000 AXNT20 KNHC 220000 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EST MON APR 21 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 2345 UTC. ...THE ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SECTIONS OF SENEGAL NEAR 12N16W TO 4N25W. THE ITCZ CONTINUES FROM 4N25W THROUGH 1N30W...CROSSING THE EQUATOR ALONG 32W...TO 2S45W NEAR THE COAST OF BRAZIL. NO SIGNIFICANT CONVECTION NOTED IN ASSOCIATION WITH THE MONSOON TROUGH OR ITCZ. A SURFACE TROUGH EXTENDS FROM 4N2W THROUGH 3N10W TO 4N21W. NUMEROUS STRONG CONVECTION WAS NOTED WITHIN 60 NM EITHER SIDE OF THE TROUGH BETWEEN 13W-18W. SCATTERED MODERATE TO ISOLATED STRONG ELSEWHERE NORTH OF THE EQUATOR TO 5N BETWEEN 8W-18W. ...DISCUSSION... ...THE GULF OF MEXICO... A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER AND TROUGH OVER THE RED RIVER VALLEY AND TEXAS ARE MOVING EASTWARD WITH A WEAK SHORTWAVE TROUGH SWEEPING ACROSS THE NW GULF IN ADVANCE OF THE MAIN TROUGH. BROAD UPPER LEVEL ANTICYCLONIC WIND FLOW SPANS THE REMAINDER OF THE GULF OF MEXICO WITH UPPER LEVEL MOISTURE SWEEPING ACROSS MOST OF THE GULF N OF 23N. AT THE SURFACE...A 1021 MB HIGH PRESSURE AREA CENTERED JUST SE OF MOBILE ALABAMA DOMINATES THE GULF WITH GENERALLY LIGHT WINDS NOTED. SOUTHERLY RETURN FLOW WAS INCREASING OVER THE FAR WESTERN GULF WITH SURFACE WINDS MIXING OUT THE LOW CLOUDS NOTED OVER THE AREA EARLIER IN THE DAY. PATCHES OF STRATOCUMULUS CLOUDS WERE NOTED OVER THE GULF E OF 90W. ...THE CARIBBEAN SEA... AN UPPER LEVEL RIDGE EXTENDS FROM NORTHWESTERN VENEZUELA...NORTHERN COLOMBIA AND THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA...INTO NICARAGUA. UPPER LEVEL WESTERLY WINDS EXTEND FROM THE SOUTHERN GULF OF MEXICO...THE YUCATAN PENINSULA AND THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA. THE WESTERLY WINDS EVENTUALLY MERGE WITH THE ANTICYCLONIC WIND FLOW FROM THE RIDGE...AND CONTINUES ACROSS THE CARIBBEAN SEA EASTWARD INTO THE TROPICAL ATLANTIC. BROKEN TO OVERCAST LOW AND MIDDLE LEVEL CLOUDS AND POSSIBLE RAINSHOWERS WERE NOTED TO THE NORTH OF 14N AND EAST OF 68W...AND NORTH OF 16N WEST OF 70W...IN SURFACE TRADEWIND FLOW. SCATTEROMETER DATA INDICATED MODERATE TRADE WINDS EAST OF 70W AND WITHIN 120 NM OF THE COAST OF COLOMBIA WITH LIGHT TRADES ELSEWHERE. MODERATE NORTHERLY WINDS WERE NOTED ALONG THE IMMEDIATE COAST OF YUCATAN AND BELIZE BEHIND A WEAKENING COLD FRONT EXTENDING FROM THE COAST OF CUBA NEAR 20N77.5W TO 19N84W. ...HISPANIOLA... GENERALLY ZONAL WESTERLY WINDS PREVAIL OVER HISPANIOLA ON THE NORTHERN PERIPHERY OF A FLAT RIDGE DOMINATING THE CARIBBEAN SEA. THE PROXIMITY OF A COLD FRONT EXTENDING FROM EXTREME EASTERN CUBA ACROSS THE FAR NW CARIBBEAN WAS PROVIDING ENOUGH FORCING FOR LOCALLY STRONG THUNDERSTORMS TO DEVELOP OVER THE INTERIOR OF HISPANIOLA NEAR THE BORDER OF HAITI AND THE DOMINICAN REPUBLIC. LAST LOW LIGHT VISIBLE IMAGERY INDICATED SOME OVERSHOOTING TOPS. THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAIN OVER THE NEXT FEW HOURS IN THE AREA. THE GFS MODEL FORECAST FOR 250 MB AND 500 MB SHOWS NORTHWEST TO WEST WIND FLOW ACROSS HISPANIOLA. THE GFS MODEL FORECAST FOR 700 MB SHOWS THAT AN ANTICYCLONIC CIRCULATION CENTER WILL BE OVER THE AREA. ...THE ATLANTIC OCEAN... MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTER NEAR 34N69W WAS NOW MOVING EASTWARD AND BECOMING KICKED OUT BY AN UPSTREAM TROUGH OVER THE EAST-CENTRAL U.S. ASSOCIATED TROUGHING COVERS THE SUBTROPICAL ATLANTIC N OF 20N W OF 62W. STRONG UPPER LEVEL SUBSIDENCE WAS WRAPPING INTO THE WEST SIDE OF THE TROUGH N OF 25N TO 68W. THIS TROUGH WAS SUPPORTING A COLD FRONT WHICH PASSED THROUGH 32N68W TO 25N70W...TO EXTREME EASTERN CUBA NEAR 21N75W. A DISSIPATING COLD FRONT CONTINUED INTO THE NW CARIBBEAN. A POST-FRONTAL SURFACE TROUGH EXTENDED THROUGH 32N71W TO THE EXTREME NE BAHAMAS. SCATTERED MODERATE TO STRONG THUNDERSTORMS WERE INDICATED WITHIN 180 NM E OF THE COLD FRONT FROM THE SE BAHAMAS TO 29N. A SHEARING MID TO UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION CENTER NEAR 25N30W THROUGH 21N40W TO A BASE NEAR 13N55W. STRONG DEEP LAYERED SUBSIDENCE WAS NOTED ALONG AND TO THE WEST OF THE UPPER LEVEL TROUGH AXIS... GENERALLY OVER THE TROPICAL ATLANTIC FROM 10N-23N WEST OF 45W...AND FROM 20N-25N BETWEEN 30W AND 40W. AT THE SURFACE...A 1022 MB HIGH PRESSURE CENTER NEAR 28N47W DOMINATED THE REMAINDER OF THE BASIN WITH ANTICYCLONIC WIND FLOW COVERING THE ATLANTIC OCEAN AND THE CARIBBEAN SEA TO THE NORTH OF 10N BETWEEN AFRICA AND 62W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB