000 AXNT20 KNHC 102340 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 740 PM EDT Sat Jun 10 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...TROPICAL WAVES... A tropical wave that exited the coast of Africa yesterday extends from 13N20W to 04N20W, moving westward at 15 to 20 kt. This wave is embedded in a deep moisture surge and inverted 700 mb trough. An area of numerous moderate and isolated strong convection is noted from 03N to 10N between 15W and 25W. A central Atlantic tropical wave extends from 15N34W to 05N35W, moving westward at about 20 kt. The wave shows up pretty well in the TPW animation and 700 mb streamline analysis. Convection is limited near the wave axis. A tropical wave is moving across the Lesser Antilles. Its axis extends from Guadeloupe to the NE coast of Venezuela where is helping to induce some convective activity. The wave has produced a few showers across the islands. Moisture associated with the wave will reach the central Caribbean by late Sunday. Another tropical wave is moving across the SW Caribbean and extends from 16N79W across eastern Panama into the EPAC region. An area of showers with embedded thunderstorms is south of 11N between 77W and 81W. This convective activity is affecting parts of Panama. ...MONSOON TROUGH/ITCZ... The Monsoon Trough enters the Atlantic Ocean through Sierra Leone and continues to 08N20W to 09N34W. The ITCZ extends from 09N37W to 08N50W to 09N60W. A pair of tropical waves are within the Monsoon Trough/ITCZ. In addition, a surface trough is analyzed along 47W from 06N to 13N. Aside from convection discussed in the tropical waves section, a small cluster of moderate convection is where the trough meets the ITCZ. ...DISCUSSION... GULF OF MEXICO... The surface trough, previously located over the SE Gulf and the NW Caribbean, continues to drift NW and currently extends across the Gulf of Mexico from near Tampa Bay to 25N90W to the central Bay of Campeche. Upper diffluence between an upper-level trough located over the western Gulf and anticyclone situated over the NW Caribbean is helping to induce convection near the trough axis and surrounding areas. Satellite imagery and lightning data show scattered to numerous showers and thunderstorms across the eastern Gulf, the Yucatan Peninsula and the Florida Peninsula, more concentrated over central Florida. The trough will continue to drift NW through Sunday accompanied by showers and tstms. Computer model indicates abundant moisture across the Gulf region east of 92W, including the Yutacan 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 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 increasing winds and seas. CARIBBEAN SEA... A tropical wave is moving across the Lesser Antilles. Another tropical wave is interacting with the eastern Pacific Monsoon Trough to support convection over portions of the SW Caribbean and Panama. Please refer to the Tropical Waves section for more details. Showers and thunderstorms are also noted over portions of Central America, particularly along the Pacific side due to a northward displacement of the Monsoon Trough. Locally heavy rains should spread over the coasts of El Salvador, Guatemala, and southeastern Mexico during the next few days. See the Eastern Pacific Tropical Weather Discussion for more details. Scatterometer data provide observations of moderate to fresh southerly winds across the NW Caribbean due to the presion 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 near the coast of Colombia. The Atlantic high pressure centered near 29N58W will maintain fresh to strong trades across the basin Sunday and Monday, with the strongest winds across the south- central Caribbean, the SW Caribbean and Gulf of Honduras. ...HISPANIOLA... A few showers and thunderstorms were noted over the island late in the afternoon and evening hours due to local effects. Dry air and subsidence aloft will continue over the island through tonight. A mid to upper level low to east of the area will cross the island on Sunday, with the more unstable portion of the low reaching Hispaniola Sunday afternoon. This will cause an increase in showers and thunderstorms Sunday afternoon and evening. 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 NE Florida near 29N81W, supporting scattered to numerous showers and thunderstorms. This convective activity is affecting mainly the central and north portions of Florida and the Atlantic waters north of 27N and west of 72W. This trough will continue to drift N-NW and weaken through Sunday. A cold front is moving southward across the central Atlantic and extends from a weak 1018 mb low pressure near 28N44W to 24N50W to 26N55W. Visible satellite imagery showed very well the developing low pressure along 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 ridge, anchored by a 1025 mb high pressure located near 29N58W. The high pressure will move slowly nortward over the next 24 hours. For additional information please visit http://www.hurricanes.gov/marine $$ GR