000 AXPZ20 KNHC 011004 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN JAN 01 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 06N77W TO LOW PRES NEAR 05N79W 1009 MB TO 05N95W...WHERE LOW LEVEL WINDS SUGGEST THAT IT TRANSITIONS TO THE ITCZ...AND CONTINUES TO 07N110W TO 08N122W TO 06N133W AND TO BEYOND 06N140W. SCATTERED TO NUMEROUS MODERATE/ISOLATED STRONG CONVECTION IS NOTED WITHIN 120 NM S OF THE AXIS BETWEEN 112W-119W...AND ALSO WITHIN 120 NM N OF THE AXIS BETWEEN 119W-122W. ...DISCUSSION... A LARGE AND QUITE POTENT LONG WAVE TROUGH IS W OF THE DISCUSSION AREA ALONG 145W...AND QUICKLY APPROACHING THE FAR NW PORTION WHILE DIGGING SEWD. AS A RESULT...VERY HIGHLY AMPLIFIED UPPER LEVEL RIDGING IS NOTED AHEAD OF THE TROUGH COVERING THE VAST MAJORITY OF THE EASTERN PACIFIC REGION N OF THE AREA WITH A MEAN RIDGE AXIS EXTENDING ROUGHLY ALONG 120W N OF 28N. A WEAK SHORTWAVE TROUGH...REMNANTS OF AN OLD CUT OFF DEEP LAYERED CYCLONE THAT MOVE INTO THE SW PORTION OF THE AREA A FEW DAYS AGO...IS SEEN EXTENDING FROM 23N132W SW TO 19N133W. THE LONG WAVE TROUGH IS FORECAST TO MOVE E TO NEAR 140W DURING THE NEXT 24 HOURS...AND NUDGE THE ENTIRE UPPER PATTERN ACROSS THE AREA EWD IN TURN. STRONG HIGH PRESSURE THAT HAD BEEN CENTERED N OF THE AREA THE PAST COUPLE OF DAYS HAS WEAKENED SIGNIFICANTLY...WITH THE PRIMARY HIGH PRESSURE NOW 1023 MB ANALYZED TO BE NEAR 34N127W WITH A RIDGE SW TO 28N130W. WITH THE HIGH WEAKENING...THE ZONE OF FRESH TRADEWINDS OVER THE WESTERN SECTION OF THE AREA HAS DIMINISHED IN AREAL COVERAGE DURING THE PAST COUPLE OF DAYS. IT IS NOW LIMITED FROM 06N-11N BETWEEN 125W-134W WITH NE-E WINDS OF 20 KT AND SEAS OF 8 FT. SATELLITE IMAGERY CONTINUES TO SHOW EXTENSIVE OVERCAST TO BROKEN MULTILAYERED CLOUDINESS RIDING UP OVER THE UPPER RIDGE AHEAD OF THE LONGWAVE TROUGH. THE CLOUDS COVER THE CENTRAL SECTION OF THE AREA FROM 05N TO 24N BETWEEN 110W-131W WITH ASSOCIATED ACTIVE SCATTERED TO NUMEROUS MODERATE/ISOLATED STRONG CONVECTION AS MENTIONED ABOVE UNDER ITCZ/MONSOON TROUGH. THIS ACTIVITY IS SUPPORTED BY LOW TO MID LEVEL CONVERGENCE AS A RESULT OF A STRONG EQUATORIAL UPPER JET OCCURRING BETWEEN THE SHORTWAVE TROUGH AND AN UPPER CYCLONE S OF THE EQUATOR. SCATTERED SHOWERS ARE ALSO POSSIBLE FROM 10N TO 16N BETWEEN 118W-126W. THE AS THE UPPER PATTERN AND ASSOCIATED EQUATORIAL JET SHIFT E IN TANDEM WITH THE LONGWAVE TROUGH AND RIDGE TO ITS E DURING THE NEXT 24 HOURS...LOOK FOR THE MAIN PORTION OF THE ACTIVE CONVECTION TO SHIFT E OF 120W. THE HIGH PRESSURE RIDGE WILL SHIFT EASTWARD ALLOWING FOR A A SURFACE COLD FRONT...PRESENTLY WITHIN ABOUT 180 NM NW OF 32N140W...TO MOVE ACROSS THE FAR NW WATERS THIS MORNING. AN ASCAT PASS FROM SHORTLY PAST 0600 UTC THIS MORNING SHOWED S-SW WINDS OF MOSTLY 20 KT OVER THE FAR NW PORTION IN ADVANCE OF THE FRONT. THE COLD FRONT WILL BEGIN TO QUICKLY WEAKEN ONCE IT MOVES INTO THE AREA THIS MORNING...AND REACH FROM NEAR 30N133W TO 23N140W BY LATE TONIGHT...THEN DISSIPATE MON NIGHT AT IT EXITS THE DISCUSSION AREA OVER INLAND THE SW U.S. HOWEVER...AN EXPANSIVE WIND FIELD BEHIND THE FRONT HAS GENERATED LARGE LONG PERIOD NW SWELL THAT WILL PROPAGATE INTO THE AREA...WITH COMBINED SEAS POSSIBLY AS HIGHER AS 19 OR 20 FT EXPECTED TO PEAK MON MORNING ACROSS THE FAR NW CORNER OF THE AREA. GULF OF PAPAGAYO... FRESH TO STRONG TRADEWINDS OVER THE WESTERN CARIBBEAN CONTINUE TO FUNNEL THROUGH THE NICARAGUA MOUNTAINS INTO THE GULF OF PAPAGAYO. WINDS WILL PEAK AT 20-25 KT PRIMARILY DURING THE LATE NIGHT AND EARLY MORNING HOURS WITH THE ADDED COMPONENT OF NOCTURNALLY DRIVEN KATABATIC WINDS. DOWNSTREAM SEAS WILL GENERALLY RUN 6-8 FT BRIEFLY BUILDING TO 9 FT AFTER PEAK WIND FLOW. GULF OF TEHUANTEPEC... A WEAK TROUGH OVER THE YUCATAN PENINSULA JUST E OF THE BAY OF CAMPECHE COMBINED WITH HIGH PRESSURE OVER EASTERN MEXICO IS CREATING LOCALIZED NORTHERLY WINDS WHICH ARE FUNNELING THROUGH THE CHIVELA PASS RESULTING IN FRESH WINDS OVER THE GULF OF TEHUANTEPEC. MODEL GUIDANCE HAS BEEN VERY CONSISTENT IN DEPICTING WINDS FUNNELING THROUGH THE CHIVELA PASS WHILE INCREASING DURING TODAY AND TONIGHT AHEAD OF A STRONG COLD FRONT THAT WILL RAPIDLY MOVE SE ACROSS THE GULF OF MEXICO. WINDS ARE EXPECTED TO REACH MINIMAL GALE FORCE BY EARLY THIS EVENING...THEN CONTINUE TO INCREASE REACHING TO 40 KT BY LATE TONIGHT...AND TO STORM STRENGTH OF 40-50 KT BY LATE MON NIGHT. WAVEWATCH GUIDANCE BUILDS MAXIMUM SEAS TO NEAR 18 FT BY LATE MON NIGHT OVER THE FAR SRN PART OF THE GULF. GULF OF PANAMA... FRESH TO STRONG NE WINDS OVER THE SW CARIBBEAN WILL FUNNEL INTO ACROSS PANAMA...AND MAINTAIN FRESH 20 KT NLY WINDS OVER THE GULF OF PANAMA DURING TODAY. THESE WINDS THEN DIMINISH TO LESS THAN 20 KT EARLY THIS EVENING...THEN MATERIALIZE AGAIN BY LATE MON NIGHT. THE COMBINATION OF SW MONSOONAL FLOW TO THE S OF THE GULF AND THE NLY WINDS HAS LEAD TO A WEAK LOW OF ABOUT 1010 MB TO BECOME NOTICEABLE W OF COLOMBIA AT 05N79W. THE LOW IS EXPECTED TO LINGER IN THAT GENERAL AREA THROUGH THE NEXT 48 HRS. ISOLATED SHOWERS AND WEAK ISOLATED TSTMS ARE POSSIBLE FROM TIME TO TIME NEAR THE LOW. GULF OF CALIFORNIA... THE WEAKENED HIGH PRES CENTER N OF THE AREA IS SHIFTING EWD AND APPROACHING THE COAST OF CENTRAL CALIFORNIA. AS THIS OCCURS...SUFFICIENT PRES GRADIENT WILL ENSUE BETWEEN THE HIGH AND LOW PRES ALONG THE SIERRA MADRES OCCIDENTALES...LEADING TO FRESH NLY WINDS DOWN THE GULF OF CALIFORNIA BEGINNING EARLY TONIGHT N OF 28N WITH WINDS OF 20 KT. THESE WINDS SPREAD S TO NEAR 26N LATE TONIGHT...AND THEN DIMINISH TO LESS THAN 20 KT MON. $$ AGUIRRE