000 AXNT20 KNHC 131112 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI MAY 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...ITCZ... FROM SOUTHERN COASTAL SIERRA LEONE TO 4N20W 2N30W 2N44W... BECOMING INDISTINCT. SCATTERED MODERATE RAINSHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE IN THE ATLANTIC OCEAN FROM 5S TO 6N BETWEEN 20W AND 50W. ISOLATED MODERATE RAINSHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE FROM 2N TO 7N TO THE EAST OF 16W. ...DISCUSSION... GULF OF MEXICO... CYCLONIC FLOW FROM A DEEP LAYER TROUGH SPANS THE U.S.A. MIDWEST BETWEEN ILLINOIS AND COLORADO. THE TROUGH SUPPORTS A CENTRAL U.S.A. FRONTAL BOUNDARY...THAT IS FORECAST TO REACH THE TEXAS GULF COAST DURING THE NEXT 24 HOURS OR SO. UPPER LEVEL ANTICYCLONIC WIND FLOW MOVES FROM THE EASTERN PACIFIC OCEAN FROM 10N TO 30N BETWEEN 100W AND 120W...ACROSS MEXICO AND PARTS OF CENTRAL AMERICA INTO THE GULF OF MEXICO AND THE ADJACENT CARIBBEAN SEA. BROAD UPPER LEVEL WESTERLY AND NORTHWESTERLY FLOW COVERS THE GULF OF MEXICO. BROAD MIDDLE LEVEL TO UPPER LEVEL NORTHERLY FLOW THAT COVERS FLORIDA IS RELATED TO AN ATLANTIC OCEAN TROUGH. BROAD SURFACE ANTICYCLONIC FLOW COVERS THE AREA THAT IS TO THE NORTH OF 25N TO THE EAST OF 90W...MOVING AROUND A 1014 MB HIGH PRESSURE CENTER THAT IS NEAR 27N85W. ONE AREA OF RAIN IS WITHIN A 30 NM RADIUS OF 26N95W. CONVECTIVE DEBRIS CLOUDS ARE BETWEEN 84W AND 94W. A WEAK SURFACE TROUGH STRADDLES THE GULF COAST FROM SOUTHWESTERN LOUISIANA TO THE LOWER TEXAS COAST. CARIBBEAN SEA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 23N74W IN THE BAHAMAS...ACROSS EASTERN CUBA AND JAMAICA TO 13N79W IN THE SOUTHWESTERN CORNER OF THE AREA. ISOLATED MODERATE RAINSHOWERS TO POSSIBLE THUNDERSTORMS COVER THE AREA FROM 10N TO 17N BETWEEN 83W AND 90W IN CENTRAL AMERICA...IN BROAD SURFACE LOW PRESSURE AND UPPER LEVEL ANTICYCLONIC FLOW. STRONG RAINSHOWERS AND THUNDERSTORMS ARE IN THE WATERS AND COASTAL SECTIONS OF COLOMBIA AND PANAMA BETWEEN 75W AND 81W...AND FROM 9N TO 11N BETWEEN 70W AND 74W IN NORTHWESTERN VENEZUELA AND NORTHEASTERN COLOMBIA... IN BROAD MONSOONAL CYCLONIC FLOW. THE SURFACE PRESSURE GRADIENT IS WEAK ACROSS THE AREA. A SURFACE TROUGH EXTENDS FROM 17N72W TO 13N74W TO 10N76W. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION ARE TO THE EAST OF THE LINE THAT GOES FROM THE MONA PASSAGE TO 13N72W. ATLANTIC OCEAN... BROAD MIDDLE LEVEL TO UPPER LEVEL CYCLONIC FLOW COVERS THE AREA TO THE WEST OF 50W. IT IS POSSIBLE THAT MULTIPLE CYCLONIC CIRCULATION CENTERS ARE EMBEDDED IN THE LARGER-SCALE CYCLONIC FLOW...REALLY ONLY TO THE NORTH OF 30N TO THE WEST OF 50W. A 997 MB LOW PRESSURE CENTER IS NEAR 35N61W. A DISSIPATING FRONTAL BOUNDARY EVENTUALLY EXTENDS FROM THE CYCLONIC ENVELOPE ALONG 47W/48W PASSING THROUGH 32N TO 30N. RAINSHOWERS ARE POSSIBLE TO THE NORTH OF 32N45W 24N60W...TO SOUTHEASTERN CUBA... BEYOND 30N80W...AND ELSEWHERE WITHIN 240 NM ON EITHER SIDE OF 17N62W IN THE CARIBBEAN SEA TO 24N50W TO 32N39W. BROAD SURFACE ANTICYCLONIC FLOW IS TO THE NORTH OF 10N BETWEEN AFRICA AND THE DISSIPATING FRONTAL BOUNDARIES. BROAD UPPER LEVEL CYCLONIC FLOW IS TO THE NORTH OF 14N TO THE EAST OF 30W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT