000 AXNT20 KNHC 050603 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 203 AM EDT MON SEP 5 2016 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 0545 UTC. ...SPECIAL FEATURES... Post-tropical cyclone Hermine is centered near 37.2N 68.5W, about 282 nm SE of the eastern tip of Long Island. Hermine continues to move slow NNE at 3 knots. The estimated minimum central pressure is 997 mb. Maximum sustained winds are 60 knots with gusts to 75 knots. Scattered moderate convection and isolated tstms are mainly to the N of Hermine center from 38N to 42N between 56W and 74W. Hermine should remain near hurricane strength through Monday. Gradual weakening is forecast to begin by Monday night. Large waves generated by Hermine will affect the U.S. east coast from the mid-Atlantic states and expand northward along the coast of southern New England through Monday night. These waves are likely to cause life-threatening surf and rip current conditions, and significant beach erosion. Please read the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC and the Forecast/Advisory under the AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more details. ...TROPICAL WAVES... A tropical wave is over the central Atlc extending from 08N to 21N with axis near 35W, moving west at 10 kt within the last 24 hours. A 1013 mb low is associated with the wave and is located near 20N36W, which is expected to move NW to 23N39W within the next 24 hours. The wave is in a region of favorable deep layer wind shear from 10N to 20N, however continuous intrusion of Saharan dry air and dust in the wave environment is limiting convection to scattered moderate in the NE quadrant of the low from 22N to 27N between 32W and 37W. Isolated showers are elsewhere within 370 nm E of the wave axis. A tropical wave is entering the Caribbean Sea. The wave extends from 10N to 19N with axis near 60W, moving W at 15 kt within the last 24 hours. A 1010 mb center of low pressure is associated with the wave, which is located near 15N60W, which is expected to dissipate within the next 24 hours. Abundant moisture in the vicinity of the wave along with a diffluent environment aloft support a cluster of heavy showers and isolated tstms from 14N to 17N between 59W and 62W. A gale warning is in effect for the Leeward Islands and adjacent waters through sunrise Monday. A tropical wave is over the far western Caribbean extending from 08N to 20N with axis near 88W, moving at 20 kt within the last 24 hours. The wave is in a favorable deep layer wind shear environment that along with diffluent flow aloft support isolated showers from 19N to 23N between 83W and 88W, including the Yucatan Channel. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 16N16W to 10N35W to 11N49W. The ITCZ begins near 11N50W and continues to 14N59W. Scattered moderate convection is from 04N to 09N between 18W and 27W and from 05N to 12N between 32W and 48W. ...DISCUSSION... ...THE GULF OF MEXICO... Weak surface ridging prevails across the Gulf waters, except for the SW basin where low level moisture convergence associated with a surface trough extending from 22N90W to 18N93W support heavy showers and tstms in the Bay of Campeche W of 92W. The ridge provides gentle to moderate E to SE winds basin-wide except across the eastern Bay of Campeche where moderate to fresh NE flow is supported by the surface trough. Cloudiness and isolated showers are in the N-NE Gulf coast and adjacent waters associated with the remnants of a former surface trough. A tropical wave moving across the far W Caribbean support scattered showers in the Yucatan Channel. Surface ridging will remain as the main feature the next two days. ...THE CARIBBEAN SEA... The main concern for the basin is a vigorous tropical wave that is moving across the central and northern Lesser Antilles. This wave is supporting heavy showers and isolated tstms from 14N to 17N between 59W and 62W. A gale warning is in effect for the Leeward Islands and adjacent waters through Monday sunrise. This disturbance will continue to produce locally heavy rainfall and gusty winds over portions of the Lesser Antilles today, and should spread over Puerto Rico and Hispaniola during the next day or two. Another tropical wave is moving across the far western Caribbean supporting scattered showers from 19N to 23N between 83W and 88W, including the Yucatan Channel. Please refer to the tropical waves section for details. The monsoon trough support scattered to isolated showers in the SW basin within 150 nm off the coasts from Nicaragua to Colombia. Fair weather is elsewhere. Fresh to strong winds are in the Caribbean from 11N to 13N between 70W and 77W. ...HISPANIOLA... Fair weather prevails across the island due to strong subsidence aloft as indicated by water vapor imagery. Stable and fair weather is expected to continue tonight. On Monday and Tuesday, a moist air mass associated with an approaching tropical wave will support showers. Drier weather is expected by Thursday as the wave moves away westward. ...THE ATLANTIC OCEAN... Post-tropical cyclone Hermine is N of forecast waters. Please refer to the special features section for details. Two tropical waves are moving across the basin. Please refer to the tropical waves section for details. A divergent environment aloft across central Florida and adjacent waters support scattered showers and isolated tstms from 27N to 29N extending within 120 nm off the coast. A surface trough prevails in the SW N Atlc waters from 30N72W to 28N78W supporting isolated showers within 60 nm either side of its axis. Another surface trough is on the northern central Atlc from 30N47W to 27N52W with isolated showers within 30 nm either side of its axis. The remainder of the basin is dominated by a weak and broad surface ridge. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS