000 AXNT20 KNHC 192347 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE MAY 19 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLANTIC NEAR 11N16W CONTINUING TO 05N23W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 03N37W TO THE NORTHERN COAST OF BRAZIL NEAR 01N50W. SCATTERED MODERATE CONVECTION IS FROM 02N TO 09N E OF 23W AND WITHIN 120 NM EITHER SIDE OF THE ITCZ AXIS. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE EXTENDS FROM THE NORTHERN PLAINS SE TO THE CENTRAL U.S. CONTINUING ACROSS THE NORTHERN HALF OF THE GULF WHERE IS ANCHORED BY A 1018 MB HIGH NEAR 27N85W. UPPER LEVEL TROUGHING IS ACROSS THE GULF E OF 90W WITH AN UPPER LEVEL RIDGING BUILDING IN ACROSS THE GULF W OF 90W. THE TROUGHING ALOFT ALONG WITH MODERATE LOW-LEVEL MOISTURE SUPPORT SCATTERED SHOWERS AND TSTMS OVER NORTHERN AND CENTRAL FLORIDA. MAINLY FAIR WEATHER PREVAILS UNDER THE RIDGING WITH LIGHT TO MODERATE ANTICYCLONIC FLOW...EXCEPT LIGHT AND VARIABLE IN THE NE GULF NEAR THE HIGH CENTER. THERMAL TROUGHING DEVELOPED OVER THE YUCATAN PENINSULA THIS EVENING...WHICH IS FORECAST TO MOVE OFFSHORE INTO THE SW GULF INTO WED MORNING...AND YET AGAIN WED EVENING INTO THU MORNING. AS A RESULT WINDS WILL INCREASE TO FRESH OR EVEN LOCALLY STRONG NEAR THE NW YUCATAN PENINSULA WITH SEAS BUILDING TO UP TO 6 FT AS A RESULT. A COLD FRONT IS EXPECTED TO DIP INTO THE NE GULF BY FRIDAY MORNING. CARIBBEAN SEA... MIDDLE TO UPPER LEVEL SOUTHWESTERLY TO WESTERLY FLOW PREVAILS WHICH IS ADVECTING TROPICAL MOISTURE FROM THE NE PACIFIC OCEAN AND NORTHERN SOUTH AMERICA. A MIDDLE TO UPPER LEVEL TROUGH IS ACROSS THE NW CARIBBEAN WITH DRY AND STABLE AIR INDICATED BY WATER VAPOR AND SSMI TOTAL PRECIPITABLE WATER IMAGERY. A LOCALIZED TIGHT PRES GRADIENT CONTINUES IN THE S CENTRAL CARIBBEAN BETWEEN LOW PRES OVER NW COLOMBIA AND ATLC RIDGING N- NE OF THE AREA. THIS IS SUPPORTING A MODERATE TO FRESH BREEZE NEAR THE NW COAST OF COLOMBIA AND SEAS UP TO 8 FT. THESE WINDS WILL CONTINUE TO PULSE NEAR THE COAST OF COLOMBIA THROUGH EARLY WED BEFORE DIMINISHING AS THE PRES GRADIENT RELAXES SLIGHTLY. OTHERWISE GENTLE TRADES AND 4-6 FT SEAS PREVAIL S OF 17N...WITH GENTLE TRADES AND 2-4 FT SEAS N OF 17N. EXPECT SIMILAR WEATHER CONDITIONS THROUGH THE NEXT 48 HOURS. ...HISPANIOLA... LINGERING MOISTURE ASSOCIATED WITH A WEAKENING STATIONARY FRONT WITH TAIL CURRENTLY REACHING NE COASTAL WATERS OF THE ISLAND CONTINUE TO SUPPORT ISOLATED SHOWERS AND TSTMS. CONVECTIVE ACTIVITY THROUGH THE NEXT 48 HOURS WILL ALSO BE SUPPORTED EACH AFTERNOON AND EVENING DUE TO OROGRAPHIC LIFTING AND DAYTIME HEATING. ATLANTIC OCEAN... A STATIONARY FRONT EXTENDS FROM 31N47W SW TO 25N54W THEN IS DISSIPATING AS IT CONTINUES TOWARD THE NE COASTAL WATERS OF HISPANIOLA. SCATTERED SHOWERS AND TSTMS ARE OCCURRING N OF 24N WITHIN 60-90 NM EITHER SIDE OF THE BOUNDARY. THE SW PORTION OF THIS BOUNDARY WILL COMPLETELY DISSIPATE LATER TONIGHT. WEST OF THIS BOUNDARY...A COLD FRONT CONTINUES TO DROP S INTO THE AREA EXTENDING FROM A 1007 MB LOW PRES NEAR 33N57W TO 30N57W SW TO 27N63W TO 30N69W. SCATTERED SHOWERS AND TSTMS ARE AHEAD OF THE FRONT N OF 27N BETWEEN 51W AND 59W. THIS FRONT WILL GRADUALLY WEAKEN THROUGH THE NEXT 24-48 HOURS AS IT CONTINUES TO MOVE TO THE S-SE...EVENTUALLY STALLING ALONG 25N W OF 60W BY THU. A WEAK SURFACE TROUGH IS OVER WEST COASTAL WATERS OF THE NORTHERN AND CENTRAL BAHAMAS WITH ISOLATED SHOWERS AND TSTMS. THIS TROUGH IS FORECAST TO DRIFT TO THE W AND DISSIPATE LATER TONIGHT. OTHERWISE 1019 MB SURFACE HIGH PRES IS LOCATED NEAR 27N73W WITH A RIDGE AXIS EXTENDING TO THE W-NW TO NEAR JACKSONVILLE FLORIDA. LIGHT AND VARIABLE WINDS ARE NEAR THE RIDGE AXIS WITH MODERATE ANTICYCLONIC FLOW ELSEWHERE. THE HIGH AND RIDGING WILL SHIFT TO THE SE DURING THE NEXT 24-48 HOURS AS A WEAK COLD FRONT APPROACHES THE NW CORNER OF THE SW N ATLC MOVING OFF THE SE GEORGIA COAST BY EARLY FRIDAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ RAMOS