000 AXNT20 KNHC 301102 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON JUL 30 2012 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...TROPICAL WAVES... TROPICAL WAVE E OF THE LESSER ANTILLES EXTENDS FROM 21N57W TO 10N59W MOVING W 15-20 KT. WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 300 NM W OF THE WAVE BETWEEN 11N-19N INCLUDING THE LESSER ANTILLES. ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 250 NM E OF THE WAVE BETWEEN 14N-18N. TROPICAL WAVE IN THE CENTRAL CARIBBEAN EXTENDS FROM 18N78W TO 11N78W MOVING W 20-25 KT. WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE WEAK SURGE OF MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. NO ASSOCIATED SHOWERS/DEEP CONVECTION. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 12N15W EXTENDING ALONG 9N26W THROUGH A 1010 MB LOW NEAR 9N34W TO 6N43W WHERE THE ITCZ CONTINUES ALONG 6N50W TO INLAND OVER SOUTH AMERICA NEAR 6N58W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 6N-12N BETWEEN 22W-40W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 6N-10N BETWEEN 40W-46W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE COVERS THE N GULF N OF 25N AND IS ANCHORED OVER THE CENTRAL PLAIN STATES. A PAIR OF UPPER LOWS DOMINATE THE REMAINDER OF THE GULF WITH ONE CENTERED IN THE STRAITS OF FLORIDA ALONG THE N COAST OF CUBA NEAR 23N81W AND EXTENDING AN UPPER TROUGH W TO A SECOND UPPER LOW JUST INLAND OVER MEXICO NEAR 22N99W. THIS IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS IN THE BAY OF CAMPECHE WITHIN 60 NM ALONG THE COAST BETWEEN 91W-94W. ISOLATED SHOWERS/THUNDERSTORMS ARE POSSIBLE OVER THE N GULF N OF 24N BETWEEN 84W-90W. A SURFACE RIDGE EXTENDS FROM W ATLC ACROSS CENTRAL FLORIDA THROUGH A 1018 MB HIGH NEAR 27N85W TO GULF W COAST NEAR THE TEXAS/MEXICO BORDER LEAVING THE REMAINDER OF THE GULF WITH FAIR WEATHER THIS MORNING. SURFACE RIDGE WILL PERSIST THROUGH FRI. TROPICAL WAVE WILL MOVE THROUGH THE BAY OF CAMPECHE TUE THROUGH THU AND W OF AREA FRI. CARIBBEAN SEA... THE UPPER LOW CENTERED IN THE STRAITS OF FLORIDA/COAST OF CUBA COVERS THE W CARIBBEAN W OF 74W GENERATING CLUSTERS OF ISOLATED SHOWERS/THUNDERSTORMS N OF 15N W OF 78W. A NARROW UPPER RIDGE EXTENDS FROM COLOMBIA NEAR 10N75W TO NICARAGUA NEAR 13N84W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA ACROSS THE SW CARIBBEAN ALONG 10N80W INTO THE E PACIFIC REGION OVER COSTA RICA NEAR 11N84W GENERATING SCATTERED SHOWERS/THUNDERSTORMS THAT ARE BEING DRAWN NW DUE TO THE UPPER FLOW AND COVER THE SW CARIBBEAN SW OF A LINE FROM 15N83W TO COLOMBIA NEAR 10N75W. THE ACTIVITY OVER E CARIBBEAN AND THE LESSER ANTILLES IS DUE TO THE TROPICAL WAVE JUST E OF THE ISLANDS LEAVING THE REMAINDER OF THE CARIBBEAN WITH FAIR WEATHER THIS MORNING. CENTRAL CARIBBEAN TROPICAL WAVE WILL MOVE THROUGH W CARIBBEAN LATER TODAY AND TUE THEN W OF BASIN WED. SECOND STRONGER TROPICAL WAVE E OF THE LESSER ANTILLES WILL MOVE INTO E CARIBBEAN TONIGHT PASSING THROUGH CENTRAL CARIBBEAN LATE TUE AND WED THEN THROUGH W CARIBBEAN THU AND FRI. ATLANTIC OCEAN... AN UPPER TROUGH IS OVER THE NW ATLC DRAPING A FRONTAL BOUNDARY INLAND OVER THE SE CONUS GENERATING SCATTERED SHOWERS/ THUNDERSTORMS N OF 30N BETWEEN 78W-80W AND N OF 31N W OF 74W TO INLAND OVER SOUTH CAROLINA. TO THE E IS A LARGE UPPER RIDGE N OF 27N. AN UPPER TROUGH EXTENDS FROM THE E ATLC NEAR 32N28W THROUGH A SERIES OF UPPER LOWS CENTERED NEAR 27N41W...25N69W...TO THE UPPER LOWS IN THE GULF OF MEXICO. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 22N-26N BETWEEN 66W-73W. ISOLATED SHOWERS/THUNDERSTORMS ARE IN THE STRAITS OF FLORIDA FROM 23N-25N BETWEEN 79W-83W INCLUDING THE FLORIDA KEYS. SCATTERED SHOWERS ARE FROM 24N-32N BETWEEN 43W-50W. A SURFACE RIDGE EXTENDS FROM A 1021 MB HIGH IN THE CENTRAL ATLC NEAR 31N56W ACROSS CENTRAL FLORIDA INTO THE GULF OF MEXICO. A SURFACE RIDGE DOMINATES THE E ATLC WITH A WEAK 1018 MB LOW BETWEEN THE RIDGES CENTERED NEAR 31N44W. THE SURFACE RIDGE WILL LIFT N TO 28N LATER TODAY AND ALONG 29N TUE THEN SHIFT BACK S AGAIN ON WED AND THU. THE TROPICAL WAVE E OF THE LESSER ANTILLES WILL MOVE INTO THE E CARIBBEAN TONIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW