673
AXNT20 KNHC 131031
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Thu Jun 13 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 0600 UTC surface analysis and satellite imagery through
1015 UTC.

...SPECIAL FEATURES...

Heavy Rainfall over the southeastern Gulf of Mexico, portions of
the Florida Peninsula, and the western Atlantic: Abundant
tropical moisture is surging northward from the western Caribbean,
across the southeastern Gulf of Mexico, also over portions of
Florida, and across the adjacent western Atlantic waters. This
moisture resides to the southeast of a surface trough that
extends from near 31N78W southwestward to east-central Florida
just north of Cape Canaveral to an elongated area of low pressure
(Invest AL90) with a mean position just offshore Port Canaveral
with a pressure of 1010 mb. A surface trough continues from this
elongated area of low pressure southwestward to near Sarasota,
Florida to 25N86W and to the northern Yucatan Peninsula. Also,
upper-level diffluent flow present across the region. As a result,
numerous showers and scattered thunderstorms are present
southeast of the trough over the western Atlantic from 25N to 31N
between 70W and 76W and south of 26N west of 76W including the
Straits of Florida, the majority of the Florida Key, over central
Cuba and its adjacent waters. In addition numerous thunderstorms
are quickly developing over the Yucatan Peninsula extending north
to near 24N between 87W and 90W. Cloud to surface lightning,
strong gusty winds, rough seas and low visibility are ongoing
within this convective activity over these areas. The shower and
thunderstorm activity is expected to continue across the region
through Fri. Mariners transiting these regions should exercise
caution. Please refer to bulletins and forecasts from your local
weather forecast offices for specific local information.

...TROPICAL WAVES...

A far eastern Atlantic tropical wave has its axis along 29W from
03N to 14N. It is moving westward near 15 kt. The moisture
associated with this wave is vividly depicted in the CIMSS Total
Precipitable Water (TPW) satellite animation. Scattered showers
are near the northern part of this wave.

A central Atlantic tropical wave has its axis along 41W from 02N
to 15N, moving westward at about 15 kt. No significant convection
is presently noted with this wave as it is moving through a stable
surrounding environment that consists of the Saharan Air Layer.
However, a pocket of scattered showers and thunderstorms is seen
moving westward to the southwest of the wave south of 02N between
41W and 45W.

A central Caribbean tropical wave has its axis along 73W south of
13N to well inland Colombia. It is moving near 10 kt. Small
isolated showers are near the wave axis from 05N to 09N.

A western Caribbean tropical wave has its axis along 81W south of
15N, moving westward at 10 kt. Related scattered moderate to
isolated strong convection is over the eastern Pacific near the
coast of Panama.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from the coastal plains of the
southwest part of Senegal to 10N26W. Overnight scatterometer data
indicates that the ITCZ begins at 09N29W and continues to near
07N40W. Numerous moderate to strong convection emerging off
West Africa is from 05N to 10N between the coast and about 19W.
This convection is most likely in advance of the next tropical
wave.

...GULF OF MEXICO...

Please read the Special Features section for information about
heavy rainfall over the southeastern Gulf of Mexico.

A stationary front extends from northeast Florida to just south
of Louisiana, and westward from there to inland Texas near
Houston/Galveston area. Elsewhere, as described above, a surface
trough extends from near Sarasota, Florida to 25N86W and to the
northern Yucatan Peninsula. Numerous thunderstorms are quickly
developing over the Yucatan Peninsula and reach northward to
near 24N between 87W and 90W. Overnight ASCAT satellite data
passes revealed light to gentle generally variable winds west of
the trough, with moderate to fresh south to southwest winds east
of the trough, locally higher in any convection. Seas are 1 to 3
ft west of the trough, and 3 to 4 ft east of the trough, except to
5 ft near the Yucatan Channel due to a southeast swell. Hazy
conditions are over the SW Gulf due to ongoing agricultural fires
are in Mexico.

For the forecast, the aforementioned trough is expected to
gradually weaken through late Fri while the low pressure moves
northeastward to offshore of the southeastern U.S. Looking ahead,
a broad area of low pressure is forecast to form over the
southwestern Gulf of Mexico this weekend. Environmental conditions
appear conducive for gradual development of this system and a
tropical depression could form during the early or middle part
of next week while it moves slowly westward or west-
northwestward. Increasing winds and building seas are expected
with this system.

