000 AXNT20 KNHC 252345 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Oct 26 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 1800 UTC surface analysis and satellite imagery through 2330 UTC. ...SPECIAL FEATURES... Gulf of Mexico Gale Warning: Fresh to strong northerly winds behind a cold front that extends from southeastern Louisiana to Tampico, Mexico have recently increased to gale force in the far southwestern Gulf, over the waters of the western Bay of Campeche. Wave heights with these winds are expected to peak to 9 ft this evening and early tonight. As the gradient behind the front slackens some later tonight, this will allow for these winds to diminish to strong speeds. Please read the High Sea Forecast issued by NHC at: www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more information. Eastern Caribbean Sea Heavy Rainfall: A deep-layer trough currently northeast of eastern Cuba and extending south-southwestward to near northwest Colombia is advecting moisture across Hispaniola. It will drift eastward to north of Puerto Rico and spread moisture over the island through Wed. Meanwhile, a tropical wave just east of the Lesser Antilles will move across the eastern Caribbean Sea tonight through early Thu. These ingredients will combine this week leading to numerous showers and thunderstorms over the eastern Caribbean Seas, including Puerto Rico, the Virgin Islands and the Dominican Republic. Excessive heavy rainfall could result in localized flooding across portions of Puerto Rico, the Virgin Islands, and eastern Hispaniola through Thu. Residents in these locations should monitor this developing situation closely and stay informed with their local weather offices and authorities. ...TROPICAL WAVES... An central Atlantic tropical wave has its axis along 40W/41W from from 03N to 15N. It is moving westward around 15 kt. Scattered to numerous moderate convection is occurring within 180 nm either side of the wave from 06N to 10N. Latest ASCAT data shows moderate to fresh northeast to east winds from 06N to 11N between 35W-38W. Wave heights with these winds are in the 7-9 ft range due to a combination of wind generated waves and a long- period northeast swell. A western Atlantic tropical wave is just east of the Lesser Antilles with its axis along 60W/61W from 06N to 19N. It is moving westward at about 15 kt. Scattered moderate convection is seen within 180 nm east of the wave from 13N to 15N and within 120 nm west of the wave from 13N to 16N. Latest ASCAT satellite scatterometer data show fresh easterly winds with 7 to 9 ft seas near and east of the wave from 11N to 17N between 55W-59W. The previous central Caribbean Sea tropical wave that was along 77W is analyzed as a trough at 18Z. See Caribbean Sea section for information on this feature. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic along the African coast near Bissau to 11N20W, where latest scatterometer data indicates that it transitions to the ITCZ to east of a tropical wave near 08N39W. It resumes at 07N42W northwest to 09N52W and to just east of a tropical wave near 13N59W. Scattered moderate convection is within 180 nm north of the ITCZ between 43W-55W, within 120 nm south of the ITCZ between 35W-37W and from 08N to 13N between 30W-35W. The eastern segment of the eastern Pacific monsoon trough protruded into the southwestern Caribbean Sea roughly along 10N/11N and to near northwest Colombia. Isolated showers and thunderstorms are near the trough, and over the interior sections of Costa Rica and Panama. ...GULF OF MEXICO... Refer to the Special Features section gale force winds west of a cold front over the western Bay of Campeche. A cold front is analyzed from southeastern Louisiana to inland Tampico, Mexico. Scattered showers and isolated thunderstorms are ahead of the front to near 87W and from 25N to 29N. Convergent southerly winds farther southeast is creating similar conditions at the central Gulf. Fresh to strong northerly winds and wave heights of 6-8 ft are behind the front over the northwestern Gulf. Fresh northerly winds with wave heights of 5-7 ft are near the front over the north-central Gulf. A surface ridge extends from a 1015 mb high over central Florida to the Yucatan Peninsula. Its associated gradient is supporting gentle to moderate southerly winds along with wave heights of 2-4 ft for the rest of the Gulf. For the forecast, aside from the gale force winds that are over the western Bay of Campeche behind the aforementioned cold front, fresh to strong northwest to north winds are elsewhere behind the front. Moderate southerly winds are east of the front and north of 26N. Occasional and local gusts to gale force just behind the front are possible this evening, while sustained gales off Veracruz, Mexico in the western Bay of Campeche will occur this evening. This front will reach from Mobile Bay, Alabama to the western Bay of Campeche by late this evening, then will slow down and weaken, gradually dissipating Wed night into Thu. Moderate to fresh return flow will develop across NW portions Thu night through Fri, ahead of the next approaching cold front, which should move off the Texas coast Fri afternoon. This next front may stall and weaken in the central Gulf this weekend. ...CARIBBEAN SEA... Please read the Special Features section for potential heavy rain across the eastern Caribbean Sea this week. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for convection in the Caribbean Basin. What was previously a tropical wave along 77W is now analyzed as a surface trough from 18N71W to 15N73W and to 12N74W. Enhanced by the deep-layer trough and associated moisture mentioned in the Special Features section, numerous heavy showers and scattered thunderstorms continue to flaring up over the central Caribbean Sea, including southern Hispaniola. Moderate to locally fresh easterly winds with wave heights of 3-5 ft seas are over the central part of the seas and Gulf of Honduras. Mainly gentle easterly trades and wave heights of 2-4 ft are over the rest of basin. For the forecast, a weak pressure gradient across the regional Atlantic and Caribbean will maintain gentle to moderate trade winds and light to moderate seas through early Wed. A deep layered trough is expected to develop across the central Caribbean today through Wed and lift northward Thu and Fri. A tropical wave along 59W will move westward and become absorbed within the trough along 67W Wed night through Thu. These features will induce numerous thunderstorms across the eastern half of the basin later today through Thu. Fresh to locally strong trade winds and increasing east swell are moving into Tropical Atlantic waters, behind the tropical wave, and will gradually shift into the far eastern Caribbean tonight through Wed. An area of low pressure could form over the eastern Caribbean Sea by early this weekend. ...ATLANTIC OCEAN... A sharp deep-layer trough stretches from near 31N77W to an elongated upper-level low near 27N73W and continues to eastern Cuba and to the Caribbean Sea to near northwest Colombia. This extensive feature is causing scattered showers and isolated thunderstorms from the central and southeast Bahamas northward between 67W-76W. An upper-level low near 29N56W is producing scattered moderate convection north of 25N between 47W-57W. A modest cold front extends from a 1010 mb low that is north of the area near 35N21W, southwestward to 29N30W, westward to 29N40W and northwestward to 31N46W. Isolated showers are possible along and near the front. A surface trough is along 31W from 20N to 25N, and another one is along 41W from 20N to 25N. No convection is occurring with these features. Only isolated showers are possible near the second trough. A weak Atlantic ridge is sustaining light to gentle winds and wave heights of 3-5 ft north of 22N between the northwest African coast and 65W. To the west, gentle to moderate northeast to east winds along with wave heights of 4-6 ft are north of 20N between 65W and the Georgia-Florida coast. Further south outside the influence of the tropical waves, gentle to moderate northeast to east winds and wave heights of 6-9 ft are north of 08N between the central African coast and Lesser Antilles. Gentle to moderate southerly winds and wave heights of 5-7 ft due to southerly swell remain over the rest of the basin. For the forecast west of 55W, scattered to numerous showers and thunderstorms continue across the Atlantic waters between 65W and 75W, associated with a deep layer upper-level trough. The trough will drift slowly eastward through Thu and produce very active weather. Low pressure is expected to develop near 28N67W by Thu night and move to near 31N68W Fri night where it will become stationary through the upcoming weekend. $$ Aguirre