000 AXNT20 KNHC 061149 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 648 AM EST Mon Mar 6 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... ...CARIBBEAN SEA GALE WARNING... The conditions starting at 06/0600 UTC: NE-to-E gale-force winds, and sea heights ranging from 11 feet to 14 feet, in the coastal waters of Colombia, from 10.5N to 13N between 73W and 77W. ALSO: NE gale-force winds, and sea heights ranging from 8 feet to 11 feet, to the N of 18N between 73W and 76W, including in the Windward Passage. NE-to-E gale-force winds, and sea heights ranging from 8 feet to 11 feet, to the N of 16N between 70W and 73W. NE-to-E gale-force winds, and sea heights ranging from 10 feet to 13 feet, to the N of 19N between 78W and 83W. Please read the latest NWS High Seas Forecast under the AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ATLANTIC OCEAN GALE WARNING... The conditions starting at 06/0600 UTC: A cold front is along 31N45W 27N50W 18N63W. NE-to-E gale-force winds and sea heights ranging from 8 feet to 11 feet, to the W of a line from 25N80W to 21N69W. Please read the latest NWS High Seas Forecast under the AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...GULF OF MEXICO GALE WARNING... The conditions starting at 06/0600 UTC: E gale-force winds, and sea heights ranging from 10 feet to 13 feet, from 23N to 25N to the E of 85W, including in the Straits of Florida. Please read the latest NWS High Seas Forecast under the AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through the coastal sections of Sierra Leone near 08N13W to 05N14W 04N16W. The ITCZ continues from 04N16W to 01N30W, and to the Equator along 41W. Convective precipitation: Isolated moderate to locally strong from 07N southward from 60W eastward. ...DISCUSSION... ...THE GULF OF MEXICO... A middle level to upper level trough is moving from the east central sections of the Gulf of Mexico to Florida. Scattered to broken multilayered clouds and possible rainshowers are from 90W eastward. A surface ridge extends from north central Florida into the SW corner of the area. ...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: KMZG and KGRY. MVFR: KBBF, KBQX, KXIH, KHHV, KVAF, KGUL, KHQI, KEHC, KVQT, KGHB, KATP, KEIR, KMDJ, and KVOA. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: IFR/MVFR in the Lower Valley/the Deep South, and in Rockport. IFR/LIFR from Laredo into the middle Texas coastal plains. light rain in Victoria. IFR/MVFR from Victoria to Port Lavaca to Palacios. IFR/MVFR from Bay City to the Houston metropolitan area and surrounding smaller communities, to Huntsville. MVFR from Beaumont/Port Arthur to Jasper and light rain. LOUISIANA: MVFR from Baton Rouge southward and southwestward. MISSISSIPPI: MVFR in Natchez. ALABAMA: VFR. FLORIDA: MVFR in Valparaiso. ...THE CARIBBEAN SEA... Upper level SW wind flow covers the area to the east of the line that runs from the SE coast of Nicaragua to SW Haiti. Upper level anticyclonic wind flow is moving across the area that is to the west of the aforementioned Nicaragua-to-Haiti line. NE wind flow from 600 mb to 800 mb spans the entire area. Rainshowers are possible, in areas of broken low level clouds, mainly from 70W eastward, and from 15N northward from 70W westward. The 24-hour rainfall amounts, for the period ending at 06/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are: 0.20 in Guadeloupe. ...HISPANIOLA... NE-to-E wind flow from 600 mb to 800 mb is moving across the area. NE wind flow from 350 mb to 500 mb approaches the NE corner of Hispaniola. NW wind flow from 350 mb to 500 mb moves across Cuba toward Haiti. Rainshowers are possible inland and in the coastal waters. Comparatively drier air in subsidence is apparent in water vapor imagery across Hispaniola. SURFACE OBSERVATIONS...for the DOMINICAN REPUBLIC: Santo Domingo/La Romana/Punta Cana: VFR. earlier light rain in Santo Domingo ended an hour ago. Santiago: moderate rain. MVFR. ceiling 1200 feet. Puerto Plato: MVFR. ceiling 1600 feet. The GFS MODEL forecast for 250 MB shows that SW wind flow will move across the area during the next 48 hours, with a ridge from the SW corner of the Caribbean Sea toward the NW corner of the Caribbean Sea. The GFS MODEL forecast for 500 MB shows that the wind flow will be from the NW, first with a W-to-E oriented ridge, and then later just with NW wind flow, for the rest of day one. Expect more NW wind flow for the first 12 to 18 hours of day two. Expect anticyclonic wind flow during the last 6 hours to 12 hours of day two, with an Atlantic Ocean to Hispaniola E-to-W oriented ridge. The GFS MODEL forecast for 700 mb shows that an anticyclonic circulation center moves from a position that is just to the E of the SE Bahamas to a position that is to the NE of Puerto Rico during the first 24 hours of the 48=hour forecast period. Expect NE to E to SE wind flow during day one. The anticyclonic circulation re-organizes itself and it remains quasi- stationary to the north of the Mona Passage for the first 12 to 18 hours or so of day two. Expect anticyclonic wind flow across Hispaniola during this time. Expect NE wind flow for the last half of day two. ...THE ATLANTIC OCEAN... Deep layer cyclonic wind flow, with a trough, covers the area from 20N northward from 40W westward. A cold front passes through 32N44W to 27N50W 21N60W, across Hispaniola, to 19N77W between SE Cuba and Jamaica. Convective precipitation: rainshowers are possible to the north and northwest of the line that passes through 32N40W to 25N50W, to 16N63W in the Caribbean Sea, and to 15N83W. An upper level trough extends from a 25N25W cyclonic circulation center, to 15N39W and 10N40W. Convective precipitation: rainshowers are possible from 20N to 30N between 20W and 30W. A surface ridge passes through 32N28W to 24N39W and 20N56W. A second surface ridge is along 23N61W 28N71W beyond 32N75W. For additional information please visit http://www.hurricanes.gov/marine $$ MT