582 
AXNT20 KNHC 092319
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Sat Jun 10 2023

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 1800 UTC surface analysis and satellite imagery through
2300 UTC.

...SPECIAL FEATURES...

Excessive Rainfall in Eastern and Central Cuba and the Central 
Bahamas: An upper level trough located over the eastern Gulf of
Mexico with SW flow extending down to the surface is transporting
a large amount of moisture northward from the deep tropics, 
creating an atmospheric river over Cuba and the Central Bahamas. 
Over the past 24 hours, Las Mercedes in Granma, Cuba reported 14 
inches (360 mm) of rainfall. Additional reports show 24 hour 
rainfall amounts ranging from 8-12 inches (200-300 mm) elsewhere 
in Granma, Santiago de Cuba, and Camaguey where life-threatening 
flooding has been reported. In the Bahamas, 8 inches (200 mm) was
reported on Exuma and 4 inches (100 mm) was reported on Long 
Island over the past 24 hours. Persistent convection in eastern 
and central Cuba and the central Bahamas is forecast to produce 
another 4-6 inches (100-150 mm) of rainfall over the next 24 
hours. Heavy rainfall may cause flooding and mudslides, 
especially in the mountainous areas of eastern and central Cuba. 
Conditions are forecast to improve late Sat. Please refer to the 
latest forecast from your national meteorological service for 
more information.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave is along 19W from 11N southward,
moving W at 10-15 kt. A few showers are near the wave axis. 

An Atlantic Ocean tropical wave is along 41W from 12N southward,
moving W from 10-15 kt. Some shower activity is noted near the
wave axis.  

A Caribbean Sea tropical wave extends from the Windward Islands
across eastern Venezuela. Its axis is along 61W/62W. The wave
appears to enhance convection over eastern Venezuela. 

Another tropical wave is along 80W extending southward into the 
eastern Pacific region. Scattered moderate convection is near the
northern end of the wave axis.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coast of Guinea near 10N14W
then continues SW to near 06N21W. The ITCZ extends from 06N21W 
to 07N35W to the coast of Suriname near 06N56W. Scattered moderate
convection is from 03N to 05N between 11W and 32W, and from 08N 
to 11N between 38W and 56W. 

GULF OF MEXICO...

A weak pressure pattern continues to dominate the Gulf waters 
supporting mainly light to gentle winds and slight seas. A 1012 
mb high pressure remains over the western Gulf near 25N92W. A
stationary front is over N Florida generating showers and
thunderstorms. Scattered showers and thunderstorms are noted 
over the central Gulf, particularly from 24N to 28N between 87W
and 90W. A mid-upper level trough remains over the eastern Gulf,
and continues to enhance convection over Florida and western 
Cuba.

For the forecast, a weak pressure gradient will generally prevail
across the basin through Sat morning with light to gentle winds.
As weak low pressure is forecast to develop along a frontal 
boundary over Texas on Sat. As a result, moderate to locally fresh
return flow will prevail over the western Gulf Sat night through
Sun morning, and again Mon night into Tue. By the middle of next
week, the area of fresh southerly winds could expand over the 
eastern Gulf.

CARIBBEAN SEA...

Please read the SPECIAL FEATURES section for information on
EXCESSIVE RAINFALL for Eastern and Central Cuba.

Moderate to fresh trades prevail in the eastern and central Caribbean,
with an area of fresh to locally strong E to SE winds just off 
Haiti to about 15N. Seas are 6-8 ft per altimeter data within 
these winds, and 4-6 ft elsewhere across the east and central 
Caribbean. Light to gentle winds are noted over the NW part of
the basin with seas of 2-4 ft. Numerous showers and thunderstorms  
producing excessive rainfall over Cuba are also noted between
Jamaica and the Cayman Islands, and over the Jardines de la Reina
Keys. Convection has flared-up over parts of Central America,
more concentrated over Honduras, Nicaragua and NW of Costa Rica.

For the forecast, high pressure over the central Atlantic extends
a ridge across the northern Caribbean. The pressure gradient 
will maintain moderate to fresh E to SE trade winds across the 
eastern and central Caribbean through the weekend. Easterly trade
winds will increase to fresh to strong across the central Caribbean
and Gulf of Honduras early next week. Enhanced thunderstorms will
continue between eastern Cuba and Jamaica through Sat morning, 
due to the presence of an upper-level trough just NW of the area.

ATLANTIC OCEAN...

Please read the SPECIAL FEATURES section for information on
EXCESSIVE RAINFALL in the Central Bahamas.

High pressure of 1021 mb located over the central Atlantic near
27N49W extends a ridge westward across the Greater Antilles, the
Bahamas and the western Atlantic. Multilayer clouds, with 
embedded showers and thunderstorms dominate most of the waters W 
of 70W. This cloudiness is associated with strong upper-level 
SW winds. Moderate to fresh southerly winds are noted on the 
western periphery of the ridge, with seas of 4-6 ft E of the 
Bahamas. Winds and seas could be higher near thunderstorms. A 
weakening cold front enters the forecast waters near 31N30W and 
extends SW to near 28N34W. A surface trough is analyzed from this
point 24N41W. mainly low clouds with possible showers are 
related to the front/trough. A weak pressure gradient dominates 
the eastern Atlantic under the influence of a 1017 mb high 
pressure located W of the Canary ISlands near 27N21W. Mainly 
light to gentle winds are observed across the Atlantic E of 50W 
with seas generally in the 3-5 ft range. Moderate to locally 
fresh trades are E of the Lesser Antilles to 50W with seas of 4-5
ft. 

For the forecast west of 55W, high pressure extending from the 
central Atlantic is creating a tight pressure gradient with low 
pressure off the SE US coast. This will maintain fresh to strong 
SW winds over the SW Atlantic, in between the Bahamas and 
Bermuda, through Sat morning. As the low pressure off the SE US 
coast weakens, gentle to moderate winds will prevail over the 
area Sat afternoon through the weekend and into early next week. 
Enhanced thunderstorms will continue over portions of the western
Atlantic, including the Bahamas, through Sat morning. 

$$
GR