000 AXNT20 KNHC 151742 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 142 PM EDT Mon May 15 2017 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 1200 UTC surface analysis and satellite imagery through 1600 UTC. ...TROPICAL WAVES... A tropical wave is over the eastern tropical Atlantic with an axis extending from 10N24W to 01N25W, moving westward at about 15 kt. This wave continues to appear in satellite imagery and in model diagnostics. Isolated moderate convection is within 240 nm of either side of the wave axis S of 05N. A tropical wave is over the central Atlantic with an axis extending from 10N46W to 00N45W, moving westward at around 20 kt. This wave continues to be difficult to locate in satellite imagery, with a just subtle poleward push of low to mid level moisture with the wave passage. No convection is currently occurring with this wave. A tropical wave is over eastern Venezuela with an axis extending along 64W, south of 11N, moving westward at 15 to 20 kt. This wave coincides with a surge of deep moisture. However, due to subsidence over the eastern Caribbean, no convection is currently occurring with this wave over the Caribbean waters. A tropical wave extends from the southwest Caribbean near 12N74W to Colombia, moving westward at 10 to 15 kt. This wave shows up well in 850 mb model streamlines. Scattered thunderstorms are within 120 nm of the wave axis, S of 12N. ...ITCZ/MONSOON TROUGH... The monsoon trough crosses the western African coast near 08N13W to 04N20W. The ITCZ begins near 04N27W and extends to 06N43W, then resumes east of a tropical wave near 06N48W to 05N54W. Aside from the convection related to the tropical waves, isolated moderate convection is within 120 nm of the monsoon trough axis. ...DISCUSSION... GULF OF MEXICO... A dissipating stationary front extends from 25N81W to 23N87W. Isolated showers and thunderstorms are within 90 nm of either side of the front. A weak surface trough is over the eastern Gulf with an axis from 30N84W to 26N83W. No convection is noted with this trough. High pressure centered over Alabama extends across the remainder of the Gulf supporting mainly moderate easterly winds. Over the next 24 hours expect isolated showers and thunderstorms to continue over the southeastern Gulf. CARIBBEAN SEA... A surface trough extends from 21N81W to 16N83W to 12N83W. This trough is interacting with an upper trough to the northwest, along with deep moisture in the vicinity of the surface trough, to support scattered moderate convection with thunderstorms from 12N to 22N between 77W and 83W. The eastern Pacific monsoon trough currently extends across Costa Rica and Panama, supporting scattered thunderstorms south of 11N over the southwestern Caribbean. A pair of tropical waves are crossing the northern portion of south America. Please refer to the tropical waves section for more details. Mainly moderate trades cover the Caribbean east of the surface trough, with mainly gentle winds to the west of the surface trough. Over the next 24 hours the surface trough will drift north to northeast with numerous showers and scattered thunderstorms. HISPANIOLA... The combination of an upper trough over the southeast Gulf of Mexico and a surface trough over the western Caribbean is supporting increasing moisture from west to east over the area today. Expect scattered showers and thunderstorms in daytime heating today. Moisture will continue to increase tonight and Tuesday as the surface trough drifts toward the island. This will result in increasing chances for showers and thunderstorms the next few days. ATLANTIC OCEAN... Two tropical waves are moving across the tropical Atlantic. Please refer to the tropical waves section above for details. A cold front is over the southwest N Atlantic and extends over the area of discussion from 31N67W to 27N75W, then transitions to a stationary front to the Florida Straits. Scattered showers and thunderstorms are within 300 nm southeast of the front. A surface trough is north of the front extending from 30N71W to 29N81W. No convection is noted with this trough. A 1022 mb high is centered near 27N49W, providing much of the central Atlantic with fair weather. A dissipating cold front extends from 31N32W to 27N38W to 25N46W. Isolated thunderstorms are within 120 nm SE of the front. Over the next 24 hours high pressure will build across the southeastern United States and the western Atlantic. Showers and thunderstorms will continue and increase over the central and southeast Bahamas. For additional information please visit http://www.hurricanes.gov/marine $$ Latto