000 AXNT20 KNHC 060600 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 200 AM EDT TUE SEP 6 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 39.6N 70.7W at 06/0300 UTC, or about 104 nm SSE of the eastern tip of Long Island. Hermine is moving WNW at 8 knots. The estimated minimum central pressure is 995 mb. Maximum sustained winds are 55 knots with gusts to 65 knots. Scattered showers are within 330 nm NE and SW quadrants. Hermine is expected to become nearly stationary on Tuesday before turning toward the northeast on Wednesday. Hermine will produce total rain accumulations of 1 to 2 inches across eastern Massachusetts, including Cape Cod and the offshore islands, through Wednesday. Large waves generated by Hermine will affect the U.S. east coast from the mid-Atlantic states through New England. 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 10N to 20N with axis near 37W, moving W at 5-10 kt within the last 24 hours. The wave is in a region of favorable deep layer wind shear and Saharan dry air and dust is not evident in its immediate environment anymore. However, both CIRA LPW and the TPW show the wave axis is in a dry environment, which is hindering convection and any development at the time. A tropical wave is over the eastern Caribbean Sea extending from 10N to 20N with axis near 68W, moving W at 20 kt within the last 24 hours. A 1011 mb center of low pressure is associated with the wave, located near 14N67W and expected to move W to near 15N74W within 24 hours. Abundant moisture in the vicinity of the wave, favorable deep layer wind shear in the eastern Caribbean and a diffluent environment aloft support scattered heavy showers and isolated tstms from 14N to 18N between 62W and 71W and isolated showers to 21N and within 120 nm of low south semicircle. A tropical wave extends from the Bay of Campeche to southern Mexico into the NE Pacific waters. The wave extends from 10N to 21N with axis near 93W, moving W at 15 kt within the last 24 hours. The wave is in a favorable deep layer wind shear environment that along with abundant low level moisture support scattered to isolated showers across the Bay of Campeche. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 17N16W to 10N21W to 07N25W to 10N30W to 11N36W. Numerous heavy showers and tstms are off the Western coast of Africa from 10N to 18N E of 18W associated with a tropical wave. Scattered moderate to isolated strong convection is from 02N to 09N between 22W and 41W. Isolated showers are elsewhere from 06N to 15N between 37W and 47W associated with a 1012 mb low near 13N45W. ...DISCUSSION... ...THE GULF OF MEXICO... Weak surface ridging prevails across the Gulf waters, except for the far SW portion of the basin where a tropical wave along 93W is supporting scattered to isolated showers in the Bay of Campeche. Surface observations and scatterometer data indicate moderate E to SE winds basin-wide, except for locally fresh E-NE winds in the vicinity of the tropical wave axis. Cloudiness and scattered showers and thunderstorms over the SE basin being supported by middle to upper level diffluence. The tropical wave moving across the Bay of Campeche over the next few days will support enhanced winds and showers there. Elsewhere surface ridging will remain as the main feature the next two days. ...THE CARIBBEAN SEA... The main concern for the basin is a tropical wave that is moving across the eastern Caribbean. Abundant moisture in the vicinity of the wave, favorable deep layer wind shear in the eastern Caribbean and a diffluent environment aloft support scattered heavy showers and isolated tstms from 14N to 18N between 62W and 71W and isolated showers to 21N and within 120 nm of low south semicircle. Locally strong winds to near gale force is possible in some of the heavier squalls passing over and to the south of Dominican Republic and Puerto Rico. This disturbance could produce periods of locally heavy rainfall and gusty winds over portions of the Lesser Antilles, Puerto Rico and Hispaniola tonight and on Tuesday. Development of the wave is unlikely while it moves westward across the Caribbean Sea for the next few days. Upper-level winds could become a little more conducive for development when the wave approaches the Yucatan peninsula late this week. Please refer to the tropical waves section for details. The monsoon trough supports scattered heavy showers in the SW basin within 150 nm off the coasts from Honduras to Colombia. Fresh to locally strong winds are noted elsewhere in the Caribbean from 12N to 19N between 66W and 82W and across the Windward Passage. ...HISPANIOLA... Increasing multilayered cloudiness is spreading across the Dominican Republic in advance of the strong tropical wave along 68W. The potential for very heavy rainfall exists on Tue into Wed across the island as the strong tropical wave continues westward in the Caribbean. Drier weather is expected by Thursday as the wave moves away from the island. ...THE ATLANTIC OCEAN... Post-tropical cyclone Hermine is N of forecast waters. Please refer to the special features section for details. A surface trough, remnants of a frontal boundary, prevails across SW N Atlantic waters extending from 30N70W to 27N74W to 25N80W. Isolated showers and tstms are within 60 nm either side of the trough axis. Farther east, a second surface trough extends from 29N51W to 24N54W, however no convection is associated with it a the time. A third surface trough extends from 30N32W to 23N38W with scattered showers within 60 nm either side of its axis N of 28N. Isolated showers are within 120 nm N of the Dominican Republic and Puerto Rico coasts associated with a tropical wave in the Caribbean with axis near 68W. Lastly, a 1012 mb low in the deep tropics near 13N45W supports scattered showers from 07N to 15N between 40W and 47W. The remainder of the basin is dominated by a broad but weak surface ridge. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS