[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 191802
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Thu Nov 19 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 1200 UTC surface analysis and satellite imagery through
1715 UTC.

...SPECIAL FEATURES...

Gulf of Mexico Gale Warning: Strong autumn high pressure will
continue to build southward across the Gulf of Mexico behind a
stationary front that extends from western Cuba to across the
Yucatan Channel and to the northern Yucatan Peninsula. The high
pressure will continue to create a very tight gradient between
it and the front leading to strong northeast winds. Frequent
gusts to 35 kt may occur in the Straits of Florida. Hazardous
conditions are expected between the wind waves against the flow
of the Gulf Stream through the Straits of Florida, and due to a
southeast swell propagating through the Yucatan Channel. Seas
will be highest in the Straits of Florida today, 10-16 ft. Please
read the latest NWS High Seas Forecast issued by the National
Hurricane Center at website https://www.nhc.noaa.gov/text/
MIAHSFAT2.shtml for more details.

Atlantic Gale Warning: A cold front extends from 31N54W to
north-central Cuba. Scattered showers are noted within 180 nm
either side of the front. Strong high pressure continues to build
in behind the front supporting strong northeast winds. Frequent
gusts to gale force are forecast from 22N-27N and west of the
front today, and then from 22N-27N between the front and the
Bahamas. Large and hazardous seas are possible in the Gulf Stream
between the Bahamas and Florida through the Straits of Florida,
with large fresh seas also developing NE of the Bahamas through
the end of the week in the continued northeast flow. Please read
the latest NWS High Seas Forecast issued by the National
Hurricane Center at website
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details.

...TROPICAL WAVES...

A tropical wave is along 47W from 15N southward, moving westward
around 10 kt. Scattered moderate to isolated strong convection
is from 00N-11N between 40W-55W.

A tropical wave is along 66W from 20N southward to central
Venezuela, moving westward at 10-15 kt. Scattered showers are
within 120 nm of the wave axis.

A tropical wave is along 77W/78W from near eastern Jamaica
to eastern Panama, moving westward around 10 kt. Isolated
moderate convection is within 120 nm of the wave axis.

...MONSOON TROUGH/ITCZ

The monsoon trough axis extends from the coast of Africa near
08N13W to 08N20W. The ITCZ axis extends from 08N20W to 04N40W to
05N46W, then resumes west of a tropical wave near 05N48W to
03N51W. Besides the convection mentioned in the tropical wave
section, scattered moderate convection is along the coast of
Africa from 02N-06N between 00W-12W.

GULF OF MEXICO...

See the Special Features section for details on a Gale Warning
in effect in the southeast Gulf of Mexico.

High pressure is northeast of the basin over the Carolinas.
Outside of the gale conditions described above, moderate to fresh
E-SE flow and seas of 6-9 ft in NE swell are noted north of 22N
and west of 90W, with fresh to strong NE flow and 7-10 ft seas in
NE swell elsewhere.

Winds and seas will diminish through late Sat across the basin.
Looking ahead, a weak cold front will move into the northwest
Gulf and stall late Sun through Mon.

CARIBBEAN SEA...

A 1011 mb low pressure area is noted in the southwest
Caribbean north of the Panama Canal near 11N80W. Isolated
moderate convection is from 07N-13N between 76W-82W. Development,
if any, of this system is expected to slow to occur during the
next several days while it drifts westward across the
southwestern Caribbean Sea. Regardless of tropical cyclone
formation, areas of heavy rain are possible during the next
several days from Nicaragua southward across Central America
and into Colombia. These rains could cause new flooding
concerns,
especially across previously inundated areas. Please read the
latest Tropical Weather Outlook issued by the National Hurricane
Center at website www.nhc.noaa.gov/text/MIATWOAT.shtml for more
details.

Scattered moderate convection is noted in the Gulf of Honduras.
Additional scattered moderate convection is noted in the central
Caribbean between 69W-75W due to a mid-to-upper level trough.
Moderate to fresh trades and seas of 4-6 ft are noted east of
72W, with mainly moderate trades W of 72W, except moderate to
fresh south of 18N.

A stationary front over the Yucatan Channel will gradually
dissipate through Fri. High pressure building N of the front is
supporting strong winds and large seas over the far
northwestern Caribbean. These winds and seas will diminish
through Fri as the high pressure weakens, leaving generally
moderate trade winds and slight to moderate seas across the
basin by early next week. Large northerly swell will impact the
Atlantic waters off the Leeward Islands into Mon.

ATLANTIC OCEAN...

See the Special Features section for details on a Gale Warning in
effect for the waters from 22N-27N west of a cold front.

Southeast of the cold front described above, mainly moderate to
fresh trades prevail, except fresh to strong south of 14N east of
55W, and south of 29N east of 45W. Seas are 6-10 ft in mixed
swell with the highest seas noted where the fresh to strong winds are.

The cold front will weaken today, then lift NW and dissipate
through Fri. High pressure N of the front will support fresh to
strong NE-E winds across most the region through Fri, with
frequent gusts to gale force from 22N-27N through tonight. A
trough will form E of the Bahamas by Fri, and may become a weak
low pressure area between the northern Bahamas and Bermuda by
early next week.

A non-tropical area of low pressure could form between the
Bahamas and Bermuda by early next week. The system could
gradually develop subtropical characteristics through the middle
of next week while it moves northeastward. Please read the
latest Tropical Weather Outlook issued by the National Hurricane
Center at website www.nhc.noaa.gov/text/MIATWOAT.shtml for more
details.

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