Tropical Weather Discussion
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000
AXNT20 KNHC 121159
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
659 AM EST Thu Jan 12 2017

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
1115 UTC.

...SPECIAL FEATURES...

...Atlantic Ocean Gale Warning...

A cold front extends from a 1009 mb low pressure center that is
near 26N56W, to 20N54W, and then a frontal trough to 16N61W.
N-to-NE gale-force winds, and sea heights ranging from 16 feet to
22 feet, are present from 26N to 31N between between 57W and 62W.
These conditions are forecast to last for another 12 hours or so.

...Caribbean Sea Gale Warning...

A shear line is along 16N61W to 15N71W. NE gale-force winds, and
sea heights ranging from 11 feet to 14 feet, are present from
from 10.5N to 13N between 74W and 78W. These conditions are
forecast to last for another 12 hours or so.

Please read the HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...and
the OFFSHORE FORECAST...MIAOFFNT3/FZNT23 KNHC...for more details.

...THE MONSOON TROUGH/THE ITCZ...

The Monsoon Trough passes through coastal border area of Guinea
and Sierra Leone, to 07N17W and 06N21W. The ITCZ continues from
06N21W to 05N26W 03N28W 02N36W and 01N41W. Convective
precipitation: isolated moderate to locally strong from 03N
southward between 06W and 12W, and from 04N southward between 27W
and 52W in NE Brazil near its border with French Guiana.

...DISCUSSION...

...THE GULF OF MEXICO...

Middle level to upper level anticyclonic wind flow covers the Gulf
of Mexico from 93W eastward. Middle level to upper level westerly
wind flow is moving from Texas to Florida, across the coastal
waters of the U.S.A. in the Gulf of Mexico. The westerly wind flow
merges with the anticyclonic wind flow from 93W eastward.

Upper level anticyclonic wind flow is in Mexico from 23N
southward, moving into the SW corner of the Gulf of Mexico.

Comparatively drier air in subsidence is apparent in water vapor
imagery, in much of the Gulf of Mexico, except for the SW corner
of the area, and in the coastal waters from south central
Louisiana to 27N along the Texas coast.

A surface ridge cuts across the Gulf of Mexico, along a NE-to-SW
line.

...LOW LEVEL CLOUD CEILINGS AND WEATHER FOR THE OFFSHORE OIL
PLATFORM SITES THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N
NORTHWARD AND FROM 88W WESTWARD...

LIFR: none.

IFR: none.

MVFR: KVAF and KGHB.

LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF
THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA...

TEXAS: MVFR in McAllen, from Hebbronville to the NAS in Corpus
Christi. IFR in Rockport. MVFR in Victoria/Port Lavaca/Palacios,
in Pearland, Tomball, and Conroe. LOUISIANA: LIFR in parts of the
Lake Charles metropolitan area. MVFR in Lafayette. IFR in
Boothville. LIFR in Hammond, and at the Lakefront Airport of New
Orleans on the southern side of Lake Pontchartrain. MISSISSIPPI:
LIFR in the Hattiesburg metropolitan area. MVFR in Natchez. IFR
in McComb. LIFR in Gulfport and Pascagoula. ALABAMA: MVFR in the
Mobile metropolitan area. LIFR in Evergreen. MVFR in the Mobile
metropolitan area. FLORIDA: drizzle in Mary Esther. MVFR in
Destin and Perry. LIFR in Cross City, and at the Tampa Executive
Airport.

...THE CARIBBEAN SEA...

Middle level-to-lower level anticyclonic wind flow, from 600 mb
to 800 mb, is moving across Hispaniola and Puerto Rico, into the
central sections of the Caribbean Sea, and to Central America. SE
wind flow covers Central America from Nicaragua to the Yucatan
Peninsula of Mexico. Middle level-to-upper level NE-to-E wind
flow is moving across Cuba and across the NW corner of the
Caribbean Sea.

Upper level SW wind flow is curving anticyclonically across the
Caribbean Sea between 60W and Nicaragua. Middle level-to-upper
level anticyclonic wind flow covers the area from 67W westward.
Middle level to upper level cyclonic wind flow, that is moving
toward the Atlantic Ocean 26N54W cyclonic circulation center,
covers the area from 67W eastward.

A shear line continues from 17N61W to 15N67W and 14N73W.
Convective precipitation: Rainshowers are possible within 90 nm
on either side of 16N60W 15N73W 13N80W. scattered moderate to
isolated strong is along the coast of Nicaragua from 11N to 13N
from 82W westward.

24-HOUR rainfall totals in inches for the period ending at
12/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are 0.97 in
Curacao, and 0.01 in Guadeloupe.

...HISPANIOLA...

Upper level SW wind flow is moving across the area. Middle
level-to-lower level anticyclonic wind flow, from 600 mb to
800 mb, is moving across Hispaniola and Puerto Rico. Comparatively
drier air in subsidence is apparent in water vapor imagery.

SURFACE OBSERVATIONS...for the DOMINICAN REPUBLIC: Barahona: VFR.
Santo Domingo/La Romana/Punta Cana: VFR. Santiago: VFR. earlier
rain has ended. Puerto Plata: VFR.

The GFS MODEL forecast for 250 MB shows that SW wind flow, with a
ridge, will move across the area during the next 48 hours. The
GFS MODEL forecast for 500 MB shows that NE wind flow, between a
trough to the east and a ridge to the west, will move across the
area during the next 48 hours. The GFS MODEL forecast for 700 mb
shows that NE wind flow, around a ridge, will move across
Hispaniola during the next 48 hours.

...THE ATLANTIC OCEAN...

An upper level cyclonic circulation center is near 25N52W. Upper
level cyclonic wind flow covers the area from 16N between 48W and
64W. A stationary front passes through 32N54W, to a 1009 mb low
pressure center that is near 26N56W. A slowly-moving cold front
continues from the 1009 mb low pressure center, to 25N53W 22N53W,
and to 17N61W. A shear line continues from 17N61W to 15N67W and
14N73W. Convective precipitation: widely scattered to scattered
moderate and isolated strong from 21N northward between 47W and
54W. Rainshowers are possible within 90 nm on either side of
21N50W 19N52W 16N60W 15N73W 13N80W.

An upper level trough passes through 32N36W to 29N27W to 25N22W.
Convective precipitation: isolated to widely scattered moderate
within 360 nm to the NE of the line 24N20W beyond 32N32W.

A surface ridge passes through 32N26W to 27N27W, 21N39W, and
10N48W, to the east of the 1009 mb low pressure and frontal
boundary. A surface ridge passes through 32N74W, beyond NE
Florida into the Gulf of Mexico, to the west of the 1009 mb low
pressure center and frontal boundary.

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

$$
MT



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