000 AXNT20 KNHC 050520 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 120 AM EDT Sat May 5 2018 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 0500 UTC. ...SPECIAL FEATURE... An upper level cyclonic circulation center is along the Atlantic Ocean side of Cuba along 78W. Upper level cyclonic wind flow that is moving around the circulation center covers the area from SW corner of the Caribbean Sea to 28N in the Atlantic Ocean between 65W in the Atlantic Ocean and 90W in the Gulf of Mexico. A surface trough is along 74W/76W, across SE Cuba and the Bahamas, from 18N in the Windward Passage to 28N in the Atlantic Ocean. Precipitation: widely scattered moderate to isolated strong rainshoewrs cover the areas from 15N in the Caribbean Sea to 27N in the Atlantic Ocean between 70W and 78W. Rainshowers are possible elsewhere from 14N in the Caribbean Sea to 32N in the Atlantic Ocean between 60W in the Atlantic Ocean and 86W in the NW corner of the Caribbean Sea, including in parts of Florida. This feature was forecast by the computer models at the beginning of the week. The GFS model forecast, for 250 mb and 500 mb, shows that a cyclonic circulation center will stay on top of Cuba, weaken into a trough, and then move eastward. An upper level trough will move across the Gulf of Mexico toward Florida. The GFS model, from the surface to 700 mb, shows that a trough will move westward from its present position on top of Cuba and the Bahamas, to Florida, for the next few days. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea- Bissau near 12N16W to 04N21W. The ITCZ continues from 04N21W to the Equator along 25W, to 03S33W to 01S44W. Precipitation: scattered moderate to strong from 05N to 07N between 16W and 18W. rainshowers are possible elsewhere from 08N southward. ...DISCUSSION... GULF OF MEXICO... A cold front is in the coastal plains of Texas, set to enter the NW corner of the Gulf of Mexico shortly. A NW-to-SE oriented trough spans Mexico and parts of Central America to Nicaragua. Precipitation: widely scattered moderate to scattered moderate to strong rainshowers are in Mexico from 17N to 25N between 97W and 101W. Broken to overcast multilayered convective debris clouds cover the Gulf of Mexico from 22N northward from 90W westward. The current Texas cold front will enter the NW Gulf today, and then dissipate along the coasts of Louisiana and Texas by Saturday night. Gentle to moderate N to NE winds will prevail elsewhere through Tuesday night. CARIBBEAN SEA... Please read the SPECIAL FEATURES section for more infomation about the upper level cyclonic circulation and surface trough near Cuba and the Bahamas. Fresh easterly winds will prevail in the eastern Caribbean Sea and in the Tropical North Atlantic Ocean through Sunday night. The upper level cyclonic circulation center is on top of Cuba. Expect widespread rainshowers with thunder N of 15N between 70W and 80W through Sunday night. The winds and seas will subside gradually on Monday and Tuesday. ATLANTIC OCEAN... Please read the SPECIAL FEATURES section for more infomation about the upper level cyclonic circulation and surface trough near Cuba and the Bahamas. Surface anticyclonic wind flow covers the Atlantic Ocean from 10N northward from 70W eastward. A 1028 mb high pressure center is near 32N55W. The current surface trough, the subject of the SPECIAL FEATURE section, will drift westward and amplify on Saturday, as it interacts with the upper level cyclonic circulation center. The trough will move over southern Florida during the day on Saturday. Widespread rainshowers, some with embedded thunder, fresh to strong winds, and building seas are expected in the vicinity of the trough through Sunday night. For additional information please visit http://www.hurricanes.gov/marine $$ MT