000 AXNT20 KNHC 261030 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU JUL 26 2007 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 0945 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 29W/30W S OF 18N MOVING W 15 KT. LOW LEVEL INVERTED-V SIGNATURE IS OBSERVED COVERING THE AREA FROM 25W-32W. SMALL CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 12N-14W BETWEEN 26W-33W. TROPICAL WAVE IS SLIGHTLY TILTED ALONG 43W/44W S OF 16N MOVING W 15 KT. VERY LOW AMPLITUDE LOW LEVEL INVERTED-V SIGNATURE IS OBSERVED COVERING THE AREA FROM 38W-47W. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE WITHIN 60 NM OF LINE FROM 12N42W TO 10N47W. TROPICAL WAVE IS ALONG 69W S OF 15N MOVING W NEAR 25 KT. WEAK WAVE WITH SHALLOW LOW LEVEL INVERTED-V SIGNATURE COVERING THE AREA FROM 66W-74W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 13N-16N BETWEEN 68W-74W. TROPICAL WAVE THAT WAS ALONG 90W WAS RELOCATED FURTHER W BASED ON PREVIOUS SPEED...SURFACE OBSERVATIONS...AND LOW LEVEL INVERTED-V SIGNATURE IS NOW VISIBLE AS THE WAVE HAS MOVED W OF THE LARGE UPPER HIGH THAT WAS MASKING THE SIGNATURE. WAVE AXIS EXTENDS FROM 24N94W ACROSS MEXICO NEAR 18N96W INTO THE E PACIFIC REGION MOVING W 20-25 KT. CONVECTION IN THE VICINITY OF THE WAVE IS ASSOCIATED WITH THE LARGE UPPER HIGH OVER THE YUCATAN CHANNEL. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 11N12W 9N23W 9N37W 11N43W 9N53W 10N62W. MOST ACTIVITY IS ASSOCIATED WITH THE TROPICAL WAVES. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM OF 12N FROM 34W-38W. SCATTERED SHOWERS ARE FROM 6N-14N E OF 19W TOP THE COAST OF W AFRICA. ...DISCUSSION... GULF OF MEXICO... LARGE UPPER HIGH OVER THE YUCATAN CHANNEL DOMINATES THE GULF GENERATING SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 120 NM OF LINE FROM 27N88W TO 23N95W WHICH IS ENHANCED BY THE TROPICAL WAVE. AN UPPER LOW IN S/CENTRAL TEXAS IS AIDING IN THE DEVELOPMENT OF SCATTERED SHOWERS/THUNDERSTORMS THAT ARE OVER THE W GULF W OF 95W WITH THE LARGEST CLUSTERS OF THUNDERSTORMS ALONG THE TEXAS COAST BETWEEN CORPUS CHRISTI AND GALVESTON. WIDELY ISOLATED SHOWERS ARE OVER THE SE GULF S OF 26N E OF 84W. CARIBBEAN SEA... LARGE UPPER HIGH IS OVER THE YUCATAN CHANNEL DOMINATING THE AREA W OF 76W AND EXTENDING OVER THE GULF OF MEXICO AND THE SW ATLC AND GENERATING CLUSTERS OF SCATTERED SHOWERS/THUNDERSTORMS N OF 17N FROM 74W-84W. UPPER RIDGE EXTENDING FROM THE W TROPICAL ATLC COVERS THE REMAINDER OF THE CARIBBEAN CREATING A WEAK UPPER LEVEL INVERTED TROUGH EXTENDING FROM PANAMA TO HISPANIOLA WITH DRY STABLE AIR COVERING THE E CARIBBEAN E OF 77W. THE ITCZ AXIS EXTENDS FROM ACROSS COLOMBIA/PANAMA AND COSTA RICA INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N TO INLAND OVER PANAMA BETWEEN 77W-82W. ATLANTIC OCEAN... LARGE UPPER HIGH OVER THE YUCATAN CHANNEL EXTENDS A OVER THE SW ATLC WITH AN ADDITIONAL RIDGE AXIS EXTENDING FROM THE CENTRAL BAHAMAS NE TO JUST E OF BERMUDA NEAR 30N70W GENERATING ISOLATED SHOWERS/THUNDERSTORMS W OF 78W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 26N31N BETWEEN 67W-72W. LARGE UPPER LOW IN THE W/CENTRAL ATLC IS CENTERED NEAR 31N57W COVERING THE AREA N OF 22N FROM 46W-64W WITH CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 26N BETWEEN 50W-63W. BENIGN UPPER LEVEL RIDGE/TROUGH/RIDGE WITH DRY STABLE AIR AND A STRONG SURFACE RIDGE DOMINATE THE REMAINDER OF THE ATLC WITH THE SURFACE RIDGE ANCHORED BY A SERIES OF HIGHS N OF THE REGION PRODUCING ONLY FAIR WEATHER CLOUDS ACROSS THE REMAINDER OF THE AREA. $$ WALLACE