000 AXNT20 KNHC 141744 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU MAY 14 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 07N16W TO 05N20W TO 05N26W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N26W TO 06N33W TO THE EQUATOR NEAR 47W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 01N-05N BETWEEN 01W- 15W...AND FROM 02N-08N BETWEEN 15W-34W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE WESTERN GULF WITH AXIS EXTENDING FROM OVER EASTERN TEXAS TO A BASE NEAR 24N93W. WHILE THE FRONTAL BOUNDARY ASSOCIATED WITH THE PARENT TROUGH OVER THE CENTRAL PLAINS REMAINS NEARLY STATIONARY ALONG 30N FROM THE FLORIDA BIG BEND TO EASTERN LOUISIANA... MIDDLE TO UPPER LEVEL DIFFLUENCE CONTINUE TO GENERATE CLOUDINESS AND ISOLATED SHOWERS N OF 21N BETWEEN 87W-93W ACROSS THE CENTRAL PORTION OF THE BASIN. OTHERWISE...AN UPPER LEVEL RIDGE IS CENTERED OVER THE WEST-CENTRAL FLORIDA PENINSULA NEAR 27N82W PROVIDING MOSTLY DRY AND STABLE CONDITIONS ALOFT E OF 86W... INCLUDING THE FLORIDA PENINSULA. LIKEWISE...DRIER AIR ALOFT IS ALSO NOTED WEST OF THE UPPER LEVEL TROUGH AXIS WITH MOSTLY CLEAR SKIES N OF 22N W OF 93W. GENTLE TO MODERATE E-SE WINDS ARE OCCURRING CURRENTLY ACROSS THE GULF AND ARE EXPECTED TO PREVAIL THROUGH LATE FRIDAY. SURFACE RIDGING IS EXPECTED TO ALSO PREVAIL THROUGH THE WEEKEND...HOWEVER A DEVELOPING AREA OF LOW PRESSURE ACROSS THE CENTRAL PLAINS ON SATURDAY WILL INCREASE THE E-SE SURFACE WINDS SLIGHTLY AS THE PRESSURE GRADIENT STRENGTHENS. CARIBBEAN SEA... WESTERLY FLOW ALOFT PREVAILS OVER THE CARIBBEAN THIS AFTERNOON ON THE SOUTHERN PERIPHERY OF AN UPPER LEVEL TROUGH AXIS EXTENDING EAST-WEST FROM 20N65W TO 19N79W. WATER VAPOR IMAGERY INDICATES DRIER AND MORE STABLE AIR MOVING SOUTHWARD IN ASSOCIATION WITH THE TROUGH AXIS...HOWEVER RELATIVELY DRY AND STABLE CONDITIONS ARE ALREADY IN PLACE OVER THE BASIN PROVIDING FOR MOSTLY CLEAR SKIES AND FAIR CONDITIONS AT THE SURFACE. THE MAIN IMPACT REMAINS THE FRESH TO STRONG TRADES GENERATED BY A STRENGTHENED PRESSURE GRADIENT ACROSS THE SOUTH-CENTRAL AND SW CARIBBEAN. THESE CONDITIONS ARE FORECAST TO PERSIST THROUGH THE WEEKEND AS HIGH PRESSURE ONCE AGAIN ANCHORS ACROSS THE SW NORTH ATLC REGION. ...HISPANIOLA... CURRENTLY...RELATIVELY CLEAR SKIES PREVAIL ACROSS THE ISLAND THIS AFTERNOON AS AN UPPER LEVEL TROUGH AND THE ASSOCIATED DRY AND STABLE AIR MOVES SOUTHWARD OVER THE ISLAND AND REGION. CONTINUED DRY CONDITIONS ARE EXPECTED THROUGH FRIDAY. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH AXIS EXTENDS FROM 36N65W TO 29N67W THAT SUPPORTS A 1018 MB LOW NEAR 35N60W. THE ASSOCIATED COLD FRONT EXTENDS SW FROM THE LOW CENTER TO 31N70W TO 30N76W BECOMING STATIONARY TO THE FLORIDA PENINSULA NEAR 30N81W. A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM THE COLD FRONT NEAR 32N64W SW TO 25N69W. MOST CONVECTION IS OCCURRING EAST OF THE UPPER LEVEL TROUGH AXIS WITH SCATTERED SHOWERS AND TSTMS N OF 27N BETWEEN 60W-66W. ISOLATED SHOWERS ARE OCCURRING ELSEWHERE WITHIN 60 NM EITHER SIDE OF THE FRONT W OF 66W. FARTHER EAST...ANOTHER UPPER LEVEL TROUGH AXIS IS NOTED FROM 29N57W TO 20N64W THAT SUPPORTS A SURFACE TROUGH ANALYZED FROM 20N61W TO 26N59W. ISOLATED SHOWERS ARE OCCURRING FROM 19N-27N BETWEEN 56W-63W. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED NEAR 31N45W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN