000 AXNT20 KNHC 120605 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 204 AM EDT Thu Sep 12 2019 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 0530 UTC. ...SPECIAL FEATURES... A surface trough extends from the Atlantic Ocean, about 200 nm to the N of the SE Bahamas, to SE Cuba and Jamaica. Scattered moderate to strong rainshowers are from 23N to 26N between 66W and 70W, from 21N to 23N between 70W and 72W, and from 21N to 23N between 73W and 75W. The second and third areas of rainshowers are on top of and/or just to the east of the SE Bahamas. Atmospheric conditions are forecast to become a little more conducive for tropical cyclone formation during the weekend. It is likely that a tropical depression may form, as the system moves slowly toward the west-northwest, across the Florida Straits and southeastern Florida, and into the eastern Gulf of Mexico. It is likely that this disturbance may produce periods of locally heavy rainfall and gusty winds across the Bahamas through Friday, and across Florida during the weekend. An Air Force Reserve reconnaissance aircraft is scheduled to investigate the system on Thursday afternoon, if necessary. The chance of tropical cyclone formation during the next 48 hours is medium. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 26W, passing through the western section of the Cabo Verde Islands, from 20N southward. The wave is moving W 10 knots. Widely scattered moderate to isolated strong rainshowers are near the monsoon trough, from 04N to 15N from 33W eastward to Africa. This wave is forecast to move westward, quickly, during the next several days. Some development is possible during the weekend, or early next week, while the tropical wave moves through the tropical Atlantic Ocean. An Atlantic Ocean tropical wave is along 39W/40W, from 19N southward, moving W 10 to 15 knots. Widely scattered moderate to isolated strong rainshowers are from 06N to 16N between 35W and 41W. An Atlantic Ocean tropical wave is along 52W/53W, from 20N southward, moving W 10 knots. A 1010 mb low pressure center is along the wave near 14N. Widely scattered moderate to isolated strong rainshowers are from 12N to 17N between 51W and 59W. This system is forecast to move westward, toward unfavorable upper level winds, and tropical cyclone formation is not anticipated. A Caribbean Sea tropical wave is along 72W/73W, from 17N southward, moving W 15 knots. Scattered to numerous strong rainshowers, in clusters, is in northern sections of Colombia. A western Caribbean Sea tropical wave is along 86W/87W, from 18N southward, moving W 10 knots. The wave passes through Honduras and Nicaragua. Isolated moderate rainshowers are from 17N northward from 80W westward, with the upper level cyclonic wind flow. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Senegal near 14N17W, to 10N30W, to 12N39W, and 13N52W, and to 12N56W. Much of the precipitation that is in the area of the monsoon trough also is close to the tropical waves. GULF OF MEXICO... The upper level cyclonic circulation center, that was in SE Georgia/NE Florida nearly 24 hours ago, now is in the NE corner of the Gulf of Mexico. Upper level cyclonic wind flow covers the Gulf of Mexico to the north of the line that runs from the central coast of Louisiana through the Yucatan Channel. Isolated moderate to locally strong rainshowers are from 24N northward between the west coast of Florida and 86W. Upper level cyclonic wind flow continues from East Texas into southern interior sections of Mexico, including in the coastal waters from Texas into the SW corner of the Gulf of Mexico. Widely scattered moderate to isolated strong rainshowers are in the Gulf of Mexico from 27N southward from 90W westward. Numerous strong rainshowers are in the Isthmus of Tehuantepec of southern Mexico. Broad surface anticyclonic wind flow spans the Gulf of Mexico. A surface ridge extends from a northern Alabama 1021 mb high pressure center, through SE Louisiana, into the SW corner of the Gulf of Mexico. High pressure, centered N of the basin, will support moderate to fresh NE to E winds into the weekend. Weak low pressure in the SW corner of the Gulf of Mexico will remain nearly stationary. A trough of low pressure, possibly as a tropical cyclone, will move W from Florida into the eastern Gulf of Mexico from this weekend into early next week, accompanied by widespread rainshowers, thunderstorms, gusty winds and building seas. CARIBBEAN SEA... Isolated moderate rainshowers are from 17N northward from 75W westward, in an overall area of multiple smaller areas of cyclonic wind flow. Part of the precipitation that is in the NW corner is related to the NE Gulf of Mexico upper level cyclonic circulation center. Another part of the precipitation is related to the surface trough that is reaching SE Cuba and Jamaica. The monsoon trough is along 08N/09N, between 75W in Colombia and beyond southern Costa Rica, into the eastern Pacific Ocean. Scattered moderate to strong rainshowers are in the coastal plains and coastal waters of Colombia, on the Pacific Ocean side of Colombia, and especially from 07N to 10N between 77W and 80W, near the border of Colombia and Panama. High pressure, centered N of the region, will maintain moderate trade winds, that will at times pulse to fresh to strong in the S central Caribbean Sea. A tropical wave will cross from the central Caribbean Sea into the western Caribbean Sea on Friday. A strong tropical wave will approach the tropical N Atlantic Ocean and the eastern Caribbean Sea during the time from the weekend into early next week. This feature also will bring widespread showers and thunderstorms, gusty winds and building seas. ATLANTIC OCEAN... An upper level trough extends from a 34N46W cyclonic circulation center, to a 30N51W cyclonic circulation, to a 19N56W cyclonic circulation center, across the NE Caribbean Sea to a 16N74W central Caribbean Sea cyclonic circulation center, toward Costa Rica. Another surface trough is over the central Atlantic from 28N49W to 20N56W. Widely scattered moderate convection is within 180 nm of the trough axis. In the far E Atlantic, northerly strong to near gale force winds are expected off the coast of Morocco through Thu. A trough of low pressure, from the SE Bahamas to eastern Cuba, will move WNW slowly, through the end of the week. It is possible that the feature may become a tropical cyclone, reaching the Florida Peninsula late on Friday, accompanied by widespread showers, thunderstorms, gusty winds and building seas. High pressure will weaken slowly, and move northward in advance of this trough. A strong tropical wave may approach the waters S of 22N, by the end of the weekend into early next week. $$ MT