000 AXPZ20 KNHC 120251 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON AUG 12 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 0200 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM COLOMBIA NEAR 09N74W TO 11.5N81W TO 09N90W TO LOW PRES NEAR 09.5N107W 1010 MB...WHERE IT HAS FRACTURED. TROUGH RESUMES NEAR 16N120W TO LOW PRES NEAR 13.5N123.5W 1008 MB TO 11N130W TO 13.5N134W TO LOW PRES NEAR 12N138W 1008 MB TO 11N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED FROM 05N TO 10N E OF 93W. SCATTERED MODERATE CONVECTION NOTED WITHIN 150 NM S OF TROUGH BETWEEN 123W AND 130W. SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED WITHIN 90 NM EITHER SIDE OF TROUGH W OF 134W. SCATTERED MODERATE TO STRONG CONVECTION NOTED WITHIN 150 NM W QUADRANT OF LOW PRES NEAR 13.5N123.5W. ...DISCUSSION... WATER VAPOR IMAGERY SHOWS UPPER RIDGE STRETCHING ACROSS AREA HAS REALIGNED IN PAST 24 HOURS...NOW MORE NE TO SW FROM ELONGATED UPPER ANTICYCLONE NEAR 29N107W TO 18N143W. BROAD UPPER LEVEL SW TO W FLOW IS SEEN N OF THE RIDGE...AND VERY DRY AND STABLE CONDITIONS PREVAIL WITHIN THE RIDGE AND TO ITS NW. E TO NE WINDS ALOFT GENERALLY PREVAIL ACROSS THE REMAINDER OF THE AREA S AND SE OF THE RIDGE...CONTINUING TO PRODUCE A GENERALLY LIGHTLY SHEARED ENVIRONMENT. A TUTT LOW THAT HAS SHIFTED WWD ACROSS THE TROPICAL EPAC DURING THE PAST SEVERAL DAYS HAS WEAKENED TO AN OPEN TROUGH NOW ALONG ABOUT 120W AND CONTINUES TO SHIFT W. CONVERGENCE CONTINUES ACROSS NW PORTIONS OF THIS UPPER LEVEL WAVE...AND ACROSS THE NE PORTIONS OF THE SURFACE LOW NEAR 13.5N123.5W...AND IS CONTRIBUTING TO AN UNFAVORABLE ENVIRONMENT FOR SHORT TERM DEVELOPMENT OF THE LOW. AT THE SURFACE...A WEAK 1021 MB HIGH IS ANALYZED NEAR 31N138W WITH A RIDGE EXTENDING SE TO NEAR 23N113W. THE WEAK PRES GRADIENT BETWEEN THE HIGH AND PERSISTENT LOW PRES ALONG THE SIERRA MADRES OCCIDENTALES HAS BEEN PRODUCING NNW WINDS 15-20 KT ALONG AND OFFSHORE OF THE W COAST OF BAJA CALIFORNIA TO ABOUT 117W...WHERE WAVE MODEL GUIDANCE AND A FEW SHIP OBSERVATIONS FROM THE PAST 24 HOURS INDICATED PEAK SEAS ARE 5-6 FT. THESE CONDITIONS ARE FORECAST TO GENERALLY PREVAIL OVER THE NEXT 24-48 HOURS...WITH BRIEF PULSING OF WINDS TO AROUND 20 KT WITH HIGHER GUSTS AND SEAS BRIEFLY 6-7 FT EXPECTED EACH OF THE NEXT FEW EVENINGS. THE HIGH IS FORECAST TO WEAKEN SLIGHTLY AS IT SHIFTS SLOWLY E DURING THE NEXT 24 HOURS. THE PRES GRADIENT BETWEEN THE HIGH AND THE MONSOON TROUGH TO THE S IS MODEST AT BEST...AND IS AIDING IN PRODUCING SMALL AREAS OF FRESH NE TRADES TO 25 KT TO THE N AND NW OF TWO LOW PRES CENTERS EMBEDDED ALONG THE MONSOON TROUGH...MENTIONED ABOVE. THESE TWO LOW PRES CENTERS WILL SHIFT GENERALLY W DURING THE NEXT 48 HOURS AND MAINTAIN ZONES OF FRESH NE TO E TRADES ACROSS THE N AND NW SEMICIRCLES...WHERE PEAK SEAS WILL PERSIST NEAR 8-10 FT. ALTHOUGH GLOBAL MODELS HAD BEEN SUGGESTING FOR THE PAST FEW DAYS THAT THE LOW ALONG 123.5W HAD POTENTIAL FOR INTENSIFICATION TO A TROPICAL CYCLONE...ATMOSPHERIC CONDITIONS ACROSS MUCH OF THE E HALF OF THIS SYSTEM REMAIN STABLE...AS MENTIONED ABOVE...AND THIS SYSTEM NOW HAS LOW POTENTIAL FOR IMPROVED ORGANIZATION AND TROPICAL CYCLONE DEVELOPMENT. SATELLITE IMAGERY CONTINUES TO SHOW A LARGE CLUSTER OF MODERATE TO STRONG TSTMS ALONG THE MEXICAN COAST FROM LAS ISLAS TRES MARIAS TO OFFSHORE OF ACAPULCO AND EXTENDING W TO 109W. A BROAD LOW LEVEL TROUGH HAS DEVELOPED ACROSS THIS AREA...WHERE A POOL OF ABUNDANT TROPICAL MOISTURE RESIDES. OCEAN TEMPERATURES ACROSS THE AREA ARE SOME OF THE WARMEST ACROSS THE REGION...ALL SUGGESTING UNSTABLE CONDITIONS...AND VERY ACTIVE WEATHER WILL LIKELY PERSIST THERE FOR THE NEXT 6-12 HOURS AS IT SHIFTS SLOWLY WWD...AND ACROSS EXTREME S PORTIONS OF THE GULF OF CALIFORNIA. E OF 110W...MODERATE MONSOONAL FLOW PREVAILS...WITH AFTERNOON SCATTEROMETER PASSES INDICATING S TO SW WINDS 15 TO 20 KT ACROSS MUCH OF THE AREA N OF 02N TO THE MONSOON TROUGH...FROM THE COAST OF COLOMBIA TO 105W. RECENT ALTIMETER PASSES HAVE SHOWN WAVE HEIGHTS 5-6 FT WITHIN THIS AREA OF MODERATE WINDS...WITH PEAK SEAS TO 7 FT ALONG ABOUT 85W. $$ STRIPLING