000 AXNT20 KNHC 131805 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 PM EDT Mon Mar 13 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 1200 UTC surface analysis and satellite imagery through 1745 UTC. ...SPECIAL FEATURES... A center of low pressure is forecast to develop across the offshore waters of the Carolinas tonight further increasing the pressure gradient along the SE CONUS coast. Current fresh to strong E-SE winds to the E of an elongated surface trough will increase to gale force tonight N of 29N between 66W and 79W. The gale warning will persist through Tuesday morning across the SW North Atlc waters in association with a cold front. See latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/ FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough axis extends from the African coast near 06N10W to 02N20W. The Intertropical Convergence Zone axis extends from 02N20W to 01N30W to the coast of Brazil near 02S44W. Scattered moderate to isolated strong convection is from 01N-07N between 10W and 18W and from 02S-04N between 28W and 34W. ...DISCUSSION... GULF OF MEXICO... A middle to upper level trough over the central United States extends S-SW across the western Gulf to northern Mexico, thus supporting a 1013 mb low centered near 27N91W from which a cold front extends SW to 21N94W. Moderate to fresh southeasterly to southerly flow dominating the eastern Gulf waters leads to a warm front extending from the low to 29N87W to Naples Florida. In the southern Gulf, a surface trough extends from 24N87W to the eastern Bay of Campeche near 19N91W. Middle to level moisture and diffluent flow aloft support heavy showers and isolated tstms N of 24N E of 92W while the experimental GOES lighting density product show an area of strong convection and severe tstms N of 27N between 88W and 90W. Fresh to strong winds are in the NE quadrant and SE semicircle of the low within a distance of 90 nm. The experimental GOES IFR product show moderate to high chances of dense fog along the coast of the NW Gulf, which is being confirmed by surface observations. The low is forecast to move toward central Florida tonight and then merge with the Special Features low pressure area to develop off the coast of the Carolinas...with the associated cold front sweeping east of the basin by Tuesday. High pressure will build in Tuesday behind the front providing moderate to fresh northerly winds. CARIBBEAN SEA... The basin continues to be under the influence of relatively dry and stable conditions aloft due to an upper level ridge. At the surface, overall conditions remain fair. The exception continue to be Hispaniola and adjacent waters, Jamaica and adjacent waters in the lee of eastern Cuba. Moderate to fresh trades are expected to continue through Tuesday night. A weakening cold front is expected to bring moderate to fresh northerlies to the NW Caribbean by Tuesday night into Wednesday. ...HISPANIOLA... Isolated shower activity continues across the region including southern adjacent waters. Conditions are expected to improve Tuesday morning as the patch of moisture moves to the Windward Passage and eastern Cuba. ATLANTIC OCEAN... An elongated surface trough formed this morning along Georgia and the Carolina's adjacent waters extending S to inland eastern Florida peninsula. Scattered showers and isolated tstms in the vicinity of this trough are being supported mainly by a broad area of middle level diffluence. Farther east, the remnants of a stationary front are analyzed as a surface trough from 31N67W to 31N72W to 28N78W. High pressure to the N tightens the gradient in the vicinity of these two features, thus supporting fresh to strong E-SE winds between them. The trough along Florida will become the area of low pressure described in the Special Features, leading to the development of gale force winds. See that section for further details. This low will be associated with a cold front that will move eastward to 60W by Friday with a trailing stationary front lingering SW toward the Windward Passage region. High pressure will build in W of the front providing strong to near gale N-NW winds Tuesday night through Wednesday night. Farther east, a stationary front extends from 31N50W SW to 26N65W. Widely scattered showers and isolated tstms are occurring within 60 nm either side of the front. Finally...the remainder of the eastern Atlc is under the influence of a surface ridge anchored by a 1040 mb high centered NE of the Azores. No significant convection is occurring...however near gale force E-NE winds were noted on ASCAT data from 26N-34N E of 30W. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos