000 AXNT20 KNHC 082344 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU MAY 08 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 32W S OF 9N MOVING W 15-20 KT. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 120 NM AHEAD OF THE WAVE AXIS AND N OF 4N. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 5N10W 4N20W 2N30W 2N34 CROSSING THE EQUATOR AT 38W INTO NE BRAZIL NEAR 3S42W. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE OVER SW AFRICA AND NEAR 7N19W. SIMILAR CONVECTION IS OVER NE BRAZIL NEAR THE ITCZ AXIS. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER LEVEL RIDGE ANCHORED ON A HIGH OVER CENTRAL MEXICO DOMINATES THE ENTIRE GULF WHILE A SHORT WAVE TROUGH IS MOVING ACROSS THE SE CONUS. AT THE SURFACE...A RIDGE ALSO COVERS MOST OF THE GULF REGION. UNDER THE INFLUENCE OF THE RIDGE...LIGHT TO MODERATE SOUTHERLY FLOW AND MOSTLY FAIR WEATHER PREVAIL. THESE WINDS ARE FORECAST TO INCREASE OVER THE W GULF SAT AHEAD OF LOW PRES MOVING THROUGH THE MISSISSIPPI VALLEY. WINDS WILL DIMINISH SUN AS A COLD FRONT MOVES INTO THE NW WATERS. LATEST SATELLITE IMAGERY INDICATES THAT THE COLD FRONT OVER THE NW PORTION OF THE GULF HAS DISSIPATED. IN ADDITION...AN EARLIER ASCAT PASS SHOWED SWLY WINDS OVER THE ENTIRE NW GULF WATERS. CARIBBEAN SEA... THE UPPER-LEVEL HIGH CENTERED OVER CENTRAL MEXICO ALSO EXTENDS A RIDGE OVER WESTERN CUBA...THE WESTERN CARIBBEAN AND NORTHERN CENTRAL AMERICA. ANOTHER UPPER LEVEL ANTICYCLONIC CIRCULATION CENTER IS OVER FRENCH GUIANA WITH RIDGE AXIS EXTENDING ACROSS TRINIDAD AND TOBAGO NORTHWESTWARD ACROSS THE CARIBBEAN SEA TO PUERTO RICO. SWLY UPPER-LEVEL FLOW ON THE WESTERN PERIPHERY OF THIS RIDGE IS ENHANCING THE DEVELOPMENT OF MODERATE TO STRONG CONVECTION OVER WESTERN VENEZUELA AND PARTS OF COSTA RICA AND PANAMA. THESE WINDS ARE ALSO ADVECTING ABUNDANT UPPER LEVEL MOISTURE FROM SOUTH AMERICA TO OVER THE CENTRAL AND EASTERN PORTIONS OF THE BASIN. BETWEEN RIDGES...AN ELONGATED UPPER LEVEL TROUGH EXTENDS FROM THE SRN BAHAMAS TO THE ATLC COAST OF NICARAGUA. THE COMBINATION OF A SFC HIGH LOCATED N OF AREA NEAR BERMUDA AND THE COLOMBIAN LOW IS PRODUCING MODERATE TO FRESH TRADE WINDS ACROSS THE EAST AND CENTRAL CARIBBEAN WITH THE STRONGEST WINDS IN THE RANGE OF 25 TO 30 KT JUST OFF SHORE THE COLOMBIAN COAST. THESE WINDS ARE EXPECTED TO PERSIST DURING THE NEXT 24 TO 48 HOURS AS THE ATLC HIGH PRES SLIDES SLOWLY EWD. ATLANTIC OCEAN... A 1021 MB SURFACE HIGH IS LOCATED JUST SE OF BERMUDA NEAR 31N64W. THIS HIGH ENVELOPS THE BAHAMAS...FLORIDA AND THE EASTERN GULF OF MEXICO. ANOTHER 1025 MB HIGH PRESSURE CENTER NEAR 33N31W EXTENDS A RIDGE OVER THE E ATLC GIVING THE AREA MOSTLY FAIR WEATHER. ALOFT...BROAD UPPER TROUGH REMAINS OVER THE W-CENTRAL ATLC BETWEEN 50W AND 75W DIPPING S INTO THE CARIBBEAN SEA THROUGH THE WINDWARD PASSAGE. THE ASSOCIATED COLD FRONT ENTERS THE AREA NEAR 31N49W THEN CONTINUES SW AND THEN W TO NEAR 25N63W. SCATTERED SHOWERS ARE WITHIN 200 NM AHEAD OF THE FRONT AND N OF 25N. THE REMAINDER OF THE ATLC IS DOMINATE BY AN UPPER RIDGE ANCHORED SE OF THE CAPE VERDE ISLANDS NEAR 10N20W. THE SAHARAN AIR LAYER PRODUCT FROM CIMSS SHOWS THAT DUST CONTINUES TO STREAM OFF THE W AFRICAN COAST S OF 20N AND COVERS THE TROPICAL ATLC WESTWARD TO THE LESSER ANTILLES WHERE THERE ARE SEVERAL REPORTS OF HAZE. TRACES OF SAHARAN DUST WERE ALSO VISIBLE ACROSS THE PUERTO RICO AND THE VIRGIN ISLANDS TODAY. $$ GR