000 AXNT20 KNHC 160842 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Fri Dec 16 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 0800 UTC. ...SPECIAL FEATURES... Central Atlantic Gale Warning: A large and powerful 982 mb low pressure system north of the area near 38N48W is supporting strong to gale force winds and very large seas north of 30N between 43W and 55W, with storm force winds north of 31N. Recent altimeter passes showed seas in this area of 20 to 23 ft along 31N. Winds will diminish below gale force later this morning as the low north of the area tracks northeast, thus reducing the pressure gradient over the north-central subtropical Atlantic waters. 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. East Atlantic Gale Warning: A 998 mb low north of the area near the coast of Portugal near 40N09W is producing gale force winds over the adjacent waters. A gale warning is in effect for Meteo- France High Seas Zone Irving and for additional zones north of there. Please read the latest High Seas Forecast issued by Meteo- France at website gmdss.org/II.html for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic tropical waters through the coast of Sierra Leone near 08.5N13W to 06N17W. The ITCZ continues from 06N17W to 04N35W to near the coast of Suriname at 06N56W. Scattered moderate isolated strong convection is present from the Equator to 07N between 21W and 45W. Scattered moderate convection is present from 05N to 08N between 45W and 53W. GULF OF MEXICO... A cold front extends from near Fort Myers, Florida southwest where it stalls just north of the Yucatan Peninsula. An earlier squall line ahead of the front is now a remnant trough stretching from near Naples, Florida to the north-central Yucatan Peninsula. New scattered thunderstorms have developed along central portions from 23N to 25N between 83W and 86W. A 1019 mb high is located over SW Louisiana and supports a weak ridge in the wake of the front. This pattern is providing gentle to moderate N to NE winds north and west of the front with seas in the 3-6 ft range, except E to SE winds in the west-central and NW Gulf closer to the high. Light to gentle variable winds and seas to 3 ft are over the far SE gulf ahead of the front, except southerly moderate winds through the Yucatan Channel. For the forecast, the front will become completely stationary by this afternoon, extending from the Straits of Florida to the W central Gulf. A secondary push of cold air over the NW Gulf will reinvigorate the front and cause it to reach from the Straits of Florida to the Bay of Campeche by Sun morning. A large area of fresh to near gale N to NE winds should occur over the N, central and W Gulf this weekend. The cold front should dissipate just southeast of the basin by Mon morning. Another front may impact the Gulf Tue and Tue night. CARIBBEAN SEA... High pressure anchored by a 1019 mb high NE of the Bahamas near 28N66W extends a ridge north of the Caribbean. This high combined with lower pressure over Colombia continues to support fresh to strong trade winds in the south-central basin, including in the Gulf of Venezuela. Seas in that region are in the 8-10 ft range. Moderate to fresh trades are present in the E and SW Caribbean along with seas of 4 to 7 ft. Gentle to moderate winds dominate the waters in the NW basin with seas of 3 to 5 ft. Scattered showers and isolated thunderstorms are in the southern Nicaragua, Costa Rica and western Panama Caribbean offshore waters associated with E Pacific monsoon trough. 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 at least Tue night with moderate to locally fresh winds elsewhere. Large, long-period N to NE swell will continue to propagate across the Tropical N Atlantic and through the Mona and Anegada Passages for the next several days. A cold front will dissipate as it pushes into the NW Caribbean Sun night into Mon. ATLANTIC OCEAN... See the Special Features section above for details on Gale Warnings in the central Atlantic and east Atlantic. A cold front is offshore the Carolinas to near Fort Piece, Florida. Fresh to strong SW winds are ahead of the front north of 29N between 71W and 79W, along with seas of 7-10 ft. Scattered showers and isolated thunderstorms are within 150 nm southeast of the front mainly north of 28N. High pressure anchored by a 1019 mb high NE of the Bahamas near 28N66W extends a ridge across the SW N Atlantic waters ahead of the front, supporting light to gentle variable winds near the high, with gentle to moderate winds elsewhere west of 60W. East of the high, a cold front associated with the large and powerful low pressure system described in the Special Features section extends through 31N48W extending to 27N56W, then as a dissipating stationary front to 26N65W. Otherwise, the remainder basin is dominated by a broad subtropical ridge with moderate to fresh trades south of 20N, and gentle to moderate trades north of 20N away from the Special Feature surrounding area. Seas are 7 to 10 ft in N to NE swell across these waters, except 4 to 6 ft southeast of the Cabo Verde Islands. For the forecast west of 55W, a powerful low pressure system northeast of the area will move away with fresh to strong winds north of 28N and east of 58W diminishing this morning. A cold front from 31N77W to near Fort Pierce, Florida will reach from near 31N64W to the Florida Keys by Sat morning, and dissipate on Sun. A second cold front will move off the the SE United States coast Sat night, extend from 31N58W to the SE Bahamas Mon morning, before weakening and becoming stationary from 28N55W to the SE Bahamas Tue morning. Large, long-period N to NE swell will continue to affect much of the area for the next several days. $$ Lewitsky