000 AXNT20 KNHC 032356 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST SUN NOV 03 2013 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. ...TROPICAL WAVES... NONE ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE COASTAL AREAS OF SIERRA LEONE NEAR 7N12W AND ENDS NEAR 5N14W. THE ITCZ CONTINUES FROM 5N14W TO 4N25W TO 5N33W TO THE EQUATOR AT 43W AND TO THE COAST OF BRAZIL NEAR 2S45W. ISOLATED MODERATE CONVECTION IS FROM 4N- 11N BETWEEN 16W-24W. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE AXIS EXTENDS SW FROM THE GREAT LAKES THROUGH THE LOWER MISSISSIPPI VALLEY INTO THE WESTERN GULF OF MEXICO AND INLAND NEAR TAMPICO MEXICO. WINDS WEST OF THE RIDGE AXIS ARE GENERALLY A LIGHT BREEZE FROM THE EAST-SOUTHEAST WHILE FRESH TO STRONG NORTHEAST WINDS CONTINUE TO PREVAIL IN THE OFFSHORE WATERS EAST OF THE RIDGE AXIS. THE 1602 UTC ASCAT-B PASS SHOWED NEAR GALE FORCE NORTHEAST WINDS FUNNELING INTO THE YUCATAN CHANNEL BEHIND A COLD FRONT THAT STRETCHES FROM CENTRAL CUBA TO THE GULF OF HONDURAS. AVAILABLE OBSERVATIONS SHOW THESE WINDS HAVE NOW DIMINISHED. AN UPPER TROUGH STRETCHES FROM THE EAST COAST OF FLORIDA THROUGH THE STRAITS OF FLORIDA TO AN UPPER LOW OVER THE NW CARIBBEAN. THE MOST ABUNDANT MOISTURE OVER THE GULF LIES NEAR AND SOUTH OF THIS TROUGH. ISOLATED MODERATE CONVECTION IS OVER THE YUCATAN CHANNEL FROM 20N-22N BETWEEN 83W-87W. OVER THE REMAINDER OF THE GULF...STRONG SUBSIDENCE PREVAILS ON THE NORTHWEST SIDE OF THE UPPER TROUGH. THE SHORT TERM FORECAST CALLS FOR THE PRESSURE GRADIENT TO ALIGN NORTH TO SOUTH ACROSS THE EASTERN GULF...ALLOWING THE WINDS TO REMAIN A FRESH TO STRONG BREEZE BUT SHIFTING MORE EASTERLY WITH WEAKER SOUTHEASTERLY FLOW IN THE NORTHWESTERN GULF AND BECOMING LIGHT AND VARIABLE IN THE SOUTHWESTERN GULF. THE UPPER LOW IN THE NW CARIBBEAN IS EXPECTED TO WEAKEN AND SLOWLY SHIFT NORTHWESTWARD INTO THE SOUTHERN GULF...ALLOWING FOR CONTINUED CONVECTION OVER W CUBA AND THE YUCATAN CHANNEL. CARIBBEAN SEA... A SURFACE COLD FRONT EXTENDS FROM CENTRAL CUBA NEAR 22N80W TO THE GULF OF HONDURAS NEAR 16N88W. EXPECT THE COLD FRONT TO DISSIPATE OVER THE NEXT 24 HOURS. AN UPPER LOW LIES OVER THE NW CARIBBEAN NEAR 18N83W. ISOLATED MODERATE CONVECTION CAN BE FOUND WITHIN 200 NM E AND 90 NM W OF THE UPPER LOW POSITION AS WELL AS IN THE AREA FROM 20N-22N BETWEEN 83W-87W...INCLUDING THE YUCATAN CHANNEL. AS STATED ABOVE...THIS LOW IS EXPECTED TO WEAKEN AS MOVE NORTHWESTWARD INTO THE SOUTHERN GULF OF MEXICO OVER THE NEXT FEW DAYS. SHOWER AND THUNDERSTORM ACTIVITY SHOULD CONTINUE TO CONCENTRATE NEAR THIS SYSTEM FOR THE NEXT DAY. A SURFACE TROUGH EXTENDS ALONG 75W NORTHWARD TO 1008 MB LOW PRESSURE NEAR 17N75W AND THEN THROUGH THE WINDWARD PASSAGE. ISOLATED MODERATE CONVECTION IS OVER THE E CARIBBEAN FROM 10N TO BEYOND 20N BETWEEN 64W-70W. ANOTHER SURFACE TROUGH EXTENDS FROM N OF PUERTO RICO AT 23N66W TO THE MONA PASSAGE AT 19N67W. IT LIES IN THE VICINITY OF AN UPPER ANTICYCLONE CENTERED NEAR 17N68W WHICH IS SUPPLYING LIFT TO THE LOW LEVEL MOISTURE OVER THE EASTERN CARIBBEAN. SCATTERED MODERATE CONVECTION CONTINUES OVER PUERTO RICO AND THE LEEWARD ISLANDS N OF 15N BETWEEN 60W-67W. THE ANTICYCLONE ALOFT IS FORECAST TO SHIFT WESTWARD AND TAKE THE BEST UPPER LEVEL DIFFLUENT FLOW...AND CHANCE OF CONVECTION...WITH IT. HISPANIOLA... THE AFOREMENTIONED UPPER LEVEL ANTICYCLONE IN THE CARIBBEAN IS AIDING THE ISOLATED MODERATE CONVECTION OVER HISPANIOLA. EXPECT THIS CONVECTION TO PERSIST FOR THE NEXT 24 HOURS WITH THE POSSIBILITY OF LOCALIZED FLOODING AS THE ANTICYCLONE MOVES WESTWARD SOUTH OF HISPANIOLA. ATLANTIC OCEAN... A COLD FRONT EXTENDS FROM 32N69W THROUGH THE BAHAMAS TO CENTRAL CUBA NEAR 22N80W. SCATTERED SHOWERS CONTINUE WITHIN 90 NM OF THE FRONT. TWO SURFACE TROUGHS ARE N OF THE CARIBBEAN SEA PRODUCING ISOLATED MODERATE CONVECTION OVER THE TURKS AND CAICOS S OF 23N BETWEEN 70W-73W...AND SCATTERED MODERATE CONVECTION N OF PUERTO RICO FROM 18N-21N BETWEEN 63W-68W. A 1030 MB HIGH IS CENTERED NEAR THE AZORES AT 38N33W. THIS HIGH IS DRIVING THE PRIMARILY EASTERLY FLOW FOUND OVER THE ATLANTIC EAST OF 60W. IN THE TROPICS...A SURFACE TROUGH EXTENDS FROM 18N41W TO 65N44W. IT IS ASSOCIATED WITH AN UPPER LEVEL LOW CENTERED NEAR 15N42W. DEEP MOISTURE COUPLED WITH UPPER LEVEL DIFFLUENCE E OF THE CENTER IS PRODUCING ISOLATED MODERATE CONVECTION FROM 10N-16N BETWEEN 40W- 44W. EXPECT THE W ATLANTIC COLD FRONT TO MOVE E OVER THE NEXT 24 HOURS...WITH SHOWERS AND ISOLATED THUNDERSTORMS CONTINUING...AS HIGH PRESSURE MOVES EASTWARD INTO THE FAR EASTERN ATLANTIC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ SCHAUER