000 AXNT20 KNHC 051745 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 145 PM EDT Thu Oct 5 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 1715 UTC. ...SPECIAL FEATURES... Tropical Storm Nate is centered near 14.5N 84.0W at 05/1800 UTC or about 45 nm NW of Puerto Cabezas Nicaragua and about 45 nm SSW of Puerto Lempira Honduras moving NW at 8 kt. Estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Scattered to numerous moderate and scattered strong convection is from 11N-19N between 78W-86W. See the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT1/WTNT31 KNHC and the full Advisory/Forecast under AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC for more details. ...TROPICAL WAVES... A tropical wave extends from 08N33W to 13N30W moving W at 10-15 kt. The wave has remained low-amplitude since emerging off the African coast several days ago. A recent ASCAT pass around 05/1118 UTC indicated fresh to strong low-level cyclonic winds focused around the wave axis with strong to near gale force southerly winds noted S of the ITCZ axis analyzed along 08N in the vicinity of the wave axis. Scattered moderate convection is from 05N-12N between 26W-38W. A tropical wave extends from 09N47W to 17N41W moving W at 10-15 kt. The wave coincides with troughing at 700 mb between 40W-48W with a recent ASCAT pass around 05/1112 UTC indicating a defined wave axis. Isolated moderate convection is from 15N-18N between 36W-41W. Scattered moderate convection is from 09N-15N between 44W-53W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 11N15W to 10N19W. The Intertropical Convergence Zone axis extends from 10N19W to 09N30W to 07N40W to 08N44W. Besides the convection associated with the tropical waves...no significant deep convection is occurring at this time. ...DISCUSSION... GULF OF MEXICO... North-northeasterly flow aloft persists over the Gulf basin this afternoon between an upper level anticyclonic circulation centered over northern Mexico and Texas...and an upper level low centered over the Yucatan peninsula with a sharp trough axis extending N-NE to over the Florida Big Bend region near 29N83W. The troughing supports a 1007 mb low centered across the Florida Straits near 24N82W with a surface trough extending to the south across western Cuba and to the N-NE to near Lake Okeechobee to east of Jacksonville Florida in the SW North Atlc. Isolated showers and tstms are occurring S of 28N E of 86W...including much of the Florida peninsula where upper level divergence is maximized. The remainder of the basin is under the influence of relatively drier NE flow aloft and fresh to strong easterly winds on the southern periphery of surface ridging anchored across the SE CONUS and eastern Texas. The low and associated troughing is expected to move westward into central Gulf waters by Friday with convective precipitation impacting much of the Florida peninsula and eastern two-thirds of the Gulf through Friday night into Saturday. By early Saturday...Tropical Storm Nate is forecast to have emerged into the south-central Gulf waters. CARIBBEAN SEA... Primary focus remains across the western Caribbean and Central America as Tropical Storm Nate tracks NW. In addition...broad surface troughing embedded within lower pressure across the western Caribbean extends southward from a 1007 mb low centered across the Florida Straits. The surface trough extends from 23N82W to 21N82W to 18N84W. Outside of the influence of Tropical Storm Nate...scattered to numerous showers and scattered strong tstms are occurring from 10N-20N between 72W-85W...with widely scattered showers and tstms occurring elsewhere from 08N-22N between 72W- 91W...including Cuba...and a large portion of Central America. Otherwise...farther east...a surface trough extends from the NW corner of Puerto Rico near 18N67W N-NE to across the Atlc waters providing focus for scattered showers and isolated tstms across the eastern Caribbean waters N of 13N between 64W-68W. This activity is supported aloft by an upper level low centered near 13N64W and associated upper level troughing extending to the N-NW to over Puerto Rico. Finally...outside of the influence of Tropical Storm Nate...moderate to occasional fresh trades prevail E of 72W. ...HISPANIOLA... Currently skies remain mostly fair across interior portions with cloudiness increasing throughout the daytime hours and isolated to scattered showers possible through the evening. Surface troughing to the east approaching the Mona Passage region and an upper level trough currently over Puerto Rico will introduce scattered showers and tstms late tonight into Friday. ATLANTIC OCEAN... South-southwesterly flow prevails over the SW North Atlc with a favorable upper level divergent environment generally W of 70W with scattered to numerous showers and scattered tstms occurring N of 23N W of 72W. This activity is focused east of a surface trough analyzed across the Florida peninsula from offshore of Jacksonville near 30N80W to Lake Okeechobee to a 1007 mb low centered across the Florida Straits near 24N82W. Farther east... remnant energy from a weakened tropical wave is analyzed as a surface trough extending from Puerto Rico near 19N67W to 26N63W. Widely scattered showers and isolated tstms are occurring from 20N-26N between 56W-66W. This activity links up with the western extent of a stationary front that enters the discussion area near 32N39W to 26N45W to 25N60W. Scattered showers and tstms are occurring within 150 nm either side of the front. Elsewhere...a broad surface ridge anchored by a 1020 mb high centered near 25N26W prevails across the eastern Atlc. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN