000 AXNT20 KNHC 111703 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1203 PM EST Wed Dec 11 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 1200 UTC surface analysis and satellite imagery through 1650 UTC. ...SPECIAL FEATURES... GULF OF MEXICO GALE WARNING... Northerly gales continue in the southwestern Gulf of Mexico behind a cold front. The gale force winds are expected to continue south of 21N and west of 94W through this evening before diminishing. Sea heights of 12-16 ft are expected in the area. See the latest NWS High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for further details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Sierra Leone near 08N13W to 06N18W. The ITCZ continues from 06N18W to 00N43W. Isolated to scattered moderate convection is seen within 240 nm of the monsoon trough and ITCZ between the west coast of Africa and 37W. GULF OF MEXICO... A cold front extends from near Clearwater Florida to 26N90W to 24N92W to 17N94W. Gale force winds are over the southwest Gulf of Mexico behind the front. See section above for details on the Gale Warning. Elsewhere behind the front, strong to near gale force winds prevail over the northern and western Gulf of Mexico. A pre-frontal trough is over the eastern Bay of Campeche from 24N91.5W to 18N93W. Scattered moderate showers and tstorms are seen along the pre-frontal trough north of 20N. Isolated to scattered showers and tstorms are elsewhere within 30 nm behind and 120 nm ahead of the cold front, west of 86W. Scattered showers are also occurring in the NE Gulf of Mexico in between the western Florida panhandle and the Delta region of SE Louisiana. Scattered showers and isolated tstorms are also seen near the lower Florida Keys. Dry air is filtering in over the NW Gulf of Mexico behind the front. The cold front will become stationary from Tampa Bay to the Bay of Campeche tonight. The front will weaken through Thu, with frontal remnants lifting back to the north through Fri night as low pressure forms over the west-central Gulf. This low will track northeastward across the north-central waters through early Sat, with the associated cold front sweeping across the eastern Gulf through Sat night. The front will leave behind a dissipating boundary across the far SE Gulf on Sun. High pressure will build southward across the central and eastern Gulf in the wake of this front with fresh to strong southerly flow setting up over the western Gulf by late Sun. CARIBBEAN SEA... A mid to upper-level low is centered generally near 20N60W. Scattered moderate showers and tstorms are affecting portions of the Leeward and Virgin Islands north of 15.5N and east of 64.5W. Isolated showers and tstorms are elsewhere in the Caribbean east of 66.5W and north of 15N. Drier weather is over the north-central and northwestern Caribbean. Scattered showers and isolated tstorms are affecting the far SW Caribbean in association with the east Pacific monsoon trough. Additional isolated to scattered showers are seen over the remainder of the southern Caribbean south of 13.5N. The latest ASCAT pass shows strong trades over the central Caribbean from 10.5N-17N between 71W-80W. Winds and seas will gradually diminish across the region through Fri as high pressure in the central Atlantic shifts eastward. ATLANTIC OCEAN... A cold front extends from 32N76W to New Smyrna Beach Florida near 29N81W to Clearwater Florida. A pre-frontal trough is from 30N77W to 27N79W. Scattered moderate convection is near the pre-frontal trough. A surface trough is from 30N65W to 23N67W with possible isolated showers near the trough. A mid to upper-level low is centered generally near 20N60W. Scattered moderate showers and tstorms are from 17N-26N between 55W-64W. An upper-level trough extends northeastward from the upper-low to 28N50W to 31N41W. A few showers are located underneath the upper-trough axis. At the surface, ridging prevails across the most of the basin, anchored by a 1044 mb high near 39N32W. The latest ASCAT pass shows that trade winds are mostly in the 18-25 kt range across the Atlantic from 15N-32N between 20W-58W. The cold front that extends from 32N76W to New Smyrna Beach Florida will reach from near 31N73W to West Palm Beach by late tonight and from near 31N70W to 28N76W and stationary to West Palm Beach on Thu and gradually weaken through Fri. Fresh to strong northeast winds are expected north of the front tonight through late Thu night, while large seas are expected over the waters north and northeast of the Bahamas through early Fri. Fresh to strong southerly winds will develop over the far north-central waters beginning late on Fri night. These winds will expand eastward through Sat night ahead of the next cold front forecast to move off the southeastern U.S. coast on Sat. This front will quickly move across the waters north of 27N through Sun night, with the fresh to strong winds lifting NE of the area Sun night. In the far northeastern Atlantic, near gale NE winds are expected Thursday and Thursday night from the coast of Morocco through the Canary Islands. $$ Hagen