000 AXNT20 KNHC 132339 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN AUG 13 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS NEAR THE CAPE VERDE ISLANDS ALONG 25W S OF 17N MOVING W NEAR 15 KT. BROAD LOW-MID LEVEL TURNING IS EVIDENT ON SATELLITE IMAGERY...BUT MOISTURE REMAINS VERY LIMITED WITH ONLY ISOLATED SHOWERS NEAR THE WAVE AXIS. MORE ACTIVITY IS LOCATED TO THE W OF THE ANALYZED AXIS IN THE ITCZ. TROPICAL WAVE IS APPROACHING THE LESSER ANTILLES ALONG 59W S OF 19N MOVING W 10-15 KT. A WEAK 1011 MB LOW IS LOCATED ALONG THE WAVE NEAR 13N. MID-LEVEL TURNING EXISTS AHEAD OF THE ANALYZED WAVE AXIS. OVERALL...THE ORGANIZATION OF THIS WAVE IS FAIR BUT SHOWERS AND TSTMS REMAIN MINIMAL. SOME SLOW DEVELOPMENT IS POSSIBLE OVER THE NEXT DAY OR TWO WITH THIS SYSTEM. TROPICAL WAVE IN THE WRN CARIBBEAN IS ALONG 85W/86W S OF 20N MOVING W 15-20 KT. THIS WAVE CONTINUES TO BE NOT VERY WELL DEFINED. PATCHES OF SCATTERED MODERATE CONVECTION LIE FROM THE SW CARIBBEAN THROUGH CENTRAL AMERICA AND INTO THE GULF OF HONDURAS. THIS IS LIKELY ENHANCED BY INSTABILITY AROUND THE BASE OF THE UPPER TROUGH IN THE REGION...ALONG WITH UPSLOPE FLOW OVER THE CENTRAL AMERICAN TERRAIN. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 13N15W 10N27W 9N48W TO VENEZUELA NEAR 10N65W. BESIDES FOR THE TROPICAL WAVES...CLUSTERS OF SCATTERED MODERATE CONVECTION LIE E OF 19W FROM 9N-14N LIKELY ASSOCIATED WITH THE NEXT TROPICAL WAVE. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 150 NM EITHER SIDE OF THE AXIS BETWEEN 28W-35W AND 45W-54W. ...DISCUSSION... GULF OF MEXICO... ANOTHER MAINLY QUIET WEATHER DAY IS UNDERWAY ACROSS THE GULF OF MEXICO DUE IN PART TO A 1019 MB SFC HIGH PARKED IN THE MIDDLE OF THE REGION NEAR 26N89W. SFC WINDS ARE LIGHT AND ANTICYCLONIC AROUND THE HIGH...THE STRONGEST WINDS BEING THE RETURN FLOW NEAR 15 KT IN THE EXTREME WRN GULF. THE ONLY UNSETTLED WEATHER EXISTS IN THE CORNERS OF THE REGION. A COLD FRONT EXTENDS FROM THE ATLC ACROSS CENTRAL FLORIDA THEN AS A DISSIPATING STATIONARY FRONT TO THE FL PANHANDLE. SCATTERED SHOWERS AND TSTMS HAVE FIRED UP THIS AFTERNOON AND EVENING NEAR THIS SFC BOUNDARY...NEARLY ALL OF THE ACTIVITY IS OVER LAND AREAS WHERE INSTABILITY IS GREATER. IN THE UPPER LEVELS...AN UPPER HIGH IS CENTERED OVER SOUTH/CENTRAL FLORIDA WITH ANOTHER UPPER HIGH OVER SRN MEXICO. AN UPPER LOW HAS MOVED WELL INLAND OVER NRN MEXICO NEAR 27N102W. ESSENTIALLY...DRY/STABLE AIR LIES ABOVE MUCH OF THE REGION E OF 93W. MID-HIGH LEVEL CLOUDINESS AND ISOLATED SHOWERS EXISTS W OF THERE. A SURGE OF MODERATE TO STRONG CONVECTION IS CURRENTLY OVER THE YUCATAN PENINSULA FROM 17N-22N BETWEEN 89W-91W MOVING INTO THE BAY OF CAMPECHE. THE BEST CHANCE OF RAIN OVER THE NEXT DAY OR TWO WILL CONTINUE TO BE IN THE ERN GULF NEAR THE TAIL END OF THE ATLC FRONTAL BOUNDARY AND IN THE BAY OF CAMPECHE ENHANCED BY THE APPROACHING TROPICAL WAVE. CARIBBEAN SEA... TWO TROPICAL WAVES ARE AFFECTING THE CARIBBEAN...ONE MOVING W OF THE AREA ALONG 85W/86W AND THE OTHER APPROACHING THE LESSER ANTILLES. FOR MORE DETAILS REFER TO THE TROPICAL WAVES SECTION. IN THE UPPER LEVELS...A TROUGH/RIDGE PATTERN IS ESTABLISHED...WITH THE UPPER TROUGH EXTENDING FROM THE ERN BAHAMAS TO THE SW CARIBBEAN SEA NEAR 14N81W. SOME UPPER DIFFLUENCE ON THE W SIDE OF THE TROUGH AIDED BY LIFTING FROM THE NEARBY TROPICAL WAVE IS PRODUCING PATCHES OF MODERATE CONVECTION OVER PORTIONS OF CENTRAL AMERICA...THE YUCATAN PENINSULA...CUBA AND DOTTED ACROSS THE NW CARIBBEAN SEA. ONLY SOME HIGH CLOUDINESS AND POSSIBLY A FEW SHOWERS ARE ON THE TYPICAL MOIST S AND E SIDE OF THE TROUGH BETWEEN 73W-78W. AN UPPER HIGH IS LOCATED CLOSE TO THE LEEWARD ISLANDS CENTERED NEAR 16N61W. DRY/STABLE AIR AND FAIR WEATHER DOMINATES MUCH OF THE ERN CARIBBEAN...EXCEPT FOR AN AREA OF DISORGANIZED SHOWERS ACROSS THE WINDWARD AND LEEWARD ISLANDS ASSOCIATED WITH THE APPROACHING TROPICAL WAVE. 15 TO 25 KT TRADE WIND FLOW DOMINATES WITH THE STRONGEST WINDS JUST NORTH OF THE COLOMBIAN COAST...AS THE S PORTION OF THE ATLC HIGH INTERACTS WITH LOWER PRESSURE OVER COLOMBIA. SHOWERS AND TSTMS ASSOCIATED WITH THE TROPICAL WAVE WILL MOVE THROUGH THE ERN CARIBBEAN ON MONDAY. ATLANTIC OCEAN... STRONG MID TO UPPER LEVEL TROUGH HAS PUSHED OFF THE U.S. EAST COAST WITH ITS SOUTHERN MOST PORTION EXTENDING SOUTH TO NEAR 30N NEAR THE GEORGIA/NE FLORIDA COAST. SURFACE HIGH PRESSURE AND DRY UPPER LEVEL AIR HAS BUILT INTO THE MID ATLANTIC STATES BRINGING VERY PLEASANT WEATHER. IN THE REGION OF CONFLUENCE BETWEEN THIS HIGH AND THE ATLC RIDGE TO ITS SOUTH LIES A COLD FRONT THAT EXTENDS FROM A 1008 MB LOW NEAR 34N57W TO A 1012 MB LOW NEAR 29N75W TO CENTRAL FLORIDA. ALTHOUGH THE ASSOCIATED SHOWER AND THUNDERSTORM ACTIVITY IS CURRENTLY POORLY ORGANIZED WITH THE 1012 MB LOW ALONG THE FRONT...THIS SYSTEM WILL BE MONITORED AS SOME SLOW DEVELOPMENT IS POSSIBLE. THERE ARE SEVERAL UPPER LEVEL FEATURES IN THE ATLC...NONE OF WHICH ARE GENERATING ANY ORGANIZED AREAS OF CLOUDINESS MUCH LESS SHOWERS. AN UPPER RIDGE AXIS EXTENDS EAST FROM CENTRAL FLORIDA TO NEAR 72W. AN UPPER TROUGH IS EXTENDING NE THROUGH CUBA AND THE BAHAMAS INTO THE ADJACENT WATERS. UPPER RIDGING DOMINATES THE AREA FROM 10N TO 32N BETWEEN 52W AND 68W. A FEW SMALL/BENIGN UPPER LOWS LIE E OF THIS AREA...NEAR 27N48W...26N35W AND THE LAST NEAR 15N33W. AN UPPER RIDGE STRETCHES FROM THE COAST OF W AFRICA OUT TO NEAR 35W WITH THE AXIS ALONG 20N. ESSENTIALLY...DRY STABLE AIR DOMINATES THE MAJORITY OF THE AREA. AT THE SFC...FAIR WEATHER UNDER HIGH PRES RIDGING IS THE THEME WITH THE RIDGE AXIS EXTENDING FROM A 1020 MB HIGH NEAR 27N32W TO ANOTHER 1020 MB NEAR 27N56W ACROSS THE BAHAMAS INTO THE GULF OF MEXICO. A WEAK 1016 MB LOW N OF THE AREA NEAR 35N29W HAS A SFC TROF WHICH EXTENDS TO 29N37W. THIS LOW IS EMBEDDED IN THE DRY ENVIRONMENT MENTIONED SQUEEZING OUT ONLY ISOLATED SHOWERS NEAR THE LOW AND TRAILING TROF. $$ CANGIALOSI