000 AXNT20 KNHC 081747 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED OCT 08 2014 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. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE EASTERN ATLANTIC EXTENDING FROM 15N20W TO A 1011 MB SURFACE LOW NEAR 9N20W TO 7N21W MOVING WESTWARD AT 10-15 KT. SSMI TPW IMAGERY AND WATER VAPOR IMAGERY INDICATE THAT THE WAVE IS EMBEDDED IN AN ENVIRONMENT WITH HIGH DEEP LAYER MOISTURE AND COINCIDES WITH A DIFFLUENT ENVIRONMENT ALOFT. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 7N-14N BETWEEN 19W AND 25W. A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS EXTENDING FROM 16N45W TO 7N45W...MOVING W AT 10-15 KT. SSMI TPW IMAGERY INDICATE THIS WAVE IS EMBEDDED IN A LARGE AREA OF MODERATE MOISTURE. AN UPPER TROUGH TO THE NORTH OF THE WAVE IS PRODUCING WESTERLY UPPER LEVEL WINDS OVER THE NORTHERN PORTION OF THE WAVE. SCATTERED MODERATE CONVECTION IS FROM 12N TO 19N BETWEEN 42W AND 50W. SCATTERED SHOWERS ARE S OF 13N WITHIN 100 NM OF THE WAVE AXIS. A TROPICAL WAVE IS MOVING ACROSS THE EASTERN CARIBBEAN WITH AXIS EXTENDING FROM 19N66W TO 10N67W...MOVING W AT 15 KT. SSMI TPW SHOWS THIS WAVE IS EMBEDDED IN A AREA OF HIGH MOISTURE WHICH IS SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS PUERTO RICO AND SURROUNDING ISLANDS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF AFRICA NEAR 14N17W TO A 1011 SURFACE LOW NEAR 9N20W. THE ITCZ EXTENDS FROM THE SURFACE LOW NEAR 9N20W TO 12N40W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE AND SURFACE LOW...SCATTERED MODERATE CONVECTION IS FROM 5N-18N BETWEEN 26W-42W. ...DISCUSSION... GULF OF MEXICO... A BROAD MID TO UPPER LEVEL TROUGH REMAINS OVER THE EASTERN CONUS AND EXTENDS INTO THE NORTHERN GULF. AN UPPER LEVEL RIDGE IS OVER W MEXICO WITH SUBSIDENCE OCCURRING ACROSS MUCH OF E MEXICO AND THE W GULF BETWEEN THESE TWO FEATURES. DIFFLUENCE TO THE SOUTH AND EAST OF THE UPPER TROUGH CONTINUES TO PRODUCE CLOUD COVER AND SCATTERED SHOWERS FROM THE YUCATAN N TO 26N BETWEEN 82W AND 90W. A SURFACE TROUGH IS FROM 24N90W THROUGH THE BAY OF CAMPECHE TO THE MEXICO COAST NEAR 18N94W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 50 NM OF THIS TROUGH AXIS. OVER THE NEXT 24 HOURS THE UPPER TROUGH WILL LIFT OUT OF THE BASIN WHILE THE UPPER RIDGE SHIFTS WEST INTO THE BASIN. SUBSIDENCE BETWEEN THESE TWO FEATURES SHOULD LIMIT AREAS OF CONVECTION. HOWEVER...THE SURFACE TROUGH WILL REMAIN THE FOCUS FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS AS IT MOVES ACROSS THE W GULF AND REMAINS IN THE BAY OF CAMPECHE ON THURSDAY. CARIBBEAN SEA... SCATTERED MODERATE AND ISOLATED STRONG CONVECTION ARE ACROSS THE SW CARIBBEAN ASSOCIATED WITH A 1009 MB LOW CENTERED OVER WESTERN COSTA RICA NEAR 10N85W. A TROPICAL WAVE IS IN THE EASTERN CARIBBEAN...SEE THE TROPICAL WAVES SECTION ABOVE. DRY AIR IS LIMITING CONVECTION ACROSS THE GREATER ANTILLES WEST OF PUERTO RICO AND THE NW CARIBBEAN. ACROSS CUBA...HISPANIOLA...AND JAMAICA...DUST AND HAZE CONTINUE TO BE REPORTED. THIS HAZE AND DUST IS ASSOCIATED WITH A SAHARAN AIRMASS. SURFACE TRADE WINDS OF 10 TO 20 KT DOMINATE THE BASIN. OVER THE NEXT 24 HOURS...ENHANCED CONVECTION IS EXPECTED TO CONTINUE ACROSS THE SW CARIBBEAN IN THE PRESENCE OF UPPER LEVEL DIFFLUENCE AND THE SLOW MOVING SURFACE LOW. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE CENTRAL CARIBBEAN ALONG THE WESTWARD MOVING TROPICAL WAVE. A SURFACE TROUGH IN THE ATLANTIC APPROACHING THE LESSER ANTILLES MAY BRING AN INCREASE IN SHOWER AND THUNDERSTORMS ACTIVITY TO THOSE ISLANDS LATER ON THURSDAY AND ON FRIDAY. ...HISPANIOLA... DRY CONDITIONS AND HAZE CONTINUE ACROSS THE ISLAND IN THE PRESENCE OF SAHARAN AIR. MOISTURE WILL SLOWLY INCREASE TONIGHT AND THURSDAY AS A TROPICAL WAVE MOVES ACROSS THE AREA...AND A SURFACE TROUGH APPROACHES FROM THE WEST. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THURSDAY AND FRIDAY. ATLANTIC OCEAN... ASCENT ON THE SOUTH AND EASTERN SIDE OF A TROUGH OVER THE EASTERN CONUS CONTINUES TO ENHANCE CLOUD COVER AND PRODUCE ISOLATED SHOWERS AND THUNDERSTORMS FROM S FL ACROSS THE NORTHERN BAHAMAS AND NORTHEASTWARD TO NEAR 30N75W. A SURFACE TROUGH IS FROM 22N59W TO 14N58W. AN UPPER LOW IS OVER THIS SURFACE TROUGH NEAR 21N60W. SCATTERED MODERATE CONVECTION IS OCCURRING MAINLY W OF THE TROUGH FROM 14N TO 24N BETWEEN 52W AND 58W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE ALSO WITHIN 150 NM EAST OF THE TROUGH AXIS. OVER THE NEXT 24 HOURS EXPECT THE SURFACE TROUGH AND UPPER LOW TO SHIFT WEST WITH ONGOING CONVECTION. THE UPPER TROUGH OVER THE EASTERN CONUS WILL BEGIN TO LIFT AND SLIDE EAST. THIS SHOULD BRING A FOCUS OF CLOUD COVER AND SHOWERS EAST OF THE BAHAMAS BY THURSDAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO