000 AXNT20 KNHC 131028 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON AUG 13 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. ...SPECIAL FEATURE... A 1007 MB LOW...ASSOCIATED WITH A TROPICAL WAVE ALONG 28W/29W S OF 18N...IS LOCATED SW OF THE CAPE VERDE ISLANDS NEAR 12N MOVING W 15 KT. THE FIRST VISIBLE SATELLITE IMAGERY SHOWS A LOW LEVEL CIRCULATION IS UNDER THE EASTERN EDGE OF THE CONVECTION. SCATTERED STRONG CONVECTION IS FROM 10N-14N BETWEEN 30W-34W. . ...TROPICAL WAVES... A 1009 MB LOW IS ALONG THE COAST OF W AFRICA NEAR 15N17W AND IS MOVING W 15-20 KT. THIS LOW IS ASSOCIATED WITH THE NEXT TROPICAL WAVE EMERGING INTO THE ATLC. SCATTERED MODERATE CONVECTION IS FROM 13N-16N E OF 21W TO THE COAST OF AFRICA. TROPICAL WAVE IS ALONG 38W S OF 15N MOVING W 10-15 KT. THIS IS A WEAK LOW AMPLITUDE WAVE. THE CONVECTION AND UPPER LEVEL OUTFLOW WITH THE ABOVE WAVE/LOW CONTINUES TO APPROACH THE INVERTED-V CURVATURE WITH THIS WAVE. NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 46W S OF 18N MOVING W 10-15 KT. WEAK LOW LEVEL INVERTED-V CURVATURE IS NOTED WITH A BETTER DEFINED MID LEVEL ROTATION EMBEDDED WITHIN THE ITCZ. SCATTERED SHOWERS ARE FROM 7N-12N BETWEEN 45W-49W. TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN ALONG 80W S OF 18N MOVING W 15-20 KT. WAVE SIGNATURE IS MASKED BY UPPER LEVEL RIDGE WITH ANY SHOWER ACTIVITY/CONVECTION ASSOCIATED WITH UPPER LEVEL FEATURES. TROPICAL WAVE IS OVER THE YUCATAN PENINSULA ALONG 89W/90W S OF 23N MOVING W 15-20 KT. WAVE SIGNATURE IS MASKED BY AN UPPER LEVEL TROUGH WITH ANY SHOWER ACTIVITY/CONVECTION ASSOCIATED WITH UPPER LEVEL FEATURES. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 14N20W 12N32W 8N41W 7N60W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 4N-9N BETWEEN 27W-34W. DISCUSSION... GULF OF MEXICO... AN UPPER LOW DOMINATES THE GULF THIS MORNING CENTERED NEAR 25N87W EXTENDING AN UPPER TROUGH S TO OVER THE YUCATAN PENINSULA. SCATTERED SHOWERS/THUNDERSTORMS ARE MOSTLY S OF 27N E OF 85W TO OVER S FLORIDA AND THE THROUGH THE FLORIDA STRAITS AND IN THE W GULF WITHIN A 75 NM RADIUS OF 25N94W. SOME ISOLATED SHOWERS/THUNDERSTORMS DOT THE GULF WITHIN 125 NM OF A LINE FROM 29N85W INTO THE BAY OF CAMPECHE AND S MEXICO NEAR 18N95W. CARIBBEAN SEA... AN UPPER RIDGE EXTENDS FROM HONDURAS NEAR 15N84W N TO ACROSS CENTRAL CUBA NEAR 22N80W WITH ENOUGH DIFFLUENCE AND TROPICAL MOISTURE TO GENERATE CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION N OF 12N FROM 78W-82W AND N OF 18N TO OVER CUBA AND THROUGH THE YUCATAN CHANNEL BETWEEN 82W-86W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS COVER THE REMAINDER OF THE W CARIBBEAN W OF 75W. AN UPPER TROUGH FROM THE CENTRAL ATLC EXTENDS OVER THE E CARIBBEAN THROUGH AN UPPER LOW OVER PUERTO RICO/VIRGIN ISLANDS SW TO 12N74W. THIS IS KEEPING THE E CARIBBEAN E OF 74W DRY THIS MORNING. ATLANTIC OCEAN... AN UPPER RIDGE EXTENDS INTO THE W ATLC ACROSS CENTRAL CUBA TO NEAR 32N71W. A DEEP LAYERED TROUGH IS DIPPING S TO 30N AND A STATIONARY FRONTAL BOUNDARY IS ALONG THE N PERIPHERY OF THE REGION. THIS IS COMBINING TO PRODUCE SCATTERED SHOWERS AND WIDELY ISOLATED THUNDERSTORMS N OF A LINE FROM CUBA NEAR 22N77W ALONG 27N71W TO BEYOND 32N57W. AN UPPER TROUGH IS OVER THE CENTRAL ATLC EXTENDING THROUGH 32N47W TO AN UPPER LOW NEAR 27N51W TO A SECOND UPPER LOW OVER PUERTO RICO/VIRGIN ISLANDS AND INTO THE E CARIBBEAN GENERATING A SMALL AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 22N-24N BETWEEN 61W-63W. AN UPPER RIDGE DOMINATES THE E ATLC EXTENDING E/W FROM OVER AFRICA NEAR 26N14W TO NEAR 22N42W. A WEAK UPPER LOW IS IN THE NE ATLC NW OF THE CANARY ISLANDS NEAR 31N20W. DRY STABLE AIR COVERS THE ATLC E OF 55W WITH A BROAD SURFACE RIDGE EXTENDING FROM A 1023 MB HIGH S OF THE AZORES NEAR 34N30W SW ALONG 27N60W TO OVER THE BAHAMAS NEAR 26N77W. $$ WALLACE