000 AXNT20 KNHC 091054 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT AUG 09 2008 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... A LOW AMPLITUDE TROPICAL WAVE IS ALONG 35W S OF 16N MOVING W NEAR 15-20 KT. 850 MB SATELLITE DERIVED VORTICITY AND THE MIMIC-TPW FROM CIMSS SUPPORT THE WAVE POSITION. A CYCLONIC TURNING IS OBSERVED ALONG THE WAVE AXIS NEAR 11N. SCATTERED MODERATE CONVECTION IS MAINLY AHEAD OF THE WAVE AND NEAR THE INTERSECTION OF THE WAVE AND THE ITCZ FROM 6N-9N BETWEEN 32W-40W. SCATTERED SHOWERS ARE N OF 10N BETWEEN 33W-40W. A HIGH AMPLITUDE TROPICAL WAVE IS ALONG 54W FROM 11N-25N MOVING W 15-20 KT. THE WAVE CONTINUES TO SHOW A WELL DEFINED INVERTED-V CURVATURE ON SATELLITE IMAGERY WITH SCATTERED SHOWERS WITHIN 90 NM OF THE WAVE AXIS FROM 15N-18N. THE SSMI-DERIVED TOTAL PRECIPITABLE WATER INDICATES A BAND OF MOISTURE EXTENDING NORTH-SOUTH ALONG THE WAVE AXIS. NO DEEP CONVECTION IS OBSERVED. A TROPICAL WAVE IS OVER THE EASTERN CARIBBEAN ALONG 66W/67W S OF 22N MOVING W NEAR 20 KT. THE INTERACTION OF THE WAVE WITH AN UPPER-LEVEL LOW LOCATED N OF THE LEEWARD ISLANDS NEAR 25N60W IS PRODUCING SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS THE NRN LEEWARD/VIRGIN ISLANDS AND PUERTO RICO. THIS AREA OF MOISTURE IS FORECAST BY THE COMPUTER MODELS TO MOVE WNW OF PUERTO RICO AND MOVE ACROSS HISPANIOLA DURING THE DAY ON SATURDAY. THE WAVE IS ALSO GENERATING SCATTERED SHOWER ACTIVITY OVER N CENTRAL VENEZUELA. A TROPICAL WAVE IS ALONG 85W S OF 20N MOVING W 10-15 KT. SCATTERED MODERATE CONVECTION IS ASSOCIATED WITH THE WAVE OVER THE GULF OF HONDURAS AND BELIZE FROM 15N-19N BETWEEN 84W-89W. SIMILAR CONVECTION IS ALONG THE COSTA RICA COAST FROM 9N-12N BETWEEN 82W-85W AND IS MOST LIKELY THE RESULT OF AN UPPER DIFFLUENT PATTERN. BROAD AREA OF DEEP LAYERED MOISTURE IS OBSERVED ON MIMIC-TPW PRODUCT COVERING THE WRN CARIBBEAN W OF 80W. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 11N14W 14N24W 11N33W 8N38W 11N50W 11N55W 10N64W. A LARGE CLUSTER OF MODERATE TO STRONG CONVECTION IS FROM 7N-14N BETWEEN 16W-22W. SCATTERED MODERATE CONVECTION IS FROM 6N-9N BETWEEN 32W-41W...AND FROM 7N-9N BETWEEN 50W-55W. ...DISCUSSION... GULF OF MEXICO... AN UPPER-LEVEL HIGH CENTERED OVER WEST TEXAS EXTENDS RIDGING OVER THE NWRN GULF WATERS N OF 23N WHILE A DEEP LAYERED TROUGH IS OVER THE EASTERN U.S. INTO THE NE GULF WATERS N OF 27N AND E OF 88W. AS OF 09/0900Z...THE ATTENDANT COLD FRONT EXTENDS FROM JACKSONVILLE FLORIDA TO THE FLORIDA BIG BEND WWD ALONG 28N TO NEAR PORT ARTHUR TEXAS. THE FRONT WILL CONTINUE MOVING SWD ACROSS THE N GULF WATERS TONIGHT SLOWLY DISSIPATING DURING THE WEEKEND. A SURFACE TROUGH IS SE OF THE COLD FRONT AND EXTENDS FROM GAINESVILLE FLORIDA INTO THE GULF NEAR 27N86W. MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS AND TSTMS ARE WITHIN 90 TO 120 NM S OF THE TROUGH ACROSS THE GULF...INCLUDING THE CENTRAL FLORIDA PENINSULA. STRONG SUBSIDENCE AND DRY AIR FOLLOW BEHIND THE FRONT ACROSS THE NE GULF N OF 28N. AN UPPER LEVEL LOW IS ACROSS THE WRN BAY OF CAMPECHE AND REMAINS A RATHER BENIGN UPPER FEATURE THIS MORNING. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF WEAK SURFACE RIDGING THAT EXTENDS FROM THE W ATLC WATERS ACROSS CUBA INTO THE CENTRAL GULF. RATHER LIGHT S-SW WINDS ARE ACROSS THE AREA S OF 27N AND W OF 93W. CARIBBEAN SEA... AN UPPER-LEVEL LOW IS SPINNING OVER THE CENTRAL BAHAMAS AND EXTENDS TROUGHING INTO THE NW CARIBBEAN. BROAD UPPER-LEVEL HIGHS ARE ACROSS THE CENTRAL AND ERN CARIBBEAN WITH ONE CENTER NEAR THE ABC ISLANDS AND ANOTHER CENTER ACROSS THE SW CARIBBEAN NEAR 11N79W. ANOTHER UPPER-LEVEL LOW IS N OF THE LEEWARD ISLANDS NEAR 25N60W. THE CYCLONIC FLOW ASSOCIATED WITH THIS UPPER LOW ENVELOPS THE FAR ERN CARIBBEAN. THE INTERACTION OF THIS LOW WITH THE TROPICAL WAVE ALONG 66W/67W IS GENERATING SCATTERED SHOWER ACTIVITY OVER THE NE CARIBBEAN. UPPER LEVEL DIFFLUENCE COUPLED WITH ANOTHER TROPICAL WAVE ALONG 85W IS SUPPORTING SCATTERED SHOWERS AND TSTMS OVER THE SW CARIBBEAN AND COSTA RICA/NICARAGUA FROM 8N-13N BETWEEN 76W-84W. MODERATE TO STRONG EASTERLY TRADE WINDS ARE BLOWING ACROSS THE BASIN WITH THE STRONGEST WINDS OFFSHORE OF THE NRN COLOMBIAN COAST. ATLANTIC OCEAN... SEVERAL UPPER-LEVEL LOWS ARE NOTED ACROSS THE DISCUSSION AREA ON WATER VAPOR IMAGERY. ONE UPPER LOW IS OVER THE CENTRAL BAHAMAS WITH ASSOCIATED TROUGHING N OF 18N BETWEEN 65W TO THE FLORIDA PENINSULA. IT IS PRODUCING AN AREA OF SCATTERED SHOWERS AND TSTMS FROM 24N-29N BETWEEN 65W-75W. SCATTERED SHOWERS AND TSTMS ARE ALSO ASSOCIATED WITH AFOREMENTIONED COLD FRONT DRAPED ACROSS NRN FLORIDA FROM 27N-32N BETWEEN 71W-80W. THE SECOND UPPER LOW IS N OF THE LEEWARD ISLANDS AND THE THIRD UPPER LOW IS OVER THE CENTRAL ATLC NEAR 28N44W. ANOTHER UPPER-LEVEL LOW IS OVER THE ERN ATLC NEAR 29N24W WITH A TROUGH EXTENDING SW TO ANOTHER UPPER LOW CENTERED NEAR 22N32W. IN BETWEEN...A PAIR OF UPPER-LEVEL HIGHS. THE MAIN ONE IS OVER THE TROPICS NEAR 19N45W AND THE OTHER OFF THE W AFRICAN COAST NEAR 20N18W. OTHERWISE.. THE ATLANTIC IS DOMINATED BY A PAIR OF SURFACE HIGHS. A 1024 MB HIGH IS LOCATED OVER THE AZORES AND ANOTHER 1024 MB HIGH IS CENTERED NEAR 33N48W. TIGHT PRESSURE GRADIENT BETWEEN THE ATLC RIDGE AND LOWER PRESSURE OVER NW AFRICA IS PRODUCING A SWATH OF NELY WINDS OF 20-25 KT BETWEEN THE MADEIRA/CANARY ISLANDS AND THE AFRICAN COAST. THE FRONTAL BOUNDARY OVER THE SE U.S. IS FORECAST TO REMAIN IN THE FAR NW PORTION OF THE W ATLC DURING THE DAY ON SATURDAY AND REMAIN N OF 29N. $$ HUFFMAN