000 AXPZ20 KNHC 050946 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT OCT 05 2013 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS W ACROSS THE SW CARIBBEAN BETWEEN 10-11N FROM THE NW COAST OF COLOMBIA TO ACROSS CENTRAL COSTA RICA ALONG 10N...REACHING THE PACIFIC COAST OF COSTA RICA AT 10N85W...THEN CONTINUES W-NW TO THROUGH AN EMBEDDED 1009 MB SURFACE LOW PRESSURE AT 13N113W. THE MONSOON TROUGH THEN CONTINUES SW TO 10N128W WHERE SCATTEROMETER DATA INDICATE A TRANSITION TO AN ITCZ AXIS...WHICH IN TURN CONTINUES WESTWARD TO BEYOND 09N140W. SCATTERED CONVECTION IS ALONG THE COAST OF COLOMBIA WITHIN 75 NM OF 04N78W. SIMILAR CONVECTION IS NOTED WELL S OF THE MONSOON TROUGH AXIS WITHIN 30 NM OF 07.5N89.5W. SCATTERED MODERATE ISOLATED STRONG CONVECTION...ASSOCIATED WITH THE MONSOON TROUGH AND ITS EMBEDDED SURFACE LOW...IS OBSERVED WITHIN 120 NM EITHER SIDE OF A LINE FROM 10N112W TO 17N114W... AND WITHIN 45 NM EITHER SIDE OF A LINE FROM 11N113W TO 15N118W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 45 NM OF 15.5N122W...AND ALONG THE ITCZ WITHIN 90 NM EITHER SIDE OF A LINE FROM 10N128W TO 08N138W. ISOLATED MODERATE TO OCCASIONALLY STRONG CONVECTION IS NOTED WELL N OF THE MONSOON TROUGH WITHIN 240 NM OF THE COAST OF CENTRAL AMERICA FROM 87-100W. ...DISCUSSION... A LONGWAVE UPPER TROUGH IS OVER WESTERN CONUS CONTINUING SW INTO THE DISCUSSION AREA FROM 32N114W TO 32N125W...THEN THROUGH A PAIR OF UPPER CYCLONES AT 28N130W AND 23N137W...THEN THE UPPER TROUGH TURNS SE THROUGH UPPER CYCLONES OVER THE DEEP TROPICS AT 10N129W AND 04N120W. THIS UPPER TROUGH...AND SERIES OF EMBEDDED UPPER CYCLONES...EFFECTIVELY SEPARATES THE UPPER FLOW OVER THE DISCUSSION AREA. W OF THESE TROUGHS IS AN A UPPER ANTICYCLONE NOTED JUST N OF THE AREA AT 33N135W. AN UPPER RIDGE EXTENDS E INTO THE AREA ALONG 13N FROM 140-137W...WITH WEAK UPPER DIFFLUENCE NOTED OVER THE PREVIOUSLY DESCRIBED ITCZ...AND SEEMS TO HAVE ENHANCED CONVECTION EARLIER...WITH SOME OF THE DEBRIS MOISTURE NOW ADVECTED N WITHIN 90 NM OF A LINE FROM 12N131W TO 22N127W. OTHERWISE THE UPPER LEVELS APPEAR VERY DRY W OF A LINE FROM 32N100W TO 24N124W TO 17N140W. AN UPPER ANTICYCLONE IS QUASI-STATIONARY OVER OLD MEXICO AT 23N106W WITH AN UPPER RIDGE EXTENDING SW TO A CREST OVER THE DEEP TROPICAL PACIFIC AT 12N130W. UPPER DIFFLUENCE ALONG THE SW PERIPHERY OF THIS RIDGE HAS ENHANCED THE MONSOON TROUGH CONVECTION PREVIOUSLY MENTIONED BETWEEN 110-122W. THE RESULTANT UPPER DEBRIS MOISTURE IS SPREADING NW WITHIN THE UPPER RIDGE TO NEAR 23N120W. AN UPPER TROUGH EXTENDS SW FROM THE N-CENTRAL GULF OF MEXICO ACROSS CENTRAL MEXICO ALONG 22N98W TO OVER THE PACIFIC NEAR 16N108W AND SEPARATES THE UPPER FLOW ASSOCIATED WITH THE ANTICYCLONE AT 23N106W FROM THE ANTICYCLONIC FLOW ASSOCIATED WITH ANOTHER UPPER ANTICYCLONE OVER THE BAY OF CAMPECHE NEAR 19N92W...WITH ITS ANTICYCLONIC ENVELOPE EXTENDING S ACROSS THE TROPICAL E-PACIFIC TO THE N OF 08N BETWEEN 85-102W. THE ASSOCIATED UPPER DIFFLUENCE ENHANCED CONVECTION OVER CENTRAL AMERICA LATE FRI...WITH REMNANTS OF THE CONVECTION STILL DISSIPATING OVER THE E PORTION OF THE DISCUSSION AREA AS PREVIOUSLY DESCRIBED. DENSE DEBRIS MOISTURE IS ADVECTED S COVERING THE DISCUSSION AREA TO THE N OF 05N AND E OF 95W. ELSEWHERE AT THE SURFACE...A RIDGE EXTENDS FROM 32N135W TO 20N108W. ALTHOUGH THE NORTHERLY WINDS E OF THE RIDGE AXIS HAVE DIMINISHED TO 5-10 KT ACROSS THE DISCUSSION AREA WATERS...LONG PERIOD N SWELLS CONTINUE TO MERGE WITH CROSS EQUATORIAL LONG PERIOD SOUTHERLY SWELL...RESULTING IN COMBINED SEAS OF 6-8 FT ACROSS THE DISCUSSION AREA N OF 20N BETWEEN 115-140W. THE N SWELLS WILL SUBSIDE TODAY WITH COMBINED SEAS OF 5-6 FT BY THIS EVENING. A SURFACE LOW IS EMBEDDED IN THE MONSOON TROUGH NEAR 13N113W. CURRENTLY NE WINDS AT 15-20 KT ARE OBSERVED WITHIN 240 NM OVER THE NW QUADRANT...AND SE WINDS AT 15 KT ARE OBSERVED WITHIN 420 NM OVER THE SE SEMICIRCLE OF CENTER. SEAS IN THESE AREAS ARE 6-8 FT PRIMARILY DUE TO MIXING NW AND LONG PERIOD CROSS-EQUATORIAL SE SWELL. THE LOW IS FORECAST TO MOVE SLOWLY W TO NEAR 13N116W LATE TONIGHT...AND NEAR 13N120W LATE SUN NIGHT WITH WINDS DIMINISHING TO 10-15 KT AND SEAS SUBSIDING BELOW 8 FT BY SUNRISE MON. GULF OF CALIFORNIA...NW 20-30 KT WINDS...WITH SEAS 5-8 FT...ARE OCCURRING ACROSS THE OPEN FETCH WATERS N OF 29N. ALTHOUGH THE GRADIENT WILL RELAX SOME LATER TODAY...NW 20-25 KT CONDITIONS WILL SPREAD S ACROSS THE GULF WATERS N OF 25N LATE TONIGHT. THE GRADIENT WILL FURTHER WEAKEN ON SUN...WITH WINDS DIMINISHING TO 10-15 KT ACROSS THE ENTIRE GULF OF CALIFORNIA BY SUNRISE MON. SEAS WILL GRADUALLY SUBSIDE TO 2 FT OR LESS LATE MON. GULF OF TEHUANTEPEC...LIGHT AND VARIABLE WINDS ARE EXPECTED TO CONTINUE ACROSS THE TEHUANTEPEC AREA THROUGH SUN EVENING. NORTHERLY 15-20 KT DRAINAGE FLOW IS EXPECTED TO OCCUR ACROSS THE GULF OF TEHUANTEPEC WATERS LATE EACH NIGHT BEGINNING ON SUN NIGHT. GUIDANCE IS SUGGESTING THE DRAINAGE FLOW WILL INCREASE TO 20-25 KT LATE WED NIGHT. NELSON