Tropical Weather Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
008
AXNT20 KNHC 160012
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
805 PM EDT Sun Apr 15 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 1800 UTC surface analysis and satellite imagery through
2300 UTC.

...SPECIAL FEATURES...

...Atlantic Gale Warning...

A cold front over the eastern Gulf of Mexico will move E across
the west Atlantic area beginning later tonight, extending from
31N77W to 27N80W by early Monday. Gale- force winds are expected
north of 26N east of the front to 74W starting this evening,
with seas ranging between 8-12 ft outside of the Bahamas. These
conditions will begin to improve by late Monday morning. For more
details, please refer to the High Seas Forecast under AWIPS/WMO
headers HSFAT2/FZNT02 KNHC.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal plains of western
Africa near 10N13W to 04N21W. The ITCZ continues from 04N21W to
03N30W to 02N50W. Isolated moderate convection is observed from
02N to 08N between 13W and 25W, and from 00N to 03N between 43W
and 51W.

...DISCUSSION...

GULF OF MEXICO...

Fresh to strong northerly winds follow a late season cold front
that extends from 30N84W to 21N88W. A pre-frontal squall line is
quickly moving east, and at 2100 UTC extended from 27N82W to
21N85W. Scattered to numerous showers and thunderstorms along with
gusty winds are noted along and E of the squall line, including
the Yucatan Peninsula and Channel. Seas range between 8-13 ft
along and within about 300 nm W of the front, with the 13 ft
observation over the central Gulf measured by buoy 42001. High
pressure has built over the western Gulf behind the front, with a
1027 high center near 21N98W.

The front will continue moving east across the remainder of the
eastern Gulf through tonight. Winds and seas will diminish into
Monday as high pressure continues to build east across the basin.
The center of the high pressure ridge will reach the NE Gulf by mid
week, which will help to induce fresh to strong SE return flow
will over the northwest Gulf by late Tuesday between the ridge and
lower pressure over the southern Plains. A weaker cold front is
forecast to stall and dissipate over the northern Gulf Thursday.

CARIBBEAN SEA...

Moderate to fresh easterly winds prevail across most of the
basin. An earlier scatterometer passes indicated fresh to strong
east winds off northeast Colombia and near the Gulf of Honduras.
Seas over the south central Caribbean are likely 8 to 10 ft, with
5 to 8 ft elsewhere. NE to E swell over the tropical Atlantic W of
55W has largely decayed to 6 to 8 ft. A pre-frontal trough has
entered the NW Caribbean this evening and is supporting gusty
winds and numerous showers with embedded thunderstorms NW of a
line from 22N82W to 16N87W.

The cold front currently over the southeastern Gulf will enter
the northwest Caribbean later tonight, and stall from central
Cuba to central Honduras late Monday, before dissipating through
late Tuesday. Showers and thunderstorms will continue to progress SE
ahead of the cold front through Monday. Strong NW winds will follow
the front from the coast of Quintana Roo in the Yucatan to the
Gulf of Honduras, before diminishing late Monday. Elsewhere, the fresh to
strong trade winds will continue to pulse near the coast over the
south central Caribbean through mid week, and will expand eastward
to along the coast of Venezuela by late this week.

ATLANTIC OCEAN...

Gale-force winds are expected to develop over the west Atlantic
this evening. Please refer to the section above for more details.

High pressure northeast of the area is supporting pulses of
fresh to strong trade winds off Hispaniola, as noted in earlier
scatterometer imagery and ship observations. The strong winds are
noted mainly along the northern coast of Haiti as far west as the
approaches to the Windward Passage.

Strong to near gale-force southerly winds are occurring W of 75W
N of 26N as the cold front over the eastern Gulf of Mexico
approaches. A pre-frontal squall line has reached the waters E of
NE Florida, with the line as a whole extending from 31N81W to
central Florida as of 2100 UTC. Gusty shifting winds and numerous
thunderstorms will accompany this squall line as it moves east
over the western Atlantic waters through Monday. The cold front
will reach the E coast of Florida late tonight, then reach from
31N70W to central Cuba late Monday night. The southern portion
will then stall from 25N70W to E Cuba Tuesday, with the north
portion stalling from 31N60W to 25N67W on Wednesday. The entire
front will then weaken and dissipate later this week. Fresh to
strong winds behind the front will diminish Tuesday and Wednesday
as high pressure becomes centered over the western Atlantic.

Elsewhere, surface ridging prevails across the basin anchored by
a 1030 mb high near 33N60W. A dissipating stationary front
extends from 31N29W to 30N48W. The ridge is maintaining light
winds north of 20N, with moderate to fresh trade winds south of
20N. East swell of 7 to 9 ft persists south of 20N as well E of
55W, as noted in recent altimeter satellite passes.

The stationary front will dissipate tonight, and the ridge will
shift east Monday ahead of a reinforcing cold front that will
move into the central Atlantic region Tuesday. The front will slide
east of 35W Wednesday, followed by a large area of NW swell with wave
heights of 8 to 10 ft covering much of the area north of 20N and
east of 45W Wednesday and Thursday as the swell in excess of 8 ft south of
20N subsides.

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

$$

Latto



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.