000 AXNT20 KNHC 081812 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sat Apr 08 2023 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 1750 UTC. ...SPECIAL FEATURES... SW NORTH ATLANTIC OCEAN GALE-FORCE WIND WARNING AND LARGE NE SWELL EVENT: A strong cold front is expected to move offshore of the SE U.S.A. and NE Florida, from today through Sunday. The strong cold front will move southeastward. The front will reach from near Bermuda to central Florida on Sunday evening, and from 31N60W to SE Florida by Monday evening. A large area of strong to gale-force N to NE winds, and very large seas, will build behind the front by Sunday evening. The large seas will spread across the waters that are from 26N northward from 65W westward by Tuesday. These high seas, and strong to gale-force winds, will extend westward, all the way to the east coast of Florida from Sunday afternoon through Monday night. The Ocean Prediction Center has issued a storm-force wind warning for the conditions that will be happening to the north of 31N during this event. The sea heights are expected to reach 20 feet near 31N75W on Sunday night. The NE swell will continue to produce sea heights of 12 feet and greater through Tuesday evening. Please, read the latest High Seas Forecast, that is issued by the National Hurricane Center, at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Sierra Leone, to 03N21W. The ITCZ continues from 03N21W, to the Equator along 28W, to 02S39W, to the Equator along 48W. Precipitation: widely scattered moderate to isolated strong is from 08N southward from 40W eastward. Isolated moderate to locally strong is elsewhere from 10N southward from 60W eastward. ...GULF OF MEXICO... A stationary front passes through NE Florida, through the coastal plains and the coastal waters of the U.S.A. Gulf of Mexico coast, curving to a 25N95W 1014 mb low pressure center. The stationary front eventually continues to the coast of the Isthmus of Tehuantepec of southern Mexico, near 18N95W. Precipitation: widely scattered moderate to isolated strong is to the west of the line that extends from the Tampa Florida metropolitan area, to the central Gulf of Mexico, into the SW corner of the Gulf of Mexico Winds have been fresh to strong offshore Tamaulipas and Veracruz, Mexico, and moderate to fresh elsewhere W of the front. Seas are 5-8 ft W of the front. Moderate to fresh winds are offshore the western sections of the Yucatan Peninsula. Gentle to moderate winds and 4-6 ft seas prevail elsewhere, except 1-3 ft seas in the far NE Gulf. A stationary front lingers from near New Orleans in Louisiana to weak low pres near 25.5N94.5W to the western Bay of Campeche near 18.5N95W. The front will move slowly eastward over the western half of the Gulf through Sun. Fresh to locally strong northerly winds are expected off Veracruz through this evening. Another low pres, expected to develop just off the SE coast of United States tonight, will allow a cold front to move southward over Florida and the NE Gulf on Sun. Fresh to locally strong E winds are expected behind the front in the N-central and NE Gulf through mid-week. Low pres will develop along the remnants of the front in the N central Gulf Tue and deepen through Wed. ...CARIBBEAN SEA... Broad upper level cyclonic wind flow covers the Atlantic Ocean and the Caribbean Sea from 10N northward between 50W and 80W. Precipitation: widely scattered moderate to isolated strong is from 17N in the Caribbean Sea to 30N in the Atlantic Ocean between 59W and 75W, including in the Caribbean Sea islands. Earlier heavy rainfall prompted flash flood warnings in parts of eastern Puerto Rico this morning. Fresh to strong NE winds are just offshore in the S-central Caribbean, as well as in the SE Caribbean. Moderate to fresh winds are elsewhere in the central and eastern Caribbean, as well as in the lee of Cuba, with moderate NE-E winds across the remainder of the basin. Seas are 4-7 ft in the central and eastern Caribbean, and 3-5 ft in the western Caribbean. The gradient between subtropical high pressure, and lower pressure in the SW Caribbean Sea, is supporting fresh to strong NE to E winds through the Windward Passage, to the south of Hispaniola, in the Gulf of Honduras, in the lee of eastern Cuba, and in the south central Caribbean Sea. Fresh easterly trade winds are in the eastern Caribbean Sea. Moderate winds are in the rest of the western Caribbean Sea. Seas are in the 6-9 ft range in the central Caribbean, 6-8 ft from the lee of the Windward Passage to NE Jamaica and mainly 4-6 ft elsewhere. A broad inverted trough from near 16N71W across central Hispaniola and N-NE into the Atlantic is accompanied by very active weather. The trough will shift W and into the SE Bahamas and eastern Cuba while weakening through Sun night. Atlantic high pressure will build modestly across the basin behind the trough and allow for fresh to strong winds in the S-central Caribbean to pulse at night through the next several days. Winds and seas in the eastern Caribbean and Tropical N Atlc E of the trough will gradually diminish through Sun. Weak high pressure will then prevail N of the area Mon through Wed ahead of a strong cold front that will move across the NW Atlantic. ...ATLANTIC OCEAN... Broad upper level cyclonic wind flow covers the Atlantic Ocean and the Caribbean Sea from 10N northward between 50W and 80W. Multiple individual upper level cyclonic circulation centers are in the area of broad upper level cyclonic wind flow, mostly between 58W and 75W. An inverted surface trough is in the Atlantic Ocean along 29N67W 23N70W 16N71W. Precipitation: widely scattered moderate to isolated strong is from 17N in the Caribbean Sea to 30N in the Atlantic Ocean between 59W and 75W, including in the Caribbean Sea islands. The inverted surface trough is moving through broad surface anticyclonic wind flow in the Atlantic Ocean. W of the trough axis, winds are moderate from the NE-E, with seas of 4-7 ft. E of the trough axis, winds are fresh from the E-SE, with 6-10 ft seas S of about 27N and W of 40W. A central Atlantic 1024 mb high pressure center is near 31N52W. Gentle to moderate winds are N of 25N. Similar winds prevail in the remainder of the open Atlantic waters. Seas of 7-9 ft in NW-N swell are N of 29N between 28W and 42W, associated a 31N22W-to-28N30W cold front. A surface trough continues from 28N30W 28N36W 26N37W 25N43W. Seas of 4-7 ft prevail in the remainder of the open Atlantic waters. A broad inverted trough accompanied by very active weather extends from near 29N67W to central Hispaniola, and will continue to shift W and weaken through Sun night, while reaching the central Bahamas. Atlantic high pres is drapped across the waters N of the trough, and is producing fresh winds and seas to 10 ft E of the trough. Winds and seas across the region will gradually diminish through Sun as the high pres weakens. A strong cold front is expected to move offshore of the SE U.S. and NE Florida today through early Sun, and sink SE across NW portions, reaching from near Bermuda to central Florida Sun evening, and from 31N60W to SE Florida by Mon evening. A large area of strong to gale-force N to NE winds, storm-force just N of 31N, and significant NE swell will build into the area behind the front, spreading across the waters N of 26N and W of 65W by Tue. The front may stall along 25N/26N by the middle of next week. $$ mt