000 AXNT20 KNHC 291800 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI APR 29 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...THE ITCZ... FROM THE NORTHERN LIBERIAN COAST NEAR 7N11W TO 3N20W TO THE EQUATOR AT 27W TO 2N33W...BECOMING INDISTINCT AT THE EQUATOR AND 38W. SCATTERED MODERATE TO STRONG THUNDERSTORMS WERE NOTED WITHIN 60-90 NM N OF THE AXIS BETWEEN 31W AND 36W. SCATTERED MODERATE ISOLATED STRONG THUNDERSTORMS WERE NOTED WITHIN 120 NM N OF THE AXIS BETWEEN 14W AND 17W...AND FROM 3N TO 6N BETWEEN 24W AND 30W. SCATTERED TO NUMEROUS STRONG THUNDERSTORMS WERE NOTED WITHIN 90 NM OF THE COAST OF SOUTHERN LIBERIA. ...DISCUSSION... THE GULF OF MEXICO... STRONG SUBSIDENCE PREVAILED AT THE UPPER LEVELS OVER THE GULF OF MEXICO IN AN AREA OF MODERATE UPPER LEVEL WESTERLY WINDS IN THE WAKE OF A DEPARTING TROUGH MOVING OFF THE SE U.S. COAST. A AS OF 1500 UTC A COLD FRONT EXTENDED FROM JUST N OF FORT PIERCE TO PORT CHARLOTTE IN THE STATE OF FLORIDA...THEN BECOMES A DISSIPATING STATIONARY FRONT NEAR 25N85W AND CONTINUES TO 22N94W. VISIBLE SATELLITE IMAGERY STILL DEPICTS A WELL DEFINED ROPE CLOUD WITH ISOLATED SHOWERS ASSOCIATED WITH THE FRONT INTO THE GULF. PATCHES OF LOW CLOUDS COVER THE SOUTHWEST GULF OF BAY OF CAMPECHE FROM 20N TO 25N WEST OF 90W TO THE EAST COAST OF MEXICO. THE LOW CLOUDS WERE STREAMING NORTHWARD AS SURFACE AND LOW LEVEL WINDS INCREASE OVER THE WESTERN GULF. VISIBLE SATELLITE IMAGERY ALSO INDICATED AREAS OF SMOKE AND HAZE OVER THE BAY OF CAMPECHE ORIGINATING FROM FIRES OVER THE YUCATAN PENINSULA. SURFACE OBSERVATIONS INDICATED VISIBILITIES OF 3 NM IN SMOKE AND HAZE. SKIES OVER THE NORTHERN THIRD OF THE GULF OF MEXICO WERE CLEAR WITH LIGHT TO MODERATE EASTERLY WINDS ALONG THE SOUTHERN PERIPHERY OF HIGH PRESSURE LOCATED OVER LOUISIANA. THE CARIBBEAN SEA... A BROAD BELT OF UPPER LEVEL WESTERLY WINDS IS SWEEPING ACROSS THE CARIBBEAN WITH THE FLOW BECOMING MORE CYCLONIC OVER HISPANIOLA AND ALONG 70W IN ASSOCIATION WITH THE SOUTHWESTERN END OF AN UPPER LEVEL TROUGH OVER THE SOUTHWEST NORTH ATLANTIC. AT THE SURFACE...BRISK EASTERLY TRADES CONTINUE OVER MOST OF THE BASIN WITH A 1342 UTC ASCAT PASS INDICATING STEADY 20 KT WINDS OVER THE EASTERN CARIBBEAN N OF 14N. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WERE OCCURRING OVER THE WINDWARD ISLANDS BETWEEN ST. LUCIA AND GUADELOUPE AND EXTENDED WESTWARD WITHIN 45 NM EITHER SIDE OF A LINE THROUGH 15N64W TO 16N70W. SCATTERED SHOWERS AND THUNDERSTORMS WERE ALSO OCCURRING IN THE GULF OF HONDURAS JUST WEST OF ROATAN AND EXTENDING OVER HONDURAS. SCATTERED TRADE WIND CUMULUS WERE INDICATED ELSEWHERE ACROSS THE CARIBBEAN SEA. THE ATLANTIC OCEAN... A COMPLEX UPPER LEVEL CYCLONIC CIRCULATION CENTER WITH A MEAN CENTER NEAR 27N58W IS DRIFTING WESTWARD WITH THE ASSOCIATED CYCLONIC FLOW COVERING THE AREA TO THE NORTH OF 20N BETWEEN 45W AND 70W. A SHORTWAVE TROUGH WAS ROTATING AROUND THE SOUTHWEST PORTION OF THE LARGER CYCLONIC CIRCULATION SWEEPING ACROSS HISPANIOLA INTO THE CARIBBEAN. A SHORTWAVE RIDGE-TROUGH COUPLET COVERS THE ATLANTIC W OF 70W WITH THE TROUGH EXTENDING NORTHWARD ALONG THE EASTERN SEABOARD OF THE U.S. A BROAD FLAT UPPER LEVEL RIDGE EXTENDED ACROSS THE DEEP TROPICS ALONG 7N WITH A BROAD AREA OF CONFLUENT WESTERLY FLOW ALOFT DOMINATING THE REMAINDER OF THE TROPICAL AND SUBTROPICAL ATLANTIC FROM 10N TO 30N EAST OF 40W. AT THE SURFACE A COLD FRONT EXTENDED FROM 31N78W TO THE FLORIDA EAST COAST NEAR FORT PIERCE. SCATTERED SHOWERS AND THUNDERSTORMS WERE NOTED WITHIN 90 NM E OF THE FRONT N OF 27N MAINLY OVER THE ATLANTIC OCEAN WITH AN ISOLATED THUNDERSTORM NEAR PALM BEACH FLORIDA. ADDITIONAL SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EXTENDED OFF THE WINDWARD ISLANDS INTO THE ADJACENT ATLANTIC OCEAN WEST OF 55W. GENERALLY FAIR SKIES PREVAILED ELSEWHERE OVER THE ATLANTIC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB