000 AXNT20 KNHC 010605 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 AM EDT SAT OCT 1 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... Hurricane Matthew is centered near 13.3N 72.3W at 01/0300 UTC or about 70 nm NW of Punta Gallinas Colombia and about 382 nm SE of Kingston Jamaica moving W at 6 kt. Estimated minimum central pressure is 941 mb. Maximum sustained wind speed is 140 kt with gusts to 170 kt. Numerous strong convection is from 11N-15N between 69W-74W. Scattered moderate convection is elsewhere from 10N-17N between 67W-76W. See latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC and the full Forecast/Advisory under AWIPS/ WMO headers MIATCMAT4/WTNT24 KNHC for more details. ...TROPICAL WAVES... A tropical wave is in the central Atlantic extending from a 1011 mb low near 13N33W to 20N33W, moving W at 15-20 kt over the past 24 hours. The wave is in a region of favorable deep layer wind shear and in a region of middle level diffluence. However, the TPW and CIRA LPW imagery show dry air intrusion W of the wave axis. Meteosat enhanced imagery confirm the presence of Saharan dry air and dust in the wave environment, which is inhibiting convection at the time. A tropical wave is in the central Atlantic extending from a 1010 mb low near 14N50W to 22N52W, moving WNW at 10-15 kt over the past 24 hours. The wave is in a region of unfavorable deep layer wind shear and Saharan dry air and dust is observed mainly W of its axis. Low level moisture and middle level diffluence support scattered showers and isolated tstms from 11N to 22N between 42W and 52W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from 09N14W to a 1011 mb low near 13N33W to 07N35W. The ITCZ begins near 07N35W and continues to 06N45W. For information about convection see the tropical waves section above. ...DISCUSSION... GULF OF MEXICO... A broad deep layered low is centered over Indiana with troughing dipping southward over the eastern Gulf and a portion of the NW basin. The upper trough supports a stationary front extending across the northern Florida peninsula to 28N83W to 25N90W to 22N96W. The base of the upper trough extends S to Honduras and generates a diffluent environment over the far SE basin to support scattered showers and isolated tstms across the Florida Straits and the Yucatan Channel. Isolated showers are occurring across the SW Gulf generally S of the front W of 94W due in part to a diffluent environment aloft between the troughing and an upper level anticyclone centered S of the Baja California Peninsula. Clear skies prevail N of the frontal boundary as a surface ridge remains anchored across the central plains. The front is expected to gradually become diffuse through Sunday with light to gentle E-NE winds expected as ridging slides eastward to the N across the SE CONUS. CARIBBEAN SEA... The main concern in the basin is Hurricane Matthew located in the south-central Caribbean. See the speacial features section for details. An upper level ridge covers much of the Caribbean E of 80W while the base of an upper level trough extends from the Florida Straits to over Honduras. The upper level trough is supports isolated showers across the NW Caribbean with stronger convection occurring across inland portions of northern Belize and the southern Yucatan peninsula. Across the SW Caribbean...the Monsoon Trough axis extends along Costa Rica to northern Colombia and provides focus for scattered showers and tstms S of 14N. Otherwise, as Matthew tracks N-NW across the central Caribbean through Monday, the trades will continue to be disrupted. Trades will begin to re-establish from east to west starting Wednesday through early next weekend. ...HISPANIOLA... High level cloudiness associated with Hurricane Matthew in the south-central Caribbean continue to cover the Island. Isolated showers are likely occurring over the estern Dominican Republic and SW Haiti as well as the Windward Passage. Matthew is expected to track W through Saturday night before making a turn toward the NW then north late in the weekend. Heavy showers are expected across the Island from Sunday night through Wednedday when the cyclone will be moving across the northern Bahamas. ATLANTIC OCEAN... The deep layered trough over the eastern Gulf of Mexico extends over the far western portions of the SW North Atlc west of 76W supporting a stationary front extending from 31N81W to 28N82W then across the Gulf of Mexico waters to 22N96W. Scattered showers and isolated tstms prevails N of 22N W of 70W being supported by the trough aloft. The remainder of the Atlc is under the influence of a surface ridge anchored by a 1024 mb high near the Azores. The surface ridging is expected to persist through the weekend as Matthew moves through the Caribbean Sea. Then as Matthew begins its northward track...the ridge will shift east as Matthew moves into the SW North Atlc by early Tuesday. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS