000 AXNT20 KNHC 280614 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED JUN 28 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...SPECIAL FEATURES... A 1013 MB LOW PRESSURE CENTER IS ALONG THE NORTHEASTERN NORTH CAROLINA/SOUTHEASTERN VIRGINIA BORDER. SURFACE OBSERVATIONS INDICATE THAT GALE FORCE WINDS ARE OCCURRING OVER PARTS OF CHESAPEAKE BAY AS THE LOW CENTER MOVES ACROSS THE BAY. THE LOW CENTER HAS LIMITED AND POORLY ORGANIZED THUNDERSTORM ACTIVITY. GALE WARNINGS ARE ALREADY IN PLACE FOR THE AFFECTED AREAS...PLEASE CONSULT FORECASTS AND BULLETINS ISSUED BY YOUR LOCAL NWS FORECAST OFFICE CONCERNING GALE WARNINGS AND ANY RAINFALL AND/OR FLOOD STATEMENTS. THE LOW CENTER IS EXPECTED TO CONTINUE TO MOVE RAPIDLY NORTH-NORTHEASTWARD AND MERGE WITH A FRONTAL ZONE BY LATE TODAY. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 53W/54W SOUTH OF 15N MOVING WEST 15 KT. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS...POSSIBLY MORE ITCZ-RELATED THAN DIRECTLY RELATED JUST TO THIS WAVE...ARE FOUND FROM 4N TO 11N BETWEEN 46W AND 55W. SCATTERED MODERATE TO STRONG SHOWERS AND THUNDERSTORMS ARE TO THE WEST OF THE WAVE FROM 8N TO 10N BETWEEN 57W AND 60W. THIS PRECIPITATION ALSO MAY BE MORE DIRECTLY RELATED TO THE ITCZ THAN TO THIS WAVE. THIS SYSTEM IS POORLY ORGANIZED AT THIS TIME...BUT IT IS EXPECTED TO BRING BRIEFLY HEAVY RAINS AND GUSTY WINDS TO THE WINDWARD ISLANDS ON TODAY. DEVELOPMENT OF THIS SYSTEM...IF ANY...IS EXPECTED TO BE SLOW TO OCCUR. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 39W SOUTH OF 11N MOVING WEST 10 TO 15 KT. NO SHOWERS AND THUNDERSTORMS ARE DIRECTLY RELATED TO THIS WAVE. A TROPICAL WAVE IS ALONG 90W SOUTH OF 20N MOVING WEST 10 TO 15 KT. SHOWERS AND THUNDERSTORMS WERE OCCURRING EARLIER IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...JUST OFF THE WESTERN YUCATAN PENINSULA. THE CLOUD TOP TEMPERATURES HAVE BEEN WARMING DURING THE LAST 4 TO 5 HOURS AND THE PRECIPITATION HAS BEEN WEAKENING. ...THE ITCZ... ITCZ 11N14W 7N20W 5N26W 5N37W 7N42W 11N52W 11N55W 9N61W. WIDELY SCATTERED TO SCATTERED MODERATE SHOWERS/ISOLATED STRONG THUNDERSTORMS ARE FOUND FROM 3N TO 9N BETWEEN 18W AND 40W. ISOLATED MODERATE SHOWERS ARE ELSEWHERE FROM 3N TO 12N BETWEEN 40W AND 50W. ...DISCUSSION... THE GULF OF MEXICO... THE SOUTHERN GULF OF MEXICO IS UNDER THE INFLUENCE OF THE UPPER LEVEL ANTICYCLONIC FLOW FROM THE WESTERN CARIBBEAN SEA RIDGE. MOST OF THE MIDDLE TO UPPER LEVEL FLOW OVER THE OPEN GULF WATERS IS WESTERLY. THE GULF WATERS FIND THEMSELVES TO THE SOUTH OF THE BASE OF A DEEP LAYER TROUGH WHICH COVERS THE EASTERN HALF OF THE CONTIGUOUS U.S.A. WEAK CYCLONIC FLOW/TROUGH IS ALONG THE FLORIDA EAST COAST. THIS WEAK AREA OF CYCLONIC FLOW IS SQUEEZED INTO AN AREA NEAR A WEAK RIDGE WHICH EXTENDS TO THE NORTH OF THE BAHAMAS THE CYCLONIC FLOW FROM THE APPROACHING 30N61W MIDDLE TO UPPER LEVEL LOW CENTER. A SURFACE TROUGH 31N89W 25N93W IS A DEFAULT FEATURE IN THE MIDDLE HIGH PRESSURE FROM THE ATLANTIC OCEAN REACHING THE EASTERN GULF OF MEXICO...AND HIGH PRESSURE FROM TEXAS INTO THE WESTERN GULF. THE CARIBBEAN SEA... THE TROPICAL WAVE FROM 18 TO 24 HOURS AGO HAS MOVED TO 90W... ADDING SOME INSTABILITY TO THE ATMOSPHERE IN THE SOUTHWESTERN GULF OF MEXICO. STRONG SHOWERS AND THUNDERSTORMS ARE IN CENTRAL EL SALVADOR. THE CLOUD TOP TEMPERATURES HAVE BEEN WARMING IN THE AREAS OF SHOWERS AND THUNDERSTORMS FROM COSTA RICA TO BELIZE DURING THE LAST FEW HOURS...IN THE COASTAL WATERS AND CARIBBEAN SEA WEST OF 80W AND IN INTERIOR AREAS OF CENTRAL AMERICA. AN UPPER LEVEL RIDGE REMAINS IN THE WESTERN CARIBBEAN SEA. A MIDDLE TO UPPER LEVEL TROUGH RUNS FROM AN ATLANTIC OCEAN 30N61W LOW CENTER TO 24N67W...INTO THE CARIBBEAN SEA NEAR 16N68W...TOWARD THE NETHERLANDS ANTILLES AND THE NORTHWESTERN VENEZUELA COAST. NUMEROUS STRONG THUNDERSTORMS ARE FOUND IN NORTHWESTERN COLOMBIA FROM 6N TO 9N BETWEEN 75W AND 77W PROBABLY NEAR THE ITCZ. THE ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL TROUGH GOES FROM A 32N46W LOW CENTER TO A 30N61W LOW CENTER TO 24N67W TO THE CARIBBEAN SEA NEAR 16N68W TOWARD THE NETHERLANDS ANTILLES AND THE NORTHWESTERN VENEZUELA COAST. AN UPPER LEVEL RIDGE EXTENDS FROM THE TROPICAL ATLANTIC OCEAN JUST EAST OF THE SOUTHEASTERN CARIBBEAN SEA NEAR 11N58W TO 20N50W 25N40W BEYOND 32N40W. A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM THE MADEIRA ISLANDS TO 24N25W TO JUST WEST OF THE CAPE VERDE ISLANDS. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS COVER THE AREA NORTH OF 20N BETWEEN 50W AND 70W. A SURFACE TROUGH DISRUPTS THE BROAD SURFACE ANTICYCLONIC FLOW OF THE ATLANTIC OCEAN ALONG THE LINE FROM 31N53W 27N60W 20N69W. $$ MT