AXNT20 KNHC 171701
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Wed Aug 17 2022
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 1200 UTC surface analysis and satellite imagery through
An Atlantic Ocean tropical wave is along 19W, from 20N
southward, moving westward from 10 knots to 15 knots.
Precipitation: widely scattered moderate to isolated strong is
from 06N to 14N between Africa and 25W.
An Atlantic Ocean tropical wave is along 45W, from 21N
southward, moving westward from 15 knots to 20 knots.
Precipitation: isolated moderate is within 420 nm on either side
of the tropical wave.
A Caribbean Sea tropical wave is along 84W/85W, from 20N
southward, moving westward from 10 knots to 15 knots.
Precipitation: scattered to numerous moderate to strong is
within 200 nm to the west of the tropical wave, and within 100
nm to the east of the tropical wave, from 17N to 20N. Other
isolated moderate to locally strong is elsewhere from 13N
northward from Jamaica westward. This tropical wave is forecast
to move through Central America during the next couple of days.
The wave will continue into the southwestern corner of the Gulf
of Mexico, where it is possible that an area of low pressure may
form on Friday. Some gradual development of this system is
possible, while it moves northwestward, through the southwestern
Gulf of Mexico, through the weekend.
The monsoon trough passes through the coastal areas of Guinea-
Bissau near 19N16W, to 16N20W 12N30W 09N42W. The ITCZ is along
08N47W 07N54W. Precipitation: isolated moderate to locally
strong is from 10N southward between 29W and 60W.
GULF OF MEXICO...
Broad and weak surface anticyclonic wind flow spans the area. A
1016 mb high pressure center is near 28N91W. The surface
pressure gradient is flat and weak.
An upper level cyclonic circulation center is in the
southwestern corner of the Gulf of Mexico. Upper level cyclonic
wind flow covers the Gulf of Mexico and parts of inland Mexico
28N southward from 102W eastward. An inland frontal boundary is
passing through the southern sections of Georgia and Alabama,
toward central Mississippi. Precipitation: scattered moderate to
isolated strong is between the upper level cyclonic circulation
center and the coast of Mexico between 92W and 96W. Isolated
moderate to locally strong is within 75 nm of the coast of
Mexico from 24N southward, and from 26N to 29N between 82W in
Florida and 88W.
Moderate ENE-NE winds are offshore NW and W parts of the Yucatan
Peninsula. Light to occasionally moderate anticyclonic winds are
elsewhere. The sea heights range from 3 feet to 4 feet in the
eastern Bay of Campeche and in the W Gulf waters. The sea
heights range from 1 foot to 3 feet in the remainder of the Gulf
A 1016 mb high pressure centered near 28N91W will drift ESE in
the north-central Gulf through tonight. A stalled front across
the NE Gulf coast states will sink S and settle north of the
northern Gulf today and linger in this area through Thu. This
will increase winds across the northeast and north-central Gulf
with moderate westerly winds. A tropical wave in Honduras and
the northwestern Caribbean Sea is forecast to move across
Central America during the next couple of days and emerge in the
Bay of Campeche, where an area of low pressure may form on
Friday. Some gradual development of this system is possible,
while it moves NW, into the southwestern Gulf of Mexico through
Broad upper level anticyclonic wind flow covers the areas that
are from the Windward Passage westward. Comparatively drier air
in subsidence in water vapor imagery covers the remainder of the
A weak pressure gradient supports moderate or weaker easterly
trade winds, in most of the Caribbean Sea. The exceptions are:
locally fresh to strong trade winds off N Colombia and in the
Gulf of Venezuela, and fresh to local strong winds in the Gulf
of Honduras. The sea heights range from 3 feet to 5 feet in the
south central Caribbean Sea and in the Gulf of Honduras. The sea
heights range from 1 foot to 3 feet in the remainder of the
The monsoon trough is along 10N/11N, between 74W in Colombia,
and beyond the border of Costa Rica/Nicaragua, into the eastern
Pacific Ocean. No significant deep convective precipitation is
related directly to the monsoon trough.
A tropical wave in the far western Caribbean Sea continues to
generate heavy showers and thunderstorms across the NW basin.
This active weather is expected to shift gradually westward with
the tropical wave through tonight. Surface ridging building N of
the region is supporting generally moderate trade winds across
much of the basin, except for fresh winds in the south central
Caribbean Sea. The ridge will strengthen modestly behind the
exiting tropical wave today through Fri night, gradually to
bring a return of fresh to strong trade winds across the south
central basin. A tropical wave will move across the Tropical
Atlantic waters Thu night, across the eastern Caribbean Sea on
Friday, and the central Caribbean Sea Fri night and Sat.
An upper level trough passes through 31N51W, to 26N60W, to the
Bahamas near 23N77W. Precipitation: widely scattered moderate to
isolated strong is to the northwest of the line that runs from
31N62W to 24N70W to 23N80W, and from 29N northward between 45W
and 55W. A surface trough curves through the area that is from
17N in the Caribbean Sea to 26N in the Atlantic Ocean between
64W and 66W. Precipitation: isolated moderate to locally strong
is from 17N in the Caribbean Sea to 23N in the Atlantic Ocean
between 59W and 70W.
Gentle moderate SW winds are from 28N northward between 67W and
79W. Broad surface anticyclonic wind flow covers the Atlantic
Ocean from 20N northward from 60W eastward. Light to moderate
anticyclonic winds, and sea heights that range from 3 feet to 5
feet, are from 55W westward. Gentle to locally fresh easterly
trade winds, and sea heights that range from 4 feet to 7 feet,
are between 22W and 55W. Fresh to strong NE winds, and sea
heights that range from 7 feet to 11 feet, are from 18N
northward from 22W eastward, with the strongest winds and the
highest seas occurring off NW Mauritania and SE Western Sahara.
Moderate wind speeds or slower, and sea heights that range from
3 feet to 5 feet, are elsewhere.
Surface ridging is building again across the region, and it is
expected to prevail through Fri before lifting north on Sat. A
stalled frontal boundary just NW of the area will drift SE to
near the NE Florida waters today and linger across the region
through Thu, which will maintain active weather N of 28N between
Florida and 68W.