000 AXNT20 KNHC 151804 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sat Jul 15 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 1740 UTC. ...SPECIAL FEATURES... The center of Subtropical Storm Don, at 15/1500 UTC, is near 36.5N 48.8W. Don is moving toward the NW, or 325 degrees, 08 knots. The estimated minimum central pressure is 1006 mb. The maximum sustained wind speeds are 40 knots with gusts to 50 knots. Tropical storm-force winds are within 150 nm of the center in the NE quadrant; within 80 nm of the center in the SE quadrant; within 0 nm of the center in the SW quadrant; and within 0 nm of the center in the NW quadrant. The sea heights are 12 feet or higher within 210 nm of the center in the NE quadrant; within 180 nm of the center in the SE quadrant; within 0 nm of the center in the SW quadrant; and within 180 nm of the center in the NW quadrant. The maximum sea heights are reaching 18 feet. Precipitation: widely scattered moderate to isolated strong is from 34N to 40N between 45W and 52W. Please, read the latest HIGH SEAS FORECAST, that is issued by the Ocean Prediction Center, at the web-site https://www.opc.noaa.gov/text/MIAHSFAT1.shtml, and the latest Subtropical Storm Don Forecast/Advisory and the Public Advisory, at www.hurricanes.gov for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 20W, from 17N southward, moving westward from 10 knots to 15 knots. Precipitation: isolated moderate to locally strong is from 04N to 14N between Africa and the 20W tropical wave. An Atlantic Ocean is along 47W/48W, from 18N southward, moving westward from 15 knots to 20 knots. A dry Saharan airmass has enveloped the wave. Precipitation: broken to overcast multilayered clouds, and possible rainshowers, are from 17N southward between 40W and 50W, at the western end of the ITCZ. The sea heights range from 4 feet to 6 feet in the remainder of the area that is from 20N southward. A Caribbean Sea tropical wave is along 61W/62W, from 19N southward, moving westward from 15 knots to 20 knots. Precipitation: scattered strong is from 12N to 14N between 62W and 66W. Broken to overcast multilayered clouds, and widely scattered moderate to isolated strong is elsewhere from 15N southward between 58W and 70W. Broken to overcast multilayered clouds also are from 17N southward between 60W and 73W. Mostly fresh to some strong winds are 19N southward between 54W and 66W, including in the eastern parts of the Caribbean Sea. The sea heights range from 4 feet to 6 feet from 70W eastward. A Caribbean Sea tropical wave is along 83W/84W, from 22N southward, moving westward from 10 knots to 15 knots. Precipitation: numerous strong is from 11N to 13N between 82W and 85W, at the coast of Nicaragua. Isolated moderate to locally strong is elsewhere within 360 nm on either side of the tropical wave. Dense upper level clouds are within 60 nm on either side of the line 11N81W 13N76W 14N72W. Moderate to fresh winds, and sea heights that range from 3 feet to 5 feet, are from Honduras northward from 80W westward. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Mauritania from 18N to 19N along 16W, to 15N20W 10N26W 07N42W. The ITCZ is along 09N49W 10N59W. Precipitation: scattered moderate to widely scattered strong is within 100 nm of the monsoon trough on the northern side, between 27W and 30W. Isolated moderate to locally strong is from 08N to 13N between 23W and 33W. Broken to overcast multilayered clouds, and other possible rainshowers are in the remainder of the area that is from 15N southward from 40W eastward. GULF OF MEXICO... A surface ridge passes through 31N71W, through South Florida, to 27N78W, toward the upper Texas Gulf coast. The sea heights range from 1 foot to 2 feet from the coastal waters of Louisiana to the NE corner of the Yucatan Peninsula. The sea heights range from 3 feet to 4 feet elsewhere. Moderate or slower wind speeds span the area. A ridge will persist from southwest Florida to the central Texas coast through mid week, while a trough will develop over the Yucatan Peninsula each evening and move offshore. This pattern will maintain moderate to fresh winds pulsing north and west of the Yucatan Peninsula during the late afternoon and evening hours. Elsewhere, gentle to moderate winds and slight seas will prevail. CARIBBEAN SEA... One tropical wave is in the eastern part of the Caribbean Sea. A second tropical wave is in the western part of the area. Please, read the TROPICAL WAVES section, for details about the precipitation, the wind speeds, and the sea heights. Near gale-force winds are within 180 nm of the coast of Colombia between 73W and 78W. Mostly strong NE to some fresh winds, and sea heights that range from 7 feet to 10 feet, cover much of the central Caribbean Sea. A tropical wave that extends from just south of the western tip of Cuba to across southern Costa Rica will move across the remainder of the Caribbean through late today. Another tropical wave currently moving across the Lesser Antilles will move through the southeastern Caribbean today, then weaken as it moves across the central Caribbean through late Sun and across the western Caribbean late Mon. A third tropical wave will move into the eastern Caribbean from late Sun into Mon, then move across the central Caribbean during Mon and Mon night, and the western Caribbean Tue. The passage of the tropical waves will modulate fresh to strong winds across mainly the central Caribbean through the period. ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section, for information about Subtropical Storm Don in the central Atlantic Ocean near 36.5N 48.8W, at 15/1500 UTC. A surface ridge passes through 31N71W, through South Florida, to 27N78W, toward the upper Texas Gulf coast. A trough from 500 mb to 700 mb is in the SE U.S.A. Precipitation: widely scattered moderate to isolated strong is to the west of the line that runs from 31N65W to the coast of Cuba that is along 80W. Broad surface anticyclonic wind flow covers the Atlantic Ocean from 20N northward from 40W eastward. Mostly strong NE winds, and sea heights that range from 7 feet to 10 feet, are in this same area. Near gale-force NE winds are from 26N northward from 23W eastward. The sea heights range from 4 feet to 6 feet in the remainder of the Atlantic Ocean. Fresh NE winds are from 14N to 23N between 40W and 55W. Variable fresh winds are from 13N southward from 30W eastward. Moderate or slower wind speeds cover the remainder of the Atlantic Ocean. High pressure will persist east of the Bahamas along 25N through Sun, supporting pulses of fresh to strong NE to E winds and rough seas off Hispaniola. The ridge will shift northward into Mon ahead of a tropical wave that will be approaching the area from the east. Looking ahead, the northern part of the tropical wave will move westward south of 22N into mid week. $$ mt/ja