000 AXNT20 KNHC 191038 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU JUL 19 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 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS TITLED ALONG 21N33W THROUGH A WEAKENING 1012 MB LOW NEAR 12N37W 6N39W MOVING W 15-20 KT. BROAD WAVE LOW/MID LEVEL INVERTED-V CURVATURE COVERING THE AREA FROM 30N-44N. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS AT THE BASE OF THE WAVE AXIS FROM 6N-9N BETWEEN 36W-40W. TROPICAL WAVE IS SLIGHTLY TILTED ALONG 20N61W 14N64W 6N64W MOVING W 15-20 KT. BROAD WAVE WITH LOW/MID LEVEL INVERTED-V CURVATURE COVERING THE AREA FROM 55W-70W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVER THE AREA FROM 12N-19N BETWEEN 59W-69W INCLUDING THE LESSER ANTILLES. SCATTERED MODERATE/STRONG CONVECTION IS S OF 12N TO INLAND OVER SOUTH AMERICA FROM TRINIDAD TO THE ABC ISLANDS. TROPICAL WAVE IS ALONG 91W/92W S OF 19N MOVING W 15-20 KT. WAVE REMAINS INLAND OVER THE YUCATAN PENINSULA WITH ASSOCIATED DEEP CONVECTION IN THE E PACIFIC REGION. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 10N12W 9N17W 12N34W 8N53W 11N62W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 90/120 NM OF THE AXIS FROM 54W-57W. CLUSTERS OF SIMILAR CONVECTION ARE FROM 6N-14N E OF 20W TO JUST INLAND OVER AFRICA...POSSIBLY ASSOCIATED WITH THE NEXT TROPICAL WAVE. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL RIDGE EXTENDS FROM THE E PACIFIC REGION ACROSS MEXICO INTO THE W GULF TO THE N GULF COAST NEAR 32N92W ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS W OF 95W. THE 1011 MB LOW PREVIOUSLY ALONG THE COAST OF MEXICO NEAR 24N98W HAS LOST ITS IDENTITY BUT THE WEAK SURFACE TROUGH NOW EXTENDS INLAND OVER NE MEXICO NEAR 23N99W TO TEXAS NEAR 29N97W. WEAK UPPER RIDGE EXTENDS ACROSS THE N GULF ALONG 93W ACROSS FLORIDA INTO THE W ATLC ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER N OF 27N FROM 89W-95W. THE CUT-OFF UPPER LOW CENTERED OVER THE CAYMAN ISLANDS COVERS THE AREA S OF 26N E OF 89W INTO THE W ATLC GENERATING ISOLATED SHOWERS/THUNDERSTORMS OVER THE SAME AREA. OTHERWISE A WEAK SURFACE RIDGE REMAINS ACROSS THE GULF FROM THE W ATLC WITH A 1018 MB HIGH INLAND OVER SE LOUISIANA. CARIBBEAN SEA... AN ELONGATED CUT-OFF UPPER LOW REMAINS CENTERED OVER THE CAYMAN ISLANDS NEAR 19N81W COVERING THE AREA N OF 16N FROM 74W TO THE YUCATAN PENINSULA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM N OF 18N W OF 78W ACROSS CUBA AND TO THE YUCATAN PENINSULA. WEAKENING UPPER RIDGE EXTENDS FROM THE COLOMBIA/PANAMA BORDER NW TO ACROSS CENTRAL AMERICA NEAR CENTRAL NICARAGUA. BROAD UPPER HIGH IS BEGINNING TO DOMINATE THE CARIBBEAN CENTERED E OF THE LESSER ANTILLES EXTENDING A RIDGE AXIS W INTO THE CARIBBEAN TO NEAR 14N75W. DRY STABLE AIR COVERS THE CENTRAL CARIBBEAN FROM 70W-77W WHILE THE E CARIBBEAN IS UNDER THE INFLUENCE OF THE TROPICAL WAVE THAT EXTENDS ACROSS THE LESSER ANTILLES. MODERATE/STRONG EASTERLY TRADE WINDS CONTINUE ACROSS THE CARIBBEAN S OF 15N. ATLANTIC OCEAN... WEAK UPPER RIDGE FROM THE GULF OF MEXICO EXTENDS ACROSS N FLORIDA INTO THE W ATLC TO 73W. CUT-OFF UPPER LOW OVER THE CAYMAN ISLANDS COVERS THE SW ATLC S OF 25N W OF 74W GENERATING ISOLATED SHOWERS S OF 25N W OF 77W INTO THE STRAITS OF FLORIDA. AN UPPER LOW REMAINS IN THE W/CENTRAL ATLC NEAR 26N67W COVERING THE AREA N OF 22N FROM 62W-70W WITH A PERSISTENT SURFACE TROUGH EXTENDING FROM 31N65W TO 25N65W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS TO THE E OF THE TROUGH FROM 25N-31N BETWEEN 57W-65W. UPPER HIGH IS IN THE W TROPICAL ATLC E OF THE LESSER ANTILLES NEAR 15N59W EXTENDS A RIDGE AXIS N TO 28N59W ENHANCING THE ABOVE SHOWER/THUNDERSTORM ACTIVITY. AN THE UPPER TROUGH IN THE E/CENTRAL ATLC IS NOW A CUT-OFF UPPER LOW CENTERED NEAR 25N49W COVERING THE AREA N OF 20N FROM 39W-54W. ANOTHER UPPER RIDGE EXTENDS OFF THE COAST OF AFRICA OVER THE E ATLC E OF 34W. THE FIRST VISIBLE SATELLITE IMAGES OF THE DAY CONTINUE TO SHOW A LARGE SURGE OF AFRICAN DUST OVER THE E ATLC S OF A LINE FROM JUST S OF THE STRAIT OF GIBRALTAR ALONG 32N18W 24N42W TO 22N55W WITH CLEARING S OF 16N E OF 35W. THE REMAINDER OF THE ATLC CONTINUES TO BE DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1031 MB HIGH CENTERED N OF THE REGION TO OVER THE N GULF OF MEXICO. $$ WALLACE