000 AXNT20 KNHC 130604 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 204 AM EDT Fri Sep 13 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 0500 UTC. ...SPECIAL FEATURES... The center of Potential Tropical Cyclone Nine, at 13/0300 UTC, is near 23.8N 74.8W. This position also is about 280 nm/520 km to the southeast of Freeport in Grand Bahama Island, and about 210 nm/390 km to the southeast of Great Abaco Island, in the Bahamas. The feature is moving NW, or 310 degrees, 2 knots. The estimated minimum central pressure is 1009 mb. The maximum sustained wind speeds are 25 knots with gusts to 35 knots. Scattered moderate to strong rainshowers, in individual clusters, are within 360 nm of the center in the NE quadrant. The disturbance has been meandering in the southeastern Bahamas. The system is expected to move slowly northwestward on Friday, and continue that motion through the weekend. It is anticipated to move across the central and northwestern Bahamas on Friday, and along or over the east coast of Florida on Saturday. The disturbance is forecast to become a tropical depression or a tropical storm during the next day or so. The chance of tropical cyclone formation during the next 48 hours is high. Please, read the latest NHC forecast/ advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC, or go to the website hurricanes.gov, for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 33W, from 20N southward, moving W 10 to 15 knots. Isolated moderate to locally strong rainshowers are within 330 nm of the wave in the W semicircle. The atmospheric conditions are expected to become more conducive for development in a couple days. It is possible that a tropical depression may form early next week, while the system moves quickly westward across the tropical Atlantic Ocean. An Atlantic Ocean tropical wave is along 42W/43W, from 20N southward, moving W 10 to 15 knots. Isolated moderate to locally strong rainshowers are within 330 nm of the wave in the W semicircle, mostly from 16N southward. An Atlantic Ocean tropical wave is along 57W, from 20N southward, moving W 10 knots. Scattered moderate to strong rainshowers are within 100 nm to the east of the wave, and within 80 nm to the west of the wave, from 14N to 16N. A Caribbean Sea tropical wave is along 78W/79W, from 19N southward, moving W 15 knots. Precipitation also is near the monsoon trough, in the SW corner of the Caribbean Sea. A tropical wave is moving through Central America, along 89W, from 18N in Guatemala southward, moving W 10 knots. Isolated moderate to locally strong rainshowers are in western sections of Honduras, and in Mexico and Guatemala between the tropical wave and the Isthmus of Tehuantepec. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through Senegal near 14N17W to 08N26W, to 08N36W, to 07N43W. Widely scattered moderate to isolated strong rainshowers are within 210 nm on either side of the monsoon trough. GULF OF MEXICO... An upper level cyclonic circulation center is in the east central Gulf of Mexico. Upper level cyclonic wind flow covers at least the northern half of the Gulf of Mexico. Isolated moderate rainshowers cover the Gulf of Mexico from 24N northward, especially within 210 nm to the west of the west coast of Florida. An upper level cyclonic circulation center is in interior southern Mexico. Isolated moderate rainshowers are in the SW corner of the Gulf of Mexico, from 24N southward from 90W westward. High pressure in the SE U.S.A. will support moderate to fresh NE to E winds into the weekend. Potential Tropical Cyclone Nine, currently in the southeastern Bahamas, will move NE toward Florida, through the end of the week. The gradient, between the cyclone and the high pressure, will allow for east winds to increase in the far NE Gulf of Mexico from Friday night into Saturday, along with building seas. Scattered rainshowers and thunderstorms may spread westward from Florida into the eastern Gulf of Mexico, from Friday through Sunday. CARIBBEAN SEA... Isolated moderate rainshowers are in the area that is to the NW and W of the line that runs from 80W in Cuba to eastern Honduras. Part of the precipitation that is in the NW corner is related to the east central Gulf of Mexico upper level cyclonic circulation center. Another part of the precipitation is related to the cyclonic wind flow that is moving around Potential Tropical Cyclone Nine. The monsoon trough is along 10N75W in northern Colombia, southwestward, beyond southern Costa Rica, into the eastern Pacific Ocean. Widely scattered moderate to isolated strong rainshowers are from 11N southward from 75W westward. High pressure north of the area will maintain moderate trade winds, that at times will pulse to fresh to strong in the south central Caribbean Sea. A tropical wave will cross from the central sections into the western sections on Friday morning, and then exit into Central America on Sunday. A second tropical wave will enter the tropical N Atlantic Ocean and the eastern Caribbean Sea on Friday night. A third and stronger tropical wave will approach the tropical N Atlantic Ocean and the eastern Caribbean Sea during the weekend into early next week. This wave is expected to bring widespread rainshowers and thunderstorms, gusty winds and building seas. ATLANTIC OCEAN... A surface trough is along 32N50W 26N52W. Widely scattered moderate to isolated strong rainshowers are from 25N northward between 46W and 54W. Potential Tropical Cyclone Nine near 23.9N 74.7W 1009 mb at 11 PM EDT is moving NW 7 knots. The maximum sustained wind speeds are 25 knots with gusts to 35 knots. Potential Tropical Cyclone Nine will move to near 24.6N 75.6W Fri morning with maximum sustained winds 30 kt gusts to 40 kt, to near 25.5N 77.2W Fri evening. then intensify to a tropical cyclone near 26.5N 78.8W early Sat with maximum sustained winds 40 kt gusts to 50 kt. Potential Tropical Cyclone Nine is forecast to intensify slightly as it reaches to near 27.5N 80.2W Sat evening and move to just near 28.8N 81.2W by early Sun, reach to near 29.8N 81.8W Sun evening while weakening. The cyclone is forecast to move northeastward early next week, entering the waters again, just northwest of the area. A strong tropical wave may approach the waters S of 22N early next week. $$ MT