000 AXNT20 KNHC 271744 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Oct 27 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 1720 UTC. ...SPECIAL FEATURES... Caribbean Sea Heavy Rainfall: A deep layer trough, from eastern Hispaniola to the central Caribbean Sea, has become stationary. A surface trough passes through 31N70W to 26N70W, to 10N66W at the coast of Venezuela. Precipitation: widely scattered to scattered moderate and isolated strong is within 540 nm to the east of the surface trough, in the Atlantic Ocean and in the Caribbean Sea. A 69W tropical wave is moving toward the central sections of the Caribbean Sea. The deep layer trough and the tropical wave will combine in order to produce numerous strong convective precipitation in the eastern Caribbean Sea: in Puerto Rico, in the US/UK Virgin Islands, and in the Dominican Republic, through Friday. It is likely that excessive heavy rainfall will result in localized flooding in parts of these islands through at least Thursday evening. All residents in these locations should monitor closely this developing situation. Please, stay informed with bulletins and warnings from your local weather offices and authorities. The deep layer trough and the tropical wave will merge by Friday, and shift westward and weaken. An area of low pressure is expected to form in the eastern Caribbean Sea during the upcoming weekend. The environmental conditions are forecast to be conducive for gradual development. It is possible that a tropical depression may form by early next week. The feature is forecast to move generally westward or west-northwestward through the central Caribbean Sea. The Southwestern Atlantic Ocean: A trough of low pressure covers the areas that are from the eastern Caribbean Sea northward to the southwestern Atlantic. Disorganized rainshowers, some with thunder, continue to be associated with the trough. A surface low pressure center is expected to develop later today in the area of the northern part of the trough. The environmental conditions appear to be marginally conducive for additional subtropical development. It is possible that a subtropical depression may form during the next couple of days. This weather system initially will be moving northward. It is forecast to meander to the west or southwest of Bermuda. The upper level winds are forecast to be less conducive for development by this weekend. The chance of formation into a tropical cyclone during the next 48 hours is medium. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 47W/48W, from 18N southward. The wave is moving westward about 15 knots. Precipitation: scattered to numerous strong is from 13N to 17N between 41W and 45W. A Caribbean Sea tropical wave is along 69W, from the eastern parts of the Dominican Republic southward, moving westward from 5 knots to 10 knots. A surface trough passes through 31N70W to 26N70W, to 10N66W at the coast of Venezuela. Precipitation: widely scattered to scattered moderate and isolated strong is within 540 nm to the east of the surface trough, in the Atlantic Ocean and in the Caribbean Sea. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains Guinea near 12N15W to 10N17W. The ITCZ continues from 10N17W, to 06N22W 06N33W 08N44W 11N48W 10N60W. Precipitation: widely scattered moderate to isolated strong is from 15N southward between 49W and 60W, and from 10N southward from 49W eastward. ...GULF OF MEXICO... A stationary front is in Florida from 28N82W, into the south central Gulf of Mexico, to 23N97W. Precipitation: disorganized isolated moderate to locally strong spans the Gulf of Mexico. Gentle to moderate NE to E winds, and sea heights that range from 3 feet to 4 feet, are to the north of the front. Light to gentle winds, and sea heights that range from 2 feet to 4 feet, are to the southeast of the stationary front. A stationary front stretches from just N of Tampa Bay to 23N96W. This front will dissipate late tonight. Moderate to fresh return flow will develop across the NW Gulf tonight into Fri morning ahead of the next approaching cold front. This next front is expected to push off the Texas coast late Fri afternoon and move SE through the weekend. Strong N winds will follow the front W of 94W through Sat afternoon, with brief gales expected across the Veracruz area late morning Sat through the afternoon. The front is expected to reach the Florida Panhandle to central Bay of Campeche by Sun afternoon before stalling and gradually dissipating. ...CARIBBEAN SEA... Please, read the SPECIAL FEATURES section, for details about the potential for heavy rain in the eastern Caribbean Sea through at least Friday. A moist and unstable atmosphere will persist in the area through the weekend, due to a persistent upper level central Caribbean Sea trough and its interaction with a tropical wave. A surface trough passes through 31N70W to 26N70W, to 10N66W at the coast of Venezuela. Precipitation: widely scattered to scattered moderate and isolated strong is within 540 nm to the east of the surface trough, in the Atlantic Ocean and in the Caribbean Sea. Light to gentle NE winds are in most of the area that is from 70W westward. Moderate to fresh E to SE winds, and sea heights that range from 6 feet to 8 feet, are between 50W and the Lesser Antilles. Fresh to locally strong SE winds, and sea heights that range from 4 feet to 7 feet in E and SE swell, are in the eastern Caribbean Sea to the east of the tropical wave. 24-hour rainfall totals in inches, for the time period that ended at 27/1200 UTC, according to the Pan American Temperature and Precipitation Tables/MIATPTPAN, are: 2.50 in St. Thomas, 1.56 in Trinidad, 0.80 in San Juan in Puerto Rico. The monsoon trough is along 10N from Colombia along 74W, westward, beyond Panama and Costa Rica, and into the tropical NE Pacific Ocean. Precipitation: isolated moderate to locally strong is from 15N southward from 70W westward, in the SW corner of the Caribbean Sea. A deep layered upper trough N to S across the central Caribbean will drift westward tonight through Sat then lift northward into the Atlantic Sun. A tropical wave along 68W continues to interact with this feature to produce scattered to numerous thunderstorms between 63W and 68W this morning. The tropical wave will move slowly W through the weekend. An area of low pressure is expected to form over the eastern Caribbean Sea this weekend, possibly related to the southern portion of an existing trough of low pressure over the area. Thereafter, environmental conditions are forecast to be conducive for gradual development, and a tropical depression could form early next week while the disturbance moves generally westward or west-northwestward into the central Caribbean Sea. This system has a low chance of development in the next 48 hours and a medium chance in the next 5 days. ...ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section, for details about the convective precipitation that is associated with a 31N70W-to-10N66W surface trough. A cold front passes through 31N77W to the eastern coast of Florida near 28N80W. The rest of the front is stationary, from Florida into the Gulf of Mexico. Precipitation: rainshowers are possible within 240 nm to the east and southeast of the system. A surface trough passes through 31N70W to 26N70W, to 10N66W at the coast of Venezuela. Precipitation: widely scattered to scattered moderate and isolated strong is within 540 nm to the east of the surface trough, in the Atlantic Ocean and in the Caribbean Sea. A dissipating stationary front continues from 31N20W to 26N30W 25N40W 31N54W. The sea heights are at least 7 feet or higher from the stationary front northward from 40W eastward. The comparatively highest sea heights are ranging from 10 feet to 15 feet from 31N northward from 40W eastward. Light to gentle winds are in the wake of the front. Mainly moderate E to SE winds are between 47W and 52W. Precipitation: isolated moderate to locally strong is within 300 nm to the south of the dissipating stationary front. An upper level trough passes through 31N40W to 02N50W near the coast of South America. The upper level wind flow that is on the eastern side of the trough is pushing broken to overcast multilayered clouds into the area that is from 10N to the dissipating stationary front from 40W eastward. North swell, that is generated N of the dissipating stationary front will produce wave heights that will range from 8 feet to 12 feet, from 29N northward from 45W eastward, through tonight. Mainly moderate NE winds, and sea heights that range from 5 feet to 7 feet, are from 23N southward from 40W eastward. Fresh easterly winds, and sea heights that range from 5 feet to 8 feet, are in the tropical Atlantic Ocean between 48W and the Lesser Antilles. Scattered to numerous showers and thunderstorms persist across the Atlantic waters between 62W and 68W, supported by a deep layered upper trough along about 70W. At the surface, a trough of low pressure stretches from Hispaniola northward along 69W-70W. These features are expected to remain nearly stationary through early Sat and maintain active thunderstorms to the E. A surface low pressure system is forecast to emerge along the northern portion of the trough axis later today or tonight, and environmental conditions appear marginally conducive for some subtropical development. A subtropical depression could form during the next couple of days while the system moves northward, then meanders to the west or southwest of Bermuda. Over this weekend, upper-level winds are forecast to become less conducive for development. This system has a medium chance of development in the next 48 hours and 5 days. Associated large NE swell will impact the northern waters W of 70W Fri night through the weekend. $$ mt/ar