000 AXPZ20 KNHC 290239 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SUN SEP 29 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 09N79W TO LOW PRES NEAR 12N96W TO 09N99W...THEN RESUMES FROM LOW PRES NEAR 18N108W TO LOW PRES NEAR 12N114W TO 10N130W. THE ITCZ AXIS EXTENDS FROM 10N130W TO BEYOND 10N140W. SCATTERED MODERATE CONVECTION IS WITHIN 150 NM S OF THE MONSOON TROUGH E OF 83W...FROM 07N TO 09N BETWEEN 87W AND 89W...AND ALSO FROM 16N TO 19N BETWEEN 105W AND 108W. ...DISCUSSION... AN UPPER LEVEL CYCLONIC CIRCULATION IS NEAR 26N134W AT THE SW TAIL OF AN UPPER TROUGH WHICH EXTENDS N-NE OF THE AREA THROUGH 32N130W. A NEARLY STATIONARY BROAD UPPER LEVEL ANTICYCLONE IS CENTERED OVER THE SOUTHERN PORTION OF THE BAJA CALIFORNIA PENINSULA NEAR 24N114W. DRY AND STABLE AIR IS ACROSS THE WATERS N OF 20N W OF 110W...AND FROM 10N TO 20N W OF 128W. CONVECTIVE DEBRIS IS BEING ADVECTED FROM THE NE-E TO THE SW-W ACROSS THE EASTERN HALF OF THE WATERS AROUND THE BACK SIDE OF THIS UPPER ANTICYCLONE WHERE EASTERLY FLOW DOMINATE THE WATERS. A LARGE UPPER LEVEL CYCLONIC CIRCULATION IS OVER THE SW WATERS NEAR 02N138W WHICH IS CONTINUING UPPER LEVEL EASTERLY FLOW OVER THE SW PORTION OF THE DISCUSSION AREA. AT THE SURFACE...1024 MB HIGH PRES IS NEAR 34N145W WITH A RIDGE AXIS EXTENDING SE TO NEAR 22N114W. LIGHT TO MODERATE WINDS AND 5- 7 FT SEAS ARE PREVELANT ACROSS THE MAJORITY OF THE WATERS N OF 10N W OF 110W. A COLD FRONT IS TO THE NW-N OF THE SURFACE HIGH APPROACHING THE U.S. PACIFIC NW. THE PRIMARY ENERGY ASSOCIATED WITH THIS FRONT IS EXPECTED TO REMAIN N OF 30N...HOWEVER LARGE NW SWELL OF 8-13 FT WILL BREACH THE DISCUSSION WATERS BY SUN NIGHT. THE NW SWELL WILL CONTINUE TO PROPAGATE TO THE SE WITH HEIGHTS OF 8-13 FT COVERING THE AREA N OF A LINE FROM 30N117W TO 28N120W TO 23N130W TO 22N140W BY MON EVENING. 1011 MB LOW PRES IS EMBEDDED IN THE MONSOON TROUGH S-SW OF THE GULF OF TEHUANTEPEC AREA NEAR 12N96W. MODERATE TO FRESH WINDS ARE IN THE VICINITY OF THE LOW...WHILE 8-9 FT SEAS ARE FROM 04N TO 08N BETWEEN 93W AND 99W AS INDICATED BY A RECENT CRYOSAT ALTIMETER PASS. THESE MARINE CONDITIONS WILL PERSIST THROUGH SUN AFTERNOON AS THE LOW SLOWLY MOVES TO THE WSW...THEN WILL DIMINISH/SUBSIDE BY SUN EVENING AS THE LOW BECOMES ILL-DEFINED. WEAK AND BROAD 1011 MB SURFACE LOW PRES IS SW OF THE W CENTRAL COAST OF MEXICO NEAR 18N108W. ASSOCIATED CONVECTION HAS INCREASED SLIGHTLY DURING THE PAST SEVERAL HOURS ALTHOUGH IT REMAINS QUITE DISORGANIZED. ASSOCIATED WINDS ARE ONLY LIGHT TO MODERATE WITH 4-6 FT SEAS. NO DEVELOPMENT OF THIS LOW IS ANTICIPATED DURING THE NEXT 24-48 HOURS. ANOTHER 1011 MB LOW PRES IS EMBEDDED IN THE MONSOON TROUGH NEAR 12N114W. MODERATE TO FRESH WINDS WERE INDICATED BY RECENT ASCAT AND OSCAT PASSES...WITH 8-9 FT SEAS OCCURRING WITHIN 240 NM IN THE SE AND S QUADRANTS OF THE LOW. THIS LOW IS FORECAST TO WEAKEN WHILE DRIFTING E WITH ASSOCIATED WINDS AND SEAS DIMINISHING/SUBSIDING BY SUN AFTERNOON. $$ LEWITSKY