000 AXNT20 KNHC 052320 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 720 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... Tropical Storm Nate is centered near 14.9N 84.3W at 05/2100 UTC or about 35 nm west-northwest of Puerto Lempira Honduras, moving north-northwest at 9 kt. Estimated minimum central pressure is 1000 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Scattered to numerous moderate and scattered strong convection is from 11N-22N between 73W-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 its axis from 15N33W to 09N36W, moving west at 10-15 kt. The wave has remained low-amplitude since emerging off the African coast several days ago. An ASCAT pass this morning indicated fresh to strong low-level cyclonic winds focused around the wave's axis with strong to near gale force southerly winds noted south of the ITCZ. Scattered moderate convection is from 07N-14N between 28W-40W. A tropical wave extends its axis from 18N41W to 09N48W, moving west at 10-15 kt. The wave coincides with troughing at 700 mb between 40W-50W. Isolated moderate convection is from 10N-14N between 45W-53W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 08N13W to 07N18W. The ITCZ extends from 07N18W to 09N35W to 11N47W. 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 most the basin this 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 to the Florida Big Bend region. The troughing supports a 1006 mb low centered across the Florida Straits near 24N83W. A surface trough extends to the south across western Cuba and to the northeast to near central Florida and then into the west Atlantic. Scattered moderate convection is observed along and south of the trough affecting the central and southern portions of the Florida Peninsula, the Florida Straits and Keys, and adjacent Gulf waters south of 27N and east of 84W. The remainder of the basin is under the influence of relatively drier northeasterly flow aloft and fresh to strong easterly winds on the southern periphery of surface ridging anchored across the southeast CONUS. The low and associated trough are 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... The primary focus remains across the western Caribbean and Central America is Tropical Storm Nate. Please refer to the section above for details. In addition, a surface trough embedded within a low pressure centered over the Florida Straits extends across western Cuba into the Caribbean waters. This feature is also enhancing convection across the area west of 80W. To the east, a surface trough extends from the northern coast of Puerto Rico near 18N66W to across the Atlantic waters providing focus for scattered showers and thunderstorms across the island and adjacent waters. This activity is supported aloft by an upper-level low centered near 12N64W, and associated upper-level trough that extends north to over Puerto Rico. Outside of the influence of Tropical Storm Nate, moderate to occasional fresh trades prevail east of 72W. ...HISPANIOLA... Currently skies remain mostly fair across the island. Surface troughing to the east is approaching the Mona Passage region and an upper-level trough currently over Puerto Rico will introduce scattered showers and thunderstorms late tonight into Friday to the area. ATLANTIC OCEAN... South-southwesterly flow prevails over the west Atlantic with a favorable upper-level divergent environment generally west of 70W enhancing scattered to numerous showers and thunderstorms occurring mainly north of 26N. This activity is focused east of a surface trough analyzed across the Florida peninsula from offshore of Jacksonville near 29N81W to 30N80W. To the east, remnant energy from a weakened tropical wave is analyzed as a surface trough extending from Puerto Rico near 19N67W to 26N61W. Scattered showers and thunderstorms are occurring from 20N-24N between 57W-65W. This activity links up with the western extent of a stationary front that enters the discussion area near 32N38W to 24N56W. Scattered showers and thunderstorms are occurring within 150 nm either side of the front. Elsewhere, a broad surface ridge anchored by a 1020 mb high centered near 24N30W prevails across the eastern Atlantic. For additional information please visit http://www.hurricanes.gov/marine $$ ERA