683
AXNT20 KNHC 201710
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Fri Sep 20 2024

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 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1700 UTC.

...SPECIAL FEATURES...

Potential Heavy Rainfall in Central America: Recent satellite
imagery shows numerous moderate to strong thunderstorms,
associated with a developing Central American Gyre (CAG), over
the far southwest Caribbean impacting inland portions of Honduras,
Nicaragua, Costa Rica, Panama, and Colombia. This thunderstorm
and heavy rainfall activity is expected to persist through this
weekend and into the middle of next week while moving
northwestward, becoming focused in El Salvador, Guatemala, and
southern Mexico by late next week. The heaviest rainfall is
expected along the south and west coasts of Mexico, Guatemala, El
Salvador, Nicaragua, and Costa Rica. Heavy rainfall will lead to
increased potential for life-threatening flash flooding and
mudslides in these areas. It is recommended that residents in the
aforementioned areas stay alert on the latest information from
their meteorological agencies. Please refer to the Tropical
Weather Discussion for the Eastern Pacific at website:
https://www.hurricanes.gov/text/MIATWDEP.shtml for more details on
rainfall across the Pacific coastal areas of these nations.

...TROPICAL WAVES...

A western Caribbean tropical wave has its axis near 88W, from 20N
southward along the Yucatan coast and in the western Gulf of
Honduras, then extending S across Central America. It is moving W
at 10 kt. Scattered moderate convection is observed near the
northern portion of the wave axis, generally from 16N to 20N
between 81W and the wave axis.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the basin from the west coast of Africa
near 11N16W and continues westward to near 07N38W. The ITCZ then
stretches from 07N38W to near 09N45W. Scattered moderate
convection is seen south of these features between the African
coast and 40W, and north of 04N.

The East Pacific monsoon trough also extends across the southwest
Caribbean to inland Colombia. Convection in this area is
associated with a developing Central American Gyre, see the
SPECIAL FEATURES section above for more details.

...GULF OF MEXICO...

A diurnal surface trough is analyzed from the Bay of Campeche to
just north of the Yucatan Peninsula, with scattered showers
developing along and near the northern portion of the trough axis.
Another surface trough is noted over the NE Gulf with no notable
convection nearby. Otherwise, high pressure of 1012 mb centered
near 28N93W is dominating Gulf weather, bringing dry conditions,
light to gentle winds, and seas of less than 3 ft.

For the forecast, moderate to locally fresh winds may pulse in
the eastern Bay of Campeche nightly through the next several days.
Looking ahead, a broad area of low pressure could form by the
early to middle part of next week over the northwestern Caribbean
Sea. Thereafter, gradual development of this system is possible,
and a tropical depression could form as the system moves slowly to
the north or northwest over the northwestern Caribbean Sea and
into the southern Gulf of Mexico through the end of next week.
There is a medium chance of tropical cyclone formation in the next
seven days. Regardless of development, winds and seas will start
increasing across the SE Gulf early next week.

...CARIBBEAN SEA...

Please refer to the SPECIAL FEATURES section above for details on
convection in the southwest Caribbean associated with a developing
Central American Gyre (CAG).

Convergent surface winds are leading to the development of
scattered showers and isolated thunderstorms in the far eastern
Caribbean. Otherwise, moderate to locally fresh easterly winds
and seas at 3 to 5 ft are evident in the central basin. Gentle to
moderate SE to E winds and 2 to 4 ft seas are seen across the
remainder of the basin.

For the forecast, moderate to fresh winds and moderate seas are
expected across the E and central Caribbean through at least Sat.
Looking ahead, a broad area of low pressure could form by the
early to middle part of next week over the northwestern Caribbean
Sea. Thereafter, gradual development of this system is possible,
and a tropical depression could form as the system moves slowly to
the north or northwest over the northwestern Caribbean Sea and
into the southern Gulf of Mexico through the end of next week.
There is a medium chance of tropical cyclone formation in the next
seven days.

...ATLANTIC OCEAN...

A surface trough that extends roughly along the Gulf Stream
offshore Florida is inducing scattered moderate convection in its
immediate vicinity. An upper-level trough is also helping to
generate areas of scattered moderate convection over and to the
northeast of the Bahamas and the Turks and Caicos Islands. A 1006
mb area of low pressure centered near 25N55W and a surface trough
extending both to the west and east of the low are generating
scattered moderate convection along and within 200 nm of the
trough axis. To the north of these features, recent scatterometer
data indicated moderate to fresh E winds generally north of 26N
between 50W and 59W, along with seas of 7 to 10 ft in this area.
Environmental conditions appear marginally conducive for some
tropical development of this system while it meanders in the
Subtropical Atlantic through early next week, and there is a low
chance of tropical formation over the next 7 days.

To the east, another low pressure of 1007 mb, is associated with
the remnants of Gordon. This low is centered near 27N43W. Convection
associated with this low is mainly displaced E of the center, N
of 24N between 30W and 41W. In and near this zone of scattered
moderate convection, fresh to locally strong E winds and seas of 7
to 10 ft prevail. Some development of these remnants is possible
over the next day or two as the low moves N or NNE. Thereafter,
conditions are forecast to be less conducive for development.
Elsewhere, light to gentle winds and seas at 4 to 7 ft dominate
most of the basin.

For the forecast W of 55W, an area of low pressure is centered
near 25N55W. Fresh to strong winds and rough seas will impact the
waters N of 25N and E of 60W today in association with this low.
Environmental conditions appear marginally conducive for some
tropical development of this system while it meanders in the
Subtropical Atlantic through early next week. Otherwise, a weak
cold front will move off the SE coast of the US today and slowly
move across the waters N of 25N through Mon.

$$
Adams