000 AXNT20 KNHC 091738 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN MAY 09 2010 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS 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 1715 UTC... ...TROPICAL WAVES... TROPICAL WAVE IS FROM 7N25W TO 1N27W MOVING W 10-15 KT. WAVE IS AT THE LEADING EDGE OF A MOISTURE MAXIMUM AS INDICATED BY THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 3N-6N BETWEEN 23W-28W. TROPICAL WAVE IS ALONG 39W S OF 7N MOVING W NEAR 5 KT. WAVE REMAINS RATHER ILL-DEFINED WAVE WITH NO ASSOCIATED CONVECTION. TROPICAL WAVE IS ALONG 54W/55W S OF 8N MOVING W NEAR 15 KT. WAVE IS EMBEDDED WITHIN A MOISTURE MAXIMUM AS INDICATED BY THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS FROM 8N TO INLAND OVER SOUTH AMERICA BETWEEN 52W-57W. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 10N12W 3N29W 5N35W 4N46W 4N52W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60/75 NM OF LINE FROM 3N47W TO JUST INLAND OVER BRAZIL SOUTH AMERICA NEAR 1N50W. CLUSTERS OF SIMILAR CONVECTION ARE WITHIN 30/45 NM OF LINE FROM 5N18W TO 7N22W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM OF THE ITCZ FROM 29W-35W. ...DISCUSSION... GULF OF MEXICO... AS OF 09/1500 UTC A COLD FRONT ENTERS THE GULF ACROSS CENTRAL FLORIDA BETWEEN VERO BEACH TO JUST N OF FORT MYERS TO 26N88W WHERE IT BEGINS TO RETREAT BACK N AS A WARM FRONT TO THE COAST OF TEXAS JUST S OF GALVESTON. THE UPPER LEVEL SUPPORT FOR THIS FRONT IS MOVING OFF THE COAST OF NEW ENGLAND. A PRE-FRONTAL TROUGH IS FROM GRAND BAHAMA ISLAND THROUGH THE FLORIDA STRAITS ALONG 24N81W TO JUST N OF THE YUCATAN CHANNEL NEAR 22N85W WITH SCATTERED SHOWERS ALONG THE TROUGH AXIS. THE GULF WATERS ARE DOMINATE BY AN UPPER LEVEL RIDGE THAT EXTENDS FROM THE W BAY OF CAMPECHE TO THE BIG BEND AREA OF FLORIDA. THIS UPPER RIDGE IS GIVING THE S GULF DRY STABLE AIR WITH STRONG SUBSIDENCE MOSTLY S OF 25N. ALSO AT 09/1500 UTC...A SURFACE TROUGH IS OVER THE SW GULF FROM 22N96W OVER THE BAY OF CAMPECHE TO NEAR 18N95W. LOW CLOUDS ARE BANKING WITHIN 75 NM W OF THE SURFACE TROUGH. OVERCAST MULTILAYERED CLOUDS WITH SCATTERED SHOWERS COVER E TEXAS AND LOUISIANA AND ARE MOVING INTO THE FAR NW GULF. DESPITE THE DRY AIRMASS THAT DOMINATES THE GULF...THE COMBINATION OF DIURNAL HEATING AND AVAILABLE LOW LEVEL MOISTURE IS EXPECTED TO GENERATE AFTERNOON SHOWERS AND POSSIBLE THUNDERSTORMS WITHIN 90 NM S OF THE COLD FRONT INLAND OVER THE FLORIDA PENINSULA. A SURFACE RIDGE IS BUILDING BEHIND THE FRONT ANCHORED BY A 1030 MB HIGH OVER THE UPPER MISSISSIPPI VALLEY. CARIBBEAN SEA... A 1008 MB LOW IS IN THE SW CARIBBEAN ALONG THE COAST OF COLOMBIA NEAR 9N77W WITH A SURFACE TROUGH EXTENDING S ACROSS PANAMA INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N E OF 78W TO INLAND OVER COLOMBIA AND PANAMA. AN UPPER RIDGE THAT COVERS THE GULF OF MEXICO COVERS THE NW CARIBBEAN WITH DRY STABLE AIR AND STRONG SUBSIDENCE N OF A LINE FROM HISPANIOLA TO THE THE BORDER OF PANAMA/COSTA RICA. A SECOND UPPER RIDGE ANCHORED OVER TROPICAL ATLC COVERS THE REMAINDER OF THE CARIBBEAN. THE TIGHT PRESSURE GRADIENT CONTINUES TO PROVIDE MODERATE/STRONG EASTERLY TRADE WINDS ACROSS THE CARIBBEAN WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. THESE TRADE WINDS ARE BANKING LOW LEVEL CLOUDS WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ALONG THE MOUNTAINS OF W PANAMA AND COSTA RICA INTO THE SW CARIBBEAN WITHIN 60 NM ALONG THE COAST BETWEEN THE PANAMA CANAL AND THE BORDER OF NICARAGUA. A WEAK SURFACE TROUGH REMAINS OVER THE NE CARIBBEAN FROM HISPANIOLA NEAR 18N69W NE INTO THE SW ATLC GENERATING SCATTERED SHOWERS OVER HISPANIOLA. THE TRADE WINDS ARE ALSO USHERING IN SOME ISOLATED LOW LEVEL FAST MOVING SHOWERS MAINLY ACROSS THE CENTRAL CARIBBEAN WHILE THE REMAINDER OF THE CARIBBEAN IS UNDER FAIR WEATHER CLOUDS THIS AFTERNOON. ATLANTIC OCEAN... AS OF 09/1500 UTC A COLD FRONT ENTERS THE W ATLC NEAR 32N73W TO ACROSS FLORIDA AND INTO THE GULF OF MEXICO NEAR VERO BEACH. A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 24N75W ACROSS GRAND BAHAMA ISLAND INTO THE GULF OF MEXICO THROUGH THE FLORIDA STRAITS NEAR 24N81W WITH SCATTERED SHOWERS ALONG THE SURFACE TROUGH. A WEAK SURFACE TROUGH EXTENDS FROM 22N65W TO OVER HISPANIOLA NEAR 18N69W GENERATING SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF THE TROUGH AXIS. A SECOND SURFACE TROUGH IS ALONG 62W FROM 23N-27N PRODUCING ISOLATED SHOWERS WITHIN 45 NM EITHER SIDE OF THE TROUGH AXIS. A BROAD SURFACE RIDGE DOMINATES THE REMAINDER OF THE W ATLC AND THE CENTRAL ATLC ANCHORED BY A 1024 MB HIGH NEAR 31N47W AND GIVING THE REMAINDER OF THE AREA W OF 30W FAIR WEATHER THIS AFTERNOON. A REMNANT SURFACE TROUGH IS OVER THE E ATLC EXTENDING FROM 30N12W ACROSS THE EASTERN MOST CANARY ISLANDS ALONG 24N21W TO 23N30W WITH ISOLATED SHOWERS WITHIN 45 NM EITHER SIDE OF THE TROUGH AXIS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALLACE