000 AXNT20 KNHC 141737 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Dec 14 2022 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... Central Atlantic Gale Warning: A large and powerful low pressure system centered north of the area near will bring strong to near gale force W winds tonight through Thu night to the waters east of 65W and north of 27N. Very large seas can be expected in this area. By Thu night, the forecast calls for W to NW winds of 30-35 kt N of 30N between 47W and 54W with seas of 17-23 ft in NW swell. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coast of Sierra Leone near 08N13W to 07N17W. The ITCZ continues from 07N17W to 04N30W to 02N50W. Scattered moderate convection is noted north of the ITCZ from 03.5 to 06.5N between 24W and 45W. GULF OF MEXICO... As of 1500 UTC, a cold front has entered the NW Gulf of Mexico, and extends from SW Louisiana to NE Mexico. A band of showers and thunderstorms is associated with the front over the Gulf waters. Recent scatterometer data and buoys observations indicate fresh to strong southerly winds over the western Gulf, ahead of the front, with seas of 6-8 ft N of 22N, and 4-6 ft over the Bay of Campeche based on altimeter data. A dissipating stationary front is analyzed over the eastern Gulf, and runs from the Florida Panhandle to south Florida. Fresh to locally strong SE-S winds and seas of 4-6 ft are noted on the W side of the latter front. For the forecast, fresh to strong southerly return flow will prevail over the central and western Gulf today ahead of the cold front forecast to reach from Apalachicola, FL to the central Bay of Campeche early Thu and from Sarasota, FL to the central Bay of Campeche Thu night before slowing down and beginning to weaken. A line of strong to severe thunderstorms is expected to accompany the front today over the NW Gulf, and tonight into Thu across the north-central and NE Gulf of Mexico. Strong to locally near-gale force northerly winds are expected immediately behind the front today in the western Gulf, diminishing to moderate to fresh N winds behind the front tonight into Thu for the central and eastern Gulf. The front should become stationary Fri night from the Florida Keys to the south-central Gulf of Mexico before weakening further. The front should remain in about the same position through Sat as a surface trough forms over the SW Gulf. The gradient between this surface trough and high pressure over the southern U.S. is likely to induce a large area of fresh to strong N to NE winds over the central Gulf this weekend. CARIBBEAN SEA... Satellite derived wind data provide observations of fresh to strong trade winds over the south-central Caribbean, near the coast of Colombia. Fresh to locally strong winds are occurring just S of Haiti, and in the Gulf of Honduras with mainly fresh E winds in the Windward passage and downwind to near 77W. Moderate to locally fresh winds prevail elsewhere. Seas are 6-8 ft in the south-central Caribbean and 3-6 ft elsewhere, except up to 6-7 ft in the NE Caribbean passages due to NE swell from the Atlantic. Strong winds in the upper atmosphere support abundant cloudiness over the SE Caribbean and the Leeward Islands, particularly S of Guadeloupe. Some shower activity has been reported in the ABC Islands. Elsewhere, patches of low level moisture with embedded showers are moving across the basin in the trade wind flow. For the forecast, high pressure building east of Florida will maintain fresh to strong trade winds across the central Caribbean Sea through Fri, with moderate to fresh winds elsewhere. Large long-period N to NE swell will continue to propagate through the NE Caribbean passages and affect the Tropical N Atlantic waters for much of the week. Another large set of N swell is forecast to begin propagating through the Tropical N Atlantic waters starting late on Fri and continue through Sun night. ATLANTIC OCEAN... See the Special Features section above for details on a Gale Warning in the central Atlantic. A cold front enters the forecast area near 31N50W and continues SW to the SE Bahamas where it becomes stationary to south Florida. Scattered showers and thunderstorms are along the frontal boundary E of 57W. Fresh to locally strong SW winds are N of 29N E of the front to about 45W based on scatterometer data. Mainly gentle to moderate winds prevail elsewhere on either side of the front. Seas of 8-12 ft in N-NE swell follow the front especially E of 60W. High pressure, with a 1023 mb center located N of area near 33N34W dominates the eastern Atlantic. A dissipating frontal boundary is producing strong to near gale force SW-W winds and rough or very rough seas near the coast of Morocco. Seas of 8-12 ft in NW swell are noted between the Madeira and the Canary Islands. An area of showers and thunderstorms is observed E of a surface trough that extends from 20N56W to 12N58W. The convective activity covers the waters from 17N-22N between 50W-55W. A diffluent pattern aloft is helping to induce this convection. For the forecast west of 55W, the aforementioned cold front will weaken today as high pressure builds in east of Florida. Large long-period N to NE swell will continue to affect much of the area for the next couple of days. Farther west, fresh to strong southerly winds will develop offshore NE Florida beginning tonight as a strong cold front approaches the southeastern U.S. coast. The front is forecast to move off the coast late Thu, reach from near 31N74W to West Palm Beach, FL early Fri, and from near 31N65W to the Florida Keys early Sat. Scattered to numerous showers and thunderstorms are likely to move offshore the Florida coast on Thu. On Sun, a reinforcing cold front is expected to merge with it. The merged front is expected to reach from near 31N62W to the central Bahamas and western Cuba Sun night. The fresh to strong southerly winds will shift eastward across the northern and central waters through Sat and exit the area late Sat. Fresh northwest to north winds will follow in behind the merged front. $$ GR