844 AXNT20 KNHC 230528 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 128 AM EDT Mon Jul 23 2018 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 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...TROPICAL WAVES... A tropical wave is moving across the far east Atlantic with axis extending from 09N to 23N along roughly 26W, moving W at 10-15 kt. A large area of Saharan dust is noted along the wave mainly north of 10N. Scattered showers are noted where the tropical wave intersects the monsoon trough off the coasts of Sierra Leone and Guinea, from 07N to 10N east of 12W. A tropical wave is in the central Atlantic with axis extending from 08N-23N along 44W, moving W at 10-15 kt. This tropical wave continues to be on the leading edge of a large area of Saharan dry air and dust, inhibiting large scale convection at this time. Isolated cells are noted on the southern end of the tropical wave where it intersects the monsoon trough. A tropical wave is in the western tropical Atlantic with axis extending from 10N-24N along 58W, moving W at 10-15 kt. The tropical wave is accompanied by Saharan dry air and dust, inhibiting convection. A low amplitude and low latitude tropical wave is moving across the south central Caribbean and the Pacific coast of Colombia and adjacent waters, along 81W and south of 11N. The tropical wave may be interacting with overnight drainage flow to support a large area of showers and a few thunderstorms off the Gulf of Panama. A tropical wave extends across southern Mexico and the EPAC waters along 95W and south of 18N. Scattered showers are noted along the wave's axis over Mexico. A larger area of convection is observed over the EPAC waters with this feature. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 18N16W to 08N42W. The ITCZ extends from 08N46W to 05N54W. Scattered moderate convection is noted from 05N-09N between 34W-42W. ...DISCUSSION... GULF OF MEXICO... A surface trough moving across the Florida Panhandle enhancing scattered moderate convection that will continue moving south reaching the far northeast Gulf waters overnight. The remainder of the basin is under the influence of a surface ridge, anchored by a 1015 mb high centered near 23N90W. This feature is maintaining fair weather, light to gentle winds, and 1 to 3 ft seas across the basin. The surface trough over the northeast Gulf will be followed by a weak cold front that will move over the northern Gulf waters early this week. This front will become stationary and weaken quickly through the week. A surface trough will move off the Yucatan Peninsula into the Bay of Campeche each evening, accompanied by fresh nocturnal winds. Elsewhere, surface ridging will prevail. CARIBBEAN SEA... The northern portion of a tropical wave will is moving across the far southwestern Caribbean today, just north of Panama. This may bring increased showers and thunderstorms especially tonight, from the central coast of Panama to Costa Rica. Dry conditions persist elsewhere. Earlier scatterometer pass indicated fresh to strong trade winds over the south central Caribbean, mainly off Colombia. Maximum seas are estimated to be 8 to 10 ft. Seas are 3 to 5 ft in the northwest Caribbean, and 5 to 7 ft elsewhere. A tropical wave is approaching 58W, and will enter the east Caribbean today. While Saharan dry air and dust are inhibiting showers and thunderstorms, there may be isolated showers at least in the Windward Islands as the tropical wave moves into the region. Little change is expected elsewhere. ATLANTIC OCEAN... Three tropical waves are moving across the basin. Refer to the section above for details. Scattered showers and thunderstorms are ongoing over the northern Bahamas and adjacent waters, related to divergent flow aloft. Gusty winds are possible with these thunderstorms. Moderate S to SW winds are noted west of 70W with 4 to 6 ft seas in open waters. A broad high prevails across the remainder of the basin, centered near 41N48W. For the forecast, the Atlantic high pressure along with the low pressure system over the southeast U.S. will continue to produce moderate to fresh southerly winds across the waters just offshore the central and northeast Florida through Wed. Moderate to fresh winds are also expected south of 22N, including approaches to the Windward Passage. Ridging will dominate the area most of the forecast period, with a surface trough reaching the E part of the region by Thu. For additional information please visit http://www.hurricanes.gov/marine $$ ERA