[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 132107
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Tue Sep 14 2021

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
2030 UTC.

...SPECIAL FEATURES...

Tropical Storm Nicholas is centered near 27.4N 96.4W at 13/2100
UTC or 60 nm S of Port Oconnor Texas moving NNE at 10 kt.
Estimated minimum central pressure is 1000 mb. Maximum sustained
wind speed is 55 kt with gusts to 65 kt. Peak seas are currently
21 ft. Numerous moderate and isolated strong convection is noted
north of 25N and west of 92W, with scattered moderate convection
elsewhere north of 22N and west of 90W. On the forecast track, the
center of Nicholas is expected to make landfall along the central
Texas coast later tonight. Some additional strengthening
is forecast this evening, and Nicholas could be near hurricane
strength when it reaches the central Texas coast. Weakening is
anticipated on Tue and Wed while Nicholas moves over land,
weakening to a tropical depression near Wed morning, becoming a
remnant low Thu, and dissipating Fri afternoon. Dangerous storm
surge, as well as flooding at urban and low-lying areas and near
rivers and streams, is likely.
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 is in the Atlantic Ocean near the coast of Africa
along 18W from 04N to 17N, moving W at around 10 kt. Numerous
moderate and scattered strong convection is noted from 09N to 15N
between 11W and 18W, mainly over land. Scattered moderate
convection is noted from 06N to 11N between 19W and 23W. The
National Hurricane Center is monitoring this feature and there is
a low chance of tropical cyclone formation through the next 48
hours, and a high chance through the next 5 days. Please read the
latest Atlantic Tropical Weather Outlook at www.hurricanes.gov for
more information.

A tropical wave is in the Atlantic Ocean along 35W from 19N
southward, moving W at around 15 kt. Associated convection is
described in the section below.

A tropical wave is in the Atlantic Ocean along 58W from 20N
southward, moving W at 15 to 20 kt. Drier air at the mid-levels
is hindering any significant convection near this wave.

A tropical wave is in the Caribbean Sea along 75W near the
approach to the Windward Passage from 20N southward to across
north-central Colombia, moving W at around 10 kt. Scattered
moderate and isolated strong convection is noted in the southwest
Caribbean Sea from 09N to 13N between 73W and 85W, mainly
associated with the eastern extent of the Pacific Ocean monsoon
trough.

A tropical wave is exiting the NW Caribbean Sea near eastern
Belize along 88W from 18N southward into the Pacific Ocean, moving
W at around 10 kt. No significant convection is noted.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from near The Gambia and Senegal border
at 13N17W to 09N26W to 07N45W. Scattered moderate and isolated
strong convection is noted from 05N to 10N between 33W and 44W.

...GULF OF MEXICO...

Refer to the Special Features section above for details on
Tropical Storm Nicholas moving northward across the NW Gulf.

Convergent fresh to strong SE winds feeding toward Nicholas are
triggering scattered showers and isolated thunderstorms over the
Bay of Campeche. Convergent trade winds are producing scattered
showers and isolated thunderstorms across the SE Gulf, including
the Straits of Florida and the Florida Keys.

Outside of Nicholas, fresh to strong SE to S winds with seas at 6
to 9 ft across the W central Gulf. Elsewhere, mainly gentle to
moderate E-SE winds. Seas are 2 to 4 ft in the eastern Gulf, and 4
to 7 ft elsewhere outside of Nicolas.

For the forecast, Nicholas will move to 28.7N 96.1W Tue morning,
inland to 29.9N 95.3W Tue afternoon, move inland and weaken to a
tropical depression near 30.4N 94.4W Wed morning, then to 30.9N
92.9W Wed afternoon, to 31.1N 91.4W Thu morning, and become a
remnant low as it moves to 32.0N 90.6W Thu afternoon. Nicholas
will dissipate Fri afternoon.

...CARIBBEAN SEA...

Convergent trades are coupling with divergent winds aloft to
produce scattered showers and thunderstorms over the NE portion
of the basin north of 12N and east of 68W, including the Leeward
Islands. Late afternoon/early evening showers and thunderstorms
are over the Greater and Lesser Antilles. Refer to the Tropical
Waves and Monsoon Trough/ITCZ sections for additional convection
in the Caribbean Basin.

Fairly tranquil marine conditions are noted across the basin with
gentle with locally moderate trades. Seas at 3 to 5 ft across the
majority of the waters, except 2 to 4 ft north of Venezuela.

For the forecast, moderate to fresh trades will prevail across
the basin through Wed. By mid-week, fresh E winds return in the
Gulf of Honduras and south-central Caribbean, and will then continue
through the forecast period.

...ATLANTIC OCEAN...

An old frontal boundary that was reaching from southeast of
Bermuda to near the Treasure Coast of Florida has dissipated.
Even so, plentiful moisture remains with scattered showers and
isolated thunderstorms across much of the basin west of 60W.
Refer to the Tropical Waves and Monsoon Trough/ITCZ sections for
additional convection.

Outside of any convection, fairly tranquil marine conditions
prevail across the basin with gentle to moderate trades. Seas of
3 to 6 ft dominate as well, except 5 to 8 ft north of 28N between
the Canary Islands and 35W.

For the forecast west of 65W, quiescent conditions will prevail
through Wed. Meanwhile, an area of low pressure is forecast to
form by midweek a couple of hundred miles north of the
southeastern or central Bahamas as a tropical wave interacts with
an upper-level trough. Some gradual development of this system is
possible thereafter, and a tropical depression could form later
this week while the system moves NW across the western Atlantic.
This system has a low chance of formation in the next 48 hours,
and a medium chance through the next 5 days. Please read the
latest Atlantic Tropical Weather Outlook at www.hurricanes.gov for
more information.

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