000 AXNT20 KNHC 300557 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU JUL 30 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 31W S OF 24N MOVING W NEAR 10-15 KT. SATELLITE IMAGERY AND SATELLITE DERIVED WINDS INDICATE A BROAD LOW TO MID-LEVEL CYCLONIC FLOW IN THE VICINITY OF THE WAVE AXIS. THIS WAVE ALSO EXHIBITS A HIGH AMPLITUDE DEEP LAYER MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY...WHILE BEING SURROUNDED BY SAHARAN DUST...SCATTERED MODERATE CONVECTION REMAINS EMBEDDED WITHIN THE ITCZ AXIS AND IS FROM 8N-13N BETWEEN 25W-39W. A TROPICAL WAVE IS ALONG 61W S OF 18N MOVING W NEAR 20 KT. THIS WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. NO SIGNIFICANT DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THIS WAVE...HOWEVER...SCATTERED SHOWERS ARE MOVING ACROSS THE LESSER ANTILLES AND SE CARIBBEAN FROM 10N-16N BETWEEN 58W-66W. A TROPICAL WAVE IS ALONG 90W S OF 21N MOVING W NEAR 25 KT. THIS WAVE LIES IN A BROAD AREA OF DEEP LAYER MOISTURE OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY ACROSS CENTRAL AMERICA BECOMING MORE BROAD IN COVERAGE ACROSS THE E PACIFIC REGION. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 12N-17N BETWEEN 88W-93W. MORE WIDELY SCATTERED SHOWERS COVER THE NW CARIBBEAN AND YUCATAN PENINSULA S OF 22N BETWEEN 85W-92W. THIS CONVECTION IS FURTHER ENHANCED BY UPPER LEVEL RIDGING AND THUS UPPER LEVEL DIFFLUENCE ACROSS CENTRAL AMERICA. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N16W 11N20W 14N28W 13N33W 9N45W 12N59W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 8N-13N BETWEEN 17W-39W. ...DISCUSSION... GULF OF MEXICO... FAIRLY TRANQUIL WEATHER DOMINATES ACROSS MUCH OF THE GULF OF MEXICO AS AN UPPER LEVEL ANTICYCLONE IS CENTERED IN THE CENTRAL GULF NEAR 25N86W. THIS UPPER LEVEL FEATURE ALONG WITH A SURFACE RIDGE OF HIGH PRESSURE EXTENDING FROM THE W ATLC WATERS ALONG 29N IS PROVIDING MOSTLY CLEAR SKIES AND S-SELY WIND OF 10 TO 15 KT ACROSS THE GULF W OF 86W. HOWEVER...UPPER LEVEL DIFFLUENCE ON THE ERN PERIPHERY OF THE UPPER LEVEL RIDGE IS GENERATING A FEW ISOLATED SHOWERS E OF 84W. MOSTLY CONVECTIVE DEBRIS CLOUDINESS FROM EARLIER ACTIVITY IS ACROSS THE FLORIDA PENINSULA THIS EVENING. THE OTHER AREA TO NOTE ACROSS THE GULF IS THE TROPICAL WAVE ALONG 90W THAT IS BRINGING ISOLATED SHOWERS TO THE YUCATAN CHANNEL S OF 23N AND AREAS W TO 92W INCLUDING THE YUCATAN PENINSULA AND ERN BAY OF CAMPECHE. CARIBBEAN SEA... NORTHERLY UPPER LEVEL WINDS PREVAIL ACROSS MUCH OF THE CARIBBEAN BASIN AS AN UPPER LEVEL RIDGE EXTENDS FROM AN UPPER LEVEL ANTICYCLONE CENTERED OVER THE ERN GULF OF MEXICO. THE NLY WINDS ALOFT ARE KEEPING THE MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE DRY AND FAIRLY STABLE. HOWEVER...A TROPICAL WAVE ALONG 61W IS IMPACTING THE FAR ERN CARIBBEAN AND LESSER ANTILLES WITH INCREASED LOW-LEVEL MOISTURE AND SCATTERED SHOWERS OBSERVED S OF 16N BETWEEN 58W-66W. ACROSS THE WRN CARIBBEAN...THE TROPICAL WAVE ALONG 90W AND AN UPPER LEVEL DIFFLUENT PATTERN IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS FROM 11N-22N W OF 82W...INCLUDING THE GULF OF HONDURAS AND PORTIONS OF CENTRAL AMERICA. S OF 11N...SCATTERED SHOWERS AND TSTMS ARE OCCURRING BETWEEN 74W-86W DUE TO UPPER LEVEL DIFFLUENCE AND THE PROXIMITY OF THE ITCZ AXIS ALONG 9N CROSSING PANAMA. FRESH TO STRONG TRADE WINDS ARE NOTED ACROSS MUCH OF THE CARIBBEAN WITH THE STRONGEST WINDS NEAR THE COAST OF COLOMBIA. ATLANTIC OCEAN... A SHORTWAVE UPPER LEVEL TROUGH ALONG THE MID-ATLC U.S. SEABOARD IS ENHANCING SCATTERED SHOWERS AND TSTMS OVER THE SW NORTH ATLC WATERS COVERING THE AREA FROM 27N TO BEYOND 32N E OF 76W. THIS ACTIVITY STRETCHES S WITHIN 90 NM OF THE ERN FLORIDA PENINSULA COAST TO 24N. ENHANCEMENT OF THIS CONVECTION IS DUE IN LARGE PART TO THE UPPER LEVEL DIFFLUENCE GENERATING ON THE ERN PERIPHERY OF THE UPPER LEVEL ANTICYCLONE CENTERED OVER THE ERN GULF OF MEXICO. THE REMAINDER OF THE ATLC IS DOMINATED BY DRY STABLE AIR AND A BROAD SURFACE RIDGE ANCHORED BY A 1026 MB HIGH NEAR 33N56W BRINGING GENERALLY FAIR WEATHER ACROSS THE BASIN... EXCEPT FOR AN AREA OF CLOUDINESS AND POSSIBLE ISOLATED SHOWERS N OF THE TROPICAL WAVE ALONG 31W FROM 21N-30N BETWEEN 24W-35W. $$ HUFFMAN