AXNT20 KNHC 230803 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Apr 23 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 0600 UTC surface analysis and satellite imagery through 0730 UTC. ...SPECIAL FEATURES... Central Atlantic Gale Warning: Low pressure, 1005 mb, is analyzed near 29.5N34.5W with an occlusion and then trailing cold front wrapping around it through 31N28W to 22N30W to 17N39W. Scattered showers and thunderstorms are possible N of 25N within 60 nm NE of the front. Gale-force winds were measured by an earlier ASCAT scatterometer pass, and a gale warning is in effect for the waters N of 28N between 34W and 38W. Large seas up to 15 to 17 ft will accompany the gale winds, with a large surrounding area of fresh to strong winds and seas of 8 ft or greater. The low will gradually weaken during the next couple of days as it shifts SSW. Gale conditions will diminish this afternoon, then fresh to strong winds will diminish early Thu. Seas will finally subside to less than 8 ft by early Fri. Please read the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes to the coast near the border of Guinea and Sierra Leone near 09N13W, extending southwestward to 03N20W. The ITCZ extends from 03N20W to 02S31W to just off the coast of northern Brazil at 02S43W. Scattered moderate isolated strong convection is noted along and S of the Equator between 24W and 40W, and S of 03N between 45W and 50W. ...GULF OF MEXICO... A dissipating stationary front extends from the Straits of Florida through 23N89W to the SW Gulf. A surface trough was captured by and earlier ASCAT scatterometer pass just offshore of Veracruz, Mexico supporting fresh winds and seas to 7 ft W of the trough. Mainly moderate to locally fresh winds are in the wake of the front, along with subsiding 4 to 7 ft seas, except 2 to 4 ft N of 27N. For the forecast, the front will wash out today. A trough offshore of Veracruz will dissipate later today. Otherwise, high pressure will build in the wake of the front, supporting mainly gentle to moderate winds in the NE half of the Gulf, and moderate to fresh winds in the SW half of the Gulf through Thu. The pressure gradient will tighten over the Gulf by the end of the week, increasing winds to fresh to strong across the basin. Seas will build as a result. Meanwhile, fresh to strong winds will pulse NW of the Yucatan during the evenings. ...CARIBBEAN SEA... A weak pressure gradient prevails over the basin supporting mainly gentle to moderate trades, locally fresh S of 15N and E of 74W, and also in the lee of Cuba. Seas are 3 to 5 ft in the S-central and SE waters, and 2 to 4 ft elsewhere, except 1 to 3 ft in the NW Caribbean. A surface trough extends through the Mona Passage with nearby scattered showers and isolated thunderstorms. For the forecast, broad high pressure north of the area will support mainly gentle to moderate trades through early Wed, locally fresh near the Windward Passage and S-central Caribbean. The pressure gradient will increase through the day Wed, with moderate to locally fresh trades dominating the basin through the end of the week and into the weekend. Winds will pulse to fresh to strong in the S-central Caribbean and near the Windward Passage Wed evening and night, and in the Lee of Cuba Thu night. Similar winds are possible S of Hispaniola, near the Windward Passage, in the Lee of Cuba, and near the Gulf of Honduras Sat night. Slight to moderate seas will prevail through the next several days. ...ATLANTIC OCEAN... Please read the Special features section for information on gale conditions in the central Atlantic near 31N35W. A cold front extends from 31N70W to the Straits of Florida. A line of showers and thunderstorms is observed within 120 nm ahead of the frontal boundary, mainly N of 27N. Gale-force winds have lifted N of the 31N as indicated by an earlier ASCAT scatterometer pass, with lingering fresh to strong winds N of 29N between 66W and 77W. Seas of 8 to 12 ft in northerly swell covers the waters W of the front, with hazardous seas between the Bahamas and Florida across the Gulf Stream. A surface trough is analyzed from through the Mona Passage to N of Puerto Rico supporting nearby scattered showers and isolated thunderstorms. Away from the low discussed in the Special Features section, ridging dominates the remainder of the waters W of 35W with mainly gentle to moderate trades, locally fresh S of 22N between 40W and 65W. Seas are mainly 4 to 7 ft, except 3 to 5 ft N of 22N between 45W and ahead of the front. E of 35W and away from the low, mainly light to gentle winds and 3 to 5 ft seas prevail, except moderate winds N of 10N west of Africa to 20W. For the forecast west of 55W, fresh to strong winds associated with the cold front N of 29N on either side of the front will lift N of the area by the afternoon. Associated seas of 8 ft or greater behind the front will subside by Wed evening. The front will reach from 31N64W to the SE Bahamas this evening while weakening, then will become a dissipating stationary front from 31N59W to 21N76W Wed evening, then becoming a remnant trough there by Thu evening. The trough will linger through the end of the week, getting reinforced by a cold front which may dive S of 31N Fri night, reaching from 31N54W to near N Haiti by Sat evening. Increasing winds to fresh to strong W of the boundary will prevail by Sat evening along with a rapidly building area of large seas. The aforementioned surface trough near Puerto Rico triggered showers and thunderstorms since yesterday afternoon with total rainfall accumulation between 2 to 4 inches. The wet pattern over Puerto Rico will persist through the week, maintaining elevated potential for flooding, excessive runoff, and landslides. Please refer to the National Weather Service San Juan for more details about possible flood advisories and warnings in the upcoming days. $$ Lewitsky