000 AXPZ20 KNHC 121603 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC WED NOV 12 2014 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING...NORTHERLY NOCTURNAL DRAINAGE IS EXPECTED TO INCREASE TO 15-20 KT LATE TONIGHT THEN GRADUALLY INCREASE TO MINIMAL GALE WINDS BY THU EVENING. GALE CONDITIONS ARE EXPECTED TO PERSIST THROUGH FRI NIGHT...WITH 9-12 FT SEAS FORECAST TO BE CONFINED FROM 13N-15N BETWEEN 95W-96W. A RATHER EXTENSIVE AREA OF SEAS TO 9 FT IN NE SWELLS WILL PUSH SW DOWNSTREAM FROM THE GULF WITHIN 90 NM OF A LINE FROM 14N96W TO 12N97W TO 09N100W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXETNDS FROM 10N85W TO LOW PRES NEAR 09N88W 1010 MB TO 09N99W. IT RESUMES FROM 11N110W TO 10N122W TO 08N131W. ITCZ FROM 08N131W TO 08N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION EXITS FROM 03N-06N E OF 82W...AND WITHIN 60 NM OF ITCZ BETWEEN 132W-135W. SIMILAR ACTIVITY IS FROM 05N-09N BETWEEN 107W-110W. ...DISCUSSION... WEAKENING 1006 MB LOW PRES IS CENTERED NEAR 20N107W WITH 20-25 KT E-SE WINDS WITHIN 60 NM OF THE CENTER OVER THE E SEMICIRCLE WITH SEAS TO 8 FT. LATEST SATELLITE IMAGERY SHOWS ONLY ISOLATED WEAK SHOWERS AND TSTMS WITHIN 60 NM OF THE LOW. THE ACTIVITY IN THE SE QUADRANT IS BRUSHING THE COAST OF MEXICO ALONG AND JUST S OF CABO CORRIENTES. THE LOW IS FORECAST TO CONTINUE TO WEAKEN TO AN OPEN TROUGH TONIGHT. IN THE UPPER LEVELS...BROAD SCALE RIDING COVERS THE FAR EASTERN PART OF THE AREA E OF 105W...A TROUGH EXTENDS FROM THE SW U.S. SSW TO 20N112W TO NEAR 10N113W. BEHIND IT RIDGING IS PRESENT N OF 11N WITH THE ASSOCIATED MEAN AXIS EXTENDING FROM AN ELONGATED E TO W ANTICYCLONE AT 09N127W NNE TO N OF THE DISCUSSION AREA AT 32N126W. BROAD TROUGH IS NOTED TO THE W OF 136W. WATER VAPOR IMAGERY PORTRAYS A GENERAL DRY AND STABLE ATMOSPHERE AS A RESULT OF ABUNDANT MODERATE SUBSIDENCE PERSISTING THROUGHOUT. THE EXCEPTIONS ARE NEAR THE BASE OF THE AFOREMENTIONED TROUGH WHERE DIFFLUENT FLOW THERE IN COMBINATION WITH MOIST S-SW SURFACE WINDS CONVERGING INTO THE MONSOON TROUGH IS HELPING TO SUSTAIN SCATTERED MODERATE/ISOLATED STRONG CONVECTION AS DESCRIBED ABOVE UNDER ITCZ/MONSOON TROUGH. THE OTHER AREA OF DEEP LAYER MOISTURE IS ASSOCIATED WITH SIMILAR ACTIVE CONVECTION ON THE WESTERN PERIPHERY OF THE ANTICYCLONE WITHIN 60 NM OF THE ITCZ AS ALSO MENTIONED ABOVE. MOISTURE IN THE UPPER LEVELS IS STREAMING EASTWARD TO OVER THE WESTERN SECTION OF THE AREA AHEAD OF THE BROAD TROUGH NOTED AS SCATTERED TO BROKEN CIRRUS CLOUDS. AT THE SURFACE...A DISSIPATING STATIONARY FRONT EXTENDS FROM 32N133W TO 24N140W. A COLD FRONT HAS ENTERED THE FAR NW PORTION OF THE AREA ALONG A POSITION FROM 32N126W TO 27N140W. THE COLD FRONT WILL OVERTAKE THE REMNANTS OF THE STATIONARY FRONT THIS AFTERNOON. THE MERGED FRONT IS FORECAST TO EXTEND FROM NEAR 32N132W TO 24N140W BY EARLY ON THU AT WHICH TIME SEAS OF 8-12 FT IN NW SWELL ARE FORECAST TO THE NW OF A LINE FROM 32N124W TO 23N127W TO 10N140W WITH HIGHER SEAS OF 10-14 FT TO THE NW OF THE FRONT. THE SWELLS WILL SLOWLY SUBSIDE TO 8-10 FT BY EARLY FRI TO JUST W OF THE NORTHERN BAJA CALIFORNIA PENINSULA...AND W OF A LINE THAT EXTENDS FROM THERE SW TO 19N120W TO 05N140W. A WEAK 1009 MB IS CENTERED NEAR 19N116W. THE LOW IS UNDER VERY SUBSIDENT CONDITIONS ALOFT AS MENTIONED UNDER UPPER LEVELS. THESE CONDITIONS ARE CAPPING SHOWER AND TSTM ACTIVITY WITH THE LOW AS WELL AS OVER ITS SURROUNDING ENVIRONMENT. THE LOW IS FORECAST TO FURTHER WEAKEN TO A TROUGH BY EARLY THU...AND DISSIPATE THEREAFTER. GULF OF PAPAGAYO....THE PRES GRADIENT WILL TIGHTEN ENOUGH TO SUPPORT NE 20 KT WINDS BEGINNING EARLY ON FRI. THESE WINDS ARE EXPECT TO FURTHER INCREASE TO 25 KT ON SAT AS THE SPREAD SW TO NEAR 09N90W. $$ AGUIRRE