[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 290540
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Sun Oct 29 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 0000 UTC surface analysis and satellite imagery through
0515 UTC.

...SPECIAL FEATURES...

Tropical Storm Tammy is near 32.6N 55.2W at 11 PM EDT, and is
moving east-southeast at 15 kt. Maximum sustained winds are 35
kt with gusts to 45 kt, and the minimum central pressure is 1000
mb. Peak seas are 18 ft. Strong westerly shear is displacing the
convection well east of the center. The cyclone is expected to
gradually turn southward before dissipating by the middle part of
next week. Additional weakening is expected, and Tammy is forecast
to become a post- tropical remnant low as soon as tomorrow.
Please read the latest HIGH SEAS FORECAST issued by the National
Hurricane Center at website
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Tammy
NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov
for more details.

Invest 96L: A 1007 mb low pressure is near 22N67W, or a couple
hundred miles north of the Dominican Republic. Scattered moderate
to isolated strong convection is noted from 18N to 26N and
between 63W and 68W. The system is producing strong to near gale-
force winds, especially over the northern semicircle. Seas in the
area are 8-12 ft. The disturbance is showing signs of organization
and a short-lived tropical depression or storm could form later
today while the system moves west-northwestward. By Monday,
however, strong upper-level winds and dry air should end the
chances of further development. An Air Force reconnaissance
aircraft is scheduled to investigate the system later today, if
necessary. The chance of development over the next 48 hours is
medium. Please read the latest Tropical Weather Outlook at
hurricanes.gov for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough reaches the tropical Atlantic through the coast
of Guinea-Bissau near 12N16W and continues southwestward to
06N23W. The ITCZ stretches from 06N23W to 06N40W to 08N59W.
Scattered moderate convection is observed from 03N to 09N and
between 20W and 25W. Scattered moderate to isolated strong
convection is present north of the ITCZ to 16N between 35W and
60W, enhanced by an upper level trough and a surface trough along
45W.

GULF OF MEXICO...

The subtropical ridge off the SE United States continues to
dominate the weather conditions across the Gulf of Mexico,
suppressing the development of deep convection. A modest pressure
gradient between the aforementioned high pressure system and
lower pressures in the deep tropics support fresh to strong
easterly winds, mainly south of 27N and east of 93W. Seas are 5-9
ft in these waters. The strongest winds and highest seas are
occurring in the Florida Straits. Moderate or weaker winds and
seas of 2-5 ft are present elsewhere.

For the forecast, high pressure centered across the middle Atlantic
coastal states will continue to support fresh to locally strong
winds in the southeast and south central Gulf through Sun.
Gentle NE winds are expected by Mon as the pressure gradient
weakens and high pressure settles over the region. A strong cold
front will enter the NW Gulf Mon morning, and move SE across the
entire basin by Wed evening. This front will bring gale force
winds and quickly building seas over the western Gulf beginning
Mon thru Wed night.

CARIBBEAN SEA...

The eastern Pacific monsoon trough extends from the coast of
Nicaragua to the central Caribbean Sea, followed by a surface
trough to eastern Hispaniola. The cyclonic flow brings plenty of
moisture northward, and along with divergence aloft, result in
unsettled weather conditions to the east of the surface features
described. Latest satellite imagery show scattered showers and
isolated thunderstorms affecting the waters offshore Colombia,
Puerto Rico and the Leeward Islands. These storms are also
impacting the islands in the NE Caribbean, causing localized
flooding. The weather pattern will continue to favor scattered
showers and isolated thunderstorms through early next week.

Dry air encompasses the NW Caribbean and Gulf of Honduras,
resulting in only fast-moving, isolated light showers. The
pressure gradient between the ridge off the SE United States and
lower pressures in the deep tropics sustain fresh to strong NE-E
winds in the NW Caribbean, Gulf of Honduras and Windward Passage.
Seas are 4-7 ft in the areas described. The strongest winds are
occurring in the lee of Cuba. Moderate to locally fresh southerly
winds and seas of 4-7 ft are found in the eastern Caribbean.
Elsewhere, light to gentle winds and slight to moderate seas
prevail.

For the forecast, a strong high pressure centered over the middle
Atlantic U.S. coast is combining with surface trough across the
Caribbean along 68W-69W and into the adjacent Atlantic to support
fresh to locally strong NE to E winds in the NW Caribbean. This
trough will shift W-NW through early next week, with winds
diminishing across the NW Caribbean on Sun. Scattered to numerous
strong thunderstorms occurring along and E of the trough will
shift westward with the trough through Mon. Large N-NE swell
across the W Atlantic will continue to move through the NE
Caribbean Passages through Sun. A strong cold front will enter the
NW Caribbean by mid week.

ATLANTIC OCEAN...

Please see the SPECIAL FEATURES section above for information on
Tropical Storm Tammy located well east of Bermuda and on Invest
96L positioned north of the Dominican Republic.

A 1021 mb high pressure system off the SE United States dominates
the SW tropical Atlantic. The pressure gradient between the ridge
and lower pressures in the deep tropics and Invest 96L sustain
fresh to strong NE winds west of 70W. Seas in these waters are
8-12 ft, with the highest seas occurring off the central Bahamas.

The central and eastern Atlantic are under the influence of a
1019 mb high pressure system near 28N40W. A cold front enters the
tropical Atlantic near 31N30W to 29N35W to 31N40W. No deep
convection is seen near the frontal boundary. Moderate to locally
fresh westerly winds and seas of 6-8 ft are evident north of 28N
and between 20W to 35W. The pressure gradient between the ridge
and lower pressures in the deep tropics support moderate to
locally strong easterly winds south of 22N and west of 35W. Wave
heights in the area described are 7-9 ft. Farther east, moderate
to locally fresh northerly winds and seas of 6-8 ft are found off
the coast of Africa, mainly east of 22W. Elsewhere, moderate or
weaker winds and moderate seas prevail.

For the forecast W of 55W, Tropical Storm Tammy is near 32.6N
55.2W at 11 PM EDT, and is moving east-southeast at 15 kt.
Maximum sustained winds are 35 kt with gusts to 45 kt, and the
minimum central pressure is 1000 mb. Tammy will weaken to a
remnant low near 32.0N 52.0W Sun morning, move to 30.5N 48.3W Sun
evening, 29.0N 46.0W Mon morning, 27.5N 45.5W Mon evening, 26.5N
46.0W Tue morning, and dissipate on Tue evening. High pressure
across the middle Atlantic coastal states is combining with a low
level trough than extends from S of Tammy to 1007 mb low pressure
located just N of the Mona Passage to produce a large area of
fresh to locally strong winds, with high seas between Tammy and
the Bahamas. This system could become a short-lived tropical
depression or storm over the next day or so. By Monday, upper-
level winds are forecast to become too strong for further
development as the system turns northward to the east of the
northwestern Bahamas. These high seas will slowly subside through
Mon. The low pressure is expected to move NW and parallel to the
Bahamas Sun through Mon, accompanied by strong winds and very
active weather. A strong cold front will enter the NW waters Wed
morning.

$$
DELGADO
This weather bulletin was brought to you by:
www.nashvilleweather.net