...CARIBBEAN SEA...

The pressure gradient between Atlantic high pressure, lower
pressures in the deep tropics, and the trough of low pressure
across the southeastern Gulf of Mexico is resulting in moderate to
fresh east to southeast winds over most of the basin, with the
exception of the central basin, where winds are fresh to strong,
including between Cuba and Jamaica. Seas range from 7 to 9 ft
over the central Caribbean and 4 to 6 ft elsewhere, except 3 to 5
ft east of 65W and also over the southwestern Caribbean.

The eastern segment of the E Pacific monsoon trough stretches
from Central America southeastward to 11N80W and to northwest
Colombia. Scattered showers and isolated thunderstorms are between
northwest Colombia and southern Panama.

For the forecast, high pressure located NE of the area combined
with the Colombian low and the passage of tropical waves will
support fresh to strong trade winds across the central Caribbean
through tonight. Moderate to fresh southeast winds are expected
over the northwestern Caribbean likely through Fri as a trough of
low pressure remains over the eastern Gulf of Mexico. Otherwise,
scattered showers and thunderstorms are forecast to continue
across portions of the northwestern Caribbean through the rest of
the week as a surge of tropical moisture persists across the
region. Looking ahead, expect increasing winds and building seas
over the western Caribbean, including the Gulf of Honduras, over
the upcoming weekend as a broad area of low pressure is forecast
to form over the southwestern Gulf of Mexico.

...ATLANTIC OCEAN...

Please read the Special Features section above for more
information about the heavy rainfall over the western Atlantic
and near and over portions of the Florida peninsula.

A stationary front extends from low pressure of 1015 mb that is
well north of the area near 34N71W southwestward to near
Jacksonville, Florida. Deep convection over the western Atlantic
is described above. Fresh to locally strong winds and 5 to 7 ft
seas are within 180-240 nm southeast of the front. A surface
trough supported by an upper-level is analyzed from near 30N42W
to 23N47W and to 15N53W. The upper-level low is identified on
satellite water vapor imagery to be near 27.5N47W. Broken to
overcast mostly mid-level clouds with embedded increasing
scattered showers and thunderstorms are seen from 22N to 30N
between 41W and 46W. A weak trough extends from 31N59W to 26N58W
and to 20N56W. An overnight ASCAT satellite pass nicely captured
the northeast to southeast wind shift across the trough axis.
These winds consist of gentle to moderate speeds. Scattered
showers and isolated thunderstorms are seen from 20N to 24N
between 50W and 57W.

Other than the features above, strong high pressure of 1032 mb
located well north of the discussion area in the vicinity of the
Azores has an associated ridge that reaches southwestward to the
central Bahamas, disrupted by the troughs. Mainly gentle to
moderate winds and seas of 3 to 6 ft seas dominate the basin west
of 35W, and also south of 14N and east of 35W. Moderate to fresh
trade winds are north of 14N and east of 35W, except for fresh to
strong northeast winds that are present generally from the Cabo
Verde Islands to the Canary Islands, including along the coast of
Africa. Seas are 5 to 7 ft across this area. Saharan Air dominates
the lower to middle atmosphere across the Atlantic from about 10N
to 20N and roughly between Africa and the Lesser Antilles.

For the forecast west of 55W, some gradual development is possible
with the elongated area of low pressure near the east coast of
Florida, and that has an associated 1010 mb low just offshore
Port Canaveral as discussed above under the Special Features
section during the next couple of days, despite strong upper-
level winds, while the system moves northeastward offshore of the
southeastern U.S. coast. The deep convection related to this
feature will be numerous in coverage and contain gusty winds and
frequent lightning at times over most of the western part of the
forecast waters, mainly west of a line from 31N68W to 26N71W to
central Cuba. Expect for little change with this convective
activity through at least Fri. Fresh to strong southerly winds are
expected over the western Atlantic ahead of this system during
the next couple of days. High pressure will build southward over
the western Atlantic beginning this weekend and into early next
week.

$$
Aguirre