000 AXNT20 KNHC 311148 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 648 AM EST Tue Jan 31 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-FORCE WINDS IN THE CARIBBEAN SEA... The 21-hour forecast, for the forecast that was issued starting at 31/0600 UTC, consists of NE gale-force winds and sea heights ranging from 9 feet to 12 feet from 10.5N to 13N between 74W and 77W. A localized strong pressure gradient is expected to develop during the late night and early morning hours of Wednesday, in the SW Caribbean Sea in the coastal waters of Colombia. 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 08N13W to 07N14W. The ITCZ continues from 07N14W to 01N25W. Convective precipitation: widely scattered moderate to isolated strong from 04N southward from 09W eastward, from 04N to 05N between 15W and 17W, and from 04N southward between from 34W westward. ...DISCUSSION... ...FROM THE WESTERN ATLANTIC OCEAN...ACROSS THE BAHAMAS...INTO THE GULF OF MEXICO...AND INCLUDING THE REST OF THE GULF OF MEXICO... Upper level W wind flow spans the entire Gulf of Mexico. Upper level SW wind flow covers the Atlantic Ocean to the NW of the line that passes through 32N60W to 21N75W. A cold front passes through 32N64W in the Atlantic Ocean, to 28N70W, across Andros Island in the Bahamas, to 22N85W in the Yucatan Channel. Rainshowers are possible within 240 nm to 360 nm to the NW of the line that passes through 32N58W 27N66W 21N75W. A 1026 mb high pressure center is near 26N87W in the east-central sections of the Gulf of Mexico. Surface anticyclonic wind flow covers the Gulf of Mexico from 23N northward. A ridge is along 30N77W in the Atlantic Ocean, to 27N82W in Florida, to the 1026 mb high pressure center, to the Texas/Mexico coastal border. A surface ridge also extends from the 1026 mb high pressure center that is near 20N97W in the coastal plains of Mexico, to the Isthmus of Tehuantepec of southern Mexico. Gale-force winds are forecast to continue for the next 24 hours or so, in the Gulf of Tehuantepec, on the eastern Pacific Ocean side of southern Mexico. Please read the EASTERN PACIFIC OCEAN HIGH SEAS FORECAST, MIAHSFEP2/FZPN03 KNHC, and the EASTERN PACIFIC OCEAN TROPICAL WEATHER DISCUSSION, MIATWDEP/AXPZ20 KNHC, for more details. ...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: KEHC and KIKT. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: the corridor from Palacios to Bay City to Angleton/Lake Jackson, and Beaumont/Port Arthur covers the conditions from MVFR to LIFR to IFR and IFR/MVFR. LOUISIANA: LIFR and light rain from Lake Charles to New Iberia and Patterson. from MISSISSIPPI to FLORIDA: VFR. ...FROM THE WEST-CENTRAL ATLANTIC OCEAN INTO THE CARIBBEAN SEA... INCLUDING THE REST OF THE CARIBBEAN SEA... A slowly-moving cold front passes through 31N61W, to 23N70W, across the SE Bahamas near 22N70W, across SE Cuba, to 19N80W in NW corner of the Caribbean Sea, to the north central part of Nicaragua. Rainshowers are possible from 14N northward from 80W westward. Middle level-to-upper level cyclonic wind flow covers the Caribbean Sea from a 16N82W cyclonic circulation center, to a SE Hispaniola cyclonic circulation center. Upper level SE wind flow covers the area that is between 60W and Puerto Rico. Comparatively drier air, in subsidence, is apparent in water vapor imagery, across the entire Caribbean Sea. 24-HOUR rainfall amounts in inches, for the period ending at 31/0000 UTC, according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES, MIATPTPAN/SXCA01 KNHC, 0.02 in Guadeloupe. ...HISPANIOLA... Cyclonic wind flow, from 350 mb to 800 mb, is moving across Hispaniola, with a trough. 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: Barahona: VFR. Santo Domingo/La Romana/Punta Cana: VFR. Santiago/Puerto Plata: VFR. The GFS MODEL forecast for 250 MB shows that NW-becoming-W wind flow will move across Hispaniola during day one of the 48-hour forecast period. An upper level trough will continue to move eastward away from Puerto Rico. Day two will consist of W-to-SW wind flow, as a ridge develops across the area. The GFS MODEL forecast for 500 MB shows that anticyclonic wind flow from a ridge will span the area during the next 48 hours. The GFS MODEL forecast for 700 mb shows that an inverted trough will cover the area during day one. Day two will consist of E-to-SE wind flow. ..THE REST OF THE ATLANTIC OCEAN... A deep layer trough extends from Mauritania, to just to the north of the Cabo Verde Islands, to 16N30W and 11N43W. Comparatively drier air in subsidence is apparent in water vapor imagery within 370 nm to the north of 15N from 30W eastward, and within 500 nm to 600 nm to the north of 10N between 30W and 50W. An upper level anticyclonic circulation center is near 26N44W. A 1030 mb high pressure center is near 29N38W. A surface ridge passes through 32N22W, to a 1028 mb high pressure center that is near 29N36W, 26N51W, and to 24N64W. For additional information please visit http://www.hurricanes.gov/marine $$ MT