000 AXNT20 KNHC 201003 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Dec 20 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... NE Gulf of Mexico Gale Warning: A 1014 mb low pressure is in the NW Gulf offshore SW Louisiana near 28N93W. A cold front extends from the low to the western Bay of Campeche near 20N96.5W. A warm front extends from the low center to south of Pensacola, Florida near 29N87W. Numerous showers and scattered thunderstorms are affecting the waters N of 23N and between 84W and 94W. Fresh to strong cyclonic winds are observed N of 28N and W of 87W. Frequent gusts to gale force are occurring in the coastal waters between 88W and 91.5W. Seas in these waters are 5-8 ft. The gradient between the low and strong high pressure over the SE United States will cause winds to gale force over the NE Gulf of Mexico this afternoon. Seas will build to near 10 ft in the northern Gulf. Gale force winds are also now forecast offshore Veracruz, Mexico behind the front this afternoon and evening with seas of 8-10 ft. The low will shift toward South Florida by late tonight while the cold front slowly moves eastward, stalling and weakening by mid- week. Fresh to strong N winds are expected elsewhere behind the front through this evening. Scattered showers and thunderstorms are expected with the low and front. Winds and seas will diminish in the NE Gulf and SW Gulf late Wed into Thu. SW N Atlantic Gale Warning: A cold front from 30N55W to 26N63W continues as a shearline to across the Central Bahamas and the Straits of Florida. A few showers are noted near the frontal boundary, but no deep convection is evident. Moderate to fresh N-NW winds are present behind the frontal boundary and north of the shearline, with the strongest winds occurring near 27N70W. Seas behind the cold front are 6-10 ft, with the highest seas occurring N of 28N and E of 70W. The cold front will extend from 31N49W to 23N67W this evening. A low pres over the Gulf of Mexico will cross South Florida tonight and move ENE near the NW Bahamas Wed morning. The low pres is expected to develop gale force winds on Wed as it continues east along 26/27N to the east of the Bahamas, while seas build to 8-10 ft. These gales should diminish by early Thu as the low nears 26N65W while becoming elongated. At the same time, a second area of gales is expected to form Wed morning to the east of N Florida, associated with a sharp surface trough. Seas will build to 8-12 ft there. Winds will diminish to strong by Wed evening off N Florida. Please read the latest High Seas Forecast issued by the National Hurricane Center at http://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on both Gale Warnings. ...MONSOON TROUGH/ITCZ... The monsoon trough reaches the Atlantic through 1008 mb low pressure at the coast of Guinea near 11N14W to 05N18W. The ITCZ continues from 05N18W to 10N35W to the coast of Brazil near 02N50W. Widely scattered moderate convection is noted from the Equator to 07N between 10W and 48W. GULF OF MEXICO... Please read the Special Features section above for information on the developing gales in association with the low pressure system over the NW Gulf of Mexico, as well as offshore Veracruz, Mexico. Outside of the impacts of the low pressure mentioned above in the Special Features section, high pressure over the eastern United States dominates the rest of the Gulf of Mexico. Moderate to locally fresh easterly winds are present E of 90W. Seas in these waters are 3-6 ft, with the highest seas occurring in the Straits of Florida. Moderate or weaker winds and seas of 3-6 ft are found S of 25N and W of 90W ahead of the cold front. For the forecast, looking ahead, a stronger cold front is expected to move off the Texas coast Thu evening followed by near- gale to gale force winds and rough to very rough seas across the basin through Fri night, with strong gales possible off Veracruz. CARIBBEAN SEA... A strong ridge over the eastern United States extends southward into the Caribbean Sea, maintaining fairly tranquil weather conditions. The exception are isolated pockets of shallow moisture traversing the basin in the trade flow. The pressure gradient between the strong high pressure and lower pressure in northern South America result in fresh to strong easterly trade breezes in the central Caribbean, with the strongest winds occurring offshore Colombia. Seas in these waters are 6-9 ft. Moderate to locally fresh easterly winds were evident in earlier satellite derived wind data in the eastern Caribbean. Seas in the area described are 3-6 ft. Moderate or weaker winds and slight to moderate seas are observed elsewhere. For the forecast, surface ridging north of the region will maintain fresh to strong NE to E tradewinds across the central and SW Caribbean Sea through Sat night. Moderate to locally fresh winds will prevail in the E Caribbean with gentle to moderate winds in the W Caribbean. Moderate long-period N to NE swell will continue to move into the tropical Atlantic waters for the next several days. A cold front will move into the Yucatan Channel by late Fri and reach from central Cuba to Belize by Sat night. Fresh to locally strong winds and rough seas will follow the front. ATLANTIC OCEAN... Please read the Special Features section for details on SW N Atlantic Gale Warnings. Moderate to fresh SW winds are found ahead of the aforementioned front, mainly N of 28N and between 43W and 56W. The remainder of the tropical Atlantic waters are dominated by a 1023 mb high pressure system positioned near 27N38W. The pressure gradient between this ridge and lower pressures in the deep tropics result in moderate to fresh easterly trade winds S of 20N and between Africa and the Lesser Antilles. Seas in these waters are 6-9 ft with the highest seas occurring just WSW of the Cabo Verde Islands. Moderate or weaker winds and moderate seas prevail elsewhere in the basin, along with seas of 6-11 ft in northerly swell. For the forecast west of 55W, looking ahead, winds will become more southerly Thu ahead of a stronger cold front expected to move off the northeast Florida coast Fri, accompanied by strong to near-gale force winds and rough seas. Gales are possible to the east of northern Florida with this next front. $$ Lewitsky