000 AXNT20 KNHC 121744 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE MAY 12 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. ...SPECIAL FEATURES... A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE ACROSS THE CENTRAL ATLC AND LOWER PRESSURE ACROSS NORTHWESTERN SOUTH AMERICA IS GENERATING NEAR GALE TO GALE FORCE WINDS WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. THESE CONDITIONS WILL PULSE DURING THE OVERNIGHT AND MORNING HOURS THROUGH WEDNESDAY NIGHT. SEE LATEST NWS HIGH SEAS FORECAST UNDER WMO/AWIPS HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N13W TO 06N18W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N18W TO 05N23W TO 04N37W TO 03N51W. WIDELY SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 08N BETWEEN THE PRIME MERIDIAN AND 16W. ...DISCUSSION... GULF OF MEXICO... A MID-LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER EASTERN TEXAS WITH A PORTION OF THE MID-LEVEL ENERGY STRETCHING OVER THE FAR NW GULF WATERS. THE TROUGHING SUPPORTS A STATIONARY FRONT EXTENDING FROM THE TEXAS/LOUISIANA BORDER NEAR 31N94W TO THE RIO GRANDE RIVER NEAR 28N100W. A PRE-FRONTAL SURFACE TROUGH IS ANALYZED FROM THE LOUISIANA COAST NEAR 29N92W SW TO THE TEXAS COAST NEAR 27N97W. GIVEN AN OVERALL DIFFLUENT ENVIRONMENT ALOFT ACROSS THE WESTERN GULF AND MOIST CONVERGENT SOUTHEASTERLY SURFACE FLOW TO THE SOUTH OF THE FRONTAL BOUNDARY...SCATTERED SHOWERS AND TSTMS ARE OCCURRING WEST OF A LINE FROM 30N91W TO 20N97W...INCLUDING INLAND PORTIONS OF SE TEXAS AND SW LOUISIANA. OTHERWISE...AN RELATIVELY AMPLIFIED UPPER LEVEL RIDGE INFLUENCES THE EASTERN GULF WITH AXIS EXTENDING FROM OVER THE NORTHERN YUCATAN PENINSULA NEAR 20N90W N- NE TO OVER NORTHERN GEORGIA AND ALABAMA. WITH NORTHERLY FLOW ALOFT ON THE EASTERN PERIPHERY OF THE UPPER LEVEL RIDGING... OVERALL STABLE CONDITIONS RESULT AT THE SURFACE IN ADDITION TO A 1022 MB HIGH CENTERED NEAR 30N86W. GENTLE TO MODERATE E-SE WINDS PREVAIL ON THE SOUTHERN PERIPHERY OF THE HIGH WITH MOSTLY CLEAR SKIES NOTED ON SATELLITE IMAGERY E OF 90W. THE SURFACE RIDGE IS EXPECTED TO PREVAIL THROUGH SATURDAY. CARIBBEAN SEA... ASIDE FROM NEAR GALE TO GALE FORCE CONDITIONS OCCURRING ACROSS PORTIONS OF THE SW CARIBBEAN OFF THE COAST OF COLOMBIA THE NEXT FEW DAYS...BROAD UPPER LEVEL TROUGHING IS NOTED ON WATER VAPOR IMAGERY OVER THE WESTERN CARIBBEAN WITH SOUTHWESTERLY FLOW PREVAILING TO THE EAST OF 75W OVER THE EASTERN CARIBBEAN. HIGH LEVEL CLOUDINESS CONTINUES TO STREAM FROM THE SW CARIBBEAN NORTHEASTWARD OVER THE NE CARIBBEAN INCLUDING HISPANIOLA AND PUERTO RICO. OTHERWISE...THE STRONG TRADE WINDS ARE THE MAIN IMPACT GENERATED BY A STRENGTHENED PRESSURE GRADIENT BETWEEN A STRONG 1030 MB SUBTROPICAL HIGH CENTERED NEAR 32N56W AND LOWER PRESSURE ACROSS NORTHWESTERN SOUTH AMERICA ANCHORED BY A 1007 MB LOW CENTERED NEAR 09N76W. THE PRESSURE GRADIENT IS FORECAST TO RELAX SOMEWHAT BY FRIDAY AS FRONTAL TROUGHING MOVES ACROSS THE SW NORTH ATLC REGION TO THE N-NE OF THE BASIN. ...HISPANIOLA... CURRENTLY...RELATIVELY CLEAR SKIES PREVAIL ACROSS THE ISLAND THIS AFTERNOON...HOWEVER A BROAD UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE WESTERN CARIBBEAN PROVIDING FOR DIFFLUENT CONDITIONS ALOFT. ISOLATED SHOWERS ARE POSSIBLE DURING THE AFTERNOON AND EVENING HOURS GIVEN PEAK DAYTIME HEATING AND INSTABILITY. ATLANTIC OCEAN... AN UPPER LOW IS CENTERED NORTHEAST OF THE BAHAMAS NEAR 29N69W THAT ANCHORS BROAD UPPER LEVEL TROUGHING WITH AXIS EXTENDING FROM THE LOW CENTER SW TO A BASE OVER EASTERN CUBA. THE TROUGHING SUPPORTS A FEW ISOLATED AREAS OF CONVECTION...ONE WITH SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING FROM 22N-25N BETWEEN 78W-80W AND ISOLATED SHOWERS FROM 22N-28N BETWEEN 62W- 73W. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1030 MB HIGH CENTERED NEAR 32N56W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN