000 AXNT20 KNHC 251147 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 647 AM EST SUN DEC 25 2016 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. ...THE ITCZ/THE MONSOON TROUGH... The Monsoon Trough reaches the coastal sections of Sierra Leone near 07N12W, to 05N17W. The ITCZ continues from 05N17W to 03N32W and 03N40W. Convective precipitation: widely scattered moderate to isolated strong, mostly, from 02N to 10N between 20W and 60W. High level clouds are to the south of 22N17W 20N40W 16N60W, moving northeastward. ...DISCUSSION... ...THE GULF OF MEXICO... Upper level anticyclonic wind flow spans the area. Comparatively drier air in subsidence is apparent in water vapor imagery, across the entire Gulf of Mexico. A surface ridge extends from the NE corner of the Gulf of Mexico into the SW corner of the area, near 19N96W in the coastal plains of Mexico. A surface trough is along 91W/92W from 15N in western sections of Guatemala to 25N in the Gulf of Mexico. Convective precipitation: isolated moderate from 22N to 25N between 90W and 93W. Rainshowers are possible elsewhere from 22N southward into the Isthmus of Tehuantepec between 90W and 96W. isolated moderate also is from 22N to 27N between 86W and 90W. ...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: KBBF, KXIH, KHHV, KVAF, KEMK, KGUL, KEHC, and KGHB. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: MVFR from south to north, with smaller areas of LIFR/IFR. light rain in Huntsville. LOUISIANA: LIFR in Lake Charles. LIFR from Baton Rouge, and surrounding Lake Pontchartrain. LIFR in Patterson, Galliano, Port Fourchon, and in Boothville. IFR in Lafayette. MVFR in New Iberia. MISSISSIPPI: mostly LIFR from Natchez-to-Hattiesburg southward to the coast. ALABAMA: LIFR from Evergreen southward. MVFR in Fort Rucker. FLORIDA: LIFR from Crestview to Milton and southwestward to the NAS in Pensacola. light rain in Milton. IFR in Cross City and the Tampa Executive Airport. LIFR in Punta Gorda. ...THE CARIBBEAN SEA... Upper level SW wind flow is to the south of 15N60W 16N70W 15N80W 12N84W. Upper level easterly wind flow covers the rest of the Caribbean Sea. An upper level trough passes through 17N60W to 15N66W 16N70W. Convective precipitation: isolated moderate from 18N southward from 76W eastward. Upper level southerly wind flow covers the area that is from 15N to 20N between 80W and 85W. Convective precipitation: scattered moderate to isolated strong from 11N to 17N between 79W and 85W, including the coastal plains and coastal waters of Nicaragua and Honduras. It is possible that speed convergence may be a contributing factor to the precipitation. Upper level southerly wind flow is from Honduras northward from 85W westward to land. Middle level to upper level cyclonic wind flow is in the NW corner of the Caribbean Sea, toward the Yucatan Peninsula. Convective precipitation: isolated moderate is in Belize and its coastal waters. 24-HOUR rainfall totals in inches for the period ending at 25/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are 0.20 in Guadeloupe, and 0.07 in Curacao. ...HISPANIOLA... Upper level NE wind flow is moving across Hispaniola. Convective precipitation: Rainshowers are possible across Hispaniola, and in the coastal waters and coastal plains, in areas of broken low level to middle level clouds. SURFACE OBSERVATIONS...for the DOMINICAN REPUBLIC: Santo Domingo/La Romana/Punta Cana: VFR/no ceiling. Santiago and Puerto Plata: VFR/no ceiling. The GFS MODEL forecast for 250 MB shows that NW wind flow will move across the area during the next 48 hours. A trough will move from the SE Bahamas to the E and SE of Hispaniola. A ridge will cut across SE Cuba, giving the rest of the NE wind flow. The GFS MODEL forecast for 500 MB shows that NE wind flow will move across the area during the next 48 hours. A ridge will extend from the Bahamas beyond SE Cuba. The second half of day one will consist of some E-to-SE wind flow, followed by NE wind flow during all of day two. The GFS MODEL forecast for 700 mb shows that anticyclonic wind flow will move across the area during the first half of day one. NE wind flow will move across the area during the rest of the 48-hour forecast period. A NW-to-SE oriented ridge will extend from the Atlantic Ocean, off the coast of NE Florida, beyond Hispaniola. ...THE ATLANTIC OCEAN... A surface trough extends from the Upper Florida Keys to South Carolina near 34N79W. Convective precipitation: LIFR conditions, mist, and light rain are being reported from the Jacksonville Florida metropolitan area, into coastal Georgia and SE South Carolina. A central Atlantic Ocean upper level trough is supporting a stationary front that passes through 32N43W to 27N57W. A dissipating stationary front continues from 27N57W to 25N64W. Convective precipitation: Rainshowers are possible to the W and NW of the frontal boundary. An upper level cyclonic circulation center is near 28N25W. A second upper level cyclonic circulation center is near the Canary Islands near 28N18W. Cyclonic wind flow covers the area that is from 19N northward from 40W eastward. A surface trough is along 25W/26W from 21N to 29N. Convective precipitation: isolated moderate from 20N northward between 20W and 30W. widely scattered moderate to isolated strong from 28N northward between Africa and 20W. Broad surface anticyclonic wind flow is from 24N northward, to the W and NW of the stationary front, and to the east of the Florida- to-South Carolina surface trough. For additional information please visit http://www.hurricanes.gov/marine $$ MT