000 AXNT20 KNHC 230535 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 AM EDT Mon Oct 23 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 0515 UTC. ...SPECIAL FEATURES... A cold front across the NW Gulf extends from central Louisiana near 29N91W to Brownsville Texas. The front will sweep across the Gulf through early Tuesday with gale force northerly winds expected to develop S of 21N W of 95W later today, and persist for about 12 hours, as the pressure gradient remains strong. Please see the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...TROPICAL WAVES... A tropical wave extends from 17N49W to 06N52W, moving W at 10 kt. The wave coincides with 700 mb troughing and a maximum in 850 mb relative vorticity east of the wave axis. Scattered moderate isolated strong convection is from 08N-15N between 41W-50W, and continues to be enhanced by a mid-level trough extending from 25N40W to northern Guyana. A tropical wave is moving across Central America along 90W south of 21N, and moving W at 10-15 kt. The wave coincides with 700 mb troughing and a maximum in 850 mb relative vorticity along the wave axis. Scattered moderate convection is from 12N-20N between 80W-92W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 12N16W to 10N20W. The Intertropical Convergence Zone axis extends from 10N20W to 07N26W to 05N50W. Scattered moderate convection is from 03N-05N between 15W-19W. ...DISCUSSION... GULF OF MEXICO... A vigorous middle to upper level trough moving into the lower Mississippi River valley and supports the cold front mentioned above. A pre-frontal trough extends from SE Louisiana to near 24N93W. Low-level moisture convergence and mid-level divergence is generating scattered showers and isolated tstms across the eastern Gulf N of 25N E of 87W. The cold front is expected to sweep across the basin through Tuesday with fresh to strong northerly winds spreading eastward in wake of the front. Strong high pressure will move in the western Gulf by Wednesday night. CARIBBEAN SEA... The combination of a tropical wave along 90W, a surface trough in the Gulf of Honduras and a favorable upper level winds over much of the western Caribbean supports scattered showers and isolated tstms W of a line from the Yucatan Channel near 22N86W to northern Colombia near 11N74W...including Central America. Moderate to fresh trades prevail over most of the W Caribbean, and fresh to strong trades prevail E of 75W from the pressure gradient associated with high pressure in the western N Atlc. ...HISPANIOLA... Dry air and NW flow aloft will support fair weather across the island today. Fresh to strong trades expected to become moderate to occasionally fresh on Tuesday. ATLANTIC OCEAN... A broad surface ridge prevailing across the Atlantic N of 30N is bisected by a stationary front that extends into the discussion area from 32N45W to 28N57W. Random showers are occurring within 150 nm of the frontal boundary. The front will dissipate later today south of 30N. An upper level low is centered near 25N64W. Random showers are occurring from 22N-30N between 60W-66W in association with the upper level low. Moderate to fresh trade winds prevail elsewhere north of the convergence zone and east of the tropical wave mentioned above. For additional information please visit http://www.hurricanes.gov/marine $$ Mundell