000 AXNT20 KNHC 281153 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 653 AM EST Sat Jan 28 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... ...GALE WARNING FOR THE GULF OF MEXICO... The 06-hour forecast consists of a first cold front that is going to merge with a second cold front, along 23N84W 22N96W 19N95W. Expect N-to-NE gale-force winds, and sea heights ranging from 8 feet to 13 feet, from 22N to 25N to the W of the cold front. Please read the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through Sierra Leone near 07N12W to 03N23W. The ITCZ continues from 03N23W to 02N31W and 01N38W. Convective precipitation: Widely scattered moderate to isolated strong from 06N southward. ...DISCUSSION... ...THE GULF OF MEXICO... Upper level Westerly wind flow is moving across the area. Anticyclonic wind flow from 600 mb to 800 mb also covers the Gulf of Mexico. Comparatively drier air, in subsidence, is apparent in water vapor imagery, from 27N southward. A cold front passes through the Straits of Florida near 24N80W, along the NW coast of Cuba, to 22N87W. A stationary front continues from 22N87W to a 1014 mb low pressure center that is near 22N94W. The stationary front continues from the 1014 mb low pressure center, to 18N94W, and then it curves northwestward in Mexico to 22N97W. The coastal observations for the stations that are in the coastal plains of Mexico, from the Yucatan Peninsula westward to Tampico and Ciudad Victoria, show a mixture of conditions of some LIFR, some MVFR/VFR, and some drizzle/mist. Rainshowers are possible in the Gulf of Mexico from 90W westward. A surface ridge is along 25N84W, to SE Louisiana, beyond central Texas. ...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: KMZG and KBBF. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: VFR/MVFR and light rain in the Lower Rio Grande Valley area. light rain from Robstown to Corpus Christi to Rockport. drizzle in Port Lavaca. from LOUISIANA to FLORIDA: VFR. ...THE CARIBBEAN SEA... Upper level SW wind flow is covering the Caribbean Sea to the east of the line that runs from the Peninsula de la Guajira of northern Colombia beyond 18N63W. Middle level-to-upper level anticyclonic wind flow covers the entire Caribbean Sea, from the eastern section, into the central Caribbean Sea, and then beyond the NW corner of the area. Comparatively drier air, in subsidence, is apparent in water vapor imagery, across the entire area. No significant 24-HOUR rainfall amounts have been reported, for the period ending at 28/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC. ...HISPANIOLA... Middle level-to-upper level NE wind flow is moving across Hispaniola. Comparatively drier air in subsidence is apparent in water vapor imagery, across the entire area. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: VFR. for the DOMINICAN REPUBLIC: Santo Domingo: VFR. La Romana and Punta Cana: MVFR. ceiling 1600 feet in each city. Santiago/Puerto Plata: VFR. The GFS MODEL forecast for 250 MB shows that an upper level cyclonic circulation center will be to the south of Puerto Rico. Northerly wind flow is forecast to move across Hispaniola during day one. Expect N-to-NW wind flow during day two. The cyclonic circulation center will open into a trough on top of the islands that are immediately to the east of Puerto Rico. The GFS MODEL forecast for 500 MB shows that SE wind flow will move across the area during day one. A ridge will move across the area during day two, bringing anticyclonic wind flow to Hispaniola. The GFS MODEL forecast for 700 mb shows that anticyclonic wind flow will move across Hispaniola at the start of the 48-hour forecast. Expect SE wind flow during the rest of the forecast time, except for more anticyclonic wind flow at the end of the 48-hour forecast period. ...THE ATLANTIC OCEAN... A cold front passes through 32N66W, to 25N77W between Eleuthera and Nassau in the Bahamas, beyond the NW coastal waters of Cuba. Upper level W and SW wind flow is moving on top of the area of the cold front. The wind flow eventually becomes anticyclonic more downstream, toward the SE. Convective precipitation: rainshowers are possible to the NW of the line that passes through 21N75W, 25N60W, beyond 33N45W. A deep layer trough is about 950 nm to the west of Africa. The trough supports a cold front that passes through 32N30W to 25N35W, to 21N44W. A dissipating stationary front continues from 21N44W to 19N55W. Convective precipitation: isolated moderate from 30N northward between 24W and 28W. Rainshowers are possible elsewhere within 90 nm on either side of the line from 30N29W to 25N36W 20N44W, and from 12N to 20N between 43W and 60W. A surface ridge, that is to the east of the frontal boundary, extends from a 1026 mb high pressure center that is near 34N13W, to 23N29W, to 16N40W. A surface ridge, that is to the west of the frontal boundary, passes through 32N38W, to a 1024 mb high pressure center that is near 27N51W, 22N61W, to Cuba near 22N80W. For additional information please visit http://www.hurricanes.gov/marine $$ MT