000 AXNT20 KNHC 160000 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 800 PM EDT Thu Mar 15 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Sierra Leone on the coast of Africa near 07N12W to 05N16W. The ITCZ continues from 05N16W to 03N27W to 02N40W to the coast of Brazil near 01S52W. Scattered moderate and isolated strong convection is present from 01N to 05N between 20W and 29W. ...DISCUSSION... GULF OF MEXICO... High pressure is centered over the NE Gulf near the Florida Big Bend. The high is generally maintaining light to moderate E to SE winds over the NE half of the Gulf. Moderate to fresh SE winds have already developed over the SE half of the Gulf. The high will drift slowly SE from the NE Gulf over the SW N Atlantic waters near the Bahamas and Straits of Florida by early Saturday morning, then linger in this vicinity through Monday. Return flow on the western half of the basin will remain moderate to fresh on late tonight ahead of an area of low pressure developing in the central plains. This low will head ESE into the Atlantic near Cape Hatteras on Sat and Sat night. Stronger low pressure moving E through the southern plains will drag a cold front into the western Gulf on Mon night. CARIBBEAN SEA... The frontal boundary over the NW Caribbean has dissipated. NE to E winds over the basin are primarily moderate to fresh, except for fresh to strong winds along the coast of Colombia. Remnant moisture left behind continues to support isolated showers over the Windward Passage and western Caribbean. This weather regime will remain in place through early next week as the high pressure to the north remains weakened by low pres systems moving eastward from the United States mainland. Relatively dry conditions prevail and will continue through this weekend as mid to upper- level ridging from the east resides over the basin. ATLANTIC OCEAN... Deep layer low pressure centered between Newfoundland and Labrador supports a cold front that extends SW from 32N55W to 26N63W to the western Dominican Republic near 20N71W. A second cold front extends from 32N60W to 27N68W. Scattered showers and isolated thunderstorms are occurring along and up to 60 nm ahead of the front N of 22N. Cloudiness and patchy rain are found along and up to 90 nm NW of the front N of 22N. Fresh to strong southerly winds are observed along and up to within 300 nm E of the front N of 28N. The reinforcing front will merge with the primary front this evening. The combined front will then dissipate into a trough during the weekend. High pressure will shift E from the NE Gulf of Mexico behind the front later today and Fri, then continue east into the west Atlantic along 27N this weekend. A broad area of high pressure prevails across the central and eastern Atlantic, anchored by a 1025 mb high centered near 28N41W. The high is maintaining moderate to fresh northeast winds over the tropical Atlantic north of the ITCZ between 30W and the Windward Islands. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy