000 AXNT20 KNHC 120605 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 105 AM EST Sun Nov 12 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 0000 UTC surface analysis and satellite imagery through 0545 UTC. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 11N15W to 10N17W. The Intertropical Convergence Zone axis extends from 10N17W to 07N33W to 05N43W to 06N49W. Scattered moderate convection is from 03N-14N between 20W-40W. A surface trough is west of the ITCZ extending from 13N47W to 06N51W supporting scattered moderate convection E of its axis from 08N-13N between 40W-50W. ...DISCUSSION... GULF OF MEXICO... Strong high pressure anchored over Vermont extends SSW across the SE CONUS and then across the Gulf waters. A weakness in the ridge is analyzed as a surface trough from SE Louisiana coastal waters near 29N89W to 24N89W, which is generating isolated showers within 75 nm either side of its axis. A tight pressure gradient between the strong ridge and lower pressure over the SW N Atlc and the W Caribbean supports fresh to locally strong ENE winds E of the surface trough, the Yucatan Channel and the Florida Straits. Moderate NE to E winds are elsewhere. Otherwise, water vapor imagery indicate broad upper troughing over the basin along with relatively dry air aloft, which is maintaining generally fair weather conditions. The surface trough will continue to move W towards the NW Gulf through Sunday afternoon and then dissipates. Fresh to locally strong winds will prevail across the eastern half of the basin through Tuesday. CARIBBEAN SEA... Broad low pressure prevails across the Caribbean focused on a 1006 mb low centered off the coast of Nicaragua near 12N82W. A surface trough extends from 16N85W to the low center to 11N82W. Water vapor imagery indicate the surface low and troughing is supported aloft by a mid-level low stretching from the Windward Passage to the SW Caribbean. In addition, a favorable diffluent environment remains over the western and central Caribbean, which is supporting scattered showers and tstms N of 13N W of 75W and across Hispaniola. A middle-level low N of the Mona Passage supports a cluster of showers and tstms that extends to the Passage and across northern Puerto Rico. A strong pressure gradient between high pressure N of the area and the broad area of low pressure in the western half of the Caribbean supports fresh to strong winds in the NW Caribbean N of 18N W of 80W. The synoptic pattern aloft will continue in place through Monday as the upper level troughing over the Gulf of Mexico and SW North Atlc will be slow to weaken into early next week. Otherwise, moderate to occasional fresh trades E of 75W will persist. ...HISPANIOLA... Scattered showers and isolated tstms continue across the island tonight as a favorable middle to upper level diffluent environment prevails. Upper level troughing is expected to persist to the NW over the SE Gulf of Mexico and SW North Atlc through Sunday night with persistent convection expected across the island, adjacent coastal waters and much of the north-central Caribbean Sea. Potential hazards of localized flooding and life-threatening mud slides are possible, especially if stronger convection develops during peak daytime heating and instability Sunday and Monday. ATLANTIC OCEAN... A stationary front extends across the SW North Atlc from 30N65W SW to 27N74W then to the Florida coast near 26N80W. A middle-level low N of the Mona Passage supports a cluster of showers and tstms S of 21N between 63W-70W. To the east, a surface trough extends from 29N57W to 22N57W with widely scattered showers and isolated tstms within 120 nm either side of its axis. The surface trough remains within the southern periphery of a surface ridge anchored by a 1035 mb high centered NE of the Azores. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos