000 AXNT20 KNHC 160535 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SAT APR 16 2011 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION 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 0530 UTC. ...THE ITCZ... ITCZ AXIS EXTENDS FROM THE SOUTHERN COAST OF SIERRA LEONE NEAR 7N12W...CONTINUING SW ALONG 3N20W 1N30W INTO BRAZIL NEAR 3S40W. NUMEROUS STRONG CONVECTION IS MOVING ACROSS LIBERIA AND OFFSHORE FROM 1N-7N BETWEEN 7W-20W. A BROAD AREA OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 8S-5N BETWEEN 20W-32W. A SURFACE TROUGH IS EMBEDDED WITHIN THIS AREA FROM EQ24W TO 5S23W. ANOTHER SURFACE TROUGH IS EMBEDDED IN THE ITCZ ANALYZED FROM 3N37W TO 2S37W SUPPORTING SCATTERED MODERATE CONVECTION NEAR THE AXIS. ...DISCUSSION... THE GULF OF MEXICO... THE MAJORITY OF THE GULF OF MEXICO IS EXPERIENCING FAIR WEATHER CONDITIONS UNDER THE INFLUENCE OF DRY AIR ALOFT ACROSS MOST OF THE AREA EXCEPT THE SW BASIN. HOWEVER...A DEEP LAYER TROUGH MOVES ACROSS THE CENTRAL/EASTERN CONUS SUPPORTING A VIGOROUS DEEP LOW PRESSURE SYSTEM. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS MOVING ACROSS THE NW BASIN ANALYZED FROM THE EASTERN COAST OF LOUISIANA NEAR 30N90W TO TAMPICO MEXICO NEAR 22N98W. WHILE SEVERE WEATHER IS ASSOCIATED WITH THE FRONTAL BOUNDARY ACROSS THE SE UNITED STATES...IT BECOMES MOSTLY DRY UPON ENTERING THE GULF REGION. ONLY A WEAK CLOUD BAND AND WIND SHIFT DEFINE THE FRONT OVER THE GULF WATERS. SURFACE OBS INDICATE 20-25 KT SLY WINDS AHEAD OF THE FRONT. NNW 10-15 KT ARE BEHIND THE FRONT. A SURFACE TROUGH IS S OF THE COLD FRONT ANALYZED OVER THE BAY OF CAMPECHE FROM 23N95W TO 18N94W. OTHER THAN A SE TO NE WIND SHIFT...THIS TROUGH IS NOT PRODUCING ANY CONVECTION. EXPECT THE COLD FRONT TO CONTINUE TO PUSH ESE ACROSS THE GULF OF MEXICO WITH POSSIBLE ISOLATED SHOWERS ALONG THE BOUNDARY. THE CARIBBEAN SEA... MAINLY DRY AIR ALOFT AND STRONG AND SUBSIDENCE IS ACROSS THE CARIBBEAN SEA THIS EVENING...PROVIDING MOSTLY FAIR CONDITIONS ACROSS THE BASIN. MARINE OBS INDICATE MODERATE TO FRESH TRADE WINDS ACROSS THE AREA. STRONGER TRADES ARE TURNING ACROSS THE COAST OF COLOMBIA...AROUND THE CLIMATOLOGICAL 1008 MB LOW NEAR 10N75W. THIS FEATURE IS ENHANCING SCATTERED SHOWERS OVER THE COAST OF PANAMA AND COLOMBIA BETWEEN 74W-78W. WEAK ISOLATED SHOWERS ARE NOTED ACROSS THE NRN ISLANDS OF CUBA AND HISPANIOLA. SIMILAR ACTIVITY IS OVER THE LESSER ANTILLES S OF DOMINICA. FAIR WEATHER IS EXPECTED TO REMAIN ACROSS THE REST OF THE BASIN OVER THE NEXT 24 HOURS. THE ATLANTIC OCEAN... A BROAD UPPER LEVEL TROUGH IS OVER THE NW ATLC SUPPORTING A SURFACE TROUGH ALONG 32N60W TO 26N59W. SCATTERED WEAK SHOWERS ARE E OF THE TROUGH UP TO 70 NM. AN UPPER LEVEL LONGWAVE PUSHES OUT OF THE EASTERN CARIBBEAN ACROSS THE LEEWARD ISLANDS SUPPORTING A SURFACE TROUGH EXTENDING 22N58W TO 17N61W. DIFFLUENCE FLOW ALOFT AROUND THE E SIDE OF THE UPPER LONGWAVE IS SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WITHIN 130 NM E OF THE TROUGH AXIS. THIS SYSTEM IS EXPECTED TO DRIFT E OVER THE NEXT 24 HOURS. COMPUTER MODEL SUGGESTS A LOW COULD DEVELOP WITHIN THE TROUGH AXIS DURING THE FORECAST PERIOD. FARTHER E...A DEEP LAYERED 1004 MB LOW PRESSURE SYSTEM SPINS NEAR 30N30W. AN OCCLUDED FRONT EXTENDS AROUND THE WESTERN AND NORTHERN SEMI-CIRCLE OF THE LOW AND ENTERS THE AREA AS A COLD FRONT EXTENDING FROM 32N24W TO 27N25 TO 24N27W. SCATTERED WEAK SHOWERS ARE WITHIN 30 NM EITHER SIDE OF THE OCCLUDED FRONT...AND WITHIN 30 NM EITHER SIDE OF THE COLD FRONT. THIS LOW PRESSURE SYSTEM IS EXPECTED TO DRIFT SSE OVER THE NEXT 24 HOURS PRODUCING SCATTERED WEAK TO ISOLATED MODERATE CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA