000 AXNT20 KNHC 271031 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Jul 27 2021 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 0930 UTC. ...TROPICAL WAVES... A tropical wave is in the E Atlantic south of 20N with axis along 31W/32W, moving W at 10-15 kt. A broad area of Saharan Air accompanies this wave, which is hindering convection north of 10N at this time. Associated scattered moderate convection is confined to near the ITCZ, from 05N to 09N between 28W and 38W. A tropical wave is in the E Caribbean extending S of 15N along 69W, moving W at 15 kt. A dry and stable low-level dry airmass immediately follows this wave and is limiting convection to isolated showers to S of 13W and E of 69W. A tropical wave is in the central Caribbean extending S of 20N with axis near 79W, moving W at 10-15 kt. Upper-level divergence is supporting scattered showers and isolated tstms from Jamaica to coastal Nicaragua. An ill defined tropical wave is in the W Caribbean extending from the Gulf of Honduras south into the eastern Pacific waters along 87W. Scattered moderate to strong convection is across coastal Nicaragua, and across the Pacific waters N of 11N between 88W and 91W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 12N16W to 07.5N31W to 08N41W. The ITCZ continues from 08N41W to 09.5N60W. Scattered moderate isolated strong convection is from 05N to 12N east of 53W. GULF OF MEXICO... A weak pressure gradient across the basin supports light to gentle variable winds across the gulf with seas in the 1 to 3 ft range. A middle to upper-level low over the western basin supports scattered to isolated showers over the NE Mexico adjacent waters. Over the eastern half of the basin, a surface trough supports similar shower activity on the SE gulf and Yucatan Peninsula. Weak high pressure persists across the northern Gulf along 29N while a trough extends from offshore of Tampa Bay, Florida to 24N91W. Scattered showers and isolated thunderstorms will persist near and south of the trough axis through tonight as if drifts westward. Atlantic high pressure will begin to build westward into the Gulf region Wed and Thu, with a ridge persisting along 27N through Sat. CARIBBEAN SEA... Three tropical waves are moving across the Caribbean supporting some localized shower activity. Aside from showers, two of these waves are supporting moderate to locally fresh trade winds across the eastern and central Caribbean with seas to 5 ft. See the tropical waves section for further details. Gentle to moderate trade winds are expected through early Wed. The exception will be moderate to locally fresh winds near the coast of Colombia, and in the Gulf of Venezuela. Winds will increase across the E and central Caribbean Wed night through Fri as the Atlantic ridge builds westward in the wake of a trough moving westward across the Atlc waters north of the Greater Antilles. ATLANTIC OCEAN... A surface ridge dominates the subtropical Atlantic waters and supports and provides mostly fair weather with gentle to moderate winds, and seas in the 3 to 5 ft range. A surface trough is analyzed near 24N57W to 17N56W. A small cluster of scattered showers and thunderstorms are noted in the vicinity of the trough. Otherwise, diffluent flow aloft supports scattered showers NE of the Bahamas. A weak Atlantic ridge extends from SE of Bermuda to near the NW Bahamas and will change little through tonight. An elongated area of showers and thunderstorms extending northward of 21N between 62W and 70W will persist north today then begin to diminish tonight. A broad inverted trough along 57W will move quickly westward and across the SE waters through tonight then north of the Greater Antilles and across the southern Bahamas Wed through Thu. $$ Stripling