000
AXNT20 KNHC 131112
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
711 AM EDT Fri Sep 13 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 0600 UTC surface analysis and satellite imagery through
1050 UTC.

...SPECIAL FEATURES...

The center of Potential Tropical Cyclone Nine, at 13/0900 UTC, is
near 24.6N 75.2W. This position also is about 221 nm/410 km to
the ESE of Freeport in Grand Bahama Island, and about 148 nm/275
km to the SE of Great Abaco Island, in the Bahamas. The feature
is moving NW, or 310 degrees, 5 knots. The estimated minimum
central pressure is 1009 mb. The maximum sustained wind speeds are
25 knots with gusts to 35 knots. Scattered strong rainshowers are
within 240 nm of the center in the E quadrant. Widely scattered
moderate to isolated strong rainshowers are elsewhere within 300
nm to 500 nm of the center in the E quadrant. The system is
anticipated to move across the central and northwestern Bahamas
today, and along or over the east coast of Florida on Saturday
and Saturday night. The disturbance is forecast to become a
tropical depression, or a tropical storm, during the next day or
so. The chance of tropical cyclone formation during the next 48
hours is high. Please, read the latest NHC forecast/advisory under
AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC, or go to the website
hurricanes.gov, for more details.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave is along 35W/36W, from 20N
southward, moving W 10 to 15 knots. Widely scattered to scattered
moderate and isolated strong rainshowers are between this tropical
wave, and the tropical wave that is along 44W/45W. The
atmospheric conditions are expected to become more conducive for
development in a couple days. It is possible that a tropical
depression may form early next week, while the system moves
quickly westward across the tropical Atlantic Ocean.

An Atlantic Ocean tropical wave is along 44W/45W, from 20N
southward, moving W 10 to 15 knots. Widely scattered to scattered
moderate and isolated strong rainshowers are between this tropical
wave, and the tropical wave that is along 35W/36W. Isolated
moderate rainshowers are elsewhere within 240 nm to the west of
this tropical wave, from 06N to 14N.

An Atlantic Ocean tropical wave is along 57W/58W, from 20N
southward, moving W 10 knots. Widely scattered moderate to
isolated strong rainshowers are within 400 nm to the east of the
wave from 14N to 17N, and within 210 nm to the west of the wave,
from 13N to 16N.

A Caribbean Sea tropical wave is along 80W/81W, from 19N
southward, moving W 15 knots. Numerous strong rainshowers are
within 120 nm to the east of the wave, and within 75 nm to the
west of the wave, from Panama to 11N. The precipitation also is
near the monsoon trough, in the SW corner of the Caribbean Sea.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through SW Senegal near 13N17W to
10N27W, to 08N39W, and to 08N48W. Widely scattered moderate to
isolated strong rainshowers are within 240 nm to the south of the
monsoon trough between 24W and 37W, and within 90 nm to the north
of the monsoon trough between 26W and 29W. Isolated moderate
rainshowers are from 04N to the monsoon trough from 24W eastward,
and elsewhere within 210 nm to the south of the monsoon trough
between 37W and 50W.

GULF OF MEXICO...

An upper level cyclonic circulation center is in the east central
Gulf of Mexico. Upper level cyclonic wind flow covers at least the
northern half of the Gulf of Mexico. Widely scattered moderate to
isolated strong rainshowers are from 24N northward from 90W
eastward. Widely scattered moderate rainshowers are elsewhere E of
90W.

An upper level cyclonic circulation center is in interior southern
Mexico. Isolated moderate rainshowers are in the SW corner of the
Gulf of Mexico, from 24N southward from 94W westward. Isolated
moderate rainshowers are elsewhere from 25N southward from 90W
westward.

High pressure over the southeastern United States
will support moderate to fresh northeast to east winds into the
weekend. Potential Tropical Cyclone Nine currently over the
central Bahamas will track northwestward off the east coast of
Florida through early next week. The gradient between the
cyclone and the high pressure will allow for fresh winds over
the NE Gulf Fri night into Sat along with building seas.
Scattered showers and thunderstorms may spread westward from the
Florida peninsula to the eastern Gulf through Sun.

CARIBBEAN SEA...

Isolated moderate rainshowers are in the area that is to the NW
and W of the line that runs from 80W in Cuba to eastern Honduras.
Part of the precipitation that is in the NW corner is related to
the east central Gulf of Mexico upper level cyclonic circulation
center. Another part of the precipitation is related to the
cyclonic wind flow that is moving around Potential Tropical
Cyclone Nine.

The monsoon trough is along 07N/08N between 74W in northern
Colombia, westward, beyond southern Panama, into the eastern
Pacific Ocean. Numerous strong rainshowers are from Panama to 11N
between 78W and 82W.

High pressure north of the area will maintain
moderate trades, that will at times pulse to fresh to strong in
the south central Caribbean. A tropical wave will cross from the
central Caribbean into the western Caribbean today, then exit
into Central America Sun. Another tropical wave will enter the
tropical N Atlantic and eastern Caribbean tonight. A third and
stronger tropical wave will approach the tropical N Atlantic and
eastern Caribbean over the weekend into early next week, expected
to bring widespread showers and thunderstorms, gusty winds and
building seas.

ATLANTIC OCEAN...

Upper level cyclonic wind flow covers the area that is from 21N
northward between 50W and 64W. A surface trough is along 32N50W
28N52W. Scattered moderate to isolated strong rainshowers are
from 27N to 36N between 46W and 52W. Isolated moderate rainshowers
are from 20N to 30N between 53W and 63W.

Potential Tropical Cyclone Nine is over the central
Bahamas near 24.6N 75.2W 1009 mb at 5 AM EDT, moving NW at 5 kt.
Maximum sustained winds are 25 kt with gusts to 35 kt. Nine will
move to 25.1N 76.2W this afternoon, impacting Grand Bahama
possibly as a tropical storm near 26.0N 77.8W Sat morning, before
move northward to 27.0N 79.3W Sat afternoon, 28.2N 80.4W Sun
morning, and 30.3N 81.1W Mon morning. Nine will change little in
intensity as it moves north of the area off the coast of Georgia
early Tue, then move eastward into the open Atlantic through Wed.
Elsewhere, a tropical wave may approach the waters south of 22N
early next week.

$$
MT