000 AXNT20 KNHC 111741 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT APR 11 2015 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 08N13W TO THE EQUATOR NEAR 23W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS ALONG THE EQUATOR FROM 23W TO 28W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM THE EQUATOR TO 04N BETWEEN 06W-11W. SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 04N BETWEEN 40W-52W. ...DISCUSSION... GULF OF MEXICO... WESTERLY FLOW ALOFT PREVAILS OVER MUCH OF THE GULF BASIN THIS AFTERNOON WITH WATER VAPOR IMAGERY INDICATING A COUPLE OF WEAK MID-LEVEL SHORTWAVE TROUGHS PROGRESSING EAST-NORTHEASTWARD...ONE LOCATED OVER THE NE GULF WATERS NEAR 29N86W AND THE OTHER OVER EXTREME SOUTHERN TEXAS NEAR 27N98W. THE PARENT TROUGH CURRENTLY OVER THE NE CONUS SUPPORTS A COLD FRONT ANALYZED FROM THE FLORIDA PANHANDLE NEAR 30N85W SW TO 30N88W WHERE THE FRONT BECOMES STATIONARY TO THE TEXAS COAST NEAR CORPUS CHRISTI. GIVEN THE SURFACE FRONTAL BOUNDARY AND FAVORABLE MIDDLE TO UPPER LEVEL DYNAMICS IN PLACE...SCATTERED SHOWERS AND TSTMS ARE OCCURRING ACROSS THE NORTHWESTERN HALF OF THE BASIN NW OF A LINE FROM THE FLORIDA BIG BEND TO THE MEXICO COAST NEAR TUXPAN. OTHERWISE... GENTLE TO OCCASIONALLY MODERATE EAST-SOUTHEASTERLY BREEZE CONDITIONS ARE EXPECTED TO CONTINUE INTO SUNDAY AS THE FRONT STALLS ACROSS THE NORTHERN GULF WATERS AND BECOMES DIFFUSE BY EARLY SUNDAY. THEREAFTER...SE RETURN FLOW WILL FULLY ESTABLISH ITSELF ACROSS THE BASIN FOR THE BEGINNING OF EARLY NEXT WEEK. CARIBBEAN SEA... MOST OF THE CARIBBEAN IS INFLUENCED BY UPPER LEVEL SOUTHWESTERLY FLOW TO THE EAST OF AN UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM OVER THE NW CARIBBEAN TO AN UPPER LEVEL LOW CENTERED WELL SOUTH OF CENTRAL AMERICA NEAR 04N91W. THE MAJORITY OF THIS FLOW REMAINS RELATIVELY DRY AND STABLE ALOFT WITH SKIES MOSTLY CLEAR THIS AFTERNOON. A FEW PASSING ISOLATED SHOWERS HOWEVER CANNOT BE RULED OUT ACROSS COASTAL WESTERN PANAMA AND COSTA RICA WHERE CLOUDINESS IS ENHANCED SLIGHTLY ON VISIBLE SATELLITE IMAGERY WITHIN MAXIMUM LOW-LEVEL CONVERGENCE. ...HISPANIOLA... MOSTLY CLEAR SKIES PREVAIL ACROSS THE ISLAND CURRENTLY AS WEST- SOUTHWESTERLY FLOW PERSISTS ALOFT. GIVEN INCREASED DAYTIME HEATING AND INSTABILITY...ISOLATED SHOWERS AND TSTMS ARE POSSIBLE THROUGH THE AFTERNOON AND EVENING HOURS. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE NE CONUS THAT SUPPORTS A COLD FRONT ANALYZED FROM THE MID-ATLC COAST TO LOW PRESSURE CENTERED IN EAST-CENTRAL GEORGIA AND ANOTHER COLD FRONT EXTENDING SW FROM THE LOW TO THE FLORIDA PANHANDLE. WHILE THE FRONT REMAINS WEST OF THE SW NORTH ATLC REGION AT THIS TIME...PRE-FRONTAL LOW-LEVEL CONVERGENCE ASSOCIATED WITH A SURFACE TROUGH OFFSHORE OF THE CAROLINAS IS GENERATING SCATTERED SHOWERS AND TSTMS WITHIN 90 NM EITHER SIDE OF A LINE FROM 36N70W TO 31N78W. ISOLATED SHOWERS LINGER TO THE W-SW OF THAT LINE MOVING OFFSHORE OF NORTHERN FLORIDA AND COASTAL GEORGIA. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER MOSTLY CLEAR SKIES AND FAIR CONDITIONS AS A SURFACE RIDGE AXIS EXTENDS FROM A 1028 MB HIGH NEAR 30N50W TO THE NW BAHAMAS NEAR 27N79W. FARTHER EAST...WHILE THE RIDGING HOLDS IN PLACE...A PAIR OF SURFACE TROUGHS ARE ANALYZED ON THE SOUTHWESTERN PERIPHERY OF THE HIGH. THE FIRST IS FROM 22N54W TO 25N54W WITH ISOLATED SHOWERS OCCURRING WITHIN 120 NM EITHER SIDE OF THE TROUGH AXIS...AND THE SECOND IS FROM 21N64W TO 25N64W WITH ISOLATED SHOWERS AND TSTMS OCCURRING FROM 20N-26N BETWEEN 60W-66W. THIS AREA IS SLIGHTLY STRONGER DUE TO AN UPPER LEVEL LOW CENTERED IN THE VICINITY NEAR 27N63W. OTHERWISE...THE REMAINDER OF THE EASTERN AND CENTRAL ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE AXIS EXTENDING FROM A 1028 MB HIGH CENTERED WEST OF THE IBERIAN PENINSULA NEAR 39N14W SW TO 30N30W TO THE 1028 MB HIGH CENTERED NEAR 30N50W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN