AXNT20 KNHC 081145
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
705 AM EST THU DEC 8 2016
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
...GALE-FORCE WINDS ARE FORECAST FOR THE GULF OF MEXICO...
The 06-hour forecast and the 12-hour forecast consist of a cold
front and N-to-NE winds 20 to 30 knots with frequent gusts to
gale-force, and sea heights eventually building to 8 feet to 12
feet during that time period. The 18-hour forecast consists of a
cold front from 29N83W to 25N92W to 24N95W to 19N96W. Expect
gale-force winds, NW-to-N, and sea heights ranging from 10 feet
to 14 feet, to the south of 27N to the west of 94W and to the
west of the cold front. Please read the HIGH SEAS FORECAST...
MIAHSFAT2/FZNT02 KNHC...for more details.
...THE ITCZ/THE MONSOON TROUGH...
The Monsoon Trough reaches the southern coastal sections of
Sierra Leone, to 06N16W. The ITCZ continues from 06N16W to
03N27W and 02N37W. Convective precipitation: isolated moderate
to locally strong within 180 nm on either side of 10N60W 06N50W
03N40W 04N31W 04N12W, to 03N at the Prime Meridian.
...FROM THE WESTERN ATLANTIC OCEAN INTO THE GULF OF MEXICO,
INCLUDING THE REST OF THE GULF OF MEXICO...
Upper level SW wind flow spans the Gulf of Mexico. A cold front
passes through 32N58W in the Atlantic Ocean, to 28N67W and
26N76W near the NW Bahamas. The front becomes stationary from
the NW Bahamas, across the southern part of Florida, into the
south central Gulf of Mexico, and 22N95W. A second stationary
front passes through the Florida Big Bend, to the north central
Gulf of Mexico, beyond the deep south of Texas, and curving
northwestward into northern Mexico. Convective precipitation:
isolated moderate from 23N to 27N. rainshowers are possible
elsewhere across the area.
The 24-hour forecast for the Gulf of Tehuantepec, that is on the
southern side and Eastern Pacific Ocean side of Mexico, consists
of a GALE warning. Please read the Eastern Pacific Ocean HIGH
SEAS FORECAST...MIAHSFEP2/FZPN03 KNHC...and the Eastern Pacific
Ocean TROPICAL WEATHER DISCUSSION...MIATWDEP/AXPZ20 KNHC...for
...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...
MVFR: KBBF, KBQX, KXIH, KHHV, KVBS, KEMK, KHQI, KGUL, KEHC,
LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF
THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA...
TEXAS: LIFR in Brownsville, Port Isabel, Harlingen, and Weslaco.
IFR in Edinburg and McAllen. rain in Laredo and Hebbronville.
IFR in Falfurrias and at the NAS in Kingsville. MVFR in Alice
and Robstown. MVFR in the Corpus Christi metropolitan area with
light rain. MVFR from Victoria to Port Lavaca and Palacios. MVFR
in Bay City, in Galveston, and in Angleton/Lake Jackson with
light rain. light rain and IFR at the Houston Hobby Airport, at
Ellington Field, and at the Houston Intercontinental Airport.
MVFR in Sugar Land and Pearland. MVFR in Tomball and Huntsville.
IFR and light rain in Conroe. MVFR in Beaumont/Port Arthur. IFR
and mist in Jasper. LOUISIANA: IFR/MVFR in the Lake Charles
metropolitan area. MVFR and light rain in New Iberia. IFR in
Lafayette. MVFR in Patterson, Galliano, in Port Fourchon, in
Baton Rouge with light rain, and around Lake Pontchartrain.
MISSISSIPPI: MVFR from Natchez and Hattiesburg southward, with
light rain in McComb. ALABAMA: MVFR in Birmingham. FLORIDA:
mist in Cross City. LIFR at the Tampa Executive Airport.
...THE CARIBBEAN SEA...
An upper level trough was along 21N61W to 16N67W, to the
Peninsula de la Guajira of NE Colombia. Upper level cyclonic
wind flow covers the area from 18N southward between 71W and
Central America. Upper level NE wind flow covers the area from
Honduras northward from 80W westward. Upper level SW wind flow
is in the extreme NW corner of the Caribbean Sea.
A surface trough is along 60W/61W from 17N to Venezuela.
Convective precipitation: widely scattered moderate to isolated
strong from Venezuela and Trinidad to 17N between 60W and 67W,
and from 12N to 14N between 54W and 58W.
Rainshowers are possible, elsewhere, in areas of broken low
level clouds, across much of the area.
A surface ridge extends from an Atlantic Ocean 1020 mb high
pressure center, that is near 25N61W, across the Bahamas to
The monsoon trough is along 09N/10N from northern Colombia
beyond southern Costa Rica, into the eastern Pacific Ocean.
Convective precipitation: scattered strong from 11N southward
from 80W eastward. Isolated moderate to locally strong from 13N
southward from 80W westward.
The 24-HOUR rainfall total in inches for the period ending at
08/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...is 0.06 in
Upper level NE wind flow is moving across the island.
Comparatively drier air in subsidence is apparent in water vapor
imagery, across the area. Convective precipitation: Rainshowers
are possible across Hispaniola, and in the coastal waters and
coastal plains, in areas of broken low level to middle level
SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: VFR/no
ceiling. for the DOMINICAN REPUBLIC: Barahona: VFR/no ceiling.
Santo Domingo/La Romana/Punta Cana: VFR/no ceiling.
Santiago: LIFR for fog all quadrants. ceiling at 1200 feet.
Puerto Plata: MVFR. ceiling at 1600 feet.
The GFS MODEL forecast for 250 MB shows that an anticyclonic
circulation center will be in the NW corner of the Caribbean Sea
and a cyclonic circulation center will be in the SE corner of
the Caribbean Sea, moving toward Hispaniola, and reaching
Hispaniola at the end of day one/the beginning of day two.
The cyclonic circulation center weakens eventually, giving SW
wind flow to Hispaniola. The ridge that was in the NW corner of
the Caribbean Sea moves eastward, to the south of Jamaica. The
GFS MODEL forecast for 500 MB shows that an E-to-W oriented
Atlantic Ocean ridge will be just to the north of Hispaniola
during the next two days. The wind flow across Hispaniola will
be from the E-to-NE during day one, and SE wind flow during day
two. The GFS MODEL forecast for 700 mb shows that an E-to-W
oriented Atlantic Ocean ridge will be just to the north of
Hispaniola during the next two days. Expect SE wind flow, during
the next two days, along with some possible inverted troughs.
...THE REST OF THE ATLANTIC OCEAN...
The upper level trough that was supporting a cold front during
the last few days has moved northward, and out of the area that
is covered by this summary. A cold front passes through 32N28W
to 28N38W and 29N48W. Convective precipitation: rainshowers are
possible from 22N northward from 50W eastward.
A surface ridge passes through 32N15W, across the Canary Islands
to 25N23W, to 23N40W, to the 1020 mb high pressure center that
is near 25N61W, and then across the Bahamas, to Cuba.
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