000 AXNT20 KNHC 140004 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 704 PM EST Fri Dec 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 1800 UTC surface analysis and satellite imagery through 2350 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal border area of Sierra Leone and Liberia to 06N16W. The ITCZ continues from 06N16W to 04N25W, 04N32W, and 04N39W. Precipitation: Isolated moderate to locally strong are from 08N southward from 50W eastward. GULF OF MEXICO... A stationary front passes through 32N79W in the Atlantic Ocean, to the NE Florida east coast near 30N81.5W, to the Florida west coast near 29.5N83W, to a Gulf of Mexico 1011 mb low pressure center that is near 29.5N87.5W, to 26N91W. A surface trough extends from east Texas into the Gulf of Mexico near 26.5N92.5W. Precipitation: isolated to widely scattered moderate and locally strong from 22N northward from 86W eastward, including across Florida. Upper level cyclonic wind flow covers the Gulf of Mexico from 23N northward. The upper level cyclonic wind flow is associated with the trough that has been moving the central U.S.A. during the day on Friday. The current stationary front, that is in the NE corner of the Gulf of Mexico, will transition into a cold front, as it passes across the eastern Gulf of Mexico through Saturday. The low pressure center will move NE tonight. High pressure will shift eastward across northern Florida on Sunday. The return wind flow will strengthen in the western Gulf of Mexico, in advance of an approaching cold front. This front will move off the Texas coast on Monday, and extend from the Florida Panhandle to the SW Gulf of Mexico on Tuesday. It is possible that gale-force northerly winds may be to the west of the front, near the coast of Mexico, from late Tuesday through Wednesday, as the front continues SE across the Gulf of Mexico. CARIBBEAN SEA... Broad upper level cyclonic wind flow covers the Caribbean Sea from 10N to 20N from 70W eastward. A surface trough is along 67W/68W from 17N southward. Comparatively drier air in subsidence covers the Caribbean Sea from 20N southward from 84W eastward. Precipitation: Isolated moderate from 10N to 14N between 50W and 60W, just to the east of the Caribbean Sea, in an area of an upper level trough/cyclonic wind flow. Isolated moderate in the Caribbean Sea, from 18N southward between 60W and 70W, and from 13N to 19N between 70W and 80W. Broad surface low pressure covers the SW corner of the Caribbean Sea. The monsoon trough passes through Costa Rica and northern Panama, into northern Colombia along 10N. Satellite data and the GFS forecast for 250 mb show upper level anticyclonic wind flow in the SW corner of the Caribbean Sea. The GFS model forecasts for 500 mb and for 700 mb show cyclonic wind flow in the same area. Precipitation: isolated moderate from 10N southward from 80W westward. Rainshowers are possible elsewhere from 16N southward from 78W westward, in broken to overcast low level and middle level clouds, in trade wind flow. The wind speeds and the sea heights will diminish across the region tonight, gradually, as high pressure in the Atlantic Ocean shifts eastward. The trade winds in the central and eastern Caribbean Sea will increase early next week. Fresh trade winds and moderate NE swell are expected in the Tropical N Atlantic Ocean during the weekend. ATLANTIC OCEAN... A stationary front passes through 32N79W in the Atlantic Ocean, to the NE Florida east coast near 30N81.5W, to the Florida west coast near 29.5N83W, and into the N central Gulf of Mexico. A second stationary front passes through 32N62W to 31N70W, and to 28N78W. Precipitation: widely scattered moderate to isolated strong from 25N northward from 70W westward. An upper level trough extends from a 31N38W cyclonic circulation center, to 23N53W. One part of a trough continues from 23N53W to 12N55W. Another part of a trough extends from 23N53W into the SE corner of the Caribbean Sea. A surface trough is along 31N49W 25N51W 18N53W. Precipitation: broken to overcast multilayered clouds, and isolated to widely scattered moderate and locally strong from 12N northward between 20W and 56W. The current stationary front will dissipate tonight. Southerly winds will increase tonight and on Saturday, in advance of a weak cold front that is expected to move E across the northern waters during the weekend. A stronger cold front will move off the southeast U.S.A. coast, from Tuesday night through Wednesday night, resulting in strong northerly winds and building seas. $$ MT