000 AXNT20 KNHC 090513 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN AUG 09 2009 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 18W S OF 18N MOVING W NEAR 10 KT. LATEST INFRARED SATELLITE IMAGERY INDICATES THE WELL DEFINED LOW/MID LEVEL CYCLONIC CIRCULATION CENTER IS MOVING E OF THE WAVE AXIS WHICH IS EMBEDDED WITHIN THE MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ASSOCIATED WITH THE LOW/MID LEVEL CIRCULATION COVERING THE AREA FROM 11N-16N BETWEEN 19W-22W. TROPICAL WAVE IS ALONG 34W/35W S OF 19N MOVING W 10-15 KT. WAVE REMAINS EMBEDDED WITH A MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. THERE IS NO DEEP CONVECTION ASSOCIATED WITH THE WAVE BUT ISOLATED SHOWERS ARE WITHIN 120 NM EITHER SIDE OF THE WAVE AXIS FROM 6N-9N. TROPICAL WAVE IS ALONG 45W S OF 16N MOVING W NEAR 15 KT. WAVE REMAINS IN AN AREA OF RATHER DRY STABLE AIR. HOWEVER...SCATTERED MODERATE CONVECTION IS WITHIN 75 NM OF THE ITCZ AXIS JUST TO THE E OF THE WAVE TO 42W. TROPICAL WAVE IS ALONG 61W/62W S OF 18N MOVING WNW NEAR 15 KT. WAVE REMAINS IN AN AREA BENEATH AN UPPER RIDGE THUS MASKING THE WAVE SIGNATURE AND ANY SHOWERS/CONVECTION IS MORE ASSOCIATED WITH THE UPPER LEVEL FEATURE THAN THE WAVE ITSELF. TROPICAL WAVE IS ALONG 82W S OF 21N MOVING W NEAR 20 KT. WAVE IS NOW ALONG THE TRAILING EDGE OF A MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY AND IS EMBEDDED IN RATHER DRY STABLE AIR WITH NO ASSOCIATED DEEP CONVECTION. THE TROPICAL WAVE THAT WAS ALONG 96W IS NO LONGER IN THE ATLC BASIN. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N20W 10N39W 13N51W 11N61W. A SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ EXTENDING FROM 17N52W TO 9N54W WITH CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION W OF THE TROUGH AXIS WITHIN 60/75 NM OF LINE FROM 16N52W TO 13N59W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS N OF THE ITCZ WITHIN 45 NM OF 15N BETWEEN 28W-32W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE ANCHORED OVER SOUTH CAROLINA IS DIGGING S OVER THE FAR W ATLC AND THE FLORIDA PENINSULA PUSHING ANY SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INTO THE E GULF OF MEXICO WITHIN 120 NM ALONG THE COAST OF THE FLORIDA PENINSULA JUST N OF THE FLORIDA KEYS WITH ISOLATED SHOWERS N OF 26N E OF 87W. AN UPPER LEVEL TROUGH ANCHORED OVER CENTRAL MEXICO COVERS THE REMAINDER OF THE GULF. A SURFACE TROUGH IS OVER THE E BAY OF CAMPECHE/W YUCATAN PENINSULA FROM 22N89W TO 18N92W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM OF THE TROUGH AXIS. OTHERWISE THE REMAINDER OF THE GULF IS TRANQUIL TONIGHT. CARIBBEAN SEA... AN UPPER RIDGE OVER THE W ATLC/E GULF OF MEXICO COVERS THE NW CARIBBEAN WITH AN UPPER TROUGH OVER THE CENTRAL CARIBBEAN AND A SECOND UPPER RIDGE OVER THE E CARIBBEAN. THE UPPER LEVEL DIFFLUENCE OVER THE W CARIBBEAN IS GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS W OF 85W TO INLAND OVER CENTRAL AMERICA AND THE YUCATAN PENINSULA. THE ITCZ EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA TO COSTA RICA GENERATING SCATTERED SHOWERS/THUNDERSTORMS FROM 11N TO THE COAST OF PANAMA BETWEEN 77W-81W. FRESH TO STRONG TRADE WINDS CONTINUE ACROSS MOST OF THE CARIBBEAN USHERING IN FAST MOVING ISOLATED SHOWERS MAINLY ACROSS THE E CARIBBEAN E OF 70W WHILE THE REMAINDER OF THE AREA IS DOMINATED BY DRY STABLE AIR LIMITING SHOWER ACTIVITY. ATLANTIC OCEAN... AN UPPER RIDGE ANCHORED OVER SOUTH CAROLINA COVERS THE W ATLC WITH A NARROW UPPER TROUGH TO THE E EXTENDING THROUGH 32N57W ACROSS THE WINDWARD PASSAGE AND OVER THE CENTRAL CARIBBEAN. THIS COMBINATION IS PROVIDING UPPER LEVEL DIFFLUENCE TO GENERATE CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE FROM THE STRAITS OF FLORIDA NEAR 24N81W ACROSS THE BAHAMAS ALONG 27N72W TO BEYOND 32N64W. A SURFACE TROUGH IS BENEATH THE UPPER RIDGE EXTENDING FROM 31N71W TO OVER THE N MOST BAHAMA ISLANDS NEAR 26N78W BUT IS NOT GENERATING ANY SIGNIFICANT WEATHER. THE LARGE UPPER LOW OVER THE CENTRAL ATLC IS MOVING N AND CENTERED NEAR 32N47W WITH ANY SHOWER/THUNDERSTORM ACTIVITY N OF THE REGION AND A WEAKENING SURFACE TROUGH TO THE SW OF THE UPPER LOW EXTENDING FROM 31N52W TO 24N54W. THE REMAINDER OF THE ATLC REMAINS TRANQUIL AGAIN TONIGHT WITH A BROAD AREA OF SAHARAN DUST COVERING THE AREA E OF 50W AND FROM 65W-75W. $$ WALLACE