000 AXNT20 KNHC 150007 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 807 PM EDT Sun Oct 14 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... A broad 1009 mb low, associated with a Central American Gyre, is centered over the southwestern Caribbean Sea near 15N80W. The monsoon trough extends NE from the low to 16N77W. The monsoon trough extends W from the low to NE Nicaragua to Honduras to Guatemala. Scattered moderate convection prevails over the W Caribbean from 11N-16N between 75W-82W. This activity is enhanced by an area of upper-level anticyclonic flow over the same area. Satellite imagery shows numerous moderate scattered strong convection over northeastern Costa Rica, much of Nicaragua and central Honduras. Scattered thunderstorms are noted over southern Guatemala and the Mexican state of Chiapas. This broad low pressure system is moving slowly west-northwestward, and some gradual development is possible before it moves inland over Central America Monday night or Tuesday. Regardless of development, locally heavy rainfall, which could cause flash flooding, is possible across portions of Central America for much of the week. In addition to the potential for heavy rain over Central America, these rains could spread to the Yucatan Peninsula and portions of southern Mexico this week. ...TROPICAL WAVES... A low amplitude tropical wave extends its axis along 43W from 01N-12N, 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 07N-13N between 42W-47W. A tropical wave extends its axis along 51W from 08N-21N, moving west around 15 kt. A 700 mb trough is depicted by model analyses with the wave, and there is a local maximum in TPW. Numerous moderate to strong convection is noted from 16N-18N between 48W- 52W. Scattered showers are noted from 19N-22N between 46W-50W and along the wave's axis south of 13N. Moisture with this tropical wave is likely to enhance showers and thunderstorms over the Lesser Antilles Tuesday into Wednesday. The waves along 43W and 51W will enhance showers and thunderstorms over the eastern Caribbean sea during the middle of this week. A tropical wave extends its axis along 61W from 08N-21N. Isolated showers are noted over the northern Windward and southern Leeward Islands. Additional scattered moderate convection is seen from 08N-13N between 57W-59W. The northern end of the wave will be moving into an area of diffluent flow after tonight. Enhanced showers and thunderstorms are possible tonight for the Leeward Islands and Virgin Islands, spreading to Puerto Rico on Monday. This wave is expected to weaken as it moves toward the central Caribbean. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the eastern Atlantic from the coast of Africa near 12N16W and extends to 08N29W. The ITCZ extends from 08N29W to 09N40W. Aside from the convection related to the tropical waves described above, no other significant convection is currently seen on satellite imagery with the monsoon trough or ITCZ. GULF OF MEXICO... A dissipating stationary front extends from 24N84W to 26N81W. A surface ridge prevails across the remainder of the basin anchored by a 1023 mb high centered over Central Virginia near 38N78W. With this, dry air prevails across most of the basin. The remnants of the front will lift north tonight.The next cold front is expected to enter the far NW Gulf by Tuesday morning. This front will stall from S central Louisiana to the western Gulf along 96W through Thu night. Strong to near gale force northerly winds are likely behind that front starting Tue night. Showers and thunderstorms will become likely over the far NW Gulf on Monday ahead of this front. CARIBBEAN SEA... Three tropical waves will affect the Lesser Antilles over the next few days. See the Tropical Waves section for more details. See Special Features section for information relating to the broad low in the western Caribbean Elsewhere, scattered moderate to strong convection is occurring on the northwest coast of Venezuela from 10N-12N between 68W-74W. Scattered showers prevail between 68W-70W between the eastern Dominican Republic and the coast of Venezuela. ATLANTIC OCEAN... Three tropical waves are in the Tropical Atlantic between the Lesser Antilles and the coast of Africa. See the Tropical Waves section above for details. A cold front extends across the west Atlantic from 32N62W to 30N66W, where it becomes a stationary front. The stationary front extends from that point to 29N73W, where it becomes a dissipating stationary front. The dissipating stationary front extends from that point to near Everglades City, Florida. Isolated showers and thunderstorms prevail over portions of South Florida near the front. To the southeast, a surface trough is analyzed over the southeast Bahamas. Scattered showers and thunderstorms are east of the trough from 19N-23N between 65W-70W, enhanced by a diffluent flow aloft. Farther east, a cold front the coast of Morocco near 31N10W to 31N14W. A 1024 mb high is centered near 33N37W, leading to relatively quiet weather elsewhere. For additional information please visit http://www.hurricanes.gov/marine $$ ERA/Hagen