000 AXNT20 KNHC 162232 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Jul 17 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 1800 UTC surface analysis and satellite imagery through 2215 UTC. ...TROPICAL WAVE... A central Atlantic tropical wave has its axis along 42W from 04N to 20N moving westward at 10-15 kt. Isolated small showers are near the wave axis south of 09N. The remainder of the wave is surrounding Sahara Air Layer dust that is inhibiting convection. An eastern Caribbean Sea tropical wave has its axis along 63W south of 21N. Its is moving westward at 15 to 20 kt. Isolated showers and thunderstorms are over water within 60 nm either side of the wave south of 14N. Scattered showers and thunderstorms are within 60 nm west of the wave over Venezuela from 09N to 11N. The tropical wave that earlier had its axis along 89W south of 19N moved inland Central America this morning. Its southern portion extends into the eastern Pacific. Please refer to the eastern Pacific Tropical Weather Discussion for details on this wave. ...MONSOON TROUGH/ITCZ... The monsoon trough reaches the eastern Atlantic through the coast of NW Mauritania near 21N17W and continues southwestward to 10N29W, to 10N43W and northwestward to near 14N52W. An ITCZ is analyzed south of the monsoon trough from 05N39W northwestward to 07N50W and to near 12N60W. Scattered moderate convection is within 60 nm south of the trough between 26W and 30W, between 35W and 38W. Similar activity is within 60 nm south of the ITCZ between 57W and 58W and between 59W and 60W. ...GULF OF MEXICO... Relatively weak high pressure is present over the basin as a weak 1019 mb high center is analyzed at 29N87W. The associated gradient is supporting a generally light to gentle anticyclonic wind flow. Seas as observed in the latest buoy reports and as seen in a recent altimeter satellite data pass are in the slight range. A surface trough extends from northeast Florida southwestward to Tampa, Florida and to the eastern Gulf near 25N85W. Increasing scattered showers and thunderstorms are along and within 60 nm west of the trough from 25N to 28N. Similar activity is over the interior portions of central and SW Florida. The atmosphere remains very moist and unstable throughout supporting scattered showers and isolated thunderstorms over waters north of 25N. For the forecast, weak pressure ridging will extend from the Atlantic westward over the northern Gulf of Mexico into the weekend, supporting moderate or weaker winds and mainly slight seas. Scattered showers and thunderstorms may move offshore of western Cuba into the lower Straits of Florida and over a portion of the southeastern Gulf this evening accompanied by possible gusty winds and rough seas. ...CARIBBEAN SEA... The pressure gradient between higher pressure over the west- central Atlantic and relatively lower pressures in South America is allowing for fresh trade winds in the south-central part of the sea to near the coast of Colombia. A pocket of fresh to strong NE trade winds is embedded within the fresh winds from 11N to 13N between 75W and 77W as noted in the most recent ASCAT satellite data pass across this part of the sea. Seas over these waters are in the 7 to 10 ft range. Seas of 4 to 7 ft are over the north-central Caribbean. Moderate or weaker winds and slight to moderate seas are prevalent elsewhere in the basin. Scattered showers and thunderstorms are developing over the northwest part of the sea north of 19N, including sections of western Cuba. For the forecast, the pressure gradient between an Atlantic high pressure ridge extending along 30N-31N and lower pressure across South America will continue to sustain fresh to strong trade winds over the central Caribbean before diminishing slightly Thu through Fri night. ...ATLANTIC OCEAN... A surface trough extends from near 31N27W southwestward to 25N60W. No significant convection is occurring with this trough. Another trough extends from near 31N62W southwestward to near 25N70W. An upper-level low moving westward is identified on water vapor imagery near 26N68W. Scattered showers and isolated thunderstorms are noted from 22N to 29N between 64W and 68W. Otherwise, a 1026 mb high center is analyzed near 31N49W. A ridge stretches west-southwestward from the high to central Florida, and continues westward across the Gulf of Mexico. The pressure gradient between the aforementioned ridge and lower pressures in the deep tropics is sustaining moderate to locally fresh easterly winds from 15N to 24N and between 38W and 60W. Seas over these waters are 4-7 ft. Elsewhere, moderate or weaker winds and slight to moderate seas prevail. For the forecast west of 55W, the Bermuda high pressure ridge will extend west-southwestward to Central Florida into the weekend. Winds are forecast to increase to fresh over the southeastern waters Wed night through early Fri as the high pressure drifts westward and strengthens some, and a tropical wave moves through tropical Atlantic waters. Look for winds to pulse to fresh to strong each evening offshore of the N coast of Hispaniola Thu through Sat. $$ Aguirre