AXNT20 KNHC 090005
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Thu Dec 8 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 1800 UTC surface analysis and satellite imagery through
Central Atlantic Storm Warning: A non-tropical low pressure area
with a central pressure of 979 mb is located about 815 nautical
miles east-southeast of Bermuda near 29N47W. The system continues
to produce an extensive area of showers and thunderstorms N of 30N
while scattered showers encompass an area N of 18N between 25W
and 55W. However, the low remains embedded within a frontal zone
while it moves east-northeastward at 20 kts toward colder waters
and interacts with a mid-latitude trough. Therefore, it is
unlikely that the low will transition to a subtropical or tropical
Storm force winds remain in the NW quadrant of the low within 90
nm of the low center, however a large area of gale force winds
are within 300 nm west of the low center and 415 nm E of the low
center. A larger area of fresh to strong winds extends south to
17N between 32W and 62W. Seas are peaking at 30 ft within the
area of storm force winds, with very rough to high seas covering
an extensive area between 28W and 74W. Storm conditions will move
E of the area tonight. Large long-period north to northeast swell
will impact the Atlantic waters and Caribbean Passages between
the southeastern Bahamas and the E Caribbean producing high seas
into the start of next week, with large E swell reaching the
Florida offshore waters N of 26N early Fri through Sat.
More information about this system, including the associated
Storm Warning, can be found in the High Seas Forecasts issued by
the National Hurricane Center at
The monsoon trough extends from the coast of W Africa near 10N14W
to 06N16W. The ITCZ continues from 06N16W to 04N31W to 06N42W.
Scattered moderate convection is observed from 01N to 12N between
29W and 50W.
GULF OF MEXICO...
A 1024 mb surface high is centered over the Mississippi coastal
waters supporting generally fair weather conditions and mainly
gentle to moderate easterly breezes over the basin. Seas remain in
the 3 to 5 ft seas over the western, central and far southern
portion of the basin, with seas below 3 ft north of 28N and about
120 nm offshore the FL west coast.
For the forecast, high pressure will meander in the vicinity of
the NE Gulf through the upcoming weekend. The ridge will shift
eastward early next week as a cold front approaches the NW Gulf.
Gentle to moderate winds will prevail through the weekend,
increasing to moderate to fresh early next week. Winds may
increase to strong speeds and seas build up to 8 ft late Tue in
the NW Gulf.
The pressure gradient between subtropical high pressure in the
western Atlantic and lower pressure over Colombia is generating
moderate to fresh NE winds west of 70W in Caribbean Sea,
including the Windward Passage, where seas are in the 6 to 7 ft
range. In the E Caribbean, gentle to moderate N winds prevail
with mainly 5 ft seas. Seas may be up to 6 ft near Atlantic
For the forecast, the intense low pressure system in the central
Atlantic is gradually lifting northeastward. Large NE swell across
the central Atlantic will move through the Caribbean Passages and
Tropical Atlantic waters through Sat. The current weather pattern
will sustain NE-E winds across much of the forecast waters. Fresh
to pulsing strong NE-E winds will occur in offshore Colombia into
early next week. Moderate to fresh NE winds, occasionally pulsing
to strong speeds, will affect the Caribbean Passages and the lees
of the Greater Antilles into Sat.
Please read the Special Features section above for details on a
storm force low pressure system, affecting the waters north of
18N between 35W and 60W.
This intense low pressure system over the subtropical Atlantic,
near 29N47W, continues to produce an extensive area of showers and
thunderstorms, mainly north of the center.
Elsewhere, fresh to strong N to NE winds from the Caribbean
Islands extend to 31N between 61W and 75W, where seas are rough
to very rough due to the low pressure system in the central
Atlantic. A weak pressure pattern prevails off central and
northern Florida, with gentle winds and 4-6 ft seas in the far
western Atlantic. In the far eastern Atlantic, a weak high
pressure center prevails offshore W Africa, allowing for gentle to
moderate anticyclonic flow mainly east of 35W, where seas are 5
to 9 ft.
For the forecast W of 55W, the low pressure system is forecast to
accelerate tonight and Fri into the north Atlantic and strengthen
into a powerful non-tropical cyclone. Large long- period north to
northeast swell will impact the Atlantic waters and Caribbean
Passages between the southeastern Bahamas and the E Caribbean
producing high seas into the start of next week, with large E
swell reaching the Florida offshore waters N of 26N early Fri