000 AXNT20 KNHC 280605 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 104 AM EST WED DEC 28 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...THE ITCZ/THE MONSOON TROUGH... The Monsoon Trough reaches the coastal sections of The Ivory Coast near 04N07W to 03N19W. The ITCZ continues from 03N19W to 03N40W and 02N49W. A surface trough is along 10N41W 07N48W. Convective precipitation: widely scattered moderate to isolated strong from 08N to 11N between 42W and 47W. Convective precipitation with the Monsoon Trough/ITCZ: isolated to widely scattered moderate and locally strong elsewhere from 10N southward from 60W eastward. ...DISCUSSION... ...THE GULF OF MEXICO... A surface trough is along the western edge of the Yucatan Peninsula. Convective precipitation: scattered moderate to isolated strong, weakening with time, continues from 17N to 19N between 91W and 93W. Possible lingering rainshowers are from 18N to 24N from 94W westward, in the SW corner of the area. An upper level ridge is along 96W/97W. Upper level anticyclonic wind flow covers the SW corner of the Gulf of Mexico, from 23N southward from 92W westward. Upper level NW wind flow covers the rest of the area. A 1023 mb high pressure center is near 28N84W. Surface anticyclonic wind flow covers the Gulf of Mexico from 24N northward. Convective precipitation: Rainshowers are possible from 23N to 25N between 85W and 88W, in areas of scattered/broken low level clouds. ...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: KBQX, KGLS, KEHC, and KMIS. IFR: none. MVFR: KVAF, KEIR, KSPR, KVQT, and KDLP. 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, nearly everywhere, from the Lower Rio Grande Valley to the Houston metropolitan area, and in Galveston and Beaumont/Port Arthur. IFR/MVFR elsewhere. LOUISIANA: LIFR, pretty much everywhere, in the southern sections/coastal plains. IFR/MVFR elsewhere. MISSISSIPPI: LIFR in the coastal plains/southernmost sections. IFR/MVFR from Natchez/McComb, to MVFR in Hattiesburg. ALABAMA: LIFR in the coastal plains/southernmost sections. IFR/MVFR elsewhere, from Dothan to Evergreen. FLORIDA: LIFR mostly, with IFR/MVFR elsewhere, from Cross City westward. ...THE CARIBBEAN SEA... Upper level anticyclonic wind flow spans the entire area, with a ridge that extends from northern Colombia beyond the Yucatan Channel. Comparatively drier air in subsidence is apparent in water vapor imagery, from 72W eastward. The monsoon trough is along 06N/08N between 76W and beyond 84W in Costa Rica. Convective precipitation: rainshowers are possible from 12N southward from 76W westward. 24-HOUR rainfall totals in inches for the period ending at 28/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are 0.11 in Guadeloupe, and 0.04 in Curacao. ...HISPANIOLA... Upper level W-to-NW wind flow is moving across Hispaniola. Comparatively drier air in subsidence is apparent in water vapor imagery, across the entire area. 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 Port-au-Prince in Haiti: VFR/no ceiling. for the DOMINICAN REPUBLIC: Barahona: VFR. few cumulonimbus clouds. Santo Domingo/La Romana/Punta Cana: VFR/no ceiling. Santiago/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 NW-to-SE oriented ridge is forecast to be along the line from the NW corner of the Caribbean Sea to Colombia. The GFS MODEL forecast for 500 MB shows that northerly wind flow will move across the area during the next 48 hours, with a Gulf of Mexico-to-Cuba-to-central Caribbean Sea ridge. It is possible that anticyclonic wind flow also may move across Hispaniola during the next 48 hours, with some slight variations in the orientation of the ridge. The GFS MODEL forecast for 700 mb shows that E-to-NE wind flow will move across the area during the first 36 hours of the 48-hour forecast period. The wind direction will be variable during the remaining 12 hours or so, with a possible inverted trough, and some possible anticyclonic wind flow with a ridge. ...THE ATLANTIC OCEAN... An east-central Atlantic Ocean upper level trough is supporting a cold front that passes through 32N30W to 28N32W and 24N37W. The cold front is dissipating along 24N37W 22N44W 21N50W. Convective precipitation: isolated moderate from 26N northward between 26W and 29W. Rainshowers are possible elsewhere from 20N northward between 25W and 74W. Upper level cyclonic wind flow covers the Atlantic Ocean from 10N to 20N between 40W and 60W. This is the area of cyclonic wind flow that was at the SW part of the upper level trough from 24 hours ago. Convective precipitation: isolated moderate from 28N northward between Africa and 16W. Rainshowers are possible in the area of cyclonic wind flow, in areas of scattered/broken low level clouds. Surface anticyclonic wind flow covers the Atlantic Ocean from 23N northward between 43W and 80W, to the west of the cold front. A 1029 mb high pressure center is near 33N54W. A 1023 mb high pressure center is near 29N75W. For additional information please visit http://www.hurricanes.gov/marine $$ MT