000 AXNT20 KNHC 041745 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST MON NOV 04 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 10N14W TO 08N18W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N18W TO 03N26W TO 03N38W TO 02N45W. ISOLATED MODERATE CONVECTION IS FROM 02N-10N BETWEEN 13W-25W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL ANTICYCLONIC FLOW IS NOTED ON WATER VAPOR IMAGERY OVER MUCH OF THE GULF BASIN THIS AFTERNOON PROVIDING AN OVERALL STABLE ENVIRONMENT ALOFT. THE UPPER LEVEL RIDGE SUPPORTS SURFACE RIDGING EXTENDING FROM THE MID-ATLC SW OVER THE SE CONUS TO EAST- CENTRAL MEXICO NEAR 21N98W. A RELATIVELY STRONG PRESSURE GRADIENT EXISTS BETWEEN LOWER PRESSURE ACROSS THE CENTRAL CARIBBEAN SEA AND THE RIDGE PROVIDING FOR NE TO E WINDS IN THE RANGE OF 20 TO 25 KT E OF 90W. W OF 90W...E WINDS VEER SOUTHEASTERLY ACROSS THE NW GULF AND REMAIN IN THE RANGE OF 10 TO 20 KT WITH A SMALL POCKET OF 20 TO 25 KT POSSIBLE N OF 27N THROUGH THE AFTERNOON AND EVENING HOURS AS RETURN FLOW CONTINUES INTO AN AREA OF DEVELOPING LOW PRESSURE ACROSS THE CENTRAL AND SOUTHERN U.S. PLAINS. BY LATE WEDNESDAY...THE PRESSURE GRADIENT ACROSS THE EASTERN GULF IS FORECAST TO RELAX SOMEWHAT WITH THE NEXT COLD FRONT EXPECTED TO EMERGE OFF THE TEXAS AND LOUISIANA COASTS BY LATE WEDNESDAY INTO EARLY THURSDAY. CARIBBEAN SEA... AN UPPER LEVEL LOW IS CENTERED OVER THE NW CARIBBEAN NEAR 21N83W THAT EXTENDS A TROUGH AXIS SW TO ANOTHER BROADER UPPER LEVEL LOW CENTERED OVER GUATEMALA NEAR 15N90W. MIDDLE TO UPPER LEVEL LIFTING DYNAMICS ASSOCIATED WITH THE UPPER LEVEL LOW CONTINUES TO GENERATE ISOLATED SHOWERS AND TSTMS ACROSS THE NW CARIBBEAN N OF 17N W OF 80W...AND IN THE VICINITY OF THE GULF OF HONDURAS. FARTHER EAST...THE REMAINDER OF THE CENTRAL AND EASTERN CARIBBEAN ARE UNDER THE INFLUENCE OF AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 18N73W. AT THE SURFACE ON THE WESTERN PERIPHERY OF THE UPPER LEVEL RIDGE WHERE DIFFLUENCE IS MAXIMIZED...A 1009 MB LOW IS CENTERED NEAR 17N75W. BROAD FRONTAL TROUGHING EXTENDS NORTHEAST FROM THE LOW ACROSS EASTERN CUBA...HISPANIOLA...AND A LARGE PORTION OF THE SW NORTH ATLC FOCUSED ALONG A SURFACE TROUGH ANALYZED FROM THE LOW CENTER TO 20N73W TO BEYOND 24N67W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING N OF 15N BETWEEN 68W-77W IN ASSOCIATION WITH THE SURFACE LOW AND TROUGH AXIS. EAST OF 70W...NORTHERLY FLOW DOMINATES ON THE EASTERN PERIPHERY OF THE UPPER LEVEL ANTICYCLONE WITH MIDDLE TO UPPER LEVEL MOISTURE ADVECTING SOUTHWARD OVER THE EASTERN CARIBBEAN. WITH OVERALL LOW-LEVEL MOISTURE CONVERGENCE OF E-SE WINDS EAST OF THE AFOREMENTIONED SURFACE TROUGH AXIS...WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING N OF 13N