure system. A tropical or
subtropical depression is likely to form within the next few days,
as the low tracks to the NE north of the area. Gentle to moderate
southeasterly winds will continue elsewhere across the area.
Tropical Storm Dorian, currently in the tropical Atlantic Ocean,
is forecast to move across the eastern Caribbean Sea as a
hurricane by the middle of the week, and near the far southeastern
waters as a tropical storm by late in the week. Expect increasing
winds and building seas in those waters with the approach of