000 AXNT20 KNHC 130515 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 115 AM EDT Wed Jun 13 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 along 20W from 04N-20N, moving west at 10-15 kt. This wave shows up as a low amplitude moisture surge on the TPW product. Currently, showers are limited near the wave's axis. African dust surrounds the wave limiting convection. A tropical wave is along 35W from 01N-11N, moving west at 10-15 kt. This wave shows up as a low amplitude moisture surge on the TPW product. Scattered moderate convection is from 03N-07N between 34W-38W. African dust is N of the wave axis limiting convection. A tropical wave is along 53W from 05N-15N, moving west at 10-15 kt. This wave shows up as a low amplitude moisture surge on the TPW product. Scattered moderate convection is within 120 nm either side of the wave axis. An upper-level trough is west of the tropical wave along 57W enhancing convective activity. A tropical wave over the E Caribbean extends from 18N65W to 06N65W, moving west at 10-15 kt. The wave coincides with a surge of moistened air, as noted in TPW imagery. Scattered showers are noted along the wave's axis south of 10N. A tropical wave over the W Caribbean extends from 20N82W to 11N82W, moving west at 10-15 kt. Scattered moderate convection is from 12N-20N between 78W-83W. An upper-level trough is west of the tropical wave along 87W enhancing convective activity. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 14N16W to 10N19W. The ITCZ extends from 07N22W to 04N34W, then resumes west of a tropical wave at 04N37W and continues to 04N51W. Besides the convection mentioned in the tropical wave section, scattered moderate convection is from 03N-07N between 38W-51W. Scattered moderate convection is also from 06N-10N between 56W- 60W. ...DISCUSSION... GULF OF MEXICO... A 1019 mb high is centered over the NE Gulf near 28N84W. 5-10 kt anticyclonic winds are noted around the high. 10-15 kt SE surface flow is over the remainder of the Gulf. Isolated moderate convection is noted over the Florida Peninsula, over the S Bay of Campeche, and over S Louisiana. An upper-level trough is over the Gulf with axis along 87W. An embedded upper level low is centered over the NW Gulf near 29N95W. A surface trough will develop along the Yucatan Peninsula late Wed and Thu afternoons, and drift westward across the southwest Gulf waters during the overnight hours accompanied by a strong east to southeast wind shift with the trough dissipating along 96W during the late mornings. The pressure gradient is tightening in association with a tropical wave moving through the Yucatan Channel on Wed. The wave will pass through the southwest gulf waters on Thu and Fri accompanied by a weak low pressure center along the wave axis. A fresh southeast breeze is expected across the central waters through Sat with locally strong conditions developing on Sat night into Sun. CARIBBEAN SEA... Two tropical waves are over the Caribbean. See above. Elsewhere, scattered moderate convection is inland from S Guatemala to Panama. An upper-level trough extends across the NW Caribbean with axis along 87W. Diffluent flow east of this trough is enhancing convection over the W Caribbean and central Cuba. A large upper- level ridge is over the remainder of the Caribbean with axis along 72W. A tropical wave will move west across the western Caribbean through Wed night with a surface low developing along the wave axis. A second tropical wave across the east Caribbean will pass through the central Caribbean on Thu and Fri. A third tropical wave will pass west through the tropical waters east of windwards on Wed, and pass through the east Caribbean on Thu and Fri. Strong trades currently across the south-central and southwest Caribbean will spread north across the central Caribbean on Wed and Thu, while fresh to locally strong southeast pulses will continue across the northwest Caribbean. Locally strong trades will continue across the tropical waters east of the Windwards through late Wed. ATLANTIC OCEAN... Abundant deep layer moisture continues to prevail in the western Atlantic and Bahamas, E of a deep upper-level trough with axis along 87W. Scattered moderate convection is observed west of 75W. A surface ridge dominates the remainder of the Atlantic, anchored by a 1029 mb high centered near 34N26W, producing fair weather. Moderate to locally fresh winds are noted along the southern periphery of the ridge from scatterometer data. The surface ridge will meander between 27N-29N through the week. A weak cold front is expected to pass east through the waters north of 26N on Sat. Fresh to locally strong easterly winds are forecast along the northern coast of Hispaniola during the late afternoons and evenings through Thu, with moderate easterly flow forecast elsewhere south of the ridge. Gentle to moderate southerly flow is expected north of the ridge, with a brief moderate northeast breeze expected to the north of the cold front on Sat. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa