000 AXNT20 KNHC 291802 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Fri Mar 29 2024 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 1745 UTC. ...SPECIAL FEATURES... Central and Eastern Atlantic Significant Swell Event: Broad low pressure of 1009 mb is centered near 26N57W. Broad and persistent high pressure is present to its northeast and east. A very tight pressure gradient between the low and the high pressure has been sustaining a large fetch of fresh to strong southeast winds for the past several days. This synoptic set up has resulted in seas of 10 to 15 ft over the waters from 22N to 31N between 33W and a line from 31N61W to 22N50W with period 10- 17 sec. A recent altimeter satellite data pass indicated these seas. In the eastern Atlantic, a weakening cold front that extends from northern Africa southwestward to 23N20W and northwestward to near 25N33W. Significant north swell producing seas of 11 to 17 ft is north of the front east of 35W with period of 10-15 sec. The swell will gradually decay through Sat as the swell groups migrate south-southeastward. Please, read the latest High Seas Forecast at www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for more information. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends through the coastal plains of Sierra Leone near 08N13W southwestward to 01N19W, where latest scatterometer data indicates that it transitions to the ITCZ and continues to 02S26W and to near 02S43W. Numerous clusters of strong convection are emerging off the coast of Africa south of the trough to near 01S and east of 17W. Scattered moderate to isolated strong convection is northwest of the ITCZ from along and near the equator west of 37W to inland the coast of northeast Brazil and north to near 07N. ...GULF OF MEXICO... High pressure of 1025 mb analyzed over the northeast part of Alabama has a ridge that extends southwestward to the central and NW Gulf waters. The gradient between the ridge and a cold front that is southeast of the Gulf is allowing for fresh northeast winds to be over the southeastern Gulf. Winds elsewhere are gentle to moderate, northeast to east in direction over the central Gulf and fresh, southeast in direction, over the NW Gulf. Seas are in the range 3 to 6 ft, except for higher seas of 5 to 7 ft over the central Gulf and 6 to 8 ft seas over the southeastern Gulf. Satellite imagery shows no convection throughout the basin, instead mostly clear skies prevail under the high pressure that is in place. For the forecast, the aforementioned high pressure will shift eastward this weekend, with its associated gradient interacting with deepening low pressure in the southern Plains. This synoptic set up is expected to bring fresh east to southeast winds across the western Gulf Sat through Mon. Another cold front may enter the western Gulf by Tue increasing winds and seas west of the front. ...CARIBBEAN SEA... A dissipating cold front stretches from eastern Cuba to the northeast part of Honduras. Fresh to strong northeast winds are behind the front along with seas of 6 to 8 ft. Satellite imagery shows scattered showers and isolated thunderstorms within 90 nm west of the front from 16N to 18N. Isolated showers are elsewhere within 180 nm west of the front from 16N to 19N. With the front moving across the western Atlantic, this has caused the pressure gradient to weaken over the remainder of the basin. The tail-end of a central Atlantic trough reaches to near the northern Leeward Islands while another central Atlantic trough reaches to near the northern Windward Islands. Winds east of the front are northerly, light to gentle in speeds, except east of 65W they are mostly light, west to northwest in direction. North swell that has been impacting the Caribbean Passages continues to produce seas to around 5 or 6 ft in the eastern Caribbean through the weekend. Seas elsewhere east of the front are about 3 ft or less. For the forecast, the fresh to strong winds behind the front will follow the front across the remainder of the western Caribbean today. Winds and seas will diminish this afternoon. High pressure building north of the region in the wake of the front will support fresh to strong northeast winds in the lee of eastern Cuba and across the Windward Passage tonight through Sat evening. Winds and seas will then diminish by Sat evening. Moderate north swell that is propagating through the northeast Caribbean Passages and adjacent Tropical Atlantic waters will subside through early on Sat. Strong trade winds and rough seas will pulse off the coast of Colombia and the southern coast of Hispaniola this weekend as the high pressure settles to the northeast of the Bahamas. ...ATLANTIC OCEAN... Please read the Special Features section for information on a Significant Swell event that is impacting sections of the central and eastern Atlantic. A cold front is analyzed from near 31N67W to 26N71W and to eastern Cuba. A recent ASCAT satellite data pass reveals fresh to strong northwest to north winds west of the front north of 27N, and fresh north to northeast winds west of the front south of 27N. Seas behind the front are 9 to 14 ft in northwest to north of 27N and 8 to 12 ft in north to northeast swell south of 27N. To the southeast of the front, broad low pressure of 1009 mb is near 26N57W, with a trough extending northwest from it to 31N60W, and another trough extending from the low to 22N56W and southwestward to the northern Leeward Islands. A trough is to the east of these features from 31N54W to 20N55W and southwestward to the northern Windward Islands. Gentle to moderate west to northwest winds are between the troughs connected to the low pressure and the aforementioned cold front. Seas over these waters are 6 to 8 ft in northeast to east swell. Recent ASCAT satellite data passes indicate fresh to strong southeast winds north of 20N between 46W-52W. Within this area of fresh to strong winds, the ASCAT data has near gale southeast to south winds from 22N to 26N between 48W and 51W, and also from 23N to 26N between 41W and 48W. Seas as described above under Special Features. A broad area of rather persistent high pressure continues to be the main feature controlling the wind pattern regime over the eastern Atlantic and the eastern part of the central Atlantic areas. The high pressure is anchored by a 1027 mb center that is north of the area near 34N40W. Latest ASCAT satellite data passes reveal mostly fresh trade winds from 03N to 22N between 20W and 41W. Seas over these waters are in the range of 6 to 8 ft. S of 03N and east of 46W, trade winds are light to gentle in speeds with seas of 5 to 7 ft. For the forecast W of 55W, broad low pressure located to the southeast of Bermuda near 26N57W will meander then weaken to a trough this afternoon while it slowly moves east of 55W tonight. Farther west, a cold front extends from near 31N67W to 26N71W and to eastern Cuba will reach from near 31N55W to the Mona Passage by Sat morning, then move east of the area early Sun. Strong winds and rough seas will follow this front. Winds and seas will decrease from west to east this weekend as high pressure builds eastward in the wake of the front. $$ Aguirre