000 AXNT20 KNHC 022339 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN AUG 02 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 35W/36W S OF 15N MOVING W NEAR 15 KT. WEAK LOW AMPLITUDE WAVE WITH A WELL DEFINED CURVATURE EMBEDDED WITHIN THE ITCZ. ANY CONVECTION IS ASSOCIATED WITH THE ITCZ. TROPICAL WAVE EXTENDS FROM 21N66W ACROSS THE VIRGIN ISLANDS TO THE N COAST OF VENEZUELA NEAR 10N63W MOVING W NEAR 15 KT. THE N PORTION OF THE WAVE IS JUST TO THE E OF WELL DEFINED UPPER LOW ENHANCING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 22N TO OVER THE VIRGIN ISLANDS BETWEEN 62W AND THE WAVE AXIS. THE CARIBBEAN IS UNDER DRY STABLE AIR...THUS NO ACTIVITY. TROPICAL WAVE EXTENDS OVER THE YUCATAN PENINSULA FROM 21N89W THROUGH GUATEMALA AND INTO THE E PACIFIC REGION NEAR 14N91W MOVING W NEAR 15 KT. WAVE AXIS TRANSECTS AND UPPER LOW THAT INLAND OVER GUATEMALA/SE MEXICO ENHANCING SCATTERED SHOWERS/ THUNDERSTORMS MOVING W INTO THE E BAY OF CAMPECHE WITHIN 75 NM ALONG THE COAST S OF 21N E OF 93W. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N14W 10N22W 9N30W 11N36W 9N50W 10N62W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-11N BETWEEN 23W-26W WITH CLUSTERS OF SIMILAR CONVECTION WITHIN 120 NM ALONG THE COAST OF W AFRICA BETWEEN 10N-18N. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM EITHER SIDE OF THE ITCZ BETWEEN 32W-53W. ...DISCUSSION... GULF OF MEXICO... THE HEAVIEST WEATHER THIS EVENING IS IN THE E BAY OF CAMPECHE ASSOCIATED WITH A TROPICAL WAVE...SEE ABOVE. OTHERWISE...A BROAD SURFACE RIDGE COVERS THE GULF WITH THE AXIS EXTENDING FROM THE W ATLC ALONG 28N TO A 1018 MB HIGH NEAR 28N89W BRINGING GENERALLY FAIR WEATHER ACROSS MUCH OF THE REGION. AN UPPER HIGH OVER NE MEXICO/S TEXAS EXTENDS AN UPPER RIDGE E ACROSS THE GULF. DUE TO THIS UPPER RIDGE...AFTERNOON SHOWERS AND THUNDERSTORMS THAT HAVE GENERATED INLAND OVER THE SE US ARE MOVING OVER THE GULF WATERS FROM LOUISIANA TO THE FLORIDA PENINSULA. SOME ISOLATED SHOWERS ARE ACROSS THE CENTRAL GULF WITHIN 120 NM OF A LINE FROM 27N84W TO 24N95W. CARIBBEAN SEA... ALTHOUGH THERE IS A TROPICAL WAVE IN THE E CARIBBEAN AND A SECOND INLAND OVER THE YUCATAN PENINSULA...NEITHER ARE PRODUCING ANY SIGNIFICANT WEATHER FOR THE IMMEDIATE AREA. A BROAD UPPER RIDGE DOMINATES THE W CARIBBEAN EXTENDING FROM COLOMBIA TO CENTRAL CUBA AND COUPLED WITH THE UPPER LOW OVER GUATEMALA IS PROVIDING UPPER DIFFLUENCE TO GENERATE AN AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS MAINLY N OF 16N W OF 76W AND N OF 14N W OF 82W INCLUDING JAMAICA...CUBA...THE YUCATAN CHANNEL... AND PORTIONS OF CENTRAL AMERICA. THE ITCZ AXIS EXTENDS FROM COLOMBIA W INTO THE E PACIFIC REGION NEAR THE PANAMA/COSTA RICA BORDER GENERATING SCATTERED MODERATE/ISOLATED STRONG CONVECTION S OF 11N FROM 80W-83W. OTHERWISE...THE REMAINDER OF THE CARIBBEAN REMAINS RATHER TRANQUIL THIS EVENING. ATLANTIC OCEAN... SCATTERED SHOWERS/THUNDERSTORMS ARE MOVING OFF THE E COAST OF THE SE US INTO OVER THE W ATLC WITHIN 90/120 OF THE COAST N OF 29N IN RESPONSE TO AN UPPER TROUGH INLAND OVER THE US AND AN UPPER RIDGE THAT EXTENDS FROM THE W CARIBBEAN ACROSS CENTRAL CUBA TO BEYOND 32N73W. THERE ARE A PAIR OF UPPER LOWS OVER THE REMAINDER OF THE ATLC...ONE CENTERED NEAR 31N63W GENERATING SOME ISOLATED SHOWERS N OF 26N BETWEEN 60W-66W. A SECOND UPPER LOW IS CENTERED NEAR 28N42W WITH AN ASSOCIATED WEAK SURFACE TROUGH EXTENDING FROM 23N42W TO 28N43W AND NO SIGNIFICANT ACTIVITY ASSOCIATED WITH THIS FEATURE. THE TROPICAL WAVE OVER THE E CARIBBEAN IS PRODUCING SOME ACTIVITY N OF THE GREATER ANTILLES...SEE ABOVE. THE ENTIRE ATLC BASIN IS DOMINATED BY A SURFACE RIDGE ANCHORED N OF THE REGION WITH A WEAKNESS IN THE IMMEDIATE VICINITY OF THE SURFACE TROUGH. OTHERWISE THE REMAINDER OF THE ATLC IS TRANQUIL THIS EVENING WITH AN AREA OF SAHARAN DUST CLEARLY SEEN ON INFRARED SATELLITE IMAGERY E OF 54W FROM THE ITCZ TO 31N. $$ WALLACE