BETWEEN 59W-68W. FINALLY...THE MONSOON TROUGH AXIS IS ANALYZED FROM COSTA RICA ALONG 10N TO 11N78W AND IS PROVIDING FOCUS FOR A ISOLATED SHOWERS S OF 12N W OF 75W THIS AFTERNOON. HISPANIOLA... CURRENTLY THE ISLAND IS UNDER THE INFLUENCE OF AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 18N73W. AT THE SURFACE...A 1009 MB LOW IS CENTERED SW OF THE ISLAND NEAR 17N75W THAT REMAINS NEARLY STATIONARY WITH A SURFACE TROUGH ANALYZED NE ACROSS WESTERN PORTIONS OF HAITI TO BEYOND 22N70W. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE ONGOING PRIMARILY ACROSS THE ADJACENT COASTAL WATERS OF HISPANIOLA...INCLUDING THE WINDWARD PASSAGE. WITH AMPLE MIDDLE TO UPPER LEVEL DIFFLUENCE AND A WEAK CONVERGENT SURFACE BOUNDARY FOR THE ATMOSPHERE TO WORK WITH...SHOWERS AND TSTMS ARE EXPECTED TO CONTINUE THROUGH TUESDAY UNTIL THE SURFACE LOW DRIFTS WESTWARD AND THE FRONTAL BOUNDARY TO THE NORTH ACROSS THE SW NORTH ATLC BECOMES MORE DIFFUSE. WITH MAXIMUM DAYTIME HEATING AND INSTABILITY OCCURRING DURING THE LATE AFTERNOON AND EARLY EVENING HOURS...CONVECTION IS FORECAST TO PEAK DURING THIS TIME EACH OF THE NEXT FEW DAYS. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL TROUGH AXIS EXTENDS OVER THE WESTERN NORTH ATLC FROM 39N63W TO A BASE NEAR 30N74W THAT SUPPORTS A COLD FRONT ANALYZED FROM 32N62W TO 29N68W WHERE IT BECOMES STATIONARY TO THE CENTRAL BAHAMAS NEAR 25N77W TO WESTERN CUBA NEAR 23N81W. ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THE FRONT. A PRE-FRONTAL SURFACE TROUGH IS ANALYZED TO THE SOUTHEAST OF THE FRONT FROM 31N63W TO 24N67W TO WESTERN HISPANIOLA NEAR 20N73W. A LARGE AREA OF FRONTAL TROUGHING IS NOTED ACROSS THE SW NORTH ATLC AND THIS AREA OF RELATIVELY WEAKER LOW PRESSURE IS PROVIDING FOR SCATTERED SHOWERS AND ISOLATED TSTMS N OF 18N BETWEEN 53W-78W...REMAINING GENERALLY IN THE VICINITY OF AND SOUTH OF THE FRONTAL BOUNDARY. OTHERWISE... THE REMAINDER OF THE SW NORTH ATLC NW OF THE FRONT IS UNDER THE INFLUENCE OF SURFACE RIDGING BUILDING IN FROM THE SE CONUS PROVIDING BRISK NE WINDS IN THE RANGE OF 20 TO 30 KT FROM BERMUDA WESTWARD TO THE CAROLINAS...GEORGIA...AND FLORIDA PENINSULA COAST THIS AFTERNOON. FARTHER EAST...A VERY BROAD COMPLEX UPPER LEVEL LOW IS CENTERED NEAR 23N45W THAT SUPPORTS A SURFACE TROUGH ANALYZED FROM 11N45W TO 19N43W. ISOLATED SHOWERS ARE OCCURRING WITHIN 180 NM EITHER SIDE OF THE SURFACE TROUGH AXIS. THE UPPER LEVEL LOW ITSELF IS GENERATING MULTI-LAYERED CLOUDINESS AND POSSIBLE ISOLATED SHOWERS ACROSS A LARGE PORTION OF THE EASTERN ATLC EAST OF A LINE FROM 10N28W TO 22N41W... PRIMARILY IN THE AREA OF MAXIMUM MIDDLE TO UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE UPPER LEVEL LOW. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN