000 AXNT20 KNHC 260004 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 804 PM 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... A surface trough extends from 24N45W, to a 1010 mb low pressure center that is near 22N48W, to 16N58W. Scattered moderate and isolated strong rainshowers are east and northeast of the low from 20N-25N between 39W-48W. Shower activity has become more concentrated during the past several hours. The low is expected to move generally northward over the next couple of days into an area where environmental conditions are forecast to be conducive for further development, and a tropical or subtropical storm is expected to form by early this weekend. After that time, 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 cyclone 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 40W/41W from 12N southward moving west around 5 kt. Scattered showers and isolated thunderstorms associated with the wave are located from 02N-10N between 37W-44W. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea- Bissau near 12N16W and continues to 08N16W. The ITCZ begins near 08N16W, curving to 06N20W to 07N38W. The ITCZ resumes west of a tropical wave near 06N42W and continues to 05N50W. East of 17W, scattered moderate and isolated strong convection is noted from 02N-12N including over Guinea. Between 17W-50W, scattered showers and thunderstorms are occurring from 02N-09N. GULF OF MEXICO... A 1008 mb surface low is located a short distance north of Baton Rouge Louisiana. A cold front extends SW from the low to 29N92W to 21N97W. A warm front extends SE from the low to the Mississippi coast to 29N84W. Scattered moderate convection is noted from 24N- 27N between 90W-94W. Isolated showers extend southwestward from there along the front. Scattered showers and isolated thunderstorms are over the NE Gulf north of 26N east of 90W. The low pressure system over Louisiana will move E-NE across the Gulf coast states through Fri night, dragging a cold front across much of the Gulf basin. The front will be nearly stationary from central Cuba to the SW Gulf by Sat night. Another cold front will cross the eastern two-thirds of the Gulf basin beginning Sun night. CARIBBEAN SEA... Broad middle level to upper level anticyclonic wind flow spans the western and central Caribbean Sea. The monsoon trough is along 09N from 75W in northern Colombia to western Panama and southern Costa Rica. Scattered showers and thunderstorms are seen over the southwest Caribbean south of 15N and west of 78W. Scattered showers and thunderstorms are also over northern Colombia and northwestern Venezuela, and could affect the waters near South America south of 12N between 67W-78W over the next few hours. Some enhanced rainfall is possible through Friday in the SW Caribbean Sea and in 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 the Yucatan Channel Sat night and Sun. Fresh to locally strong trade winds are expected over the south-central Caribbean Sat night and Sun. ATLANTIC OCEAN... An upper level trough has been digging southeastward through the Atlantic Ocean with cyclonic upper-level flow north of 20N between 50W-65W. A cold front passes through 32N58W to 28N64W to 27N72W. The front becomes stationary from 27N72W to 29N80W. A surface trough is along 32N54W 26N58W 21N66W 22N73W, reaching the SE Bahamas. A second surface trough extends from 23N77W to 28N79W, in the NW Bahamas. Scattered moderate to isolated strong rainshowers are north of 22N between 48W-58W. Scattered showers and thunderstorms are also moving eastward off the east coast of northern Florida. 24-hour rainfall totals that are listed for the period that ended at 25/1200 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are 0.96 in Bermuda. Upper level cyclonic wind flow covers the eastern Atlantic Ocean north of 25N east of 30W. A surface trough extends from a 1010 mb low pressure center that is near 32N23W, to 28N23W, to 25N26W. Scattered moderate rainshowers cover the area that is from 29N northward and east of 24W. Isolated showers also are from 10N to 20N between Africa and 41W. The current frontal boundary that is along 28N east of Florida will transition to a warm front this evening ahead of a developing low pressure system. E to SE winds will increase E of Florida tonight and on Friday, as the low moves into Georgia. A trailing cold front from the low pressure center will reach from 31N75W into the NW Bahamas on Saturday, then stall and weaken from 31N69W to central Cuba on Sunday. For additional information please visit http://www.hurricanes.gov/marine $$ Hagen