000 AXNT20 KNHC 250607 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 AM EDT Wed Oct 25 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 0000 UTC surface analysis and satellite imagery through 0545 UTC. ...TROPICAL WAVES... A tropical wave is E of the Lesser Antilles with axis extending from 18N56W to 06N57W. Interaction of the wave with an elongated upper level trough across the E Caribbean with base extending into S America is maintaining the wave nearly stationary. Satellite derived data show the wave is in a region of strong vertical wind shear. However, abundant low to middle level moisture and upper level diffluent between the trough and a broad ridge over the central Atlc support scattered moderate convection and isolated tstms from 10N-19N between 49W-61W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 11N16W to 10N20W. The Intertropical Convergence Zone axis extends from 10N20W to 08N30W to 05N52W. Scattered moderate convection and isolated tstms are from 03N-15N between 30W-49W and from 05N-10N E of 19W. ...DISCUSSION... GULF OF MEXICO... A vigorous middle to upper level trough is over the Great Lakes and Mississippi River valley with a broad base dipping southward to near 27N over the northern Gulf. The deep layered trough supports a cold front extending from central Florida near 26N81W SW to the Yucatan peninsula near 21N87W to western Guatemala. Scattered showers and isolated tstms are occurring within 120 nm E of the front as it continues to move eastward while isolated showers are within 210 nm W of the boundary. Fresh to strong northerly winds associated with the passage of the front are occurring mainly W of 90W and are expected to gradually decrease in areal coverage and be confined to the Bay of Campeche by Wednesday night. Otherwise, surface high pressure continues to build across the Gulf today into Thursday. CARIBBEAN SEA... A broad upper level ridge over the western Caribbean continues to provide an overall diffluent environment aloft. Underneath this diffluent flow aloft, a 1006 mb low is centered along the coastline of Nicaragua near 13N83W, which is supporting numerous heavy showers and scattered tstms across Nicaragua and scattered heavy showers and tstms elsewhere in the W Caribbean W of 80W. The convection extends farther SE and covers the region S of 13N between 73W and 80W. A deep layered trough covers the remainder basin with water vapor imagery showing strong subsidence, which is supporting fair weather. In the farther E Caribbean, proximity of a tropical wave with axis near 56W support scattered to isolated showers across the Windward Islands. A cold front currently across the SE Gulf of Mexico will move into the NW Caribbean today shifting winds northerly and increasing them into fresh to strong breeze levels through Thursday. Otherwise, moderate to fresh trades prevail across the basin. ...HISPANIOLA... Dry air aloft within northerly flow will support fair weather across the island through today and Thursday. Moderate trades are expected to persist. ATLANTIC OCEAN... A middle to upper level trough continues to progress eastward out of the Great Lakes and Mississippi River valley region towards the eastern US seaboard this morning. The trough supports a cold front extending from 31N77W to central Florida near Cape Canaveral. Scattered showers and isolated tstms are occurring ahead of the front within 210 nm. The remainder of the SW North Atlc is under the influence of a surface ridge anchored by a 1029 mb high centered near 38N58W. Within the southern periphery of this ridge, a stationary front extends from 30N33W to 26N41W where it starts to dissipate. A surface trough also extends from 26N59W to 21N63W. Scattered showers and tstms are occuring from 22N-29N between 51W-58W. A weak surface ridge is elsewhere. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos