000 AXNT20 KNHC 200603 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 103 AM EST SUN NOV 20 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. ...SPECIAL FEATURES... A 1006 mb low pressure center is in the SW corner of the Caribbean Sea near 11N81W, off the coasts of Panama, Costa Rica, and Nicaragua. Convective precipitation: Numerous strong is in northern land areas of Colombia and Venezuela, and in the coastal waters of those countries, from 10N to 13N between 70W and 75W. Widely scattered moderate to isolated strong is from 12N southward from 76W westward. Overall environmental conditions are marginally conducive for development into a tropical cyclone. It is possible that a tropical depression may form during the next few days, as the low pressure center moves slowly and erratically. The chance of formation into a tropical cyclone during the next 48 hours is medium. Gulf of Mexico Gale Warning: A cold front is along 28N83W 23N94W 19N96W. Expect gale-force NW-to-N winds and sea heights ranging from 10 feet to 16 feet, to the south of 21N to the west of 95W...including along the coast of Veracruz in Mexico. Convective precipitation: isolated moderate from 23N southward from 93W westward. Rainshowers are possible also within 90 nm on either side of the line that passes through 29N80W 26N85W 24N90W 23N93W. Please read the High Seas Forecast product under AWIPS/WMO headers HSFAT2/AXNT20 KNHC for more details. ...THE ITCZ/THE MONSOON TROUGH... The Monsoon Trough reaches the coastal areas of Senegal near 14N17W to 10N22W. The ITCZ continues from 10N22W to 05N30W 10N38W 11N41W 10N46W. Convective precipitation: scattered strong from 07N to 09N between 22W and 27W. Rainshowers are possible elsewhere from 10N southward from 60W eastward. ...DISCUSSION... ...THE REST OF THE GULF OF MEXICO... Surface anticyclonic wind flow has been spreading across the rest of the area that is to the north of the advancing cold front. The information about the cold front and gale-force winds is in the SPECIAL FEATURES section. Gale-force winds are blowing in the Gulf of Tehuantepec on the eastern Pacific Ocean side of southern Mexico. Please read the Eastern Pacific Ocean HIGH SEAS FORECAST...MIAHSFEP2/FZPN03 KNHC...and the Eastern Pacific Ocean TROPICAL WEATHER DISCUSSION...MIATWDEP/AXPZ20 KNHC...for more details. ...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: KGHB 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... from TEXAS to ALABAMA: VFR/no ceilings. FLORIDA: MVFR in Sarasota. ...FROM THE ATLANTIC OCEAN INTO THE CARIBBEAN SEA... A deep layer trough passes through the area that is about 300 nm to the east of Bermuda, ending near a point that is about 500 nm to the SE of Bermuda. A secondary upper level trough passes through the area that is about 420 nm to the W of Bermuda, across the Bahamas, to NW Cuba, and into the NW corner of the Caribbean Sea. The trough that is to the east and southeast of Bermuda supports a cold front that passes through 32N55W to 27N57W to 22N61W. A stationary front continues from 22N61W, across NW Puerto Rico, to 16N71W in the Caribbean Sea. The stationary front is dissipating from 16N71W to 15N80W, to the east central coast of Nicaragua. Convective precipitation in the Atlantic Ocean: widely scattered moderate to isolated strong from 22N northward between 50W and 60W. Isolated moderate from 18N to 22N between 59W and 70W. Convective precipitation in the Caribbean Sea: widely scattered moderate to isolated strong from 13N to 19N between 66W and 84W. ...THE REST OF THE CARIBBEAN SEA... Upper level SW wind flow covers the area to the east of the line that runs from SE Cuba, into the Gulf of Honduras. An upper level ridge runs from NW Venezuela/N Colombia, to 20N81W. The 24-HOUR rainfall totals in inches for the period ending at 20/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...is 0.02 in Guadeloupe, and 0.02 in Merida in Mexico. ...HISPANIOLA... Upper level SW wind flow is moving across the entire area. Please refer to the section with the title FROM THE ATLANTIC OCEAN INTO THE CARIBBEAN SEA for more details. An upper level trough passes through the Atlantic Ocean, across NW Cuba, into the NW corner of the Caribbean Sea. A stationary front cuts across NW Puerto Rico, and across the central sections of the Caribbean Sea. Convective precipitation: rainshowers are possible across the island, and in the coastal waters/coastal areas. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti, at 20/0200 UTC: VFR/no ceiling. few cumulonimbus clouds. for the DOMINICAN REPUBLIC: Barahona, at 20/0000 UTC: VFR. few cumulonimbus clouds. Santo Domingo: light rain. La Romana: VFR/no ceiling. few cumulonimbus clouds. Punta Cana: light rain. Santiago: MVFR. ceiling at 1600 feet. Puerto Plata: MVFR. ceiling at 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. The GFS MODEL forecast for 500 MB shows that SW wind flow will move across the area during the first 30 hours to 36 hours of the next 48 hour forecast period. A ridge will be in the SE corner of the Caribbean Sea. A trough will be approaching from the west. The trough reaches Haiti, spreading cyclonic wind flow across the western half of the island, and S wind flow elsewhere for the rest of the forecast period. The GFS MODEL forecast for 700 mb shows that anticyclonic wind flow will move across the area during the first 30 hours or so of the 48-hour forecast period. NE wind flow will continue for the rest of the forecast period. ...THE REST OF THE ATLANTIC OCEAN... An upper level trough is along 31N26W, to a 22N40W cyclonic circulation center, to 15N41W and 10N47W. A surface trough is along 40W from 19N to 24N. A second surface trough is along 38W/39W from 12N to 16N. Convective precipitation: isolated moderate from 20N to 29N between 30W and 43W. Rainshowers are possible also from 10N northward between 20W and 50W. Widely scattered to scattered moderate and isolated strong remainder of area from 10N to 26N between Africa and 30W. Surface anticyclonic wind flow covers the area from 25N northward between Africa and 50W. For additional information please visit http://www.hurricanes.gov/marine $$ MT