[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 292251
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
651 PM EDT Wed Jul 29 2020

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 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1800 UTC surface analysis and satellite imagery through
2250 UTC.

...SPECIAL FEATURES...

Potential Tropical Cyclone Nine is centered near 16.4N 65.6W at
29/2100 UTC, or about 105 nm S of St. Croix, moving WNW at 20
kt. Estimated minimum central pressure is 1004 mb. Maximum
sustained wind speed is 40 kt with gusts to 50 kt. Scattered
strong convection extends out 300 nm from the center in the NE
quadrant and 260 nm SW quadrant. Heavy rain may lead to
life-threatening flash flooding over the Leeward Islands,
Virgin Islands, Puerto Rico and the Dominican Republic today
into Thu. ASCAT pass shows that tropical storm force winds of
35-40 kt exist in the NE quadrant in the area between 150-270
nm NE of the center. These winds are currently affecting the
northern Leeward Islands, and will be spreading to the Virgin
Islands. The highest seas this afternoon and evening are expected
on the Atlantic Ocean side of the northern Leeward and Virgin
Islands, with peak seas of 18 ft.

PTC Nine is forecast to remain at tropical storm strength as it
interacts with Hispaniola on Thursday, and Cuba and the Bahamas
on Friday. Please read the latest NHC Public Advisory at
https://www.nhc.noaa.gov/text/MIATCPAT4.shtml and Forecast/
Advisory at https://www.nhc.noaa.gov/text/MIATCMAT4.shtml for
more details.

...TROPICAL WAVES...

A tropical wave has been added to the analysis with axis along
20W from 03N-18N, moving W at 15 kt. Numerous moderate scattered
strong convection is within 260 nm W and 180 nm E of the wave
axis from 07N-13N.

An Atlantic tropical wave is along 35W from 21N southward,
moving W at 20 kt. Scattered moderate convection is seen from
03N-08N Between 32W-39W.

A Caribbean Sea tropical wave is along 77W from 19N southward,
moving W at 20 kt. Scattered moderate convection is near eastern
Panama where the wave axis meets the east Pacific monsoon trough.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal sections of
Mauritania near 18N16W to 10N30WW to 08N45W. The ITCZ
continues from 08N45W to 09N53W. Scattered moderate convection
is observed from 05N-13N between 23W-28W and from 02N-07N
between 39W-48W.

GULF OF MEXICO...

A ridge extends across the northern Gulf supporting gentle to
moderate E to SE winds and 2 to 4 ft seas across the basin,
except for fresh winds and 3 to 5 ft seas off the west coast
of the Yucatan peninsula. An upper-level low over NE Mexico is
generating upper-level diffluence over the west-central Gulf,
enhancing scattered moderate showers and tstorms over the w
western Gulf, west of 95W.

For the forecast, a ridge will dominate the Gulf waters
through Fri, supporting mainly gentle to moderate return flow.
Beyond that, much will depend on the track and intensity of
Potential Tropical Cyclone Nine, currently located over the
eastern Caribbean. This system may approach the Florida Straits
and far southeast Gulf by Sat and Sun.

CARIBBEAN SEA...

Potential Tropical Cyclone Nine is currently affecting the
eastern Caribbean, east of 60W and north of 13N. See Special
Features section above for the current details on Nine.
Several stations on Guadeloupe and Martinique reported
24-hour rainfall amounts ending at 29/1200 UTC between 3 and
4 inches. For the forecast, seas as high as 10-15 ft are
forecast through tonight for portions of the NE Caribbean in
the waters south of Puerto Rico. Tropical storm force winds
are forecast to be in the Mona Passage tonight, near
Hispaniola Thu, and in the Windward Passage late Thu and Thu
night. The NW Caribbean should monitor the progress of Nine
in case the track shifts farther south. Winds and seas will
largely diminish over the eastern Caribbean Fri, except for
an area of swell to at least 8 ft that will penetrate through
the Mona Passage.

Tropical storm conditions will continue across portions of the
Leeward Islands, the U.S. and British Virgin Islands and Puerto
Rico through tonight. These conditions are forecast to reach
portions of the Dominican Republic and Haiti by late tonight
or early Thursday.

ATLANTIC OCEAN...

A small upper-level trough off the SE coast of the U.S. is
inducing upper-level divergence to the SE of the trough. This
is enhancing scattered moderate convection east of Florida and
north of the NW Bahamas, north of 26N between 77W-81W. A surface
ridge extends across the Atlantic from a 1024 mb high near
31N59W. Convection related to PTC Nine is currently occurring
south of 23N between 59W-67W. The ASCAT pass showed that winds
over 25 kt associated with the circulation of PTC Nine were
confined to areas south of 24N between 56W-66W at that time.

Potential Tropical Cyclone Nine has max sustained winds of 40 kt
gusts 50 kt. PTC Nine will move to 17.5N 68.1W Thu morning,
inland to 19.2N 71.0W Thu afternoon, 20.9N 74.2W Fri morning,
22.3N 76.9W Fri afternoon, 23.6N 78.9W Sat morning, and inland to
25.5N 80.8W Sat afternoon. PTC Nine will move inland over 28.6N
82.1W Sun afternoon. Tropical storm conditions are expected to
reach the southeastern Bahamas and Turks and Caicos Thursday
afternoon.

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