000 AXNT20 KNHC 271107 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 707 AM EDT Mon Mar 27 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 ATLANTIC OCEAN... The current synoptic analysis consists of: a surface trough from 29N66W, to a 1008 mb low pressure center that is near 24N69W, to 20N70W. Expect NE-to-E gale-force winds and sea heights ranging from 13 feet to 18 feet, within 30 NM on either side of the line from 28N63W to 27N68W to 26N69.5W. Please read the latest High Seas Forecast product under AWIPS/WMO headers HSFAT2/FZNT02 KNHC for more details. Please refer to the METEO-FRANCE High Seas Forecast, that is listed on the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO- MARINE/BULLETIN/GRANDLARGE/METAREA2. The OUTLOOK, for the 24 hours that follow the forecast that is valid until 28/1200 UTC, consists of: the threat or persistence of SW near gale or gale in IRVING. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through the coastal sections of Sierra Leone near 07N12W, curving to 04N13W. The ITCZ continues from 04N13W, to 01N21W, curving to the Equator along 31W, to 02S40W, near the coast of Brazil. Convective precipitation: scattered moderate to strong from 01N to 03N between 14W and 17W, from 03N southward between 20W and 36W, and from 04N southward between 38W and 43W. ...DISCUSSION... ...THE GULF OF MEXICO... An upper level ridge is moving from the central sections of the Gulf of Mexico into the eastern half of the area. It is spreading upper level anticyclonic wind flow everywhere in the Gulf of Mexico. An upper level cyclonic circulation center and trough are in the central sections of the U.S.A. The southernmost part of the trough has moved into the extreme NW corner of the Gulf of Mexico, near the upper Texas Gulf coast and SW Louisiana. The convective precipitation that has been in Texas, moving with the trough, has weakened and dissipated in the upper Texas Gulf coastal plains. A surface ridge passes through 32N78W in the Atlantic Ocean, across NE Florida, into the Yucatan Peninsula of Mexico. ...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: KBBF and KBQX. MVFR: KMZG, KXIH, KVAF, KEMK, KHQI, KVQT, KEIR, KGRY, 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: LIFR from Hebbronville into parts of the middle Texas Gulf coastal plains, with some IFR also. MVFR from Victoria to the Houston metropolitan area and surrounding smaller communities and to Conroe, and from Galveston to Beaumont/Port Arthur and Jasper. LOUISIANA: MVFR in the SW and south central coastal sections, to the south of Baton Rouge, and in parts of the SE coastal plains. MISSISSIPPI: MVFR, some IFR, from Natchez-Hattiesburg southward. ALABAMA: LIFR in Dothan. IFR/MVFR from Ft. Rucker westward and southwestward, between Florida and Mississippi. FLORIDA: LIFR/IFR from Tallahassee westward, into the Florida Panhandle. MVFR at the Tampa Executive Airport. IFR in Punta Gorda. ...FROM THE WESTERN ATLANTIC OCEAN INTO THE CARIBBEAN SEA... An upper level trough passes through 32N75W to 23N71W to Jamaica, to 16N81W, to southern Nicaragua. A surface ridge passes through 32N78W in the Atlantic Ocean, across NE Florida, into the Yucatan Peninsula of Mexico. A surface trough is along 29N66W, to a 1009 mb low pressure center that is near 24N69W, to central sections of the Dominican Republic, to 19N70W at the coast of the Dominican Republic. Convective precipitation: Broken to overcast multilayered clouds and isolated moderate from 22N northward between 55W and 72W. Rainshowers are possible elsewhere from 18N to 22N between 60W and 70W. ...THE REST OF THE CARIBBEAN SEA... The dividing line of wind flow regimes is the Atlantic Ocean 23N71W-to-Nicaragua upper level trough. Upper level SW wind flow covers everywhere that is to the east of the trough. Upper level NW wind flow is to the NW of the trough. No 24-hour rainfall totals are listed for the period that ended at 27/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC. ...HISPANIOLA... Middle level-to-upper level SW wind flow is moving across the island. Rainshowers are possible inland, and in the coastal waters. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: MVFR for visibility. for the DOMINICAN REPUBLIC: Barahona: VFR. Santo Domingo: VFR. La Romana: VFR. Punta Cana: VFR. Santiago: IFR for visibility. mist. Puerto Plata: VFR. The GFS MODEL forecast for 250 mb shows that SW wind flow will move across the area during the next 48 hours. A ridge will extend from Colombia to 10N95W in the eastern Pacific Ocean. The GFS MODEL forecast for 500 mb, and for 700 mb, shows that SW wind flow will be moving across the area, with a trough to the W and NW of the area. The wind flow will become SW-to-W, as a second trough moves into the Windward Passage at the end of the 48-hour forecast period. ...THE REST OF THE ATLANTIC OCEAN... An upper level trough passes through 32N15W to 22N23W and 10N25W. A dissipating cold front passes through 32N27W to 30N30W and 28N36W. Convective precipitation: rainshowers are possible from 17N to 24N between Africa and 30W. Surface anticyclonic wind flow covers the area that is from 10N to 29N between Africa and the dissipating cold front. A 1021 mb high pressure center is near 28N24W. Surface anticyclonic wind flow covers the area that is from 30N northward between 42W and the SE coast of the U.S.A. For additional information please visit http://www.hurricanes.gov/marine $$ MT