000 AXNT20 KNHC 191034 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON MAY 19 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS TITLED ALONG 40W/41W S OF 13N MOVING W 10-15 KT. EARLY MORNING VIS IMAGES SHOW A FAINT APEX OR WEAK INVERTED V PATTERN IN THE LOW-LEVEL CLOUDS. HOWEVER...MOST OF THE SCATTERED SHOWERS AND TSTMS ARE LINEAR IN STRUCTURE AND EMBEDDED WITHIN THE ITCZ WITHIN 300 NM EITHER SIDE OF THE AXIS FROM 3N-8N. A TROPICAL WAVE HAS BEEN ADJUSTED W SLIGHTLY IN THE CARIBBEAN ALONG 65W/66W S OF 13N MOVING W 10-15 KT. THE ADJUSTMENT WAS BASED ON A WWD MOVING MOISTURE BULGE EVIDENT ON THE MIMIC TPW ANIMATION THAT IS VERY LIKELY ASSOCIATED WITH THIS WEAK FEATURE. MUCH OF THE WAVE IS NOW INLAND OVER SOUTH AMERICA...WHICH WILL MAKE IT DIFFICULT TO TRACK FOR THE NEXT COUPLE OF DAYS. THIS WAVE MAY BE ENHANCING CONVECTION W OF THE AXIS OVER WRN VENEZUELA. ..THE ITCZ... ITCZ AXIS IS CENTERED ALONG 8N13W 5N20W 4N30W 4N40W 3N52W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 1N-8N E OF 16W AND FROM 4N-7N BETWEEN 48W-55W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 22W-30W. ...DISCUSSION... THE GULF OF MEXICO... STRONG SW FLOW ALOFT LIES OVER MUCH OF THE GULF OF MEXICO MOISTENING THE MID AND UPPER LEVELS SE OF A LINE FROM NE MEXICO TO THE BIG BEND AREA OF FLORIDA. THE COMBINATION OF THIS UPPER FLOW REGIME AND LOW-LEVEL CONVERGENCE ALONG A DISSIPATING FRONTAL BOUNDARY FROM N FLORIDA TO 22N92W IS PRODUCING SCATTERED SHOWERS AND TSTMS WITHIN 90 NM OF THE FRONT E OF 90W...INCLUDING A 60 NM BAND OF SHOWERS N OF A LINE FROM SARASOTA TO VERO BEACH FLORIDA. SIMILAR ACTIVITY IS OVER THE S BAY OF CAMPECHE DRAWN FROM THE TROPICAL EPAC AND ENHANCED BY DIFFLUENT FLOW ALOFT. DRIER AIR HAS WORKED SE OVER THE REMAINDER OF THE GULF SUPPRESSING DEEP CLOUD FORMATION. SFC WINDS ARE MAINLY LIGHT ACROSS THE REGION DUE TO THE WEAK FRONT AND A 1013 MB HIGH OVER THE NW GULF. THE CARIBBEAN SEA... LARGE SCALE MID TO UPPER RIDGING LIES OVER THE REGION...THOUGH IT IS INTERRUPTED SLIGHTLY BY A SMALL UPPER LOW NEAR 16N66W. THE UPPER LOW AND MUCH OF THE AREA N OF 14N IS EMBEDDED IN A SUBSIDENT ENVIRONMENT...PROVIDING WIDESPREAD FAIR WEATHER BESIDES FOR A PASSING SHOWER OR TWO N OF 16N E OF 80W. S OF 14N...THERE IS A FAIR AMOUNT OF MOISTURE IN PLACE BUT MOST OF THE DEEP CONVECTIVE ACTIVITY IS INLAND OVER SOUTH AMERICA. HOWEVER...SOME OF THESE PATCHES HAVE MOVED INTO THE SW CARIB WATERS S OF 13N W OF 76W OVER THE PAST FEW HOURS. ELY TRADES ARE MAINLY MODERATE ACROSS THE CENTRAL AND E PORTIONS. THESE WINDS VEER SE OVER THE NW WATERS IN RESPONSE TO THE FRONT IN THE GULF OF MEXICO. LITTLE SIGNIFICANT CHANGE IS EXPECTED OVER THE NEXT DAY OR SO. THE ATLANTIC OCEAN... SFC HIGH PRES CENTERED S OF THE AZORES NEAR 33N26W DOMINATES THE THE SFC PATTERN THIS MORNING. THIS FEATURE IS PROVIDING MAINLY LIGHT WINDS ACROSS THE BULK OF THE SUBTROPICS...EXCEPT FOR THE FAR NW PORTION WHERE THE PRESSURE GRADIENT TIGHTENS IN RESPONSE TO A LOW PRES SYSTEM OVER SOUTHERN CANADA. IN FACT...GALE CONDITIONS HAVE DEVELOPED JUST N OF OUR FORECAST AREA OFF THE SE CONUS. N TO NE WINDS ARE ALSO ENHANCED NEAR THE COAST OF AFRICA FROM 16N-28N DUE TO INVERTED TROUGHING OVER THE CONTINENT. IN THE MID AND UPPER LEVELS...A LARGE SCALE RIDGE LIES OVER MUCH OF THE CENTRAL AND WESTERN ATLANTIC POSITIONED NEAR 22N66W. THIS BROAD SYSTEM IS PROVIDING DRY STABLE AIR ALOFT ACROSS MUCH OF THE AREA W OF 50W. AN UPPER TROUGH LIES ALONG 32W/33W PRODUCING SCATTERED SHOWERS FROM 23N-27N BETWEEN 28W-32W. AN ASSOCIATED BENIGN SFC TROUGH...REMNANTS OF A FRONT...EXTENDS FROM 31N42W TO 25N47W. RIDGING LIES OVER THE DEEP TROPICS WITH ONE ANTICYCLONE CENTERED OVER W AFRICA NEAR 12N14W AND ANOTHER OVER VENEZUELA NEAR 8N63W. DIFFLUENT FLOW ALOFT BETWEEN THESE SYSTEMS MAY BE ENHANCING CONVECTION WITHIN THE ITCZ. VISIBILITY IS LIKELY REDUCED IN THE SMOKE PLUMES DIRECTLY DOWNWIND FROM BRUSH FIRES NEAR LAKE OKEECHOBEE FLORIDA...NEAR MIAMI FLORIDA AND ABACO BAHAMAS. $$ CANGIALOSI