000 AXNT20 KNHC 131803 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 103 PM EST Thu Dec 13 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 1200 UTC surface analysis and satellite imagery through 1745 UTC. ...SPECIAL FEATURES... ...Gulf of Mexico Gale Warning... A cold front is forecast to enter the northwest Gulf of Mexico this afternoon. The forecast, from 13/1200 UTC, is for the cold front to be along 30N93W 26N93W 21N97W. Expect W-to-NW GALE- FORCE winds, and sea heights to 10 feet, N of 26N W of the cold front. Please read the latest High Seas Forecast under AWIPS/WMO headers HSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough remains inland in Africa. The ITCZ passes through the coastal sections of Guinea near 10N13W, to 09N15W 05N20W 02N27W and 01N35W. Widely scattered moderate to isolated strong rainshowers are from 05N southward between 36W and 52W, including in coastal sections of Brazil. Isolated moderate to locally strong rainshowers are from 08N southward from 22W eastward. Rainshowers are possible elsewhere from 10N southward from 60W eastward. GULF OF MEXICO... An upper level trough is digging through Texas. The trough is supporting a cold front that is moving southeastward, across and through Texas, toward the NW corner of the Gulf of Mexico. Broken to overcast multilayered clouds and isolated moderate to locally strong rainshowers are to the west and northwest of the line that runs from north Florida near 30N82W, to the central Gulf of Mexico near 24N90W, to the coast of Mexico near 20N96W. Fresh to strong southerly wind flow will continue to the east of a cold front that is moving off the Texas coast. The front will reach from the Mississippi Delta to the Bay of Campeche tonight, from the Florida Big Bend to the Yucatan Channel late on Friday, and move through the Bahama Channel on Saturday. Strong to near gale force northwesterly wind flow to the west of the front will increase to gale force this evening in the northwest Gulf of Mexico waters, with 30 to 40 knot wind conditions spreading south across the west central Gulf late tonight into Friday. The pressure gradient will relax on Friday night and Saturday, with moderate west flow expected on Saturday evening as the sea heights subside to less than 8 feet. The pressure gradient will continue to relax, with light northerly winds on Monday. CARIBBEAN SEA... A surface trough is in the NW Caribbean Sea, along 20N83W 18N85W, to 15N85W in eastern Honduras. Rainshowers are possible from 15N northward from 80W westward. Isolated moderate rainshowers are from 17N southward between 66W and 75W, and to the east of the line that runs from Puerto Rico to the SE corner of the Caribbean Sea, and around Jamaica. 24-hour rainfall totals that are listed for the period that ended at 13/120000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES... MIATPTPAN/SXCA01 KNHC...are 0.28 in Montego Bay in Jamaica, 0.04 in Guadeloupe, 0.03 in San Juan in Puerto Rico. The monsoon trough is along 07N/08N from 73W in Colombia beyond 84W in the eastern Pacific Ocean. Isolated moderate rainshowers are from 12N southward from 75W westward. A middle level trough also is in the SW corner of the Caribbean Sea. Fresh to strong trade winds will prevail across the south central Caribbean Sea through the upcoming weekend, with nocturnal pulses to near gale force off the northwest coast of Colombia. These strong trade winds will expand northward across the entire central Caribbean Sea on Friday and Friday night. The remnants of a frontal trough will dissipate gradually in the northwest Caribbean Sea through Friday. A cold front will enter the Yucatan Channel on Friday afternoon, stall and then gradually dissipate in the NW Caribbean Sea into early next week. Strong north winds are forecast to the west of the front across the Gulf of Honduras late Friday night and Saturday. Large north swell will reach the Leeward Islands on Saturday, and spread southward through the northeast Atlantic Ocean passages during the upcoming weekend. ATLANTIC OCEAN... A cold front passes through 32N48W to 27N56W to 24N64W. The front continues as stationary from 24N64W to 22N70W to SE Cuba. Broken multilayered clouds and isolated moderate rainshowers are to the west and NW of the line that runs through 32N44W to 23N60W to SE Cuba. One surface trough is along 42W from 17N to 25N. Scattered to broken to low level clouds are on the western side of the trough. Rainshowers are possible from 10N to 20N between 38W and 44W. A second surface trough is along 56W/57W from 15N to 22N. Rainshowers are possible from 08N to 22N between 54W and 62W. The current frontal boundary will drift northward, and extend east to west along 25N on Friday. The frontal boundary will wash out, gradually, as it continues northward across the northeast part of the area on Saturday. Strong to near gale southerly return wind flow will develop north of the Bahamas tonight and on Friday. Those will be the wind conditions ahead of another cold front that will sweep east across the northern waters during the upcoming weekend. The second cold front will reach a position from Bermuda to northwest Cuba on Sunday night, and from 31N71W to central Cuba on Monday. The front will stall as it passes across the waters north of the Antilles on Tuesday. For additional information please visit http://www.hurricanes.gov/marine $$ MT