000 AXNT20 KNHC 110528 RRA TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SUN MAR 11 2007 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...METEOROLOGICAL ANALYSIS... WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N10W 4N21W 2N28W EQ36W 1S43W AND INTO NE BRAZIL NEAR 3S46W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM N OF THE AXIS BETWEEN 22W-30W. SCATTERED SHOWERS AND TSTMS ARE WITHIN 60 NM EITHER SIDE E OF 22W. ...DISCUSSION... GULF OF MEXICO... WEAK SFC HIGH PRES RIDGING CONTINUES TO DOMINATE MUCH OF THE GULF...WHILE A VERY WEAK SFC TROUGH REMAINS NEARLY STATIONARY ALONG 88W FROM 25N-29N. THIS TROUGH IS NOW PRODUCING LITTLE IF ANY CLOUDINESS AND MAY BE REMOVED FROM THE 0600 UTC ANALYSIS. LIGHT TO MODERATE ELY SFC WINDS COVER THE REGION THIS EVENING BUT THEY WILL LIKELY INCREASE OVER THE NEXT DAY OR TWO AS STRONG HIGH PRES IN THE UPPER MIDWEST SURGES SE. IN THE UPPER LEVELS...STRONG ZONAL FLOW DOMINATES MUCH OF THE BASIN BETWEEN RIDGING EXTENDING N FROM NICARAGUA AND A COUPLE OF SHORTWAVE TROUGHS PUSHING THROUGH THE CONUS AND OFF THE E COAST. THESE WINDS ARE ADVECTING ABUNDANT UPPER LEVEL MOISTURE/HIGH CLOUDS FROM THE EPAC ACROSS CENTRAL MEXICO INTO THE GULF MAINLY S OF 25N. GFS SHOWS THE UPPER SHORTWAVE TROUGH...CURRENTLY OVER THE SW U.S...CUTTING OFF AND BECOMING NEARLY STATIONARY OVER NEW MEXICO/WRN TEXAS DURING THE NEXT COUPLE OF DAYS. THIS MAY INCREASE MOISTURE INTO THE NW GULF AS THE UPPER FLOW VEERS SWLY. CARIBBEAN... AN UPPER LEVEL HIGH CENTERED IN THE SW CARIB NEAR 12N77W IS THE MAIN WEATHER FEATURE IN THE REGION. STRONG WLY WINDS ON THE NRN PERIPHERY OF THE RIDGE IS ADVECTING A SWATH OF HIGH CLOUDS ACROSS THE S GULF...THE YUCATAN PENINSULA...CUBA AND INTO THE SW ATLC. ELSEWHERE QUIET WEATHER PERSISTS WITH PLENTY OF DRY STABLE AIR ALOFT IN PLACE. SLIGHT UPPER LEVEL TROUGHING EXISTS ACROSS THE LESSER ANTILLES WITH UPPER CONFLUENCE ENHANCING SUBSIDENT FLOW S OF 15N. FAIR WEATHER AND ISOLATED TRADE WIND SHOWERS ARE SEEN ACROSS THE AREA. CLUSTERS OF MODERATE CONVECTION ARE NOTED OVER COLOMBIA AND THE ATLC COASTAL WATERS OF COSTA RICA AND W PANAMA ENHANCED BY A DIFFLUENT PATTERN ALOFT. TRANQUIL WEATHER AND MODERATE TO FRESH TRADES ARE EXPECTED TO CONTINUE INTO THE EARLY PART OF THE WORK WEEK. WESTERN ATLANTIC... MESSY WEATHER CONTINUES FOR PARTS OF THE REGION. THE SYNOPSIS PRODUCING THIS UNSETTLED WEATHER REMAINS FAIRLY COMPLEX. STARTING IN THE UPPER LEVELS...A SHORTWAVE TROUGH LIES ALONG 74W. UPPER ENERGY/VORTICITY ASSOCIATED WITH THE SHORTWAVE IS PRODUCING A SPIN IN THE CLOUDS AND LIKELY SOME SCATTERED SHOWERS N OF 28N BETWEEN 70W-78W. SWLY UPPER LEVEL FLOW TO THE E OF THE AXIS ALONG WITH A HIGHLY DIFFLUENT PATTERN ARE SIGNIFICANT FACTORS FOR THE DEEPER MOISTURE FURTHER E. THE CONTRIBUTING SFC FACTORS CONSIST OF A DEVELOPING AREA OF LOW PRES NEAR 31N64W AND A 1011 MB LOW FURTHER SW NEAR 26N71W. A SFC TROUGH OR WEAK FRONTAL BOUNDARY CONNECTS THESE TWO LOW PRES SYSTEMS AND EXTENDS FURTHER S TO HISPANIOLA. ALL OF THESE ELEMENTS ARE AIDING IN PRODUCING A SWATH OF DEEP MOISTURE N OF 27N BETWEEN 57W-68W AND FROM 19N-27N BETWEEN 62W-68W. IN ADDITION...STRONG WINDS ARE A HIGH CONCERN AS A TIGHT SFC PRESSURE GRADIENT EXISTS BETWEEN THE LOW PRES SYSTEMS MENTIONED AND A 1037 MB HIGH NEAR 41N55W. UP TO GALE FORCE WINDS ARE OCCURRING N OF 28N BETWEEN 60W-64W. LOOKING AHEAD...THE NRN LOW PRES SYSTEM IS EXPECTED TO BECOME THE DOMINATE AS IT DEEPENS AND TRACKS RATHER QUICKLY N OF THE AREA TODAY. HOWEVER THE ASSOCIATED TRAILING TROUGH WILL REMAIN IN THE REGION FOR THE NEXT COUPLE OF DAYS. EASTERN ATLANTIC... STRONG HIGH PRESSURE RIDGING CONTINUES TO DOMINATE THE SFC PATTERN ACROSS THE ATLC E OF 45W-50W. THIS HIGH IS PRODUCING MODERATE TO FRESH TRADE WINDS AND FAIR WEATHER ACROSS A GOOD PORTION OF THE AREA. IN THE MID AND UPPER LEVELS...STRONG RIDGING ALSO DOMINATES WITH A HIGH CENTER NEAR 22N31W. DRY AND STABLE AIR ALOFT RESULTING IN STRONG SUBSIDENCE IS KEEPING THE AREA MAINLY SHOWER FREE. THE TRADE WINDS ARE SET TO PICK UP AGAIN FROM W TO E STARTING TODAY INTO NEXT WEEK AS STRONG HIGH PRES REBUILDS E ACROSS THE ATLC OCEAN. UPPER RIDGING WILL ALSO REMAIN IN CONTROL PROMOTING THE CONTINUATION OF FAIR WEATHER. $$ CANGIALOSI