505 AXNT20 KNHC 041905 AAA TWDAT Tropical Weather Discussion...UPDATE NWS National Hurricane Center Miami FL 142 PM EDT Tue Sep 4 2018 UPDATED FOR T.S. GORDON POSITION AND INFORMATION 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 1200 UTC surface analysis and satellite imagery through 1845 UTC. ...SPECIAL FEATURES... The center of Tropical Storm GORDON at 04/1800 UTC is near 28.9N 87.3W, or about 110 nm/205 km to the SSE of Mobile in Alabama, or about 125 nm/235 km to the SE of Biloxi in Mississippi. GORDON is moving NW, or 305 degrees, 13 knots. The estimated minimum central pressure is 1001 mb. The maximum sustained wind speeds are 55 knots with gusts to 65 knots. Scattered to numerous strong rainshowers are within 165 nm of the center in the NE quadrant, and within 100 nm of the center in the NW quadrant Scattered moderate to isolated strong rainshowers are within 240 nm of the center in the SE quadrant. Widely scattered moderate to isolated strong rainshowers are elsewhere from 24N to 32N between 82W and 90W, including inland in Florida to the east of GORDON, and inland in the Florida Big Bend and in the Florida Panhandle. The PUBLIC ADVISORIES about Tropical Storm GORDON are issued under the WMO header WTNT32 KNHC and under the AWIPS header MIATCPAT2. The FORECAST/ADVISORIES about Tropical Storm GORDON are issued under the WMO header WTNT22 KNHC, and under the AWIPS header MIATCMAT2. The center of Hurricane FLORENCE at 04/1500 UTC is near 19.7N 42.5W. FLORENCE is moving WNW, or 295 degrees, 10 knots. The estimated minimum central pressure is 990 mb. The maximum sustained wind speeds are 65 knots with gusts to 80 knots. Scattered to numerous strong rainshowers are within a 90 nm radius of the center in the N semicircle, and within 60 nm of the center in the SW quadrant. Scattered moderate to isolated strong rainshowers are elsewhere within 120 nm of the center in the N semicircle and in the SE quadrant. Isolated moderate to locally strong rainshowers are in the remainder of the area from 17N to 26N between 37W and 44W. The PUBLIC ADVISORIES about Tropical Storm FLORENCE are issued under the WMO header WTNT31 KNHC and under the AWIPS header MIATCPAT1. The FORECAST/ADVISORIES about Tropical Storm FLORENCE are issued under the WMO header WTNT21 KNHC, and under the AWIPS header MIATCMAT1. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 22W/23W from 21N southward. A 1007 mb low pressure is along the tropical wave near 10N. Widely scattered moderate to isolated strong rainshowers are from 12N to 16N between 21W and 25W, and from 07N to 10N between 25W and 30W. Isolated moderate rainshowers are elsewhere from 02N to 17N between Africa and 30W. A Caribbean Sea tropical wave is along 74W/76W, from 21N in SE Cuba, to northern Colombia. The wave is moving through an area of upper level cyclonic wind flow, with an elongated NE-to-SW oriented trough. Isolated moderate to locally strong rainshowers are within 60 nm on either side of the line from 15N80W, through the Jamaica Channel, through the Windward Channel, to the SE Bahamas. A tropical wave is moving through the SW corner of the Gulf of Mexico, along 94W/95W from 21N southward, across the Isthmus of Tehuantepec of southern Mexico. Rainshowers are possible within 150 nm on either side of the tropical wave. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal near 15N17W, to a 1007 mb low pressure center, that is along the 22W/23W tropical wave, near 10N. The monsoon trough continues to 09N26W and 11N32W. The ITCZ is along 10N45W, to 06N59W in Guyana. Widely scattered moderate to isolated strong rainshowers are along the coast from 05N to 10N between land and 17W. Isolated moderate to locally strong rainshowers are from 03N to 10N between 40W and 60W. Isolated moderate rainshowers are from 03N south between 33W and 40W. ...DISCUSSION... GULF OF MEXICO... Please read the SPECIAL FEATURES section for details about Tropical Storm Gordon. An upper level trough is to the west of Gordon, from SE Louisiana to the Yucatan Peninsula of Mexico. Upper level cyclonic wind flow is inland in Mexico, from 25N southward between 96W and 106W. Widely scattered moderate to isolated strong rainshowers are in the Gulf of Mexico from 20N northward between 90W and 96W. Scattered moderate to isolated strong rainshowers are in the Yucatan Peninsula of Mexico. Gordon is forecast to move NW during the next 24 hours. It is forecast to strengthen into a hurricane tonight, and then make landfall later tonight. The wind speeds and the sea heights will diminish across the eastern and north central Gulf of Mexico in the wake of Gordon. CARIBBEAN SEA... An upper level trough passes through the Atlantic Ocean, just to the north of Hispaniola, along a NE-to-SW line, toward Jamaica and eastern Honduras/NE Nicaragua. Isolated moderate rainshowers cover the Caribbean Sea from 13N northward from 70W westward. The easternmost part of the monsoon trough is along 08N/10N from 74W in Colombia beyond western Panama and southern Costa Rica. Widely scattered moderate to isolated strong rainshowers are from 11N southward from 75W westward. The current 74W/76W tropical wave, that extends from western Cuba to Colombia, will pass through the western Caribbean Sea by late Wednesday. A relatively weak surface ridge, that is to the north of the region, will maintain moderate to fresh trade winds mostly everywhere, through Saturday. ATLANTIC OCEAN... Please read the SPECIAL FEATURES section for details about Hurricane Florence. Upper level cyclonic wind flow covers the Atlantic Ocean from 20N northward from 46W westward. Widely scattered moderate to isolated strong rainshowers are from 30N northward between 55W and 61W. Isolated moderate rainshowers are elsewhere in the area of upper level cyclonic wind flow. A weak pressure pattern will maintain gentle to moderate easterly winds across the area through Saturday. Easterly swell from Hurricane Florence will move into the open waters east of the Bahamas starting late Wednesday. For additional information please visit http://www.hurricanes.gov/marine $$ MT