000 AXNT20 KNHC 150004 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 804 PM EDT Mon May 14 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. ...SPECIAL FEATURE... An upper-level low is centered over the NE Gulf of Mexico near 26N85W. Divergent upper-level winds on the E side of the low have induced the formation of a broad area of weak surface low pres over the eastern Gulf. Specifically, a surface trough extends SW from N of Tampa near 29N83W to low pres 1012 mb near 27N84W to low pres 1012 mb near 25N85W to 22N86W. A large area of scattered moderate and isolated strong convection is currently present over Florida, Cuba and the Bahamas within an area bounded by 31N84W to 20N85W to 24N75W to 31N80W to 31N84W. Although this system could still acquire some subtropical or tropical characteristics while it crawls N across the eastern Gulf of Mexico during the next few days, the low has not shown signs of increased organization during the past 24 hours. Regardless of subtropical or tropical cyclone formation, this system will produce locally heavy rainfall and possible flash flooding across portions of Florida and the southeastern United States during the next few days. ...MONSOON TROUGH/ITCZ... The monsoon trough heads SW from coastal sections of Sierra Leone near 08N13W to 05N17W. The ITCZ continues from 05N17W to 02N30W to 02N39W to the Mouth of the Amazon on the coast of Brazil near 00N51W. Scattered moderate convection is observed from 02N to 05N between 11W and 18W and from 02N to 05N between 43W and 51W. ...DISCUSSION GULF OF MEXICO... A broad low pressure system will linger over the eastern Gulf and produce heavy rainfall and will be the main weather producer over the eastern Gulf the next few days. Moderate to fresh winds are present on the NW side of the low. Please see the special features section for more details on this system. High pressure over the southern United States ridges SW over the W half of the Gulf and is inhibiting convection there. The trough is expected to form over the Yucatan Peninsula this evening and move offshore tonight over the Bay of Campeche bringing with it a return of fresh winds. This pattern will continue to repeat itself through this week. Otherwise, little change is expected over the western Gulf over the next few days. CARIBBEAN SEA... Convergent upper-level winds associated with troughing over the basin near 80W and over the Antilles is restricting convection. This relatively dry weather pattern is expected to continue for the next couple of days. High pressure over the Atlantic is helping to produce moderate trade winds over the northern Caribbean, and mainly fresh trade winds over the southern Caribbean. Winds over the southern Caribbean near the coast of Colombia will pulse to strong at night the next few nights, expanding to include the south central coast of Hispaniola by midweek. ATLANTIC OCEAN... Deep layer low pressure centered over the eastern Gulf of Mexico is supporting scattered moderate and isolated strong convection over the central and NW Bahamas and the Florida offshore waters generally W of 75W. See the special feature section for more details. A broad area of high pressure centered near the Azores ridges WSW to near 32N77W. The pressure gradient between the high pressure and lower pressure associated with the Gulf of Mexico trough/low supports fresh SE winds over the central and NW Bahamas and nearby waters. Gentle to moderate winds cover the Atlantic between 27N and 31N. Moderate to fresh trade winds cover the Atlantic S of 27N. The high pressure ridge will maintain these winds through Thu, except with winds increasing over the Bahamas and E of north Florida to fresh to strong tonight. Also, winds N of Hispaniola will pulse from fresh to strong from afternoon to late evening each day through Sat. The area of strong winds N of Hispaniola will expand northward to as far as 23N by Sat as the high pressure ridge over the western Atlantic gradually strengthens and low pressure over northern South America deepens slightly. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy