[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 201037
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Mon Nov 20 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 0600 UTC surface analysis and satellite imagery through
1000 UTC.

...SPECIAL FEATURES...

Western and Central Atlantic Gale Warning:
A cold front extends from near 31N63W to the Turks and Caicos
Islands. The pressure gradient between the associated low pressure
and a 1027 mb surface ridge centered NE of the area near 36N29W
is leading to gale force southerly winds in advance of the front
this morning, mainly N of 28N and W of 58W. Seas in this area are
10 to 12 ft. The high pressure is weakening so the gradient should
relax enough such that S winds fall below gale force today.
However, building high pressure from off the Mid-Atlantic U.S. NW
of the cold front will lead to rapidly increasing NW and N winds
later today behind the cold front, and northerly gales will
develop by this evening N of 28N and E of 63W. These gales will
spread E behind the cold front as it crosses 55W late Tue. Winds
should gradually fall below gale force Wed morning. An expanding
area of rough seas of 15 to 20 ft will accompany the gales, and by
Wed morning, a zone of seas in excess of 12 ft should cover
waters N of 22N between 48W and 65W. Low pressure may form along
this cold front around 30N50W by mid-week, and eventually this low
may separate from the front and prolong strong winds in portions
of the Central Atlantic late this week.

Gulf of Mexico Gale Warning:
A cold front will move off the Texas coast tonight, then reach
from near Mobile Bay to just S of Veracruz, Mexico, Tue. Behind
the front, NW to N winds will rapidly increase, with gales
developing by Tue afternoon offshore Tampico, Mexico. These gales
will spread S and impact waters offshore Veracruz, Mexico, Tue
evening through at least midday Wed. Seas the west-central and SW
Gulf will reach 12 to 16 ft. By Wed night, the front will be well
E of the area, and winds and seas will diminish.

Please read the latest High Seas Forecast issued by the National
Hurricane Center at the website -
www.nhc.noaa.gov/text/MIAHSFAT2.shtml and latest Offshore Water
Forecast west of 55W at www.nhc.noaa.gov/marine/offshores.php for
more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from NW Senegal to 15N19W. The ITCZ is
noted to the S, beginning near 08N18W, reaching 04N30W, then
continuing to 08N44W. Numerous moderate to strong convection is
noted from 03N to 12N E of 25W in association with the ITCZ.
Scattered moderate to isolated strong convection is noted from 04N
to 11N between 25W and 35W.

...GULF OF MEXICO...

Please read the Special Features section about a Gale Warning for
portions of the West Central and SW Gulf.

A 1016 mb high pressure centered near the Florida Big Bend is
beginning to weaken and slide east, but is still dominating
weather across the basin. Winds in the eastern Gulf are light to
gentle out of the E and SE. Winds are mainly moderate and SE to S
in the central Gulf, with fresh S winds ongoing in the western
Gulf. Seas are less than 2 ft in the east, 1 to 3 ft in the
central Gulf, and 3 to 5 ft in the western Gulf.

For the forecast, the fresh southerly return flow will prevail
through the western Gulf today, with locally fresh winds likely
offshore Veracruz, Mexico. The cold front will move off the Texas
coast this evening, reach from SE louisiana to near Veracruz Tue
morning, and from northern Florida to the central Bay of Campeche
by Wed morning. Ahead of the front, thunderstorms are likely in
the NW and north-Central Gulf this afternoon through tonight and
the NE Gulf Tue into Tue night.

...CARIBBEAN SEA...

A 1008 mb low pressure near 14N74W is producing scattered
moderate convection within 90 nm of its center. A surface trough
extends NE from this low to Dominican Republic, with numerous
moderate to scattered strong convection noted within 150 nm E of
the trough axis, including the Mona Passage and Puerto Rico. The
eastern extension of the East Pacific Monsoon trough stretches
from the low pressure center SW to near the Panama-Costa Rica
border. The monsoon trough is inducing scattered moderate
convection within about 60 nm either side of its axis. Elsewhere
across the basin, a 1008 mb low pressure centered SW of Jamaica is
engulfed in dry air, precluding any significant convection.

The aforementioned features have disrupted the typical tradewind
regime across much of the basin, thus aside from some moderate E
to SE winds in the eastern Caribbean, winds are mainly light to
gentle in variable directions. The resulting seas are 3 to 5 ft in
the east and central, 2 to 4 ft in the SW, and 1 to 3 ft in the
NW.

For the forecast, the low pressure offshore Colombia will continue
to induce scattered showers and thunderstorms as it drifts W in
the SW Caribbean through mid-week. High pressure building toward
the Greater Antilles Tue into Wed will lead to fresh to locally
strong NE winds in the Windward Passage and just S of Hispaniola.
Elsewhere, winds will be moderate or less into late week.

...ATLANTIC OCEAN...

Please read the Special Features section for details Gale
Warnings in the western and central Atlantic waters.

The cold front associated with the gales extends from SE of
Bermuda to near 22N74W. Numerous moderate to isolated strong
convection is being produced by this cold front, N of 19N between
56W and 59W. Farther east, a stalling cold front extends from near
31N21W to 23N35W to 26N45W. To the east of 30W, there is a narrow
band of scattered convection within 30 nm of the frontal boundary.
Refer to the Monsoon Trough/ITCZ section for additional weather
in the Atlantic Basin.

Outside the ongoing Gale Warning area, fresh to strong SW winds
are found ahead of the western cold front, N of 24N and W of 59W.
Seas in these higher winds are 8 to 10 ft. Elsewhere to the E of
the front, mainly moderate SE winds prevail. Behind the front, N
to NE winds prevail, mainly moderate to fresh but a plume of
strong N winds is spreading S to 28N, between 64W and 70W. Seas in
these strong winds are 8 to 11 ft, with 5 to 7 ft seas elsewhere
on both sides for the front.

With regard to the east Atlantic front, Winds are mainly moderate
and NE to the north of it, and moderate and SE to the S. Seas N of
the boundary are 8 to 10 ft, with 5 to 7 ft seas to the south. In
the tropical Atlantic S of 22N, moderate to fresh trades prevail
with seas of 6 to 8 ft in a combination of wind waves and decaying
long period northerly swell.

For the forecast W of 55W, the aforementioned cold front will
slide E through mid-week, then move E of the region. Large
northerly swell will lead to seas of over 12 ft for areas N of
22N and E of 65W by Wed. Looking ahead, increasing southerly flow
is likely mid-week offshore Florida in advance of the next cold
front.

$$
Konarik
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