351
AXNT20 KNHC 161720
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Sun Jun 16 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...

Heavy Rainfall over Central America and Mexico:

A broad area of low pressure is centered over northern Central
America and southern Mexico. This weather pattern is known as a
Central American Gyre (CAG), and often persists for several days
resulting in life-threatening conditions that include flooding
and mudslides. With the current CAG, the circulation is producing
strong SW monsoonal flow in the eastern north Pacific that will
advect abundant tropical moisture northward into the coastal
terrain of Central America and southern Mexico. The pattern is
expected to persist through at least the middle of this week
across northern Central America and southern Mexico, with the
threat to life and property increasing as the event persists. The
main areas impacted by the heavy rainfall will be northwest
Nicaragua, southwest Honduras, and coastal sections of Honduras,
El Salvador, Guatemala, and the Mexican states of Chiapas and
Oaxaca. Heavy rainfall is also possible across Quintana Roo,
Yucatan, Tabasco, Veracruz, NE Queretaro, NE Hidalgo, and San
Luis Potosi this week.

The persistence of the moist pattern will create very hazardous
conditions in the region that could be life-threatening. Please
refer to your local meteorological office bulletins for more
detailed information.

...TROPICAL WAVES...

The axis of an eastern Atlantic tropical wave is near 24W, from
15N southward, moving westward around 10-15 kt. Convection is
limited near the wave axis.

The axis of a central Atlantic tropical wave is analyzed near
55W/56W, extending from 16N southward. It is moving west at 10-15
kt. Scattered moderate convection is from 09N to 14N between 52W
and 58W.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic through the coast of Guinea
Bissau near 12N16W, then continues westward to 08N27W. The ITCZ
extends from 08N27W to 05N40W to the coast of Suriname near 06N55W.
Scattered moderate convection is noted from 05N to 09N E of 16W to
the coast of W Africa, and from 03N to 09N between 29W and 55W.

GULF OF MEXICO...

Please read the SPECIAL FEATURES section for information on the
possibility of heavy rainfall across the Yucatan Peninsula,
Tabasco, Veracruz, and parts of Queretaro, Hidalgo, and San Luis
Potosi this week.

A Central American Gyre is currently over southern Mexico and
Central America. A surface trough extends over the SW Gulf and
runs from 24N96W to a 1005 mb low pressure located near northern
Guatemala/Mexico border. The pressure gradient between a ridge
across the eastern Gulf and the low supports moderate to fresh
winds S of 25N and E of 92W, with gentle to moderate winds
elsewhere. Seas are in the 4-6 ft range E of 90W, and 2-4 ft W of
90W. Showers and thunderstorms are flared-up over the north-
central and NE Gulf.

For the forecast, the gyre center is expected to persist through
the middle of this week, while shifting WNW to NW into the SW Gulf
of Mexico. Environmental conditions appear conducive for a
tropical cyclone to develop from this broad area of low pressure,
and a tropical depression could form could form by midweek while
it moves slowly westward or west-northwestward. Regardless of
development, several days of heavy rainfall are expected across
portions of southern Mexico and Central America. These rains are
likely to cause life-threatening flooding and flash flooding. Active
convection across the southeast Gulf, along with increasing winds
to gale-force and rough seas, is expected to shift westward with
this system Mon through the middle part of the week, impacting
the south-central and northwest Gulf.

CARIBBEAN SEA...

Please read the SPECIAL FEATURES section for information on the
potential for heavy rainfall across the Yucatan Peninsula this
week.

A Central American Gyre is currently over southern Mexico and
Central America. The circulation around the gyre is supporting
fresh to strong SE winds over the NW Caribbean. Moderate to fresh
winds are noted elsewhere. Seas are in the 6-8 ft range over the
NW Caribbean, and 4-6 ft elsewhere except the far NE Caribbean
where seas are in the 3-4 ft range. Under the SE flow, band of
showers with embedded thunderstorms are noted over the NW
Caribbean, particularly from 15N to 20N between 80W and 85W.
Scattered showers and thunderstorms are also noted over the SW
Caribbean in a S to SW wind flow.

For the forecast, the gyre center is expected to persist through
the middle of this week, while shifting WNW to NW into the Gulf of
Mexico. The resultant pattern will produce fresh to near gale-
force SE winds and scattered showers and thunderstorms across
portions of the western and northwestern Caribbean today, then
shift across the NW Caribbean and Gulf of Mexico tonight through
Wed. Otherwise, gentle to moderate trades over the central and E
Caribbean will reach moderate to fresh speeds on Wed and prevail
through Thu night.

ATLANTIC OCEAN...

A surface trough extends from 31N60W to a weak 1015 mb low
pressure located near 26N67W, then continues SW to near the
easternmost tip of Cuba. Scattered showers and thunderstorms are
N of 27N and ahead of the trough to about 55W. Another trough is
analyzed farther NW and stretches from 31N68W to near Cape
Canaveral, Florida. Scattered showers and thunderstorms persist N
of 27N and east of the trough to about 65W. Satellite derived wind
data confirmed the presence of these trough, with light to gentle
winds on either side of them. To the east of 55W, high pressure
prevails, with a 1026 mb center near 34N38W. Light to gentle
winds generally dominate the waters W of 55W, with seas in the 2-4
ft range. Elsewhere, moderate to fresh winds are noted, with seas
in the 4-7 ft range.

For the forecast west of 55W, the above mentioned troughs are
forecast to merge while shifting eastward with active convection
continuing ahead of them. High pressure will build over the
western Atlantic in the wake of the trough. An area of low
pressure is forecast to form along the trough axis by midweek a
few hundred miles northeast of the central Bahamas. Environmental
conditions could be conducive for some development of this system
thereafter while it moves westward or west-northwestward. The
pressure gradient between the high pressure to the N and the
developing low will support an area of fresh to strong easterly
winds north of 26N and west of 65W by Tue. This area of winds
will shift westward in tandem with the low.

$$
GR