000 AXNT20 KNHC 140557 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1257 AM EST Fri Dec 14 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 0000 UTC surface analysis and satellite imagery through 0530 UTC. ...SPECIAL FEATURES... ...Gulf of Mexico Gale Warning... As of 0300 UTC, a cold front extends over the western Gulf of Mexico from near Lake Charles Louisiana to 27N94W to the coast of Mexico near 24N98W and inland into Mexico. A recent ASCAT pass from around 0300 UTC shows gale force winds behind the front from 24N-29N, W of 94.5W. The front will reach from the Florida Big Bend to the Yucatan Channel by late today, then move through the Bahama Channel on Sat. The gale force winds will continue this morning west of the cold front, spreading southward through the west-central Gulf. Winds are forecast to be below gale force by late this afternoon. Seas of 13 to 17 ft are expected to affect waters today from 22N-28N between 90W-97W. Please read the latest High Seas Forecast under AWIPS/WMO headers HSFAT2/FZNT02 KNHC for more details. ...Possible Gale off the coast of Morocco... Widespread strong to near gales with localized winds to gale force are expected later today within 120 nm of the coast of Morocco between 30N-32N in Agadir, according to the latest forecast from Meteo France. These winds are being caused by a strong pressure gradient between a strong low over the western Mediterranean Sea and a high pressure to the west over the Atlantic near 32N18W. Winds will diminish by early Sat. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Sierra Leone near 09N13W to 08N15W. The ITCZ continues from that point to 04N20W to 00N32W to 01S44W. Scattered moderate convection is seen from 04N-08N between the W coast of Africa and 21W. Isolated to scattered showers are seen from 07N southward between 34W and the coast of South America. GULF OF MEXICO... A cold front and associated gale force winds in the western Gulf are described above in the Special Features section. A strong, deep-layered low pressure system is located over east-central Texas. CIRA Layered Precipitable Water imagery indicates that southerly flow east of the low is drawing a large amount of moist air northward from the western Caribbean into the NE and north- central Gulf of Mexico. Well ahead of the cold front, over the eastern Gulf of Mexico, numerous moderate and scattered strong convection is noted from 24N-29N between 83W-88W. Elsewhere N of 24N and E of 89W, scattered moderate convection is seen. In addition, a line of showers and thunderstorms is occurring along with, or just ahead of the cold front over Louisiana. This line extends southward into the northern Gulf off the coast of south- central Louisiana, moving eastward. Fresh to strong southerly flow will continue today east of the cold front that is currently over the western Gulf of Mexico. The strong thunderstorms currently over the NE Gulf will continue through this morning. Strong wind gusts and locally enhanced seas are expected with the stronger thunderstorms. The pressure gradient will relax tonight and Sat, with moderate west flow expected on Sat evening as the seas subside to less than 8 ft. The gradient will continue to relax with light northerly winds on Mon. CARIBBEAN SEA... There are no significant features or convection over the Caribbean at this time. Water vapor imagery shows relatively dry air over the eastern and central Caribbean. Other than some light trade wind showers in the vicinity of Puerto Rico and Trinidad, the basin is quiet. Fresh to strong trade winds will prevail across the south-central Caribbean through the upcoming weekend, with nocturnal pulses to near gale-force off the northwest coast of Colombia. These winds will expand north across the central Caribbean today. A cold front will enter the Yucatan Channel late this afternoon, then stall and gradually dissipate over the NW Caribbean into early next week. Strong north winds are forecast west of the front across the Gulf of Honduras late tonight and Sat. Large north swell will reach the Leewards on Sat, and spread south through the northeast Caribbean passages during the weekend. ATLANTIC OCEAN... Scattered showers and isolated thunderstorms originating from the activity occurring over the NE Gulf of Mexico are now starting to spread into the Atlantic waters east of Georgia and northern Florida west of 78W and north of 28N. Expect strong thunderstorms to become widespread in this area later today. A cold front passes through 32N42W to 27N50W to 24N61W then transitions to a warm front at that point, extending to 23N67W to the central Bahamas. Scattered showers are within 60 nm of the front north of 31N. Elsewhere along and north of the front, isolated showers are noted. Farther to the southeast, a surface trough is analyzed from 28N42W to 17N45W. Broken clouds and isolated showers accompany the trough. The frontal boundary that extends eastward from the central Bahamas will continue to drift northward today, then gradually wash out as it continues north across the northeast portion on Sat. Strong to near-gale southerly return flow will develop north of the Bahamas today ahead of another cold front that will sweep east across the northern waters during the upcoming weekend, extending from Bermuda to northwest Cuba on Sun night and from 31N71W to central Cuba on Mon. The front will stall as it passes across the waters north of the Antilles early next week. For additional information please visit http://www.hurricanes.gov/marine $$ Hagen