000 AXNT20 KNHC 160540 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 140 AM EDT TUE AUG 16 2016 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 0530 UTC. ...SPECIAL FEATURES... A tropical wave is over the Eastern Atlantic just west of the Cabo Verde Islands with axis that extends from 15N26W to a 1008 mb low near 10N27W to 05N27W. Clusters of moderate isolated strong convection are noted within about 210 nm NW and SW quadrants of the low center. These features are in a moist environment and the wave has a noticeable 700 mb signature. Environmental conditions are expected to be conducive for development during the next few days, and a tropical depression is likely to form while the system moves west-northwestward to northwestward toward the central tropical Atlantic. Latest Tropical Weather Outlook gives this system a medium change of tropical development through the next 48 hours. ...TROPICAL WAVES... A tropical wave is over the central tropical Atlantic with axis from 20N48W to 08N49N moving west at 20 kt. The wave is in a moist environment as depicted by the SSMI Total Precipitable Water Imagery. However, dry air with Saharan dust is wrapping around the west side of the wave inhibiting significant convection at this time. The wave has a classic V-structure noticed on satellite imagery, with a swirl of low clouds along the wave axis. A tropical wave is over the Eastern Caribbean with axis that extends from the Mona Passage to the coast of Venezuela from 19N68W to 11N68W, moving west at 15-20 kt. The San Juan Doppler radar depicts isolated showers in association with this wave all around the island and the northeast Caribbean. A low amplitude bulge of moisture extends from the southern portion of the wave to about 16N as noted on the TPW imagery. This moisture is forecast to remain south of 20N as the wave continues west through the central Caribbean tonight and Tuesday. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the African coast near 16N17W to the Special Feature 1008 mb low pressure located near 10N27W to 08N38W. The ITCZ begins near 08N38W and continues to 07N57W. Aside from the convection associated with the tropical waves, scattered moderate convection is from 06N-09N between 48W-55W. ...DISCUSSION... GULF OF MEXICO... An elongated upper-level low extends across the central Gulf with axis along 90W. This feature is enhancing scattered moderate convection across the whole basin. To the south; scattered moderate to strong convection prevails across the northern portion of Central America and southern Mexico and is moving west approaching the Bay of Campeche mainly south of 21N. A thermal surface trough extends from 23N90W to 19N90W with scattered light to moderate convection along it. Scatterometer data depicts a gentle to moderate southeasterly flow across the basin. Expect during the next 24 hours for the upper-level low to dissipate. Convection will persist across the southwest Gulf. CARIBBEAN SEA... A tropical wave is over the Eastern Caribbean. Please refer to the Tropical Waves section above for details. Elsewhere, scattered moderate convection is over the NW Caribbean, south of Isle of Youth Cuba, from 18N-21N between 81W-84W supported by a diffluent flow aloft. Similar convection is over the SW Caribbean near the coast of Nicaragua due to the proximity of the Monsoon Trough. Scatterometer data and buoys observations indicate fresh to strong tradewinds over the central Caribbean with the strongest winds along the coast of Colombia. These winds are forecast to persist through mid-week, increasing to near gale force along the NW coast of Colombia during the overnight and early morning hours through Wednesday night. Moderate to fresh trades prevail elsewhere. ...HISPANIOLA... Fair weather prevails across the island at this time. A tropical wave is forecast to move across the island tonight and tomorrow and could enhance the convective activity during the afternoon and early evening hours. Computer model indicates that the convection associated with the tropical wave should remain south of the island over the next 24 hours. ATLANTIC OCEAN... Two tropical waves are moving westward between the coast of Africa and the Lesser Antilles. Please refer to the Tropical Waves section above for details. A diffluent flow aloft supports isolated moderate convection west of 75W. Surface ridge dominates the reminder of the area anchored by a 1026 mb high centered near 32N49W. The pressure gradient between the ridge and lower pressure over western Africa is producing near gale force winds from the northeast across the Canary Islands as noted in recent scatterometer data. The ridge will persist through the next 24 hours. For additional information please visit http://www.hurricanes.gov/marine $$ ERA