[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 291204
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
704 AM EST Mon Jan 29 2018

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 0600 UTC surface analysis and satellite imagery through
1130 UTC.

...SPECIAL FEATURES...

Atlantic Ocean Gale Warnings: A 1033 mb high pressure center is
to the north of the area near 39N53W, and it is supporting
sustained wind speeds to near gale force, to the south of 22N
between 60W and 76W. A second area consists of : a tight pressure
gradient persists between the high pressure and a 1011 mb low
pressure center that is near 32N45W. The low pressure center will
drift south of 30N this morning. Wind speeds are reaching gale
force within 240 nm of the western quadrant of the low pressure
center, and will persist into the afternoon to the north of 29N
between 49W and 52W, and then diminish late today as the low
pressure center weakens. Please read the latest NHC High Seas
Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more
details about this event.

Caribbean Sea Gale Warning: The combination of a 1033 mb high
pressure center that is in the western Atlantic Ocean, and lower
pressure in South America, is supporting minimal gale-force wind
speeds near the coast of Colombia, with seas in the 12 to 15 feet
range. Expect winds to gale-force primarily late at night and
into the early morning hours through Tuesday, and possibly well
into next week. Please read the latest NHC High Seas Forecast
under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details
about this event.

Gulf of Mexico Gale Warning off Veracruz, Mexico : A cold front
reaches from the Big Bend area of FLorida in the northeast Gulf
to the far southwest Gulf near 18.5N93W. Colder and drier air
behind the front will support winds to gale-force off the coast
of Veracruz, starting later today and persisting through tonight,
to the south of 21N and to the west of 95W, with seas building to
8 to 12 feet. The wind speeds and sea heights will diminish to
less than gale-force through early Tuesday as high pressure
builds in the wake of the front. Please read the latest NHC High
Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for
more details about this event.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal sections of Sierra
Leone near 08N12W, to 07N16W. The ITCZ continues from 07N16W, to
the Equator along 48W. Precipitation: isolated moderate to locally
strong rainshowers are from 07N southward from 50W eastward.
Rainshowers are possible elsewhere from 10N southward from 60W
eastward.

...DISCUSSION...

...THE GULF OF MEXICO...

Please read the SPECIAL FEATURES section for details in reference
to an upcoming gale-force wind event in the SW Gulf of Mexico.

Fresh to strong northerly winds follow the front over the
northwest Gulf. Fresh southeast winds are active over the Straits
of Florida, but are starting to diminish from west to east ahead
of the approaching front. A few showers are active over the far
eastern Gulf ahead of an upper trough pivoting across the lower
Mississippi Valley. These showers will shift east of the area
tonight, and no significant convection is noted across the Gulf
at this time. The low pressure over the western Florida Panhandle
will strengthen and move toward the Carolina coast tonight
dragging the cold front eastward across the remainder of the Gulf
waters by late Monday. High pressure will build in the wake of the
front allow winds and seas to diminish across the region although
fresh easterly may persist across the Straits of Florida through
mid week. Looking ahead, another front may enter the northern Gulf
by late week, bringing another round of fresh northerly winds.

...THE CARIBBEAN SEA...

Please read the SPECIAL FEATURES section for details regarding
the gale-force wind conditions near the coast of Colombia.

The main driver through the short term will continue to be the
strong high pressure north of the area, supporting the gale winds
off Colombia, but also fresh to strong trade winds through much
of the eastern and central Caribbean, including the Windward
Passage. Buoy and altimeter data show seas of 8 to 12 ft in the
area of strong winds. Scattered showers and thunderstorms are
ongoing over the Yucatan Channel and far northwest Caribbean. The
gradient will loosen across the region as the high pressure shifts
east ahead of a cold front sweeping across the Gulf of Mexico
today and into the northwest Caribbean tonight. The front will
stall from roughly the Windward Passage to central Honduras by mid
week, bringing fresh to occasionally strong northerly winds to the
northwest Caribbean and the lee of Cuba. Looking ahead, high
pressure building north of the area in the wake of the front will
support fresh to strong trade winds once again over much of the
central and eastern Caribbean and tropical Atlantic west of 55W
late in the week.

...THE ATLANTIC OCEAN...
Please read the SPECIAL FEATURES section for details about gale-
force wind conditions in the western Atlantic Ocean, to the south
of 22N, and developing gale-force wind conditions in the central
Atlantic Ocean.

Scattered moderate to widely scattered strong rainshowers are
within 30 nm to 60 nm on either side of 29N81W beyond 32N78W,
off northeast Florida and the Gulf Stream ahead of an upper level
trough that is digging across the southeastern United States.
Fresh southerly winds are noted off northeast Florida and north of
the Bahamas ahead of a surface low associated with the upper
trough over the western Florida Panhandle and a related cold front
entering the eastern Gulf. 1036 mb high pressure is centered
north of the area near 37N57W, supporting a broad area of fresh
winds east of the Bahamas, with 8 to 12 ft seas. The fresh
southerly flow off northeast Florida will increase late today
ahead of the cold front, which is expected to enter the Atlantic
by late today. The front will reach from near 31N73W to the
northwest Bahamas to the Straits of Florida Mon night, then from
31N64W to eastern Cuba by Tue night. Strong NW winds and building
seas will follow the front.

An upper level cyclonic circulation center is near 31N47W in the
central Atlantic Ocean. A 1011 mb low pressure center is near
32N45W. The 1011 mb low pressure center will enter the area this
morning with an attendant frontal boundary and shear line reaching
toward the Leeward Islands. A surface trough curves along 19N48W
16N50W 12N51W. Widely scattered moderate to isolated strong
rainshowers are within 30 nm to 60 nm on either side of 23N42W
27N40W beyond 32N39W. The low pressure center and front will
weaken substantially as they drift southward through mid week.
Strong SE winds will persist east between the low pressure and
strong high pressure to the northeast over Azores.

Upper level cyclonic wind flow covers the area that is from 14N
northward from 30W eastward. An upper level cyclonic circulation
center is near 30N12W off the coast of Morocco.

A surface ridge passes through 32N28W, to 22N29W, to 10N30W, about
700 nm to the west of Africa. Fresh NE winds are off North
Africa. These winds will increase across the Canary Islands by the
middle of the week, as low pressure off Morocco drifts
southwestward.

For additional information please visit http://www.hurricanes.gov/marine

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