000 AXNT20 KNHC 310546 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN OCT 30 2011 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 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 15N17W TO 12N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 12N20W TO 08N30W TO 04N51W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 01N-09N BETWEEN 17W-33W. ISOLATED MODERATE CONVECTION IS FROM 06N-11N BETWEEN 44W-56W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL TROUGH AXIS EXTENDS FROM THE MID-MISSISSIPPI RIVER VALLEY OVER WESTERN LOUISIANA AND THE TEXAS GULF COAST TO A BASE OVER EAST-CENTRAL MEXICO NEAR 23N99W. THE MIDDLE TO UPPER LEVEL TROUGH REMAINS EMBEDDED WITHIN DRY AIR AND MUCH OF THE GULF THIS EVENING REMAINS UNDER DRY SOUTHWESTERLY FLOW ALOFT EAST OF THE TROUGH AXIS. HOWEVER FARTHER EAST...AS OF 31/0300 UTC A STATIONARY FRONTAL BOUNDARY EXTENDS FROM THE FLORIDA STRAITS NEAR 24N80W TO 23N85W TO THE NE COAST OF THE YUCATAN PENINSULA NEAR 21N87W. LOW TO MIDDLE LEVEL MOISTURE ADVECTION NORTHWARD OVER THE WESTERN CARIBBEAN SEA CONTINUES TO LIFT IN THE VICINITY OF THE FRONT AND PROVIDE THE SE GULF AND SOUTHERN FLORIDA...INCLUDING THE FLORIDA KEYS AND FLORIDA STRAITS WITH WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS MAINLY S OF 27N E OF 88W. ISOLATED SHOWERS ARE ALSO NOTED ON MOSAIC DOPPLER RADAR IMAGERY N OF 27N E OF 86W...INCLUDING THE CENTRAL FLORIDA PENINSULA. ELSEWHERE ACROSS THE GULF TONIGHT...N TO NE WINDS AND GENERALLY FAIR CONDITIONS ARE EXPECTED. LOOKING AHEAD...AS THE MIDDLE TO UPPER LEVEL ENERGY ASSOCIATED WITH THE TROUGHING MOVES EASTWARD...THE FRONT IS FORECAST TO EXIT THE GULF WATERS BY LATE MONDAY AS SURFACE RIDGING AND NE TO E WINDS PREVAIL THROUGH WEDNESDAY. CARIBBEAN SEA... THE WESTERN CARIBBEAN W OF 78W FALLS UNDER THE INFLUENCE OF AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED OVER THE W ATLC NEAR 28N59W. THE UPPER LEVEL RIDGE AXIS EXTENDS SW FROM THE CENTER OVER EASTERN CUBA NEAR 21N78W TO 16N85W. WEST OF THE UPPER LEVEL RIDGE AXIS...LOW TO MIDDLE LEVEL MOISTURE CONTINUES TO ADVECT NORTHWARD TOWARD A STATIONARY FRONT ANALYZED FROM THE YUCATAN CHANNEL TO NEAR 18N86W. THIS FRONT ALONG WITH A SURFACE TROUGH FROM 10N80W TO 20N84W IS PROVIDING FOCUS FOR SCATTERED SHOWERS AND TSTMS OVER A LARGE PORTION OF THE WESTERN CARIBBEAN AND CENTRAL AMERICA W OF 78W. UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE UPPER LEVEL RIDGE CONTINUES TO ENHANCE STRONGER CONVECTION THIS EVENING S OF 14N W OF THE SURFACE TROUGH ALONG 81W. THIS STRONGER PRECIPITATION WILL BRING HEAVY RAINFALL AND POTENTIAL FLOODING TO EASTERN NICARAGUA...COSTA RICA...AND PANAMA OVERNIGHT. FARTHER EAST...AN UPPER LEVEL LOW IS CENTERED NEAR 14N71W. LOW-LEVEL MOISTURE CONVERGENCE AND ADDED MIDDLE TO UPPER LEVEL DIFFLUENCE IN ASSOCIATION WITH THE UPPER LEVEL LOW IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS OVER PORTIONS OF THE EASTERN CARIBBEAN FROM 12N-17N BETWEEN 62W-71W...AND S OF 13N BETWEEN 68W-76W. ATLANTIC OCEAN... MOIST SOUTHWESTERLY MIDDLE TO UPPER LEVEL FLOW IS NOTED ON WATER VAPOR IMAGERY BETWEEN AN UPPER LEVEL TROUGH PROGRESSING ACROSS THE NW GULF OF MEXICO AND A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 28N59W. THIS UPPER LEVEL PATTERN SUPPORTS A STATIONARY FRONT ANALYZED FROM 32N61W SW ALONG 27N70W TO THE FLORIDA STRAITS NEAR 24N80W AND INTO THE SE GULF OF MEXICO. LOW-LEVEL CONVERGENCE IN THE VICINITY OF THE FRONT CONTINUES TO GENERATE WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 90 NM SOUTH AND EAST...AND WITHIN 180 NM NORTH AND WEST OF THE BOUNDARY. THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF THE SUBTROPICAL HIGH ANCHORED BY A 1026 MB HIGH CENTERED NEAR 32N36W. CONDITIONS ARE EXPECTED TO REMAIN GENERALLY FAIR DURING THE NEXT 24 TO 36 HOURS...HOWEVER EMBEDDED WITHIN THE RIDGING...A SURFACE TROUGH IS ANALYZED FROM 14N51W TO 21N47W AS A REFLECTION OF AN UPPER LEVEL LOW CENTERED NEAR 18N48W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING FROM 17N-21N BETWEEN 40W-44W...AND FROM 19N-22N BETWEEN 44W-52W. A RECENT ASCAT PASS AROUND 31/0044 UTC DEPICTED 20-25 KT NE TO E WINDS NORTH OF THE SURFACE TROUGH FROM 18N-26N BETWEEN 38W-55W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN