000 AXNT20 KNHC 240518 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SAT APR 24 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0415 UTC... ...ITCZ... THE ITCZ IS ANALYZED ALONG 9N12W 4N24W 3N40W 3N52W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 1N-8N BETWEEN 9W-23W AND FROM 1N-5N BETWEEN 26W-37W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER TROUGH COVERS THE CENTRAL PLAINS STATES WITH A SHORTWAVE UPPER TROUGH MOVING ACROSS THE LOWER MISSISSIPPI VALLEY. THE ASSOCIATED FRONTAL SYSTEM REMAINS INLAND OVER THE US WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE NE GULF WATERS N OF 28N E OF 87W TO OVER FLORIDA. A BROAD UPPER RIDGE AXIS EXTENDS FROM THE E PACIFIC REGION ACROSS S MEXICO THROUGH THE BAY OF CAMPECHE NEAR 19N93W TO THE N GULF COAST NEAR 30N89W DOMINATING ALL OF THE GULF WATERS. THIS UPPER FLOW IS DRAWING TROPICAL MOISTURE ACROSS MEXICO TO OVER THE GULF GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 150 NM OF LINE FROM OVER MEXICO NEAR TAMPICO TO 28N90W. CARIBBEAN SEA... THE UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE NW CARIBBEAN WITH A SECOND UPPER RIDGE ANCHORED OVER TROPICAL ATLC COVERS THE REMAINDER OF THE CARIBBEAN INDUCING A WEAK UPPER TROUGH THAT EXTENDS ALONG A LINE FROM CUBA NEAR 21N78W TO THE TIP OF NICARAGUA/HONDURAS. UPPER LEVEL MOISTURE FROM THE GULF OF MEXICO COVERS THE FAR NW CARIBBEAN AND SIMILAR UPPER LEVEL MOISTURE COVERS THE SW CARIBBEAN GIVING THOSE AREAS HIGH CLOUDS AND LEAVING THE CENTRAL CARIBBEAN FAIRLY DRY. THE INCREASE PRESSURE GRADIENT BETWEEN THE LOW PRESSURE OVER THE THE TROPICS AND A SURFACE RIDGE OVER THE W ATLC IS GIVING THE CARIBBEAN INCREASING TRADE WINDS ACROSS THE AREA AND LOW LEVEL FAST MOVING ISOLATED SHOWERS MAINLY N OF A LINE FROM THE VIRGIN ISLANDS NEAR 18N64W ALONG 15N70W TO 16N75W INCLUDING PUERTO RICO AND HISPANIOLA. ATLANTIC OCEAN... A SURFACE RIDGE COVERS THE FAR W ATLC ANCHORED BY A 1019 MB HIGH NE OF THE BAHAMAS NEAR 28N76W. A BROAD LOW AMPLITUDE UPPER TROUGH COVERS THE NW ATLC MOSTLY N OF 30N SUPPORTING A COLD FRONT THAT ENTERS THE CENTRAL ATLC NEAR 32N49W EXTENDING SW TO 25N61W WITH POSSIBLE ISOLATED SHOWERS WITHIN 45 NM E OF THE FRONT. A WEAKER UPPER TROUGH IS OVER THE E ATLC SUPPORTING A WEAKENING COLD FRONT ENTERING THE REGION NEAR 32N23W EXTENDING SW ALONG 26N31W TO 24N42W. THIS FRONT BISECTS A SURFACE RIDGE WITH A 1019 MB HIGH BEHIND THE FRONT NEAR 27N37W AND A 1018 MB HIGH SE OF THE FRONT NEAR 23N29W. THE UPPER RIDGE ANCHORED OVER THE TROPICAL ATLC NEAR 6N43W COVERS THE CARIBBEAN AS WELL AS THE E AND CENTRAL ATLC AND PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED CLUSTERS OF SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 20N-32N BETWEEN 40W-51W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALLACE