000 AXNT20 KNHC 122250 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sat Aug 13 2022 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 2230 UTC. ...TROPICAL WAVES... A tropical wave is analyzed with axis along 19W, from 20N southward, moving W at 10-15 kt based on 700 mb wind speeds. A 1008 mb low pressure is along the wave axis near 14N19W. Scatterometer data depicts moderate to fresh winds in the vicinity of the wave axis. Scattered moderate convection, enhanced by the Monsoon Trough, is west of the wave axis from 07N to 18N and E of 29W. A tropical wave extends its axis along 51W from 23N southward, moving westward at 15-20 kt. Scattered showers are noted in the vicinity of the wave axis, mainly where it meets the monsoon trough. A tropical wave approaching the Lesser Antilles arc, with axis extending along 60W from 21N southward, moving westward at 10-15 kt. No significant convection is noted over the waters at this time. A tropical wave located in the central Caribbean is along 74W, from 21N southward, moving westward at 10-15 kt. Scattered moderate convection is east of the wave axis, from 16N to 20N between 67W and 74W, affecting Hispaniola and La Mona Passage. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Senegal near 16N17W to 1008 mb low pressure near 14N19W to 11N38W to 10N60W. Aside from the convection described in the Tropical Waves section above, scattered showers prevail from 07N to 19N between 41W and 59W. GULF OF MEXICO... 1014 mb low pressure is centered in the NW Gulf near 29N92W, with a trough extending from 30N91W to 25N97W. These features, combined with broad surface convergence across the northern Gulf, is producing scattered moderate convection across the northern half of the basin north of 24N. Winds and seas may be locally higher in the convection. Elsewhere in the Gulf of Mexico, gentle to moderate SE to S winds prevail along the periphery of the subtropical Atlantic ridge, with seas of 2-4 ft. For the forecast, the weak Atlantic high pressure will sink southeast through Tue. This will allow for gentle to moderate winds over the basin to weaken to light to gentle into next week. Moderate NE to E winds will pulse to fresh during the late afternoon and evenings off the NW Yucatan peninsula through early next week. Scattered to numerous showers and thunderstorms associated with a low pressure trough and weak low pressure that is along it are over most of the northern Gulf waters. This system will drift west-southwestward over the NW Gulf and toward the Texas coast during the weekend. Development, if any, of this system is expected to be slow to occur. Strong gusty winds and rough seas can be expected with this activity. Meanwhile, a weak frontal boundary is expected to stall just north of the central and NE Gulf during the weekend. CARIBBEAN SEA... Refer to the section above for details on the tropical waves moving across the basin. The latest scatterometer data depicts gentle to moderate trades in the eastern and central Caribbean, with light to gentle trades in the western Caribbean. A 1010 mb Colombian/Panamanian low is in the SW Caribbean near 12N83W, along the extension of the East Pacific Monsoon Trough. Scattered moderate convection is to the northwest of the low, from 11N to 14N west of 81W including coastal regions of Nicaragua. For the forecast, the Atlantic high pressure will drift southward and weaken through early next week. Moderate to fresh trade winds over the central Caribbean will weaken to moderate Sat through Mon, then increase to fresh late Mon through Tue night. A broad surface trough accompanies a tropical wave across the central Atlantic, and is expected to move across the Tropical N Atlantic tonight night through Sat night, across the eastern Caribbean early Sun through early Mon, across the central Caribbean Mon through late Wed. ATLANTIC OCEAN... Refer to the section above for details on the tropical waves moving across the basin. An outflow boundary is analyzed in the deep tropics, from 14N41W to 10N43W, moving west at 15-20 kt. E winds to 30 kt were captured well in scatterometer data this morning behind this boundary. The remainder of the tropical Atlantic continues to be dominated by the subtropical ridge located north of the area. NE to E winds are gentle to moderate across the basin, except from 18N to 24N east of 30W where NE winds are fresh. Seas are 3-5 ft north of 19N and west of 55W, and 5-7 ft elsewhere in open waters. Seas are locally 8 ft NE of the Cabo Verde Islands. For the forecast W of 55W, the ridge that extends from the central Atlantic WSW to northern Florida along 29N, will weaken and sink southward through early next week as a frontal boundary moves off the eastern seaboard and begins to weaken as it stalls from across NE Florida east-northeastward to north of 31N78W. Moderate to fresh E winds S of 25N will veer to the SE and weaken to gentle early Sat and change little into next week. Light to gentle variable winds are expected elsewhere through the period. A tropical wave will reach the southeast forecast waters by early Sat, bringing a slight increase in winds and seas over those waters through early Mon. A cold front may move over the waters northeast of NE Florida late Tue, then stall and weaken through Wed night. $$ ERA