000 AXPZ20 KNHC 281535 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE AUG 28 2007 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...TROPICAL WAVES... TROPICAL WAVE ALONG 84W N OF 7N THROUGH COSTA RICA AND NICARAGUA IS MOVING W NEAR 15 KT. SMALL CLUSTERS OF MODERATE CONVECTION ARE NOTED NEAR THE WAVE OFF THE COSTA RICAN COAST FROM 6N-10N BETWEEN 82W-86W. HOWEVER...THE MAIN AREA OF CYCLONIC TURNING ASSOCIATED WITH THE WAVE IS OVER THE CARIBBEAN PORTION APPROACHING HONDURAS. THE CONVECTION S OF THE CENTRAL AMERICAN COAST MAY BE MORE ASSOCIATED WITH THE CONTINUED CONVERGENCE DOWNSTREAM FROM THE LONG FETCH OF MODERATE ONSHORE SW FLOW IN THE EPAC. TROPICAL WAVE PREVIOUSLY ALONG 95W WAS RELOCATED SLIGHTLY TO THE E TO 94W...ESTIMATED TO BE MOVING W NEAR 10 KT. THE RELOCATION WAS IN RESPONSE TO THE PERSISTENT...SLOW MOVING AREA OF LOW TO MID LEVEL CYCLONIC TURNING SSE OF THE GULF OF TEHUANTEPEC AND S OF GUATEMALA. ASSOCIATED SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 150 NM EITHER SIDE OF THE AXIS FROM 9N-14N. TROPICAL WAVE PREVIOUSLY ALONG 106W WAS DROPPED AS THE AREA OF CYCLONIC TURNING IN THE VICINITY HAS REMAINED QUASI-STATIONARY OVER THE LAST SEVERAL HOURS. HOWEVER...A 1005 MB LOW REMAINS IN THE VICINITY NEAR 17N106W. THIS...IN ADDITION TO DIFFLUENT FLOW ALOFT...IS ASSISTING IN THE NUMEROUS MODERATE CONVECTION OFF THE COAST OF MEXICO FROM 14N-24N BETWEEN 104W-110W. UPPER-LEVEL WINDS ARE MARGINALLY FAVORABLE FOR GRADUAL DEVELOPMENT OF THIS SYSTEM DURING THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY WEST-NORTHWESTWARD. ...ITCZ... AXIS IS CENTERED ALONG 10N84W 11N92W 16N100W 16N110W 11N123W 13N130W 12N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF LINE 4N77W 8N86W...WITHIN 120 NM EITHER SIDE OF LINE 13N90W 10N97W...AND FROM 13N TO 23N BETWEEN 103W AND 111W. SCATTERED MODERATE FROM 8N TO 13N BETWEEN 102W AND 115W AND FROM 10N TO 13N BETWEEN 132W AND 140W. ...DISCUSSION... E OF 115W... THE MAIN WEATHER AREAS IN THE FAR NE PAC ARE ASSOCIATED WITH THE TROPICAL WAVE S OF THE GULF OF TEHUANTEPEC ALONG 94W...AND THE 1005 MB LOW FURTHER W OFF OF MEXICO NEAR 17N106W. SEE TROPICAL WAVE SECTION ABOVE FOR MORE DETAILS. ON THE LARGE SCALE...THE SFC PATTERN IS DOMINATED BY BROAD TROUGHING WITH ABUNDANT MONSOON-LIKE SW FLOW S OF THE COASTS OF MEXICO AND CENTRAL AMERICA...FROM THE EQUATOR TO NEAR 13N. LOCAL WIND WAVES ASSOCIATED WITH THIS PATTERN WILL MIX WITH A COUPLE PULSES OF MODERATE LONGER PERIOD S/SW SWELL OVER THE NEXT SEVERAL DAYS...WHICH WILL MAINLY BE AN IMPACT NEAR SHORE UPON SHOALING. AN UPPER TROUGH EXTENDS N-S ROUGHLY ALONG 85W FROM HONDURAS TO WRN COSTA RICA. AN UPPER ANTICYCLONE IS CENTERED OVER THE WRN GULF OF MEXICO...WITH ANOTHER UPPER HIGH OVER NW MEXICO NEAR 29N110W. STRONG E TO NE UPPER FLOW BETWEEN THESE FEATURES IS SHEARING THE AFOREMENTIONED CONVECTION NEAR THE ITCZ TO THE SW. UPPER FLOW BENDS MORE SE OFF THE COAST OF BAJA...WHICH IS PROMOTING UPPER DIFFLUENCE SUPPORTING THE CONVECTION OFFSHORE ACAPULCO THROUGH MANZANILLO. W OF 115W... FAIRLY WEAK SFC RIDGING DOMINATES THE AREA N OF 18N...ANCHORED BY A 1026 MB HIGH NEAR 37N141W. THIS IS PRODUCING LIGHT TO MODERATE TRADES ACROSS THE VICINITY AND IS GENERALLY EXPECTED TO PERSIST OVER THE NEXT COUPLE OF DAYS. A WEAK 1012 MB LOW CONTINUES TO MEANDER NEAR 16N130W...BUT HAS NO DEEP CONVECTION ASSOCIATED WITH IT AND IS EXPECTED TO DISSIPATE THROUGH WED. UPPER LOW IS CENTERED 22N125W WITH UPPER ANTICYCLONE TO THE W NEAR 24N135W. VERY DRY/STABLE AIR IS ROTATING AROUND THESE FEATURES AND IS SUPPRESSING CONVECTION OVER MUCH OF THE AREA. $$ WILLIS