000 AXNT20 KNHC 191102 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 702 AM EDT Fri May 19 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 1045 UTC. ...SPECIAL FEATURES... Please refer to the METEO-FRANCE High Seas Forecast, that is listed on the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO- MARINE/BULLETIN/GRANDLARGE/METAREA2. Gale-force winds are forecast for the area that is called: AGADIR. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 51W/52W from 10N southward, moving westward 15 knots. Convective precipitation: isolated moderate from 10N southward between 43W and 53W. A Caribbean Sea tropical wave is along 67W/68W from 12N southward into Venezuela, moving westward 10 to 15 knots. Convective precipitation: widely scattered moderate to isolated strong from 04N to 06N between 63W and 66W, inland. isolated moderate elsewhere in Venezuela from 04N to 10N from 64W westward. A Caribbean Sea tropical wave is along 82W from 17N southward, moving westward 10 knots. This wave is moving through the area of an upper level trough, whose cyclonic wind flow covers the Caribbean Sea from 80W westward. Convective precipitation: any precipitation is in the area of the larger-scale cyclonic wind flow that accompanies the upper level trough. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through coastal sections of Senegal near 15N17W, to 12N20W, and 06N28W. The ITCZ continues from 06N28W to 01N38W. Convective precipitation: scattered strong from 04N to 06N between 22W and 26W. Widely scattered moderate to isolated strong from 05N to 07N between 30W and 35W. Isolated moderate elsewhere from 10N southward from 60W eastward. ...DISCUSSION... ...THE GULF OF MEXICO... Upper level westerly wind flow spans the area. Some of the wind flow that is in the NW corner is from the SW. Some of the wind flow that is in the central part of the Gulf of Mexico from west to east is NW, hinting at some anticyclonic wind flow, in the central and NE sections. High level moisture is within 120 nm on either side of a line from the Florida Panhandle, into the central Gulf waters, to the Mexico coast near 24N. A surface ridge extends from the NW corner of the area toward the SW corner of the Gulf of Mexico. ...VISIBILITY IN MILES, AND WEATHER, FOR THE OFFSHORE OIL PLATFORM SITES, THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N NORTHWARD AND FROM 88W WESTWARD... KMZG, KBBF, and KVOA: 2 to 3, and mist. KXIH, KEMK, KHQI, KVQT, KGRY, KEIR, and KMDJ: 3 TO 5 and mist. KVOA: 3 to 5 and haze. VISIBILITY IN MILES, AND WEATHER, FOR THE COASTAL PLAINS OF THE U.S.A., FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... ALABAMA: 4 and mist in Evergreen. FLORIDA: Cross City: 5 and mist. ...THE CARIBBEAN SEA... An upper level trough remains from NW Cuba, to a 19N82W NW Caribbean Sea cyclonic circulation center, to southern Nicaragua/ Costa Rica. Upper level anticyclonic wind flow covers the rest of the Caribbean Sea that is to the east of the persistent trough. A surface trough is along 85W/86W from 16N at the coast of Honduras to 25N in the SE Gulf of Mexico. Convective precipitation: isolated moderate between 77W and 84W. Broken to overcast multilayered clouds and other possible rainshowers cover the Caribbean Sea from 13N to 20N between 60W and 80W. Please monitor any advisories and bulletins from local meteorology offices, emergency management services, and other governmental agencies. ...HISPANIOLA... Upper level anticyclonic wind flow is moving across Hispaniola. The persistent upper-level trough, that has been situated in the NW Caribbean Sea during the last several days, has falling apart with time. The southern part of the trough has been filling and drifting westward. The deep convective precipitation has been weakening and dissipating. Some drying between 800 mb and 500 mb was noted on the 18/1200 UTC Santo Domingo rawinsonde, suggesting that some dry air has been making its way into Hispaniola and Haiti. It appears that the heavy rainfall threat may be shifting to Jamaica and the NW Caribbean Sea during the next 24 hours or so, per the NWP model guidance and recent trends, Please monitor advisories and bulletins from local meteorology offices, emergency management services, and other governmental agencies. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: MVFR. for the DOMINICAN REPUBLIC: Barahona: VFR. few cumulonimbus clouds. Santo Domingo: VFR. La Romana and Punta Cana: VFR. Santiago and Puerto Plata: VFR. The GFS MODEL forecast for 250 mb shows that SW wind flow will shift to westerly, and then to NW by the end of the first 24 hours of the 48-hour forecast period. Expect NW wind flow during day two. The GFS MODEL forecast for 500 mb shows that SW wind flow will last for the first 6 hours to 12 hours, with an E-to-W oriented Atlantic Ocean-to-Caribbean Sea ridge. Cyclonic wind flow will move across Hispaniola for the next 30 hours, with an Atlantic Ocean-to-Hispaniola trough. Anticyclonic wind flow starts to push out of the way the cyclonic wind flow, from north-to-south across Hispaniola, with an Atlantic Ocean-to-Hispaniola ridge, during the 6 hours to 12 hours of the forecast period. The GFS MODEL forecast for 700 mb shows that Hispaniola will be on the western side of an Atlantic Ocean anticyclonic circulation center during the next 48 hours. Expect mostly SE wind flow, with a bit of E wind flow, during the forecast period. ...THE REST OF THE ATLANTIC OCEAN... An upper level trough passes through 32N33W, to 28N40W and 21N44W. A cold front passes through 32N45W to 31N47W. Convective precipitation: broken to overcast multilayered clouds and possible rainshowers cover the area from 20N to 30N between 30W and 60W, and from 20N to 26N between 60W and 80W. A surface ridge extends from a 1028 mb high pressure center that is near 41N20W through 32N33W, to 28N47W. A 1023 mb high pressure center is near 32N54W. A second 1023 mb high pressure center is near 32N60W. Surface anticyclonic wind flow covers the Atlantic Ocean from 16N northward between 50W and 80W. For additional information please visit http://www.hurricanes.gov/marine $$ MT