000 AXNT20 KNHC 110540 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 140 AM EDT Sun Jun 11 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 0000 UTC surface analysis and satellite imagery through 0530 UTC. ...TROPICAL WAVES... A tropical wave extends its axis from 14N22W to 06N22W, moving westward at 15 to 20 kt. This wave is embedded in a deep moisture surge and an inverted trough is noted at 700 mb. An area of numerous moderate convection prevails south of 10N between 16W- 28W. A central Atlantic tropical wave extends its axis from 15N35W to 06N35W, moving westward at about 10-15 kt. The wave shows up pretty well in the TPW animation and 700 mb streamline analysis. Convection is limited near the wave's axis. A tropical wave is located near the Lesser Antilles. This wave's position is been reviewed to be repositioned based on sounding data and model diagnostics. The presence of an upper-level low centered north of Puerto Rico is making it difficult to differentiate between the presence of the tropical wave or the upper-level feature. A weak tropical wave extends its axis from 15N79W to 06N80W. An area of showers is observed west of the wave's axis between 81W- 83W. ...MONSOON TROUGH/ITCZ... The Monsoon Trough enters the Atlantic Ocean from 14N17W to 08N21W then resumes west of a tropical wave near 08N24W to 09N34W. The ITCZ extends from 09N37W to 10N61W. Aside from convection discussed in the tropical waves section, a small cluster of moderate convection is from 07N-11N between 46W-51W. ...DISCUSSION... GULF OF MEXICO... The surface trough extends across the western Gulf from 26N91W to 20N92W. To the south, scattered moderate convection prevails along the Yucatan Peninsula. To the east, a diffluent flow aloft is supporting scattered moderate convection east of 90W, with strongest activity north of 25N. The trough will continue to drift northwest through Sunday accompanied by showers and thunderstorms. Computer models indicate abundant moisture across the Gulf region east of 92W, including the Yucatan Peninsula and most of the Florida Peninsula on Sunday, resulting in more shower and thunderstorm activity. Moderate to locally fresh southerly winds are south of the trough's axis. Mainly moderate E to SE winds cover the remainder of the Gulf. High pres will build west across Gulf in the wake of the trough Sunday through late Monday with increasing winds and seas. CARIBBEAN SEA... Please refer to the section above for more information about tropical waves. The proximity of the Monsoon Trough currently extending over Central America is supporting scattered moderate convection across this area. Scatterometer data provide observations of moderate to fresh southerly winds across the northwest Caribbean due to the pressure gradient between the Atlantic ridge and the trough over the Gulf of Mexico. Fresh to strong trades are over the south-central Caribbean, with the strongest winds within 90 nm to the north of the coast of Colombia. The Atlantic high pressure centered near 31N54W will maintain fresh to strong trades across the basin Sunday and Monday, with the strongest winds across the south-central Caribbean. ...HISPANIOLA... A few showers and thunderstorms were noted over the island in the evening hours due to local effects. Dry air and subsidence aloft will continue over the island through tonight. Little change is expected through 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 frontal trough extends from 31N74W to northeast Florida near 29N81W, supporting scattered showers and thunderstorms in this area. This convective activity is affecting mainly the central and north portions of Florida and the western Atlantic waters north of 29N and west of 71W. This trough will continue to drift northwest and weaken through Sunday. To the east, a cold front is moving southward across the central Atlantic and extends from a weak 1018 mb low pressure near 28N45W to 24N48W to 24N56W. Latest satellite imagery showed very well the developing low pressure and the frontal boundary. The cold front will continue to move southward across the central Atlantic on Sunday, then stall and drift back on Monday. The remainder of the Atlantic is under the influence of a surface ridge, anchored by a 1026 mb high pressure located near 31N55W. The high pressure will move slowly westward over the next 24 hours. For additional information please visit http://www.hurricanes.gov/marine $$ ERA