000 AXNT20 KNHC 311059 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon Jul 31 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 0600 UTC surface analysis and satellite imagery through 1040 UTC. ...SPECIAL FEATURES... Central Tropical Atlantic Gale Warning (Invest AL96): A 1011 mb low pressure is centered near 22N52.5W. Numerous moderate isolated strong convection is noted within 270 nm in the eastern semicircle. Earlier ASCAT passes from late Sunday evening showed gale force winds to 35 kt in the eastern semicircle, within the convection. Peak seas are estimated at 13 ft. Environmental conditions are forecast to be marginally favorable for development over the next few days, and a tropical depression or tropical storm is likely to form during the next day or so. The system is expected to move northwestward at about 10 to 15 kt today, and then turn northward over the central subtropical Atlantic by late tonight or Tuesday. There is a high chance of tropical cyclone development of this system through the next 48 hours. During the next 48 hours, this system is forecast to produce winds of 35 to 40 kt and seas of 12 to 16 ft. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is analyzed in the eastern Atlantic with its axis near 30W from 04N to 20N, moving westward at around 15 kt. Scattered moderate convection is within 360 nm E of the wave axis from 07.5N to 12N. An eastern Caribbean tropical wave extends from St. Kitts and Nevis to Venezuela near 10N64W and inland to 03N64W, moving W at 10 to 15 kt. Scattered moderate isolated strong convection is noted within 60 nm either side of a line from 18N57W to 15N67W, including Guadeloupe, Antigua, Montserrat and St. Kitts and Nevis. Scattered moderate convection is also affecting portions of the ABC Islands. A western Caribbean tropical wave is located along 82W from 22N southward to western Panama, moving W at around 15 kt. Isolated showers and tstorms are noted near the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 19N16W to 08N41W. Aside from the convection described above, isolated moderate convection is noted along and within 120 nm S of the monsoon trough between 33W and 41W. GULF OF MEXICO... Scattered showers and thunderstorms are noted over portions of the northeastern Gulf of Mexico. Similar activity is seen over the western Straits of Florida to north of the Yucatan Channel. Moderate convection also covers a small area in the southern Bay of Campeche, south of 19.5N between 95W and 96W. Otherwise, high pressure ridging prevails across the northern Gulf, anchored by a 1018 mb high pressure near 28N89W. This is leading to light to gentle winds across the basin with seas 1 to 3 ft. For the forecast, the surface ridge will remain the dominant feature across the basin through early this week. This will support gentle to moderate winds, except over the eastern Bay of Campeche during the middle to latter part of the week, where winds will be enhanced by a thermal trough that will emerge off the Yucatan Peninsula each night. High pressure will shift SE into the east Gulf Tue and Wed and allow for moderate return flow to develop across the W Gulf Wed through Fri. CARIBBEAN SEA... Please refer to the Tropical Waves section above for information on the waves moving across the Caribbean. The east Pacific monsoon trough is inducing scattered strong convection across eastern Panama, NW Colombia, and the waters south of 11.5N between 75W and 80W. Fresh to strong trade winds continue across the central Caribbean with seas 7 to 8 ft. Mainly moderate winds prevail elsewhere with 3-6 ft seas. For the forecast, the pressure gradient between high pressure ridging north of the area and lower pressure over Colombia will maintain fresh to strong trades across the central Caribbean through this morning. A 1011 mb low pressure near 22N52.5W is expected to move NW into the open Atlantic through Wed, disrupting the ridging N of the area. As this occurs, winds will diminish slightly across the Caribbean, and the fresh to locally strong winds will be confined to the south-central Caribbean. ATLANTIC OCEAN... Please refer to the Special Features section for details on low pressure well NE of the Leeward Islands that has potential for tropical development. Elsewhere, scattered showers and isolated thunderstorms prevail across the western Atlantic, west of 67W through the northwest Bahamas area. A surface ridge extends from 31N57W to 26N66W to the southern tip of Florida. To the north of the ridge, moderate to fresh SW winds are present north of 30N between 65W and 75W, where seas are 4 to 6 ft. Fresh trades and 4-5 ft seas are also present north of Hispaniola and within the Windward Passage. Mainly gentle winds and 3-4 ft seas prevail elsewhere over the western Atlantic. East of 60W, AL96 is affecting waters from 20N to 27N between 46W and 55W. A 1027 mb high pressure centered near 34.5N37W dominates the remainder of the waters. Fresh trades are in the E Atlantic from 16N to 27N with seas 5 to 7 ft. Fresh to strong NE winds extend from the coast of Morocco through the Canary Islands with seas 6 to 8 ft. For the forecast west of 55W, the aforementioned high pressure centered SW of the Azores will gradually shift E-NE through the week. Moderate to locally fresh trade winds will continue S of 23N through early Tue before diminishing. Fresh trades will pulse during the afternoon through early evening today and Tue N of Hispaniola and over the Windward Passage. A gale force 1011 mb low pressure across the central Atlantic near 22N52.5W will move NW then N and brush the NE offshore zones tonight through early Wed, likely as a tropical cyclone, before exiting the region to the N, which will act to disrupt the Atlantic ridge. A weak frontal trough will sink S into the waters offshore of NE Florida Tue night and move SE and reach from near Bermuda to the northwest Bahamas by Thu. $$ Hagen