[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 151054
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Fri Dec 15 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
1020 UTC.

...SPECIAL FEATURES...

Central Atlantic Gale Warning: A 1003 mb low is located near
27.5N43W. Overnight scatterometer data depicted southwest gale-
force winds east through southeast of the low, while strong north
to northeast winds were depicted west and northwest of the low.
Recent altimeter data show that seas have begun to subside and
are now 10 to 13 ft west and northwest of the low, N of 20N, but
remain 10 to 14 ft east of the low. In addition, satellite
imagery shows a cluster of scattered moderate to isolated strong
convection north of 23N between 37W and 40W. The low and
associated convective activity will continue to shift north-
northeastward through today. As it does, the tight pressure
gradient producing the gales will weaken just enough to allow for
the gale- force winds to drop to just below gale criteria by
midday. Seas will continue to slowly subside through today.

Atlantic Significant North Swell: Large north swell due to
ongoing near gale force winds associated with the low pressure
system mentioned above will continues to sustain 12 to 16 ft
seas from 22N to 31N between 38W and 50W. This swell will
subside below 12 ft by late Fri morning west of 43W. Seas east of
43W and north of 24N will gradually shift N-NE with the low
center, and exit the area by early Sat morning.

Western Atlantic and Florida Offshore Waters Gale Warning and
Significant Swell Event: A slow moving cold front extends from
31N55W to the northwest Bahamas near 25N76W, where it becomes
stationary and continues through the Florida Straits. Gale force
winds continue this morning over waters between the Bahamas and
Florida, from the front to 25.5N to 29N. Seas within these areas
of winds are 12 to 18 ft. 1037 mb high pressure is across the
middle Atlantic States this morning. The prevailing tight
pressure gradient between this high pressure and the front will
support near gale force to gale force winds offshore Florida
through the weekend. Seas have likely peaked around 18 ft between
27N and 29N N of the front this morning and will subside very
slowly through early Sat night before low pressure exits NE
Florida. Seas of 12 to 14 ft will spread southward between 60W and
the north facing coasts of the Bahamas, reaching 22N by Sat
morning. This front will become stationary and aligned along 23N
by the weekend.

Gulf of Mexico Gale Warning: Strong high pressure building
across the eastern United States is supporting NE to E strong to
near-gale force winds over the northern and eastern Gulf of
Mexico as depicted by recent scatterometer pass, and gale-force
winds across the SE Gulf from 24N to 26N. These easterly gales
are expected to persist across the offshore waters of SW Florida
through early afternoon before diminishing slightly. Low pressure
will form in the SW Gulf Fri night then move NE and into NE Florida
Sat night. This will produce additional gales in the NE Gulf. A
cold front will trail from the low, exiting the Gulf by early Sun.
Strong north winds will spill into the western Gulf Sat and Sat
night behind the front. High pressure will then settle in over the
area through early next week allowing for marine conditions to
improve. Expect widespread showers and thunderstorms over most of
the central and eastern Gulf through early Sun.

For more details on the Significant Swell and Gale Warnings,
please read the latest High Seas Forecast issued by the National
Hurricane Center at
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml.

...MONSOON TROUGH/ITCZ...

The monsoon trough remains across equatorial Africa. The ITCZ
begins near 05N10W to 06N31W to 04.5N49W. Scattered moderate
isolated strong convection is noted about the ITCZ, from 02N to
06N between 12W and 41W.

...GULF OF MEXICO...

Please read the SPECIAL FEATURES section for details on the Gale
Warning in the E Gulf and a forming gale force low pressure
system developing this weekend.

A stationary front related to the boundary in the western
Atlantic Gale force winds described in the SPECIAL FEATURES,
enters the Gulf of Mexico through the Florida Straits to near
22N94W. An overnight ASCAT pass depicted a large swath of strong
to near gale force NE to E winds N of the boundary. Large seas of
10 to 16 ft prevail across a large portion of the E and central
Gulf and extend to 95W. A surface trough is depicted in the SW
Gulf. Moderate to fresh NE winds shift to the NW within 90 nm of
the Mexican coast, and south of 20N surrounding the feature.
Broken to overcast multilayered clouds along with scattered to
numerous showers and areas of moderate rain are over the basin
north of 25N.

For the forecast, strong high pressure building across the
eastern United States will support strong winds over the northern
and eastern Gulf of Mexico today, with easterly gales offshore of
SW Florida through this afternoon. Low pressure will form in the
SW Gulf Fri night, then move NE Sat and inland across the Florida
Big Bend Sat night. This will produce additional gales in the NE
Gulf beginning Sat. A cold front will trail from the low, exiting
the Gulf by early Sun. Strong north winds will spill into the
western Gulf Sat and Sat night behind the front. High pressure
will then settle in over the area through early next week allowing
for marine conditions to improve. Expect widespread showers and
thunderstorms over most of the central and eastern Gulf through
early Sun.

...CARIBBEAN SEA...

Fresh to strong NE to E winds prevail over most of the central
basin, and across the NW part of the basin north of 18N. Moderate
to fresh winds are noted elsewhere. Seas are up to 9 ft offshore
Colombia, 8 to 10 ft across the central basin and 8 to 11 ft
across the Yucatan Channel. Isolated moderate convection is across
the Gulf of Honduras.

For the forecast, Strong high pressure N of the region across the
eastern U.S. will support fresh to strong trade winds across
mOST of the basin N of 15N today, before the high pressure shifts
E and weakens, causing winds to gradually diminish through late
Sat. A cold front will move through the Yucatan Channel and into
the NW Caribbean Sat night into Sun, and reach from the Windward
Passage to Costa Rica by Tue. Fresh to strong NW to N winds will
follow this front.

...ATLANTIC OCEAN...

Please read the SPECIAL FEATURES section for details about the
the ongoing Gale Warnings and the Significant North Swell. Strong
N to NE winds prevail north of the front to beyond 31N, with seas
of 10 to 13 ft E of 70W.

Aside from those conditions described above under SPECIAL
FEATURES, an area of fresh to locally strong NE to E winds is
noted south of the front and west of 60W to the Greater Antilles,
where seas are 8 to 10 ft. Elsewhere, moderate to fresh winds
along with moderate seas prevail throughout the rest of the basin.

For the forecast, the cold front will sink southward and become
stationary along 23N by Sat. The pressure gradient between the
strong high pressure building north of the area and the front will
result in near gale to gale force northeast to east winds and
high seas over the waters W of 70W and north of 24N into Fri
afternoon. The front will then lift N as a warm front Sat
afternoon through Sun, in advance of Gulf of Mexico low pressure
that will move NE across Florida Sat night. This low will move
through the NW Atlantic waters Sun through Sun night, when a large
area of southerly gales is expected E of the low. Widespread
showers and thunderstorms are expected over most of the western
half of the area through the weekend.

$$
Stripling
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