000 AXNT20 KNHC 252348 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI APR 25 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO 01N15W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 01N15W TO THE EQUATOR NEAR 16W. ISOLATED MODERATE CONVECTION IS FROM 01N-04N BETWEEN 33W-47W. ...DISCUSSION... GULF OF MEXICO... MOSTLY WESTERLY FLOW ALOFT IS NOTED ON WATER VAPOR IMAGERY OVER MUCH OF THE GULF WHICH IS PROVIDING FOR OVERALL FAIR CONDITIONS AND MOSTLY CLEAR SKIES THIS EVENING. FURTHER PROMOTING THE FAIR WEATHER IS A WEAK SURFACE RIDGE ANCHORED BY A 1017 MB HIGH CENTERED ACROSS THE NE GULF NEAR 27N85W. A WEAK FRONTAL BOUNDARY...CURRENTLY A COLD FRONT ACROSS THE SE CONUS AND STATIONARY ACROSS LOUISIANA INTO COASTAL SE TEXAS...CONTINUES TO REMAIN A FAIRLY BENIGN FEATURE DUE TO MOST OF THE MIDDLE TO UPPER LEVEL DYNAMICS LOCATED WELL NORTH OF THE BASIN OVER THE MID-ATLC REGION THIS EVENING. THE FRONT IS EXPECTED TO REMAIN WEAK AND BRIDGE THE SURFACE RIDGING ACROSS THE EASTERN GULF AND ANOTHER SURFACE RIDGE LOCATED ACROSS THE LOWER MISSISSIPPI RIVER VALLEY THAT IS FORECAST TO SLIDE EASTWARD TO THE CAROLINAS BY EARLY SATURDAY. THEREAFTER FOR THE REMAINDER OF SATURDAY INTO SUNDAY...SE SURFACE WINDS ARE EXPECTED TO PERSIST THROUGH THE WEEKEND INTO MONDAY GRADUALLY INCREASING INTO THE RANGE OF 15 TO 20 KT BY LATE SATURDAY AHEAD OF A DEVELOPING AREA OF LOW PRESSURE ACROSS THE CENTRAL AND SOUTHERN PLAINS. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE SW CARIBBEAN THIS EVENING PROVIDING MUCH OF THE BASIN WITH WESTERLY FLOW ALOFT WITH WATER VAPOR IMAGERY INDICATING RELATIVELY DRY AIR AND STABLE CONDITIONS. THE ONLY SIGNIFICANT WEATHER OCCURRING REMAINS ACROSS THE GREATER ANTILLES AS A SURFACE TROUGH EXTENDS FROM THE CENTRAL ATLC ALONG 22N60W TO THE NORTHERN COAST OF HISPANIOLA NEAR 20N72W TO THE SOUTHEASTERN COAST OF CUBA NEAR 20N77W. WEAK LOW-LEVEL MOISTURE CONVERGENCE ALONG THE SURFACE TROUGH AXIS IN CONJUNCTION WITH MAXIMUM DIFFERENTIAL HEATING ACROSS CUBA AND HISPANIOLA IS GENERATING ISOLATED SHOWERS AND TSTMS WITHIN 75 NM EITHER SIDE OF A LINE FROM CENTRAL HISPANIOLA NEAR 19N71W TO WESTERN CUBA NEAR 23N81W. THE ONLY OTHER AREA OF CONCERN CONVECTIVELY SPEAKING IS A FEW WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING ACROSS THE SW CARIBBEAN AND INLAND PORTIONS OF NORTHERN COLOMBIA... PANAMA...AND COSTA RICA...S OF 11N BETWEEN 71W-84W. OTHERWISE... FAIR SKIES PREVAIL ACROSS THE REMAINDER OF THE CARIBBEAN THIS EVENING WITH TRADES PERSISTING IN THE RANGE OF 10 TO 20 KT...STRONGEST S OF 14N BETWEEN 65W-76W. ...HISPANIOLA... CURRENTLY ISOLATED SHOWERS AND TSTMS ARE OCCURRING ACROSS HISPANIOLA AS A SURFACE TROUGH REMAINS ANALYZED ACROSS THE NORTHERN COAST OF HISPANIOLA WESTWARD TO THE WINDWARD PASSAGE REGION THIS EVENING. IT IS LIKELY THAT PEAK DAYTIME HEATING AND INSTABILITY IS ENHANCING THIS ONGOING CONVECTION WHICH IS EXPECTED TO GRADUALLY DIMINISH THROUGH THE EVENING HOURS. MOISTURE ASSOCIATED WITH THIS BOUNDARY IS FORECAST TO BECOME DIFFUSE DURING THE UPCOMING WEEKEND. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE MID-ATLC STATES THIS EVENING WITH AXIS EXTENDING SOUTHWARD ALONG 77W TO A BROAD BASE NEAR 25N. AS A RESULT...LOWER PRESSURE AND BROAD TROUGHING IS ANALYZED OVER THE SW NORTH ATLC N OF 25N BETWEEN 74W-82W...HOWEVER MOST PRECIPITATION REMAINS ELEVATED WITH ISOLATED SHOWERS AND TSTMS OCCURRING FROM 23N-31N BETWEEN 70W-78W...AND LIKELY ENHANCED BY THE WEAK MID-LEVEL TROUGHING. FARTHER EAST...A DEEP LAYERED LOW IS CENTERED OVER THE NORTH-CENTRAL ATLC SUPPORTING A 982 MB LOW CENTERED NEAR 38N54W. THE MAIN COLD FRONT ASSOCIATED WITH THIS LOW EXTENDS INTO THE DISCUSSION AREA NEAR 32N47W CONTINUING SW TO 26N56W TO 24N64W. PRECIPITATION OCCURRING ALONG AND EAST OF THE FRONT REMAINS N OF 31N. A PRE-FRONTAL SURFACE TROUGH IS ANALYZED FROM 29N49W SW TO 22N60W TO THE WINDWARD PASSAGE REGION NEAR 20N74W. LOW-LEVEL MOISTURE CONVERGENCE IS OCCURRING ALONG THE SURFACE TROUGH GENERATING ISOLATED SHOWERS AND TSTMS WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A PRIMARY 1029 MB HIGH CENTERED NORTH OF THE MADEIRA ISLANDS NEAR 36N18W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN