000 AXNT20 KNHC 251205 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 804 AM EDT Thu Oct 25 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 0600 UTC surface analysis and satellite imagery through 1130 UTC. ...SPECIAL FEATURES... A surface trough is along 24N46W, to a 1009 mb low pressure center that is near 21N48W, to 17N56W. The broad area of surface low pressure and cyclonic wind flow is becoming better defined, gradually. The surrounding precipation pattern is showing signs of organization. Widely scattered to scattered moderate and isolated strong rainshowers are within 380 nm of the 1009 mb low pressure center in the NE quadrant. The expected movement of the low pressure center is northward during the next few days, into an area where the environmental conditions are forecast to be conducive for more development. It is likely that a tropical storm or a subtropical storm may form by early this weekend. The system is forecast to turn westward well to the north or northeast of the Lesser Antilles through early next week. The chance of formation into a tropical cyclonie during the next 48 hours is high. Please refer to the TROPICAL WEATHER OUTLOOK, MIATWOAT/ABNT20 KNHC, for more details. ...TROPICAL WAVES... An Atlantic tropical wave is along 41W/42W from 12N southward. Isolated moderate rainshowers are from 10N southward between 40W and 46W. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 10N14W, to 07N16W. The ITCZ continues from 07N16W, to 05N22W and 07N39W, and from 06N44W to 06N54W near the NW coast of French Guiana. Disorganized widely scattered moderate to isolated strong rainshowers are within 180 nm on either side of the line that runs from 03N at the Prime Meridian, to 03N06W 03N19W, 04N25W 05N31W 07N41W. Isolated moderate rainshowers are elsewhere from 13N southward between 40W and 60W. GULF OF MEXICO... A dissipating stationary front extends from Marco Island Florida to 27N89W. A warm front extends from that point to a 1010 mb low just off the coast of Texas near 28N96W. A stationary front extends southward from the low to 23N96W. National Weather Service Doppler Radar indicates scattered to numerous showers and thunderstorms are along the Texas and western Louisiana coasts from Houston to Lake Charles and extending inland. Scattered showers and isolated thunderstorms extend offshore of Texas and Louisiana north of 28N. An upper level cyclonic circulation center is over the southern Gulf of Mexico near 19N92W. Upper level cyclonic wind flow covers the area that is from 22N southward between 89W and 96W. GOES-16 water vapor channels indicate relatively dry air over the southwest Gulf, and mostly clear to partly cloudy skies are present. The current 1011 mb low pressure system, that is centered along the Texas coast near Galveston, will drift NE into Louisiana this morning, then move E-NE across the Gulf coast states through Friday. It will drag a cold front across the Gulf. The front will be nearly stationary from central Cuba to the SW Gulf on Saturday night. CARIBBEAN SEA... The monsoon trough over the far southwest Caribbean extends along 10N west of 75W from the N coast of Colombia to Costa Rica and into the East Pacific. The monsoon trough combined with an area of weak upper-level diffluence in the SW corner of the Caribbean Sea is enhancing scattered showers and isolated thunderstorms from 08N-13N between 75W-84W. Scattered moderate to isolated strong convection has been increasing during the last few hours over N Colombia and NW Venezuela from 07N-11N between 70W-78W. Aside from the southwest Caribbean, the remainder of the Caribbean is free of significant convection at this time. Some enhanced rainfall is possible through the remainder of the work week over the southwest Caribbean and the southern half of Central America from Nicaragua southward due to an active monsoon trough in the region. Gentle to moderate trades will prevail across the Caribbean Sea through Sat. A cold front crossing the Gulf of Mexico will become stationary across Yucatan Channel Sat night and Sun. Fresh trade winds are expected over the south-central Caribbean early next week. ATLANTIC OCEAN... A cold front enters the forecast area at 32N70W and extends SW to 29N79W to the east coast of central Florida. At 03Z, the front was changed to a stationary front west of 76W. A N-S surface trough is also analyzed from 28N79W southward through the NW Bahamas to 24N77W. A 1010 mb low is located near 29N61W with a cold front extending SW from there to the central Bahamas. This front has weakened and will likely be dropped and changed to a trough for the upcoming 06Z map. Scattered to numerous showers are north of 24N between 54W-64W. Isolated showers with abundant cloud clover are from 22N-26N between 64W-74W. Scattered to broken low clouds are along the front east of northern Florida. A 1008 mb low near 34N25W extends scattered moderate convection north of 29N between 18W-25W. A weakening stationary front over NW waters will transition to a warm front later today ahead of a developing low pressure system. SE winds will increase E of Florida tonight and Fri as the low moves into Georgia. A trailing cold front from the low will reach from Bermuda into the NW Bahamas Sat, then stall and weaken from 30N70W to central Cuba on Sun. 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