000 AXNT20 KNHC 041711 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE MAY 04 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1645 UTC... ...ITCZ... ITCZ AXIS IS CENTERED FROM NIGERIA NEAR 4N8E ALONG 4N AND THE PRIME MERIDIAN 2N10W 2N20W 4N30W 5N40W 3N53W. AN EMBEDDED SURFACE TROUGH IS FROM 5N-10N ALONG 26W. SCATTERED MODERATE/STRONG CONVECTION IS FROM EQ-4N BETWEEN 1W-6W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM EQ-2N BETWEEN 7W-9W...FROM 2N-5N BETWEEN 13W-15W...5N-10N BETWEEN 32W-43W...AND OFF THE NE SOUTH AMERICA COAST FROM EQ-7N BETWEEN 48W-56W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...A COLD FRONT EXTENDS DOWN THE SE UNITED STATES ACROSS THE FLORIDA PANHANDLE CROSSING TALLAHASSEE INTO THE GULF OF MEXICO TO A 1013 MB LOW NEAR 29N89W. A STATIONARY FRONT CONTINUES FROM THE LOW CENTER TO NEAR 26N91W. A SURFACE TROUGH IS S OF THE FRONT ALONG 26N89W 23N91W 19N91W. SURFACE CONVERGENCE NEAR THE COLD FRONT COMBINED WITH A NARROW SWATH OF UPPER LEVEL MOISTURE IN SWLY FLOW ALOFT SUPPORT A LINE OF HEAVY SHOWERS/THUNDERSTORMS E OF THE COLD FRONT WITHIN 60 NM AS INDICATED BY RADAR IMAGERY. POSSIBLE ISOLATED SHOWERS ARE AHEAD OF THE STATIONARY BOUNDARY...AND WITHIN 60 NM EITHER SIDE OF THE SURFACE TROUGH. SIGNIFICANT DRY AIR ALOFT IS TO EITHER SIDE OF THE SWATH OF MOISTURE ASSOCIATED WITH THE FRONT KEEPING SURFACE CONDITIONS FAIR WITH MOSTLY CLEAR SKIES ACROSS THE REMAINDER OF THE BASIN. SURFACE RIDGING COVERS THE FAR E GULF EXTENDING FROM HIGH PRESSURE IN THE W ATLC. SURFACE RIDGING IS ALSO W OF THE FRONT EXTENDING FROM HIGH PRESSURE ACROSS MEXICO AND SE TEXAS. EXPECT THE COLD FRONT TO CONTINUE TO MAKE ITS WAY ACROSS NRN FLORIDA WHILE THE BOUNDARIES TO THE S LAG BEHIND. CARIBBEAN SEA... CONDITIONS REMAIN FAIR ACROSS THE NW CARIBBEAN DUE TO THE INFLUENCE OF SIGNIFICANT DRY AIR ALOFT EXTENDING FROM THE SE GULF OF MEXICO. HOWEVER...A MID-LEVEL LOW NEAR 16N79W IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS FROM 15N-18N BETWEEN 80W-83W. THIS MID-UPPER LEVEL TROUGH IS DRAWING MOISTURE FROM THE E PACIFIC ACROSS THE CENTRAL AND ERN CARIBBEAN ENHANCING ISOLATED SHOWERS IN THE ELY MODERATE TO FRESH TRADEWIND FLOW. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE SW CARIBBEAN S OF 12N DUE TO SURFACE CONVERGENCE NEAR THE E PACIFIC ITCZ WHICH CROSSES OVER CENTRAL AMERICA ALONG THE COSTA RICA/PANAMA BORDER AND CONTINUES EWD TO NRN COLOMBIA. ATLANTIC OCEAN... A SURFACE RIDGE DOMINATES THE W ATLC ANCHORED BY A 1023 MB HIGH NEAR 28N66W KEEPING MUCH OF THE W ATLC UNDER FAIR CONDITIONS. THE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE CENTERED NEAR 29N66W. ACROSS THE CENTRAL ATLC...AN UPPER LEVEL TROUGH SUPPORTS A FRONTAL SYSTEM CENTERED N OF THE DISCUSSION AREA. A STATIONARY FRONT ENTERS THE AREA NEAR 32N29W ALONG 28N32W 24N38W DISSIPATING TO NEAR 21N42W...AND CONTINUING AS A SHEAR LINE TO NEAR 16N59W. SCATTERED SHOWERS ARE WITHIN 45 NM E OF THE FRONT N OF 27N. ISOLATED SHOWERS ARE POSSIBLE ALONG THE REMAINDER OF THE FRONT AND SHEAR LINE. THE UPPER LEVEL TROUGH ASSOCIATED WITH THIS SYSTEM MAY ALSO BE ENHANCING THE CONVECTION ALONG THE WRN HALF OF THE ATLC ITCZ. FARTHER E...AN UPPER LEVEL RIDGE EXTENDING FROM THE CAPE VERDE ISLANDS TO THE CANARY ISLANDS SUPPORTS A SURFACE RIDGE CENTERED WELL N OF THE DISCUSSION AREA BY A 1036 MB HIGH NEAR 53N17W KEEPING THE E TROPICAL ATLC UNDER GENERALLY FAIR WEATHER. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON