000 AXNT20 KNHC 072339 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON APR 07 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. ...SPECIAL FEATURES... A COLD FRONT IS ANALYZED FROM THE FAR WESTERN FLORIDA PANHANDLE NEAR 31N88W SW TO 23N95W TO 19N95W. NORTHERLY WINDS CONTINUE FUNNELING SOUTHWARD ALONG THE MEXICO COAST AND ARE EXPECTED TO STRENGTHEN TO GALE FORCE BY 08/1800 UTC ACROSS THE SW GULF S OF 20N W OF 95W. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N13W TO 02N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 02N16W TO THE EQUATOR NEAR 18W. ISOLATED MODERATE CONVECTION IS FROM 01N-06N BETWEEN 07W-21W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL TROUGH WITH EMBEDDED MID-LEVEL SHORTWAVE ENERGY IS NOTED ON WATER VAPOR IMAGERY OVER THE CENTRAL CONUS THIS EVENING. THE STRONGEST MID-LEVEL ENERGY IS CURRENTLY CENTERED OVER THE OHIO RIVER VALLEY THIS EVENING AND SUPPORTS A PARTIALLY OCCLUDED 997 MB LOW CENTERED ACROSS SOUTHERN INDIANA WITH A COLD FRONT EXTENDING INTO THE GULF BASIN NEAR THE EXTREME WESTERN FLORIDA PANHANDLE NEAR 31N88W. THE FRONT CONTINUES SW TO 23N95W THEN SOUTHWARD TO THE MEXICO COAST NEAR 19N95W. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 75 NM EITHER SIDE OF THE COLD FRONT N OF 23N. HOWEVER...THE MORE INTENSE PRECIPITATION IS NOTED EAST OF THE COLD FRONT IN ASSOCIATION WITH A SQUALL LINE EXTENDING FROM 30N84W TO 28N86W. SCATTERED SHOWERS AND TSTMS SURROUND THE SQUALL LINE AXIS N OF 28N BETWEEN 82W-86W...AND FROM 26N-28N BETWEEN 85W-90W. THIS CONVECTION ACTIVITY IS LIKELY ENHANCED BY MAXIMUM MIDDLE TO UPPER LEVEL DIFFLUENCE ACROSS THE NORTHEASTERN GULF AS SOUTHWESTERLY FLOW ALOFT CONTINUES TO ADVECT EASTERN PACIFIC MOISTURE OVER CENTRAL MEXICO AND THE GULF OF MEXICO THIS EVENING. OTHERWISE...WEAK RIDGING IS FOUND ACROSS THE SE GULF AND NW GULF ON EITHER SIDE OF THE FRONTAL ZONE. LOOKING AHEAD... AS THE COLD FRONT SWEEPS EASTWARD...STRONG SURFACE RIDGING IS FORECAST TO BUILD IN ACROSS TEXAS AND THE WESTERN GULF THROUGH EARLY WEDNESDAY. CARIBBEAN SEA... A MIDDLE TO UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE WESTERN CARIBBEAN NEAR 15N80W WITH WATER VAPOR IMAGERY INDICATING THE AIRMASS INFLUENCING THE BASIN THIS EVENING IS VERY DRY AND STABLE. THIS STABILITY ALOFT CONTINUES TO IMPACT THE SURFACE CONDITIONS WITH MOSTLY FAIR SKIES AND AN OVERALL LACK OF ANY SIGNIFICANT CONVECTION THIS EVENING. THE MOST IMPORTANT MARINE IMPACT HOWEVER REMAINS RATHER STRONG TRADE WINDS AS THE PRESSURE GRADIENT BETWEEN A SURFACE RIDGE ACROSS THE SW NORTH ATLC TO THE NORTH AND LOWER PRESSURE TO THE SOUTH ACROSS NORTHERN SOUTH AMERICA IS GENERATING E-SE WINDS IN THE RANGE OF 15 TO 25 KT WITH THE STRONGEST WINDS NOTED BETWEEN 65W-78W...AND A SMALL AREA S OF 20N W OF 84W...WHICH INCLUDES THE GULF OF HONDURAS. OTHERWISE...CONDITIONS ARE EXPECTED TO MODIFY VERY LITTLE OVER THE NEXT 24 TO 36 HOURS UNTIL A COLD FRONT REACHES THE YUCATAN CHANNEL BY LATE TUESDAY INTO EARLY WEDNESDAY INTRODUCING STRONG NORTHERLY WINDS TO THE NW CARIBBEAN WEDNESDAY AND THURSDAY. ...HISPANIOLA... CURRENTLY CONDITIONS ACROSS THE ISLAND THIS EVENING REMAIN RATHER TRANQUIL AND QUIET AS MIDDLE TO UPPER LEVEL DRY AND STABLE NORTHERLY FLOW PREVAILS. THIS OVERALL SYNOPTIC PATTERN IS EXPECTED TO CHANGE VERY LITTLE THROUGH LATE WEDNESDAY. THEREAFTER...AN APPROACHING FRONTAL BOUNDARY MOVING ACROSS CUBA AND THE SW NORTH ATLC TO THE NORTH WILL BEGIN TO IMPACT HISPANIOLA WITH AN INCREASE IN MOISTURE...CLOUDINESS...AND A HIGHER PROBABILITY OF PRECIPITATION DURING THE DAY ON THURSDAY. THE FRONT WILL LIKELY STALL NW OF THE ISLAND PROVIDING CONTINUED ISOLATED SHOWERS ON FRIDAY. ATLANTIC OCEAN... MUCH OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF MIDDLE TO UPPER LEVEL RIDGING ALOFT WITH THE RIDGE AXIS REACHING 30N ALONG 76W. PLENTY OF MIDDLE TO UPPER LEVEL MOISTURE AND CLOUDINESS CONTINUES TO PRECEDE AN APPROACHING UPPER LEVEL TROUGH CURRENTLY ACROSS THE CENTRAL CONUS. PRE-FRONTAL WIDESPREAD SHOWERS AND ISOLATED TSTMS ARE OCCURRING ALONG THE FLORIDA PENINSULA COAST FROM 27N-30N W OF 80W AND N OF 30N W OF 79W. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS INFLUENCED BY A WEAKENING SURFACE RIDGE BETWEEN 53W-78W. FARTHER EAST...A MIDDLE TO UPPER LEVEL LOW IS CENTERED SW OF THE IBERIAN PENINSULA NEAR 33N24W THAT SUPPORTS A PARTIALLY OCCLUDED 1009 MB LOW CENTERED NEAR 32N25W. THE OCCLUSION WRAPS AROUND THE SURFACE LOW TO A COLD FRONT EXTENDING FROM 34N23W TO 30N22W TO 25N25W TO 21N40W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE FRONT. THE TAIL END OF THE COLD FRONT BECOMES STATIONARY FROM 21N40W INTO A WEAK 1019 MB LOW CENTERED NEAR 24N50W. THIS VERY WEAK LOW IS MARGINALLY SUPPORTED ALOFT BY A SHORTWAVE TROUGH NOTED ON WATER VAPOR IMAGERY IN THE VICINITY OF 29N49W THAT CONTINUES TO MOVE S-SE. ISOLATED SHOWERS ARE OCCURRING FROM 21N- 27N BETWEEN 44W-53W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN