000 AXPZ20 KNHC 061603 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE NOV 06 2012 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM 08N78W TO 08N90W TO 07N103W TO 07N114.5W WHERE IT ENDS. THE ITCZ AXIS BEGINS AT 11N124W TO 07N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION EXISTS FROM 04N TO 07N BETWEEN 78W-81W. ...DISCUSSION... AN UPPER LOW LOCATED NEAR 25N126W SUPPORTS A SURFACE TROUGH THAT EXTENDS FROM 32N124W SW TO 26N126W. A TROUGH EXTENDS FROM THE UPPER LOW SSW TO 17N128W...AND SEWD TO 12N123W TO NEAR 05N118W. ONLY OVERCAST TO BROKEN LOW/MID CLOUDS WITH ISOLATED SHOWERS ARE SEEN WITHIN 210 NM W OF THE SURFACE TROUGH. A JET STREAM BRANCH ACROSS THE TROUGH THAT EXTENDS FROM THE LOW IS OBSERVED TO STRETCH FROM 11N125W NE TO 21N115W AND E TO OVER NW MEXICO. BROKEN MID AND HIGH CLOUDS ARE SEEN STREAMING NEWD WITHIN 140 NM EITHER SIDE OF THE JET STREAM BRANCH. THESE CLOUDS REACH TO NEAR 115W BEFORE THEY EVAPORATE IN DRIER AIR. E OF THE TROUGH...A 1019 MB SURFACE HIGH IS ANALYZED AT 28N120W. GLOBAL MODELS FORECAST THE SURFACE TROUGH TO SLOWLY MOVE EASTWARD THROUGH WED AS A WEAKENING COLD FRONT ADVANCES SEWD OVER THE NE PORTION OF THE BASIN. THE FRONT WILL MERGE WITH TROUGH BY WED NIGHT AS THE 1019 MB HIGHER DISSIPATES. TO THE W OF THE UPPER LOW...A HIGHLY AMPLIFIED MID/UPPER RIDGE EXTENDS FROM N OF THE AREA AT 32N129W SW TO 25N137W TO JUST W OF AREA AT 14N142W. SATELLITE WATER VAPOR IMAGERY SHOWS ABUNDANT STRONG SUBSIDENCE AND ASSOCIATED DRY AIR COVERING MUCH OF THE WESTERN AND CENTRAL PORTIONS OF THE AREA. SCATTERED TO BROKEN LOW CLOUDS WITH ISOLATED SHOWERS MOVING W ARE NOTED W OF ABOUT 117W. TO THE W OF THE MID/UPPER LEVEL RIDGE...A MID/UPPER LEVEL CYCLONIC CIRCULATION IS FORMING NEAR 31N148W. THIS IS ON THE SRN END OF A BROAD TROUGH JUST TO NW AND N OF THE AREA. UPPER LEVEL GLOBAL MODEL GUIDANCE SUGGESTS THAT THIS LOW WILL BECOME CUT-OFF TONIGHT INTO WED AS JET ENERGY OVER THE NE PACIFIC DIGS INTO THE MAIN TROUGH OVER THE WEST COAST...ALLOWING THE UPPER LOW NEAR 25N126W TO OPEN UP AND LIFT NE. THE DEEPENING TROUGH OVER THE WEST COAST WILL BE THE CULPRIT IN SENDING THE WEAKENING COLD FRONT...MENTIONED ABOVE...SEWD INTO THE NE PORTION OF THE AREA ON WED. OVER THE EASTERN PORTION OF THE AREA...BROAD SCALE MID/UPPER LEVEL RIDGING IS EVIDENT SE OF A LINE FROM NW MEXICO TO 15N117W TO 05N119W. AN ASSOCIATED ANTICYCLONE IS IDENTIFIED TO BE AT 13N98W. PATCHES OF DEEP LEVEL ATMOSPHERIC MOISTURE IS OBSERVED ACROSS THIS PORTION OF THE AREA...WITH SCATTERED MODERATE/ISOLATED STRONG CONVECTION MOSTLY IN CLUSTERS. ONE SUCH POCKET OF CONVECTION IS WITHIN 30 NM OF A LINE FROM 20N108W TO 20N111W. ELSEWHERE AT THE SURFACE...A PAIR 1008 MB LOW PRES SYSTEMS PERSIST...ONE NEAR 16N11W AND THE OTHER ONE NEAR 13N123W...THE REMNANT OF ROSA. BOTH OF THESE WILL OPEN INTO TROUGHS TODAY THEN DISSIPATE THROUGH WED. MEANWHILE...FRESH TO STRONG GAP WIND FLOW CONTINUES TO PULSE THROUGH THE GULF OF TEHUANTEPEC. A HIGH RESOLUTION ASCAT PASS FROM 04 UTC LAST NIGHT INDICATED 20 TO 30 KT WINDS THROUGH THE GAP. A COLD FRONT WILL PUSH INTO THE SW GULF OF MEXICO THIS AFTERNOON. THE NORTHERLY FLOW ALONG WITH DENSER AIR AND HIGHER PRES BEHIND THE FRONT WILL ALLOW WINDS TO INCREASE TO GALE FORCE THROUGH TEHUANTEPEC BY THIS EVENING. THE EVENT WILL PERSIST AT LEAST THROUGH 48 HOURS...ALLOWING SEAS TO BUILD TO 14 FT IN THE GULF OF TEHUANTEPEC WITH A SWATH OF 8 TO 11 FT POSSIBLY AS FAR AS 600 NM DOWNSTREAM FROM THE GULF. FURTHER SOUTH...GULF OF PAPAGAYO GAP WINDS ARE EXPECTED TO INCREASE TO 20-25 KT WED AND CONTINUE INTO THU NIGHT...WITH PEAK WINDS MAINLY IN EARLY MORNING HOURS. RESIDUAL NW SWELL OVER MUCH OF THE AREA N OF 15N W OF 120W WILL DECAY BELOW 8 FT THROUGH TODAY. ENSEMBLE WAVE GUIDANCE INDICATES THAT SW SWELL TO 8 FT WILL PUSH N OF THE EQUATOR TO AS FAR N AS 05N BETWEEN 95W AND 105W BY LATE WED. LOOKING AHEAD TO THU...THIS SW SWELL WILL MIX WITH SHORTER PERIOD NE SWELL EMERGING OUT OF THE TEHUANTEPEC GAP WIND EVENT TO PRESENT A LARGE AREA OF CONFUSED SEAS FROM 08N TO 14N BETWEEN 95W AND 115W. $$ AGUIRRE