000 AXNT20 KNHC 151815 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 215 PM EDT Mon Oct 15 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...SPECIAL FEATURES... A broad area of low pressure, called a Central American Gyre, is centered over the southwestern Caribbean Sea near 15N82W. Scattered moderate to isolated strong convection is noted from 12N to 16N between 78W and 84W. There is a medium probability that a tropical cyclone may develop within this broad circulation within the next 48 hours as the system moves westward toawards Central America. Regardless of tropical cyclone development, this gyre will bring heavy rainfall across portions Central America for the next several days, including areas that have already had heavy rainfall earlier this month. This heavy rainfall will bring the potential for flash flooding and mudslides over areas of mountainous terrain. Refer to your local meteorological service for specific information on this potentially dangerous weather pattern. A cold front is presently along the Texas coast S of Houston. Scattered showers are within 90 nm of the front. Fresh to strong northerly winds behind the front will increase to minimal gale force on 17/0000 UTC. The front will then extend from SE Louisiana to the SW Bay of Campeche. Winds will diminish below gale force on 17/1200 UTC. ...TROPICAL WAVES... A tropical wave is just off the coast of W Africa along 18W from 02N-15N, moving W at 15 kt. SSMI TPW imagery shows a distinct moisture area around the wave axis. Scattered moderate convection is from 02N-08N between 14W-20W. A low amplitude tropical wave extends its axis along 47W from 01N-15N, moving west at 15-20 kt. A 700 mb trough is shown by model analyses with this wave. TPW imagery indicates abundant moisture in its environment. Scattered moderate to strong convection is occurring from 04N-11N between 44W-50W. A tropical wave extends its axis along 53W from 08N-21N, moving west at 10-15 kt. A 700 mb trough is depicted by model analyses with the wave, and there is a local maximum in TPW. It is likely that the tropical wave along 47W will be merging with this wave over the next 24 hours. Moisture associated with these waves is likely to enhance showers and thunderstorms over the Lesser Antilles Tuesday into Wednesday, and this activity will spread to the eastern Caribbean Sea during the middle of the week. A tropical wave extends its axis along 64W from 08N-21N moving west at 10 kt. Scattered moderate convection is over Puerto Rico. Scattered showers are noted over the northern Leeward Islands and Virgin Islands. This wave is expected to dissipate within 24 hours as it moves toward the central Caribbean. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the eastern Atlantic from the coast of Africa near 12N17W to 03N30W. The ITCZ extends from 03N30W to 02N45W. Besides the convection mentioned in the tropical wave section, scattered moderate convection is from 04N-08N between 20W-29W. GULF OF MEXICO... A cold front is presently along the Texas coast S of Houston. The remainder of the Gulf of Mexico has 10-15 kt SE surface flow. An upper-level high is centered over NE Mexico near 22N99W. Another upper-level high is centered over N Florida near 29N82W. Upper-level moisture is over the far W Gulf, and over the SE Gulf. Expect the cold front to move slowly SE and extend from central Florida to the NW GULF near 26N96W to the W Bay of Campeche near 21N96W on Thursday. A brief gale is forecast. See above. CARIBBEAN SEA... A tropical wave is over the E Caribbean that is forecast to dissipate in 24 hours. Two other tropical waves E of the Caribbean are forecast to merge and be just E of the Caribbean in 24 hours. See the special features section about the Cenral Caribbean Gyre. An upper level trough extends from the Mona Passage to N Colombia. Scattered showers are within 120 nm of the trough axis. ATLANTIC OCEAN... See above about the tropical waves in the tropical Atlantic. A stationary front extends across the west Atlantic from 32N56W to 29N64W to 30N70W. A surface trough continues W to 29N78W to 31N80W. Scattered showers are within 90 nm of the front and trough. A 1026 mb high is centered over the W Atlantic near 38N66W. Another 1025 mb high is centered over the E Atlantic near 33N33W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa